Powered by Google-Search & Google-Books Chinese Standards Shop Database: 169759 (Nov 29, 2020)
HOME   Quotation   Tax   Examples Standard-List   Contact-Us   View-Cart
  

GB/T 1029-2005

Chinese Standard: 'GB/T 1029-2005'
Standard IDContents [version]USDSTEP2[PDF] delivered inStandard Title (Description)StatusRelated Standard
GB/T 1029-2005English520 Add to Cart 0--10 minutes. Auto immediate delivery. Test procedures for three-phase synchronous machines Valid GB/T 1029-2005

  In 0~10 minutes time, full copy of this English-PDF will be auto-immediately delivered to your email. See samples for translation quality.  

BASIC DATA
Standard ID GB/T 1029-2005 (GB/T1029-2005)
Description (Translated English) Test procedures for three-phase synchronous machines
Sector / Industry National Standard (Recommended)
Classification of Chinese Standard K21
Classification of International Standard 29.160.01
Word Count Estimation 56,521
Date of Issue 2005-08-26
Date of Implementation 2006-04-01
Older Standard (superseded by this standard) GB/T 1029-1993
Quoted Standard GB 755-2000; GB/T 5321; GB/T 7409.3; GB 10068; GB/T 10069.1; GB/T 10069.2; GB/T 15706.1-1995; GB/T 15706.2-1995; GB/T 16856-1997
Adopted Standard IEC 60034-4-1985, MOD
Drafting Organization Harbin Institute of Electronics
Administrative Organization National Standard Authority rotating electrical generators at the Technical Committee
Regulation (derived from) Announcement of Newly Approved National Standards No. 11 of 2005 (No. 85 overall)
Proposing organization China Machinery Industry Federation
Issuing agency(ies) General Administration of Quality Supervision, Inspection and Quarantine of the People Republic of China, China National Standardization Administration Committee
Summary This standard specifies the three-phase synchronous motor test methods. This standard applies to the rated power of 1kW (kVA) and above synchronous motors, generators and synchronous condenser. Not suitable for dc excitation winding synchronous motors, variable frequency power supply static synchronous motor test can refer to the use.

GB/T 1029-2005
NATIONAL STANDARD OF THE
PEOPLE’S REPUBLIC OF CHINA
ICS 29.160.01
K 21
Replacing GB/T 1029-1993
Test Procedures for Three-Phase Synchronous
Machines
三相同步电机试验方法
ISSUED ON: AUGUST 26, 2005
IMPLEMENTED ON: APRIL 01, 2006
Issued by: General Administration of Quality Supervision, Inspection and
Quarantine;
Standardization Administration of PRC.
Table of Contents
Foreword ... 6
1 Scope ... 8
2 Normative References ... 8
3 Preparation for Test ... 9
4 General Test Items ... 10
4.1 Determination of insulation resistance ... 10
4.2 Determination of DC resistance of winding in actual cold state ... 11
4.3 Determination of shaft voltage ... 14
4.4 Determination of no-load characteristics ... 15
4.5 Determination of steady-state short-circuit characteristics ... 17
4.6 Exciter test ... 18
4.7 Overspeed test ... 18
4.8 Inter-turn short-circuit test of non-salient-pole generator rotor ... 18
4.9 Determination of vibration ... 18
4.10 Inspection of sealing state and determination of hydrogen leakage ... 19
4.11 Inter-turn impulse withstand voltage test ... 19
4.12 Short-time voltage rising test ... 19
4.13 Power frequency withstand voltage test ... 19
4.14 DC leakage current test and DC withstand voltage test for armature winding
insulation ... 22
4.15 Determination of sinusoidal distortion rate of voltage waveform ... 24
4.16 Determination of noise ... 25
4.17 Determination of telephone harmonic factor ... 25
5 Efficiency Measurement ... 26
5.1 Direct determination of efficiency ... 26
5.2 Indirect determination of efficiency ... 29
5.3 Calorimetric method ... 31
5.4 Determination of various losses corresponding to rated load ... 31
5.5 Self-deceleration test ... 36
5.6 Determination of efficiency at other loads ... 38
6 Temperature Rise Test ... 38
6.1 Temperature measurement method ... 38
6.2 Determination of cooling medium temperature during temperature rise test 39
6.3 Determination of the temperature of each part of the motor during the
temperature rise test ... 40
6.4 Correction of the measured temperature of each part of the motor after being
disconnected from the power supply ... 41
6.5 Short-circuit insulation braking method ... 41
6.6 Test method of temperature rise ... 42
7 Determination of Voltage Adjustment Performance at Self-Excited Constant
Voltage ... 47
7.1 Determination of steady-state voltage regulation ... 48
7.2 Determination of the degree of voltage deviation when the generator operates
under an asymmetric load ... 49
7.3 Determination of change rate of transient voltage ... 49
8 Determination of Torque and Moment of Inertia ... 50
8.1 Determination of locked-rotor current and locked-rotor torque ... 50
8.2 Determination of nominal pull-in torque ... 53
8.3 Determination of pull-out torque of synchronous motor ... 55
8.4 Short-time over-torque test of motor ... 57
8.5 Determination of moment of inertia ... 57
9 Overcurrent and Mechanical Strength Test ... 58
9.1 Accidental overcurrent test ... 58
9.2 Overload test ... 58
9.3 Short-circuit mechanical strength test ... 58
10 Negative Sequence Current Withstand Capability Test ... 59
11 Determination of Dynamic Characteristics of Stator Winding Ends ... 59
12 Determination of Parameters (this Clause Equivalently Adopt IEC 60034-4)
... 59
12.1 Description ... 59
12.2 Determine parameters by no-load saturated characteristics and three-phase
steady-state short-circuit characteristics ... 61
12.3 Zero-power factor overexcitation test ... 62
12.4 Determination of excitation current at rated voltage and rated armature
current during zero power factor overexcitation ... 62
12.5 Use the no-load characteristic, three-phase steady-state short-circuit
characteristic and excitation current corresponding to the rated voltage and rated
armature current at zero power factor (overexcitation) to determine the Potier
reactance ... 63
12.6 Use Potier diagram to determine the rated excitation current ... 64
12.7 Use the ASA diagram to determine the rated excitation current ... 66
12.8 Use the Swedish diagram to determine the rated excitation current ... 67
12.9 Reverse excitation test ... 68
12.10 Determine Xq by reverse excitation test ... 68
12.11 Low slip-ratio test ... 69
12.12 Determine Xq by low slip-ratio test ... 70
12.13 Determination of power angle δ by load test ... 70
12.14 Determine Xq as per the method measuring the power angle by the load test
... 71
12.15 Three-phase sudden short-circuit test ... 71
12.16 Parameters determined by three-phase sudden short-circuit test ... 75
12.17 Voltage recovery test ... 76
12.18 Determine parameters by voltage recovery test ... 77
12.19 Externally-applied voltage test when the rotor is located in the positions of
direct-axis and quadrature-axis against the magnetic field of the armature winding
... 78
12.20 Determine the parameters by the externally-applied voltage test when the
rotor is located in the positions of direct-axis and quadrature-axis against the
magnetic field of the armature winding ... 78
12.21 Externally-applied voltage test when the rotor is in any position ... 79
12.22 Determine the parameters by the externally-applied voltage test when the
rotor is at any position ... 79
12.23 Two-phase steady-state short-circuit test ... 80
12.24 Determine the parameters by two-phase steady-state short-circuit test .. 81
12.25 Reversed phase sequence test ... 82
12.26 Determine the parameters by reversed phase sequence test ... 82
12.27 Test of single-phase voltage externally-applied to three-phase winding .. 83
12.28 Determine the parameters by the test of single-phase voltage externally-
applied to three-phase winding ... 83
12.29 Steady-state short-circuit test of two-phase to neutral-point ... 84
12.30 Determine the parameters by steady-state short-circuit test of two-phase to
neutral-point ... 84
12.31 Excitation current decay test when the armature winding is open-circuited
... 85
12.32 Determine T’do by the excitation current decay test when the armature
winding is open-circuited ... 85
12.33 Excitation current decay test when the armature winding is short-circuited
... 85
12.34 Determining T’d by the excitation current decay test when the armature
winding is short-circuited ... 86
12.35 Torsion test of suspended rotor ... 86
12.36 Determine Tj and H by the torsion test of the suspended rotor ... 86
12.37 Swing test of auxiliary pendulum ... 87
12.38 Determine Tj and H with the swing test of auxiliary pendulum ... 88
12.39 No-load self-deceleration test ... 88
12.40 Determine Tj and H with no-load self-deceleration test ... 88
12.41 On-load self-deceleration test of mechanically connected units, while
synchronous motor run as electric motor ... 89
12.42 Determine Tj and H by the on-load self-deceleration test when the
synchronous motor runs as an electric motor ... 89
12.43 Load-dump acceleration test when the motor runs as a generator ... 90
12.44 Determine Tj and H by the load-dump acceleration test when the motor runs
as a generator ... 90
12.45 Rated voltage regulation ΔUN ... 90
12.46 Determine parameters by known test parameters through calculation ... 91
Appendix A (Normative) Obtain Value Δθ at the Excitation Winding Temperature
Rise by No-Load Short-Circuit Method ... 94
Appendix B (Informative) Symbols and Units of Physical Quantities ... 96
Test Procedures for Three-Phase Synchronous
Machines
1 Scope
This Standard specifies the test methods for three-phase synchronous motor.
This Standard is applicable to synchronous motors, generators and synchronous
cameras with a rated power of 1 kW (kVA) and above. It is not applicable to
synchronous motors without DC excitation winding. The test of synchronous motors
powered by static variable frequency power supply can be used for reference.
2 Normative References
The provisions in following documents become the provisions of this Standard through
reference in this Standard. For dated references, the subsequent amendments
(excluding corrigendum) or revisions do not apply to this Standard, however, parties
who reach an agreement based on this Standard are encouraged to study if the latest
versions of these documents are applicable. For undated references, the latest edition
of the referenced document applies.
GB 755-2000 Rotating Electrical Machines -Rating and Performance (idt IEC
60034-1:1996)
GB/T 5321 Measurement of Loss and Efficiency for Large AC Electrical Machines
by the Calorimetric Method (GB/T 5321-1985, neq IEC 60034-2A:1974)
GB/T 7409.3 Excitation System for Synchronous Electrical Machines - Technical
Requirements of Excitation System for Large and Medium Synchronous
Generators
GB 10068 Mechanical Vibration of Certain Machines with Shaft Heights 56mm
and Higher – Measurement, Evaluation and Limits of Vibration (GB 10068-2000,
idt IEC 60034-14:1996)
GB/T 10069.1 Measurement of Airborne Noise Emitted by Rotating Electrical
Machinery and the Noise Limits-Engineering Method for the Measurement of
Airborne Noise
GB/T 10069.2 Measurement of Airborne Noise Emitted by Rotating Electrical
Machinery and the Noise Limits-Survey Method for the Measurement of Airborne
Noise
GB/T 10585 Fundamental Requirements of Excitation Systems Medium and Small
Synchronous Machines
GB/T 15548 General Specification for Three-Phase Synchronous Generators
Driven by Reciprocating Internal Combustion Engine
JB/T 6227 Checking Methods and Evaluation of Sealing of Hydrogen-Cooled
Electrical Machines
JB/T 7836.1 Electric Heater for Electrical Machine Part 1: General Technique
Specifications
JB/T 8445 Test Method of Bearing Capacity of Three-phase Synchronous
Generator for Negative-sequence Current
JB/T 8446 Methods for the Determination of Interturn Short-Circuit in the Rotor
Winding of Cylindrical Synchronous Generators
JB/T 8990 Modal Test Analyses and Natural Frequency Measurement Methods of
Large Turbo-Generators on Stator End Windings and Evaluation Criteria
JB/T 9615.1 Test Methods of the Interturn Insulation on Random Wound Winding
for AC Low-Voltage Machines
JB/T 9615.2 Test Limits of the Interturn Insulation on Random Wound Winding for
AC Low-Voltage Machines
JB/T 10098 Impulse Voltage Withstand Levels of Rotating A.C. Machines with
Form-Wound Stator Coils (JB/T 10098-2000, idt IEC 60034-15:1995)
JB/T 10500.1 Embedded Thermometer Resistance for Electrical Machines - Part1:
General Specification, Measuring Methods and Examine Rule
IEC 60034-2 Rotating Electrical Machines – Part 2: Test Methods for Losses and
Efficiency
IEC 60034-4 Rotating Electrical Machines – Part 4: Test Methods for Parameters
3 Preparation for Test
During the test, the accuracy of the used electrical measuring instruments and meters
shall be no less than Level-0.5 (except for megohmmeters). When measuring the
three-phase power, the three-phase watt-meters with an accuracy of Level-1.0 shall
be allowed to use. When measuring temperature, a thermometer with an error of ± 1°C
temperature detector) to measure the temperature of the motor winding, iron core and
ambient temperature. The difference between the measured temperature and the
temperature of the cooling medium shall not exceed 2K. For large and medium-sized
motors, the thermometer shall be taken the measures for heat insulation from the
outside; and the time for placing the thermometer shall be no less than 15min.
When measuring the temperature of the armature winding and auxiliary winding (such
as self-excited constant voltage generator harmonic winding, etc.), the temperature of
the winding end and winding slot shall be measured at different locations according to
the size of the motor (if there is difficulty, the temperature of iron core teeth and the
surface of the iron core yoke may be measured); and take the average value as the
temperature of the winding in actual state.
When measuring the temperature of the exciting winding of a salient pole type motor,
the temperature may be directly measured at several places on the winding surface;
and take the average value as the temperature of the winding in actual cold state.
When measuring the temperature of the exciting winding of a non-salient pole motor,
the temperature of the winding surface shall be measured. In case of difficulties, the
surface temperature of the rotor may be used instead. For large and medium-sized
motors, the measurement point shall be no less than three points; and take the average
value as the temperature of winding in the actual cold state.
When measuring the temperature of the excitation device winding (such as transformer,
reactor winding, etc.) of a self-excited constant voltage generator, use a thermometer
to measure the surface temperature of the iron core or winding as the temperature of
the winding in actual cold state.
For liquid directly cooled windings, when the liquid is passed, in case that the difference
between the temperature of the liquid at the inlet and outlet of the winding does not
exceed 1K, and the temperature difference between the iron core temperature and the
ambient temperature does not exceed 2K; take the average value of the liquid
temperature at the inlet and outlet of the winding as the temperature of winding in the
actual cold state.
4.2.2 Determination of DC resistance of the winding
The DC resistance of the winding may be measured by the bridge method, micro-
ohmmeter method, voltmeter ammeter method or other measurement methods.
4.2.2.1 When measuring the DC resistance of the winding by automatic detection
devices, digital micro-ohmmeters and other instruments, the test current through the
tested winding shall not exceed 10% of its rated current; and the energization time
shall not exceed 1min.
4.2.2.2 When measuring by a bridge, each resistance shall be measured three times.
Unless otherwise specified, the test shall start at 1.3 times the rated voltage of the
armature; and adjust the terminal voltage and excitation current until the minimum
voltage at which the motor is not out of step. Read 7~ 9 points throughout the process.
Each point shall be read the applied voltage, excitation current and frequency (or
speed).
If the three-wire voltage is symmetrical, except for reading the three-wire voltage at the
rated voltage, other points may only read the one-wire voltage.
If the frequency during the test is different from the rated frequency, the no-load
armature voltage is corrected according to Formula (7).
4.4.3 For synchronous motors under 1 000 kVA, the excitation current at rated voltage
may be taken as much as possible in the inspection test.
4.5 Determination of steady-state short-circuit characteristics
4.5.1 When measuring the three-phase steady-state short-circuit characteristics, use
a low-impedance conductor to reliably short-circuit the line end as close as possible to
the armature winding end. During the test, the motor shall be operated in a separate
excitation mode.
4.5.2 Generator method
During the test, drag the tested motor to the rated speed; adjust the excitation current
so that the armature current is about 1.2 times the rated current; and read the armature
current and the excitation current at the same time. Gradually reduce the excitation
current, so that it is reduced to zero. Totally, read 5 ~ 7 points, and then draw the short-
circuit characteristic curve IK = f(If). If the three-phase current is symmetrical, in addition
to reading the three-wire current at the rated current, other points may only read the
one-wire current.
4.5.3 Motor method (self-deceleration method)
The tested motor runs at no-load. After cutting off the power supply, immediately
reduce the excitation current to zero and cut off the excitation power supply; and then
the three-phase armature windings are short-circuited at the same time by the switch
prepared in advance.
Turn on the excitation power, adjust the excitation current so that the armature current
is about 1.2 times the rated value; at the same time, read the armature current and the
excitation current. Gradually reduce the excitation current, and read 5 ~ 7 points within
the range allowed by the accuracy of the apparatus. If the test data read during a self-
deceleration is insufficient, the above operation can be repeated until sufficient test
data is obtained. Then draw the short-circuit characteristic curve IK = f(If).
4.10 Inspection of sealing state and determination of hydrogen leakage
The test method shall be carried out according to the method specified in JB/T 6227.
4.11 Inter-turn impulse withstand voltage test
The inter-turn impulse withstand voltage test shall be carried out in accordance with
the methods specified in JB/T 10098, JB/T 9615.1 and JB/T 9615.2.
4.12 Short-time voltage rising test
The test shall be carried out when the motor is at no-load. Except for the following
provisions, the externally applied voltage (motor) or induced voltage (generator) of the
test is 130% of the rated voltage.
For motors with a no-load voltage at rated excitation current of 130% more than the
rated voltage, the test voltage shall be equal to the no-load voltage at rated excitation
current.
If there are no other provisions of relevant standards or technical documents, the test
time is 3min, except for the following provisions.
If at 130% rated voltage, the test time of the motor with no-load current exceeding the
rated current may be shortened to 1min. For a shock exciter, if the voltage during high-
speed excitation exceeds 130% of the rated voltage, the test shall be carried out at the
limit voltage during high-speed excitation for a period of 1min.
When increasing the test voltage to 130% of the rated voltage, it is allowed to increase
the frequency or speed at the same time, but not exceeding 115% of the rated speed
or the speed specified in the overspeed test. The allowable increased speed value
shall be specified in the standards for various types of motors.
For generators with relatively saturated magnetic circuit, when the speed increases to
115% and the excitation current has also increased to the allowable limit, if the induced
voltage value does not reach the specified test voltage, the test is allowed to be carried
out at the maximum reachable voltage.
4.13 Power frequency withstand voltage test
The frequency of the test voltage is the power frequency; and the voltage waveform
shall be as close to the sinusoidal waveform as possible. During the whole withstand
voltage test, necessary safety protection measures shall be taken, and special persons
shall be monitored around the tested motor.
4.13.1 Test requirements
4.13.1.1 Unless otherwise specified, the power frequency withstand voltage test shall
5 Efficiency Measurement
5.1 Direct determination of efficiency
Measure the output power and input power of the tested motor to determine the
efficiency.
5.1.1 During the test, the tested motor shall be operated at rated power, rated voltage,
rated speed and rated power factor until it is thermally stable and then measured.
When measuring the input power and output power of the tested motor, the armature
current, excitation current and cooling medium temperature of the tested motor shall
be measured simultaneously.
When the temperature of the cooling medium is not 25°C, the temperature rise and the
DC resistance of each winding shall also be measured at the same time (it may be
measured immediately after the test, but it shall be corrected to the moment of power
cut).
5.1.2 When measuring the motor efficiency by the direct method, any of the following
methods shall be used.
5.1.2.1 Braking method
When the tested motor operates as a motor, it shall be connected to a brake or a
dynamometer; and use the brake or dynamometer to measure the torque of the tested
motor. At the same time, measure its speed to determine the output power of the motor.
The input power shall be measured by the electrical instrument.
When the tested motor operates as a generator, it shall use a dynamometer to drag
the tested motor; and use the dynamometer to measure the input power of the tested
motor; and use an electrical instrument to measure the output power of the tested
motor.
Since the speed of the motor directly affects the calculation of power, special attention
must be paid to the measurement of the speed.
The test shall be conducted as close as possible to the temperature reached at the
end of the time specified in the rating, and the winding resistance does not need to be
converted into temperature.
5.1.2.2 Calibration motor method
The tested motor is mechanically coupled to the calibrated motor. Use the calibrated
motor to measure the input (for generator) or output (for motor) power of the tested
motor; and use the electrical instrument to measure the output (for generator) or input
(for motors) power of the tested motor.
The test shall be conducted as close as possible to the temperature reached at the
end of the time specified in the rating, and the winding resistance does not need to be
converted into temperature.
5.1.2.3 Towing method
Two identical motors are mechanically coupled; one is operated as a motor and the
other is operated as a generator. Use electrical instrument to measure the input power
of the motor and the output power of the generator. When the operating conditions of
the two machines are basically the same, it may be assumed that the loss is evenly
shared. Then the output power of the motor is the difference between input power and
the half of the total loss; while the input power of the generator is the sum between the
input power and the half of the total loss.
The test shall be conducted as close as possible to the temperature reached at the
end of the time specified in the rating, and the winding resistance does not need to be
converted into temperature.
5.1.3 Determination of total loss
5.1.3.1 Feedback method
Two identical motors are mechanically and electrically coupled together, one operates
as a motor and the other operates as a generator. The loss of these two machines is
provided by the grid to which they are connected, or supplied by a mechanically
coupled dynamometer or calibrated motor.
When the operating conditions of the two machines are basically the same, it may be
assumed that the losses are equally shared, then the input and output power of the
tested motor may be determined as per the method in 5.1.2.3.
The test shall be conducted as close as possible to the temperature reached at the
end of the time specified in the rating, and the winding resistance does not need to be
converted into temperature.
Because the size of the power transfer between the two machines varies with the size
of the power angle, there shall be a correct power angle relationship when the two
machines are mechanically coupled.
5.1.3.2 Zero power factor test
The tested motor operates as an idling motor at rated voltage and rated speed; the
power factor is around zero; and adjust the excitation current so that the primary
winding current reaches the rated value. The total loss is equal to the power input in
Δθa – temperature rise value of the armature winding when measuring efficiency, in K;
Δθf – temperature rise value of excitation winding when measuring efficiency, in K;
θa – temperature of armature winding when measuring efficiency, in °C;
θf – temperature of excitation winding when measuring efficiency, in °C;
k – copper winding takes 235; while the non-copper winding shall be taken value as
per the provisions of 7.6.2.2 in GB 755-2000.
5.2 Indirect determination of efficiency
5.2.1 When the efficiency of the motor is obtained by the loss analysis method, the
following losses shall be measured or calculated, respectively.
5.2.1.1 Constant loss, recorded as P0, including:
a) Iron loss (including no-load stray loss), recorded as PFe;
b) Bearing friction loss;
c) wind consumption;
d) Brush friction loss.
The sum of the losses in the above b), c) and d) is called mechanical loss; and is
recorded as Pfw.
5.2.1.2 Load loss
The I2R loss in the motor armature winding; recorded as Pcua.
5.2.1.3 Excitation loss; recorded as Pf, including:
a) I2R loss of excitation winding; recorded as Pcuf;
b) The loss of the varistor; recorded as PR;
C) Brush electrical losses; recorded as Prs;
d) Exciter loss; recorded as PE;
e) The loss of the device with excitation; recorded as PZE;
f) I2R loss of the device with auxiliary winding.
5.2.1.4 Stray loss; recorded as Pd, including:
5.3 Calorimetric method
If the loss cannot be determined by the method specified in 5.1 or 5.2, it can be
measured by calorimetric method. For the test method, see GB/T 5321.
5.4 Determination of various losses corresponding to rated load
5.4.1 Determination of constant loss
5.4.1.1 No-load generator method: the excitation current of the tested motor is supplied
by an independent DC power source; and it operates as a no-load generator. The
tractor shall be an analyzed motor or other prime mover (e.g. dynamometer) that can
accurately measure or calculate its output power. During the test, the speed shall be
the rated speed of the tested motor. After the bearing friction loss and the brush friction
loss are stable, measure the output power of the prime mover at different voltages of
the generator. This output power is the constant loss (P' 0) of the tested motor at the
corresponding voltage.
In order to separate iron loss from mechanical loss, draw a curve by the constant loss
measured at various voltages against the square of the per unit voltage, as shown in
Figure 8. The loss corresponding to is the mechanical loss of the tested motor;
and the loss corresponding to the rated voltage is the constant loss of the tested motor
at the rated voltage. The difference between the two is the iron loss (PFe) of the tested
motor at the rated voltage; it also serves as the iron loss of the tested motor at rated
load.
5.4.1.2 No-load motor method: the tested motor is connected to an actual symmetrical
stable power supply with adjustable rated frequency and voltage to operate as a no-
load motor. The excitation current is supplied by an independent DC power supply.
Adjust the excitation current of the tested motor to minimize the armature current. After
the bearing friction loss and brush friction loss are stable, measure the input power Pin
and armature current I0 at different voltages; and measure the DC resistance Ra (can
be measured immediately after the test, but it shall be corrected to the moment of
power cut) of the armature winding. The constant loss P' 0 (kW) of the tested motor at
the corresponding voltage is:
flowing through the winding in the rated operating mode by the resistance of the
winding at the reference operating temperature.
c) The iron loss of each part of the excitation device can be calculated according to
the design value.
5.4.3.6 I2R loss of auxiliary winding:
It is calculated by multiplying the square of the current flowing through the winding in
the rated operating mode by the resistance of the winding at the reference operating
temperature.
5.4.4 The stray loss may be determined by the following method
5.4.4.1 Short-circuit method
Short-circuit the armature winding of the tested motor and drag it to the rated speed
by the prime mover. The prime mover should be the analyzed motor or other prime
mover (such as dynamometer) that can accurately measure or calculate its output
power. Adjust the excitation current so that the armature current is the rated value.
Determine the DC resistance Ra (Ω) of the armature winding; the DC resistance is
measured immediately after the test. Subtract the mechanical loss PfN (kW) of the
tested motor and the I2R loss of the armature winding from the input power Pin (that is,
the output power of the prime mover, kW) of the tested motor to obtain the stray loss
Pd (kW) at the rated armature current:
5.4.4.2 Over-excitation/under-excitation method
The tested motor is operated as a no-load motor, excited by an independent power
supply; and the armature winding is applied with a practically symmetrical rated voltage
at a rated frequency. After the bearing and brush friction losses are stable, the test can
be carried out. In the over-excitation and under-excitation modes, the motor adjusts
the excitation current so that the armature current is the rated value; read the armature
voltage, armature current, input power, excitation current and speed; and measure the
DC resistance of the armature winding (may be measured immediately after the test).
Subtract the constant loss and I2R loss of armature winding from the input power of
the tested motor to obtain the stray loss of the tested motor during over-excitation and
under-excitation operation; and take the average value as the stray loss of the motor.
If the armature current cannot be adjusted to the rated value in the under-excitation
mode, the stray loss measured in the over-excitation mode is allowed as the stray loss
of the tested motor.
R1 – winding resistance in the actual state, in Ω;
θ1 – winding temperature corresponding to measuring the R1 in the actual cold state,
in °C;
θ0 – cold medium temperature at the end of the test, in °C.
6.1.1.2 Non-copper windings
For materials other than copper, use the reciprocal of the resistance temperature
coefficient of such material at 0°C to replace 235 in the above formula. For the
aluminum winding, unless otherwise specified, it shall adopt 225.
6.1.2 Thermometer method
This method measures the temperature by a thermometer attached to the surface
accessible to the motor. Thermometers include expansion thermometers (such as
mercury and alcohol thermometers, etc.), semiconductor thermometers, and non-
embedded thermocouples or resistance thermometers. During the measurement, the
thermometer shall be close to the surface of the measured point; use the insulating
materials to cover the measurement part of the thermometer; so that avoid the
influence from the surrounding cooling medium. As for the places with strong
alternating magnetic fields, the mercury thermometers cannot be used.
6.1.3 Embedded temperature detector method
This method measures the temperature by a temperature detector (such as a
resistance temperature detector, thermocouple or semiconductor thermal element)
embedded in the motor. The temperature detector is embedded in the motor, during
the manufacturing process, where it cannot be touched after the motor is made.
When measuring the resistance of an embedded resistance thermometer, the size of
the measurement current and the time for the current passing through shall be
controlled, so that the resistance value does not change significantly due to the heating
caused by the measurement current.
6.2 Determination of cooling medium temperature during temperature rise test
6.2.1 For motors (open motors or closed motors without a cooler) cooled by ambient
air or gas, the temperature of ambient air or gas shall be measured by several
thermometers, which shall be distributed in different places around the motor; at the
distance about (1~2) m from the motor. The ball is at half of the height of the motor;
and shall prevent all effects from radiation and airflow.
For motors with forced ventilation or closed-circuit circulating and cooling system, the
temperature of the cooling medium shall be measured at the air inlet of the motor.
For the motor with winding adopts water-inner-cooled method, take the temperature of
the incoming water as the temperature of the winding cooling medium.
For the non-water directly cooled iron core and other parts, take the temperature of the
intake air as the temperature of its cooling medium.
6.2.2 Determination of cooling medium temperature at the end of the test
The temperature of the cooling medium at the end of the test shall be the average
value of several thermometer readings measured at equal intervals during the last
quarter of the test.
6.3 Determination of the temperature of each part of the motor during the
temperature rise test
6.3.1 Determination of winding temperature
The motor winding temperature may be measured by the resistance method or the
embedded temperature detector method; but when the resistance method is used, the
resistance in cold and hot states must be measured at the same outlet end. For the
occasions where neither the embedded temperature detector method nor the
resistance method may be used, the thermometer method may be used. This method
is also applicable to the occasions specified in 7.6.1a), b), c), d) of GB 755-2000.
6.3.2 Determination of excitation winding temperature
When measuring the temperature of the excitation winding by the resistance method,
the voltage shall be measured on the slip ring.
6.3.3 Determination of temperature on excitation device winding and auxiliary
winding
Adopt resistance method and thermometer method.
6.3.4 Determination of temperature of stator iron core
The temperature shall be measured by the temperature detector when using the
embedded temperature detector; otherwise, use a thermometer (no less than two for
large and medium-sized motors) to measure; and take the highest value as the
temperature of the iron core.
6.3.5 Determination of the temperature of slip ring, pole shoe and damping
winding
Use a thermometer or spot thermometer to measure immediately after the motor stops.
6.3.6 Measurement of temperature of bearings and sealing-tiles
Self-Excited Constant Voltage
7.1 Determination of steady-state voltage regulation
7.1.1 Inspect the voltage setting range
7.1.1.1 Inspect the voltage setting range at no-load
During the inspection, the generator is no-load, in a cold or hot state, its speed is the
value specified in the standard of this type of motor. Adjust the voltage setting device;
determine the maximum and minimum value of the generator voltage; this range is the
generator’s voltage setting range in the cold or hot state at no-load.
7.1.1.2 Inspect the voltage setting range at full-load
During the inspection, the generator shall maintain the full load power and the power
factor during rated operation. The speed is the rated speed. Respectively, in the cold
and hot states of the generator, adjust the voltage setting device; and determine the
maximum and minimum voltage of the generator. This range is the generator’s voltage
setting range in the cold or hot state at full-load.
7.1.2 Determination of steady-state voltage regulation
The determination of the steady-state voltage regulation of the generator shall be
carried out in the cold or hot state according to the voltage, power factor and speed
specified in the standard.
Before the test, the generator is no-load, adjust the speed to the specified value. Adjust
the voltage setting device to set the voltage within the specified voltage regulation
range. For the uncontrollable phase compound excitation generator, it is allowed to
adjust the load and power factor to the rated values before the measurement; and then
gradually reduce the load to zero; and then repeatedly set the voltage within the
voltage regulation range. During the test, the voltage regulating device shall be
constant. During the test, keep the power factor unchanged; gradually increase the
three-phase symmetrical load from zero to the rated power, and then reduce the rated
power to zero. Measure the voltage at each point. The load change from point to point
is about 25% of the rated power; and the measurement point may be reduced as
appropriate during the inspection test.
According to the different types of generator excitation systems and different operation
modes, the steady-state voltage regulation may be calculated by Formula (42) or (43);
and the specific selection is stipulated by the standard of this type of motor.
8 Determination of Torque and Moment of Inertia
8.1 Determination of locked-rotor current and locked-rotor torque
8.1.1 Locked-rotor test
Before the test, apply a low voltage to determine the rotor position corresponding to
the maximum locked-rotor current and minimum locked-rotor torque, and block the
rotor. During the test, the wiring method of the motor excitation circuit shall be
consistent with the starting wiring method in actual use. The starting resistance value
required to be connected in the excitation circuit should be 10 times the resistance
value of the excitation winding when it is not specified in the technical file of the tested
motor. The armature winding of the tested motor shall be connected to the power
supply with rated frequency, adjustable actually-balanced voltage. When the power
supply voltage is below 20% of the rated value, connect the tested motor; and then
increase the power supply voltage as soon as possible so that the armature current is
about 200% (for small-size motor, and when tested by the motor’s automatic testing
device, the current may be larger) of the rated value. Quickly read three-phase line
voltage, three-phase line current, input power or torque (when directly measured) at
the same time. In order to avoid overheating of the motor, the test must be carried out
quickly. Then gradually reduce the power supply voltage (at this time, the frequency
should remain rated), totally read 8 ~ 9 points in the same way as above. Measure and
take the readings for no less than 4 points from the maximum current to the rated
current. If it is limited to the fact that the device cannot measure the torque, after
reading the test data of the last point and cutting off the power, immediately measure
the DC resistance value of the armature winding.
8.1.2 Determination of locked-rotor current and locked-rotor torque
According to the test data, draw the relationship curve of the average value of the
three-phase current against the average value of the three-wire voltage, as shown in
Figure 11. Extend the place of the highest voltage along the straight-line part of the
curve, intersecting the horizontal axis at the voltage point of U'.
TM – the obtained electromagnetic torque at the slip ratio of s = 0.05, in N • m.
The nominal value tpin of the nominal pull-in torque shall be calculated as per the
following formula:
If the point with a slip ratio of 0.05 during the test is not easy to establish accurately,
the load of the tested motor may be adjusted so that take 4 to 5 points with the slip
ratio around 0.05. Calculate the torque according to the above method, and draw the
curve of torque reverse slip. Determine the torque value from the curve at a slip ratio
of 0.05.
8.2.2 Acceleration method
The tested motor is connected to a stable power supply with a rated frequency and
adjustable actually-balanced voltage; so that enable the motor to start as a no-load
motor. The power supply voltage shall be adjusted to enable the motor to travel from
30%nN to nN for approximately 1.5min. During acceleration, the power supply voltage
and frequency remain unchanged. If the minimum voltage at which the motor can start
from a stationary state does not meet the above requirements, the power supply
voltage shall be further reduced until the above requirements are met. However, at this
time, the motor shall be started by other methods (for example, start with the
assistance of a crane or start with a higher voltage, then cut off the power to reduce
the speed of the motor, and when the motor speed drops below 30%nN, then add the
required voltage to test, etc.). In the speed range of 30%nN ~ 80%nN, measure the
speed once every (5~10) s and record the time. It shall be recorded every (3~5) s
within the speed range of 80%nN ~ 100%nN. During the test, pay attention to whether
the motor is overheated.
When using a fast recorder to test, the time to accelerate to full value may be faster
than the above provisions.
From the test data, make a curve of speed versus time, as shown in Figure 13.
Calculate the curve slope at 95%nN. This slope shall be determined by the
following method: take point a at 95%nN on the curve as the center; take the two points
b and c (the ordinate of point b should not exceed nN) at the same distance from point
a on the curve. The difference between the ordinates of these two points is Δn; the
difference between the abscissas of these two points is Δt; and the calculated curve
slope is .
shall be determined.
In the event of a sudden short circuit, no one is allowed to stay near the tested motor,
short circuit switch and lead (as short as possible) to ensure personal safety.
During the test, the motor shall be close to the operating temperature. If there are no
other provisions, the test shall be carried out under no-load motor excitation (separate-
excitation) corresponding to 1.05 times the rated voltage. The short circuit lasts for 3s.
After eliminating the short circuit, it shall not produce harmful deformation and can be
subject to the withstand voltage test.
10 Negative Sequence Current Withstand Capability
Test
The negative sequence current withstand capability test shall be carried out according
to the method specified in JB/T 8445.
11 Determination of Dynamic Characteristics of Stator
Winding Ends
The dynamic characteristics of the stator winding end are determined according to the
method specified in JB/T 8990.
12 Determination of Parameters (this Clause
Equivalently Adopt IEC 60034-4)
12.1 Description
12.1.1 During the test, the wiring method of the winding shall be the same as that
during normal operation.
The determination of various parameters is based on the consideration of star
connection of the armature winding (unless a special connection is specified, such as
an opening triangle). If the armature winding is actually connected in a triangle, the
parameters measured according to this Clause correspond to an equivalent star
winding.
12.1.2 All parameters and characteristics shall be expressed by per-unit values, at this
These time constants assume that certain components of related parameters (voltage,
current, etc.) decay as per the exponential curve. If the curve drawn by the actually-
measured components does not simply decay according to the exponential curve, for
instance, the actual curve of a solid rotor motor, the time constant shall generally be
understood as the time required by such component decays from the initial value to
the initial value of 1/ε ≈ 0.368. The exponential decay curve corresponding to these
time constants shall be regarded as an equivalent curve to replace the actual
measurement curve.
12.1.5 The parameters of the synchronous motor vary with the degree of saturation of
the magnetic circuit. In actual calculations, both saturated and unsaturated values are
used.
If there is no other explanation, in this Clause, except that the synchronous reactance
is not defined as the saturated reactance, the "saturated value" of other reactance and
resistance is taken as the value at its rated armature voltage; and the "unsaturated
value" is taken as its value at its rated (armature) current.
The rated (armature) voltage value of the parameter corresponds to the magnetic state
of the motor when the armature winding is suddenly short-circuited from the no-load
rated voltage operation of the motor at the rated speed.
The rated (armature) current value of the parameter corresponds to the situation when
determining the fundamental component of the armature current of this parameter is
equal to the rated current.
12.2 Determine parameters by no-load saturated characteristics and three-phase
steady-state short-circuit characteristics
12.2.1 The direct-axis synchronous reactance is determined by the no-load saturated
characteristics and three-phase steady-state short-circuit characteristics; taking the
ratio OF the no-load voltage value on the air-gap line TO the steady-state short-circuit
current value on the short-circuit characteristics under the same excitation current
(Figure 15).
The Xd value thus determined is an unsaturated value.
12.2.2 The short-circuit ratio is determined by the no-load saturated characteristic and
the three-phase steady-state short-circuit characteristic; taking the ratio OF the
excitation current value corresponding to the rated voltage on the no-load saturated
characteristic TO the excitation current value corresponding to the rated current on the
short-circuit characteristic (Figure 15).
PG is the positive sequence armature resistance voltage drop at rated current; and EP
is the excitation current component that the no-load voltage required to increase the
PG. Measure KL along the arc of FKB to make its length equal to EP. The length of
OL is the required excitation current.
When the tested motor is operating as a motor, the positive sequence armature
resistance voltage drop shall be measured from point E downward; and point L shall
be measured on the left side of point K.
If there is no excitation current corresponding to the rated voltage and rated current at
zero power factor, when using the Swedish diagram, the following method may be
used to determine its value. Add the voltage drop αxa at the rated armature current to
the rated armature voltage along the ordinate axis (see point H in Figure 17).
Make a straight-line from point H parallel to the abscissa axis; and intersect the no-
load characteristic at point H. Make a perpendicular line from point H to the abscissa
axis and intersect at point D (Figure 17). From point D, add the vector ifa (the length of
it is DB) along the abscissa axis. In this way, the excitation current expressed by the
length of OB is the current required when drawing by the Swedish diagram.
12.9 Reverse excitation test
During this test, the motor is connected in parallel with the power grid and runs at no-
load. The excitation current steadily decreases to zero; changes its polarity; and then
gradually increases until the motor slides by one pole distance. During the test,
measure the voltage, armature current and excitation current until the motor starts to
slide.
12.10 Determine Xq by reverse excitation test
When determining Xq by the inverse excitation test, use the following formula (per-unit
value or physical value) to determine:
Where:
(e) - no-load potential corresponding to the excitation current ifr when the motor slides
by one pole distance; it is determined by the linearized no-load characteristic passing
the point corresponding to the instantaneous voltage of the glide (Figure 21);
ur - instantaneous voltage at slide;
xd - direct-axis synchronous reactance determined by the same linearized no-load
saturated characteristic.
transformer to measure the short-circuit current. The latter is applied when only the AC
current component is involved; and the initial value of the super-transient component
of the short-circuit current shall be selected to be in the linear part of the transformer
characteristics.
Connect the hollow transformer to the oscillograph through the integrator amplifier. If
only the maximum aperiodic and periodic values of the short-circuit current component
need to be determined, then an integral oscilloscope galvanometer may be used.
The total resistance of the measuring instrument and the leads connected to the
secondary loop of the current transformer shall not exceed the allowable rated value
of the transformer.
Before the short circuit, instantaneously measure the motor terminal voltage, excitation
current and excitation winding temperature.
In order to obtain the parameters corresponding to the unsaturated state of the motor,
this test shall be completed at several different armature voltages of 0.1 ~ 0.4 times
the rated value. Each test obtains various parameters and draws the relationship curve
between the initial values of their AC transient or super-transient armature currents.
From this relationship, various parameters required for rated armature current are
obtained.
In order to obtain the parameters corresponding to the saturated state of the motor,
the test shall be carried out when the terminal voltage of the motor is the rated value
before short-circuiting the armature winding.
If the sudden short circuit cannot be under the rated voltage, it is recommended to
carry out the test under several different armature voltages (such as 0.3, 0.5 and 0.7
times the rated voltage) and obtain various parameters for each test. Draw their
relationship curve to the open circuit voltage before short circuit; and use the
extrapolation method to obtain the approximate value of the parameter under the rated
armature voltage.
In order to determine the motor parameters, the waveforms of each phase’s armature
current and excitation current shall be recorded.
The continuous recording time of the oscillograph after short circuit shall be no less
than Td'+ 0.2s. After the stable working condition is established, the oscillograph shall
be started to record the stable value. The final value used for calibration shall be
measured by a meter. If the current is known to decay exponentially according to a test
of a similar motor, the oscillograph may be made shorter.
Use the three-phase short-circuit oscillogram to obtain the change relationship
between the aperiodic and periodic armature current components of each phase and
time; that is, it is obtained from half of algebraic sum and half of algebraic difference of
the ordinates of the upper and lower envelop lines of the each phase’s short-circuit
current.
The periodic component of the armature current during a short circuit is calculated by
the arithmetic average of the periodic components of the three phase currents.
To obtain the transient (Δik') and super transient (Δik") components, subtract the
steady-state short-circuit current value i(∞) from the curve of the armature current
periodic component curve. The remainder is the sum of Δik'+ Δik"; draw it on a semi-
logarithmic coordinate line. The drawn line may be a straight-line or a curved-line.
a) When the lower half of the line is a straight-line (equivalent to an exponential
function), extrapolate this straight-line to t = 0 to obtain the initial value Δik'(0) of
the transient component in the short-circuit current (Figure 23).
b) When the lower half of the line is a curved-line, firstly, take the amplitude of the
current iA corresponding to the time OA'; OA' is 0.2s or the time when the
transient effect starts and can be ignored. Then measure the time OB'
corresponding to iB = iA/ε. The time constant Td' is taken as (OB'-OA') s. The
straight line passing through the two current values of iB and iA is the isoline of
Δik'. When this line is extrapolated to t=0, the initial value Δik'(0) of the short-
circuit current transient component shall be obtained (Figure 24).
The super transient short-circuit current component is defined as the difference
between the Δik'+ Δik" curve and the Δik' equivalent decay curve. The change of the
super transient current component with time is also drawn on semi-logarithmic
coordinate paper (Figure 23).
Draw the relationship between the aperiodic current component of each phase and
time on semi-logarithmic coordinate paper. Extrapolate each curve to t=0 to get the
initial value of each corresponding current.
In order to obtain the maximum possible value of the aperiodic component, draw the
initial value of the aperiodic component of each phase obtained by extrapolation into
three vectors (Figure 25) from the origin; thereof, the largest vector is in the middle;
and the other two vectors form an angle of 60° with it. Draw a vertical line from the end
of each vector. The three vertical lines intersect each other to form a triangle. Introduce
a vector from the origin to the center of the triangle. This vector is the maximum
possible value of the aperiodic component, which is equal to the initial value of the
amplitude of the periodic component.
not be considered when determining the armature short-circuit time constant.
If the armature current is measured by a non-inductive shunt in a sudden short-circuit
test, it is allowed to determine the armature short-circuit time constant by the decay of
the aperiodic armature current component.
12.16.6 When using the three-phase sudden short-circuit test to determine the
maximum possible instantaneous initial short-circuit current value, it is equal to the
sum of the periodic component and the aperiodic component at half a cycle after the
short circuit instant.
The value of the periodic component at this instant is equal to the sum of the steady-
state component, the transient component and the super-transient component of the
sudden short-circuit current.
The last two compo......
Related standard:   GB/T 7409.2-2020  GB/T 7064-2017
Related PDF sample:   GB/T 22669-2008
   
 
Privacy   ···   Product Quality   ···   About Us   ···   Refund Policy   ···   Fair Trading   ···   Quick Response
Field Test Asia Limited | Taxed in Singapore: 201302277C | Copyright 2012-2020