Chinese Standards Shop Partner of Google-Books Database: 169760 (Nov 9, 2019)
 HOME   Quotation   Tax   Examples Standard-List   Contact-Us   View-Cart
  

DL/T 911-2004

Chinese Standard: 'DL/T 911-2004'
Standard IDContents [version]USDSTEP2[PDF] delivered inStandard Title (Description)StatusRelated Standard
DL/T 911-2004English75 Add to Cart 0--15 minutes. Auto immediate delivery. Frequency response analysis on winding deformation of power transformers Obsolete DL/T 911-2004

 DL/T 911-2004 -- Click to view a PDF In 0~10 minutes time, full copy of this English-PDF will be auto-immediately delivered to your email by our cloud-server.  
Detail Information of DL/T 911-2004; DL/T911-2004; DLT 911-2004; DLT911-2004
Description (Translated English): Frequency response analysis on winding deformation of power transfermers
Sector / Industry: Electricity & Power Industry Standard (Recommended)
Classification of Chinese Standard: F24
Classification of International Standard: 27.100
Word Count Estimation: 13,000
Date of Issue: 2004-12-14
Date of Implementation: 2005-06-01
Drafting Organization: China Electric Power Research Institute
Administrative Organization: High voltage test power industry technical standards technical committee
Regulation (derived from): Development and Reform Bulletin (04/ 75)
Summary: This standard specifies the method of detection using frequency response analysis transformer winding deformation of the basic requirements. This standard applies to 6kV and above voltage level of power transformers and other special purpose transformers.

DL/T 911–2004
911-2004)
ICS 27.100
F 24
File No.. 15182-2005
PROFESSIONAL STANDARD OF THE PEOPLE’S
REPUBLIC OF CHINA
Frequency Response Analysis on Winding
Deformation of Power Transformers
电力变压器绕组变形的频率响应分析法
ISSUED ON. DECEMBER 14, 2004
IMPLEMENTED ON. JUNE 1, 2005
Issued by. National Development and Reform Commission of the
People's Republic of China
Table of Contents
FOREWORD ... 2
1 SCOPE ... 3
2 NORMATIVE REFERENCES ... 3
3 TERMS AND DEFINITIONS ... 3
4 TESTING THEORY ... 5
5 REQUIREMENTS OF TESTING INSTRUMENT ... 6
6 TEST METHOD ... 8
7 ANALYTICAL JUDGMENT OF WINDING DEFORMATION ... 9
ANNEX A (NORMATIVE) AUXILIARY JUDGMENT ON DEFORMATION OF TRANSFORMER WINDING
THROUGH THE CORRELATION FACTOR R ... 14
ANNEX B (INFORMATIVE) TYPICAL AMPLITUDE FREQUENCY RESPONSE CHARACTERISTICS CURVE
OF DEFORMATION OF TRANSFORMER WINDING ... 16
REFERENCES AND ORIGINAL CHINESE DOCUMENTS ... 20
Foreword
In accordance with the requirements of the document - "Notice on confirming the
formulation and revision planning of power industry standards in 1999" (Guo Jing Mao
Dian Li [1999] No.40) issued by the Former State Economic and Trade Commission, this
Standard is formulated, with the objective of regulating and guiding field application of
the frequency response analysis on winding deformation of power transformer.
Frequency response analysis, used to test the deformation of transformer winding, has
advantages in high testing sensitivity and convenient in field service; and does not
require transformer hood suspending. It has been widely used in the power industry.
Annex A is normative and Annex B is informative in this Standard.
This Standard is proposed by the China Electricity Council (CEC).
The technical committee for standardization of high voltage test technology in power
sector governs this Standard and is in charge of the explanation.
Drafting organizations. China Electric Power Research Institute (CEPRI), Guangdong
Power Experimental Research Institute, Fujian Power Test & Research Institute, Anhui
Electric Power Research Institute, North China Electric Power Research Institute,
Wuhan High Voltage Research Institute
Chief drafting staffs. Wang Sheng, Gao Keli, Lin Chunyao, Ouyang Xudong, Zhang
Konglin, Yu Guogang, He Hongming, Ma Jixian, Mei Gang
Frequency Response Analysis on Winding
Deformation of Power Transformers
1 Scope
This Standard specifies the basic requirements in the frequency response analysis on
deformation of transformer winding.
This Standard is applicable to power transformers of 6kV or higher voltage class, and
other transformers for special purpose.
2 Normative References
The following standards contain provisions which, through reference in this text,
constitute provisions of this Standard. For dated reference, subsequent modifications
(excluding corrected contents) or revisions do not apply to this Standard. However, all
parties reach to agreement according to this Standard are encouraged to study whether
the latest edition of these documents is applicable. For undated references, the latest
edition of the normative document referred to applies to this Standard.
GB 1094.1 Power transformers - Part 1. General (eqv IEC 60076-1. 1993)
GB 1094.5 Power transformers - Part 5. Ability to withstand short circuit (neq IEC
60076-5. 1976)
DL/T 596 Preventive test code for electric power equipment
3 Terms and definitions
For the purpose of this Standard, the following terms and definitions shall apply.
3.1
Winding deformation
It is referred to axial or radial dimensional variation of power transformer winding caused
under mechanical force or electro-dynamical action, and usually appears as partial
deformation, hunching or displacement of winding. When a transformer is suffered from
the short-circuit current rush or crash in transportation, winding deformation may happen.
This will directly affect the safe operation of transformer.
3.2
Dual-port network
It is referred to network having a pair of input ports and a pair of output ports. The
network - consisted of linear resistance, inductance (including mutual inductance) and
capacitive components, and without independent power supply inside - is called as
active linear dual-port network. When the frequency is higher, the transformer winding
may be regarded as active linear dual-port network.
3.3
Transfer function
It is referred to the output-input ratio of passive dual-port network, expressed by Laplace
transformation. The pole and zero distribution of the transfer function closely relate to
built-in components’ parameters, connecting mode and port-connecting-impedance of
dual-port network.
3.4
Frequency response
It is referred to the relation between transfer function H(jω) and angular frequency ω of
the network, under the sine stable state. Usually, the relation of H(jω) amplitude value
changing with ω is called as amplitude frequency response, and the relation of H(jω)
phase changing with ω is called as phase frequency response.
3.5
Sweeping frequency
6 Test Method
6.1 The testing for deformation of transformer winding shall be conducted before all
direct-current test items or after full electric discharge of the winding. The windings of a
transformer shall be tested one by one according to the wiring requirement and
connection mode, and the amplitude frequency response characteristics curves shall be
recorded respectively.
6.2 Wiring requirement
6.2.1 Before testing, all leading wires connected with the tip of the transformer
bushing shall be dismantled, and KEEP the dismantled leading wires as far as possible
from the transformer bushing. If the leading wires connected with the transformer
bushing cannot be dismantled, the tap at the end of the bushing may be used as
response-port for testing, however this must be noted, and the test result under this
condition must be compared with the ones under similar condition.
6.2.2 The amplitude frequency response characteristics of the transformer winding is
related to the position of tap-switch, it should be tested at the highest tap position, or it
shall be guaranteed that the tap-switch is at the same position for each testing.
6.2.3 Because the testing signal is weak, all wirings shall be stable, reliable and of
minimized contact resistance.
6.2.4 The earth wires of the two signal detection ports shall be connected reliably
onto the obvious ground port (e.g. iron-core’s grounding port) on the transformer case.
The earth wire shall be as short as possible and without enwinding.
6.3 Wiring mode
Signal excitation (input) port and response (testing) port shall be selected according to
the mode indicated in Figure 2, so that conducting the standardized management on the
testing results in future.
variation (change) of winding inductance will result in the obvious-shift of the wave crest
or wave trough position at low frequency stage in its frequency response characteristic
curve. For most of transformers, the response characteristic curve of three-phase
windings at low-frequency band shall be highly similar. The root cause must be found out
if there is any difference.
7.4.3 The obvious variation in wave crest or wave trough positions at
medium-frequency band (100kHz ~600kHz ) in amplitude frequency response
characteristics curve usually indicates the local deformation of the winding like twisting
and hunching. There are many wave crests and wave troughs in the amplitude
frequency response characteristics curve within this frequency range. They can
sensitively reflect the change of distributed inductance and capacitance of the winding.
7.4.4 The obvious vari......
Related standard:   DL/T 911-2016  DL/T 913-2005
   
 
Privacy   ···   Product Quality   ···   About Us   ···   Refund Policy   ···   Fair Trading   ···   Quick Response
Field Test Asia Limited | Taxed in Singapore: 201302277C | Copyright 2012-2019