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GB/T 38954-2020 PDF in English


GB/T 38954-2020 (GB/T38954-2020, GBT 38954-2020, GBT38954-2020)
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GB/T 38954-2020: PDF in English (GBT 38954-2020)

GB/T 38954-2020
GB
NATIONAL STANDARD OF THE
PEOPLE’S REPUBLIC OF CHINA
ICS 27.070
K 82
Hydrogen fuel cell power system for unmanned aerial
vehicles
ISSUED ON: JUNE 02, 2020
IMPLEMENTED ON: DECEMBER 01, 2020
Issued by: State Administration for Market Regulation;
Standardization Administration of PRC.
Table of Contents
Foreword ... 4 
1 Scope ... 5 
2 Normative references ... 5 
3 Terms and definitions ... 6 
4 General requirements ... 8 
4.1 General ... 8 
4.2 General safety requirements ... 10 
4.3 Appearance and structure ... 11 
4.4 Other general technical requirements ... 11 
5 Technical requirements ... 12 
5.1 Start-up time ... 12 
5.2 Time to reach rated power ... 12 
5.3 Rated output power ... 12 
5.4 Power overload rate ... 12 
5.5 Output voltage range ... 12 
5.6 Power efficiency ... 12 
5.7 Startup/shutdown method ... 13 
5.8 Shutdown time... 13 
5.9 Continuous operation time ... 13 
5.10 Noise ... 13 
5.11 Vibration resistance ... 13 
5.12 Electromagnetic compatibility limits ... 13 
5.13 Data transmission... 14 
5.14 Hydrogen supply flow ... 14 
5.15 Fuel concentration in cabin ... 14 
5.16 Limitation of fuel concentration in exhaust gas ... 14 
5.17 Degree of protection of cabin ... 14 
5.18 Service life ... 14 
5.19 Hydrogen leakage rate ... 15 
5.20 Alarming function and monitoring function ... 15 
6 Test method ... 16 
6.1 Test preparation ... 16 
6.2 Test of start-up time ... 16 
6.3 Test of time to reach rated power ... 17 
6.4 Test of rated output power ... 17 
6.5 Test of power overload rate ... 17 
6.6 Test of output voltage range ... 17 
6.7 Electric efficiency test ... 17 
6.8 Test of startup/shutdown mode ... 18 
6.9 Test of shutdown time ... 18 
6.10 Test of continuous operation time ... 18 
6.11 Noise test ... 18 
6.12 Vibration resistance test ... 19 
6.13 Test of electromagnetic compatibility limit ... 19 
6.14 Data transmission test ... 20 
6.15 Hydrogen flow test... 20 
6.16 Test of fuel concentration in cabin ... 20 
6.17 Fuel concentration test in exhaust gas ... 21 
6.18 Cabin protection level test ... 21 
6.19 Service life test ... 21 
6.20 Hydrogen leakage rate test ... 21 
6.21 Test of alarming and monitoring function ... 23 
7 Marking, packaging, transportation ... 23 
7.1 Marking ... 23 
7.2 Packaging ... 24 
7.3 Documentation ... 24 
Appendix A (Informative) Hydrogen cylinder requirements ... 25 
Appendix B (Informative) Typical life test method ... 26 
Foreword
This standard was drafted in accordance with the rules given in GB/T 1.1-2009.
This standard was proposed by China Electrical Equipment Industry
Association.
This standard shall be under the jurisdiction of the National Fuel Cell and Flow
Battery Standardization Technical Committee (SAC/TC 342).
Drafting organizations of this standard: Xinyan Hydrogen Energy Technology
Co., Ltd., Shouhang Guoyi (Wuhan) Technology Co., Ltd., Beijing Institute of
Electrical Technology and Economics of Mechanical Industry, Dalian Institute of
Chemical Physics of Chinese Academy of Sciences, Xinyuan Power Co., Ltd.,
Wuhan University of Technology University, Shanghai Shenli Technology Co.,
Ltd., Aerospace New Long March Electric Vehicle Technology Co., Ltd.,
Shanghai Panye Hydrogen Energy Technology Co., Ltd., China Quality
Certification Center, Wuhan Zhongyu Power System Technology Co., Ltd.,
Dongguan Zhongchuang New Energy Technology Co., Ltd., Beijing Shangdian
Technology Co., Ltd., Shanghai Institute of Quality Supervision and Inspection
Technology, Wuxi City Product Quality Supervision and Inspection Institute,
Guangdong Hezhide Energy Technology Co., Ltd., Beijing Yihuatong
Technology Co., Ltd., Shanghai Hengjin Power Technology Co., Ltd., Shanghai
Boxuan Energy Technology Co., Ltd., Zhejiang Gaocheng Green Energy
Technology Co., Ltd.
The main drafters of this standard: Qi Zhigang, Zhang Liang, Pan Mu, Yu
Hongmei, Zhou Bin, Xing Danmin, Lu Chenyu, Jin Yinshi, Dong Hui, Wang
Gang, Li Songli, Chen Yao, Huang Ping, Zhao Feng, Chen Wei, Xu Weiqiang,
Liu Ran, Hu Lei, Tian Binglun, Hou Xiangli.
Hydrogen fuel cell power system for unmanned aerial
vehicles
1 Scope
This standard specifies the general requirements, technical requirements, test
methods, marking, packaging and transportation requirements for hydrogen
fuel cell power systems for unmanned aerial vehicles.
This standard applies to fuel cell power systems that use compressed hydrogen
as fuel to provide power and non-powered electricity for unmanned aerial
vehicles which have an unloaded mass not exceeding 116 kg and a maximum
take-off mass not exceeding 150 kg.
2 Normative references
The following documents are essential to the application of this document. For
the dated documents, only the versions with the dates indicated are applicable
to this document; for the undated documents, only the latest version (including
all the amendments) are applicable to this standard.
GB/T 191 Packaging - Pictorial marking for handling of goods
GB/T 2893.2-2008 Graphical symbols - Safety colors and safety signs - Part
2: Design principles for product safety labels
GB/T 4208-2017 Degrees of protection provided by enclosure (IP code)
GB/T 4980-2003 Determination of sound level for noise emitted by
displacement compressors
GB/T 15329-2019 Rubber hoses and hose assemblies - Textile-reinforced
hydraulic types for oil-based or water-based fluids - Specification
GB/T 17626.2-2018 Electromagnetic compatibility - Testing and
measurement techniques - Electrostatic discharge immunity test
GB/T 17626.3-2016 Electromagnetic compatibility - Testing and
measurement techniques - Radiated, radio-frequency, electromagnetic field
immunity test
GB/T 20042.1 Proton exchange membrane fuel cell - Part 1: Terminology
GB/T 20438.1 Functional safety of electrical/electronic/programmable
electronic safety-related systems - Part 1: General requirements
GB/T 20972.1 Petroleum and natural gas industries - Material for use in
H2S-containing environments in oil and gas production - Part 1: General
principles for selection of cracking resistant materials
GB/T 28816 Fuel cell - Terminology
GB/T 36288-2018 Fuel cell electric vehicles - Safety requirement of fuel cell
stack
YD/T 122 Nameplates of products for posts and telecommunications
industry
3 Terms and definitions
The terms and definitions as defined in GB/T 20042.1 and GB/T 28816 as well
as the following terms and definitions apply to this document.
3.1
Unmanned aerial vehicle
An unmanned aerial vehicle controlled and managed by a remote-control
system (including remote control or autonomous flight).
3.2
Fuel cell power system for unmanned aerial vehicle
A fuel cell power system that provides power and non-power electricity for
unmanned aerial vehicles.
Note: In this standard, fuel cell power systems include fuel cell systems
(including auxiliary energy storage modules) and fuel storage modules and
fuel supply modules (both collectively referred to as fuel systems) that
provide hydrogen to it.
3.3
Start-up time
The duration of the fuel cell power system from the moment of power-on (the
moment when the manual power-on starts from the starting action) to the
moment when there is net electric power output.
3.4
Shut-down time
The length of time from the moment when the fuel cell power system
receives the shutdown instruction (the moment when the manual shutdown
starts from the shutdown action) to the moment when all components stop
working.
3.5
Rated output power
The maximum continuous output power of the fuel cell power system under
normal operating conditions as specified by the manufacturer.
3.6
Output voltage range
Under the normal operating conditions specified by the manufacturer, the
output voltage range of the fuel cell power system from startup, operation to
shut down.
3.7
Continuous running time
Under normal operating conditions specified by the manufacturer, the
continuous time that the output voltage of the fuel cell power system does
not exceed the output voltage range when operating at the rated output
power.
3.8
Fuel storage module
Pressure device used to store hydrogen (such as hydrogen cylinder).
3.9
Fuel supply module
The assembly of all the components, pipe connections and controls which is
used to deliver hydrogen to the fuel cell hydrogen inlet, from the hydrogen
cylinder to the stack hydrogen inlet.
Note: The fuel supply module consists of some or all of the following
components: stop valve, filter (optional), solenoid valve (optional), pressure
reducing valve, fuse valve (optional), overflow valve (optional), pressure
relief valve (optional), one-way valve (optional), fuel filling interface, pressure
sensor, temperature sensor (optional), pressure gauge (optional), flow meter
(optional), electronic control device (optional) etc.
3.10
Hydrogen leakage ratio
The ratio of the amount of hydrogen leakage to the theoretical amount of
hydrogen required by the fuel cell power system at rated power.
3.11
Alarm
The function of transmitting the alarm status and fault status to the alarm
device and giving sound and light alarm.
4 General requirements
4.1 General
The schematic diagram of the boundary of the proton exchange membrane fuel
cell power system for unmanned aerial vehicle is as shown in Figure 1.
Input power
Vibration, wind,
rain, temperature,
humidity, etc.
Residual
heat
Vibration,
noise
Output
power
Drainage
water
Electromagnetic
disturbance Electromagnetic disturbance
Air
Water
Fuel
storage
module Thermal manageme
nt module
Internal
power
demand
Power
regulating
module
Auxiliary
energy
storage
module
Fuel
supply
module Fuel cell
module
Air supply
module
Water
manageme
nt module
Control
module
Ventilation
module
Figure 1 -- Schematic diagram of the boundary of the hydrogen fuel cell
power system for unmanned aerial vehicles
According to actual needs, the fuel cell power system for unmanned aerial
vehicle consists of some or all of the following modules:
- Fuel cell module (mandatory): It is composed of one or more stacks,
electrical connection devices that transmit the electricity as generated by
the stacks, monitoring devices, etc.;
- Air supply module (mandatory): The general name of the device that
measures, regulates, pressurizes, or treats otherwise the air required by
the fuel cell power system;
- Fuel storage module (mandatory): A device for storing hydrogen;
- Fuel supply module (mandatory): The assembly of all components, pipe
connections and their controls from the hydrogen cylinder to the hydrogen
inlet of stacks which is used for storing hydrogen and transporting hydrogen
to the hydrogen inlet of the fuel cell;
- Control module (mandatory): A module composed of sensors, actuators,
valves, switches and logic elements, which is used to maintain the
parameters of the fuel cell power system within the manufacturer's setting
range without manual intervention;
- Thermal management module (optional): The relevant components which
provide cooling and heat dissipation functions to keep the interior of the fuel
cell power system in the normal temperature range, meanwhile recover
residual heat, heat the relevant components of the system during startup
when necessary;
- Water management module (optional): A module that manages the water
required or produced by the fuel cell system;
- Power regulating module: A module used to match the electric energy
generated by the stack module and the auxiliary energy storage module
with the specified electricity demand;
- Ventilation module (optional): A module that delivers air to the space around
the fuel cell power system through natural or mechanical methods;
- Auxiliary energy storage module (optional): The energy storage device
inside the system, which is used to store electrical energy, start the fuel cell
power system, cooperate with the fuel cell module to supply power to
internal or external loads.
4.2 General safety requirements
4.2.1 The design and manufacture of fuel cell power systems shall fully consider
the safety risks of various failures and/or accidents that may be encountered
during normal or abnormal use; take corresponding measures to avoid safety
risks or reduce safety risk to an acceptable degree.
4.2.2 For possible safety risks, the fuel cell power system shall provide safety
reminders or sound, light, electricity and other warning signals; provide
automatic and/or manual handling measures.
4.2.3 For the heating components of the fuel cell power system, it shall take
corresponding measures to avoid personal injury caused by contact with or
close to hot surface components.
4.2.4 The design of the fuel cell power system shall ensure that a single failure
of the system components will not be escalated. Methods to prevent failure
escalation include but are not limited to:
- Install protective devices (such as interlocking protective devices and
tripping devices) in the fuel cell power system;
- Set the protective interlock function of the circuit;
- Use proven technologies and components;
- Provide partial or complete redundant devices or diversify the protective
measures;
- Issue an alarm to the superior system of the fuel cell power system.
4.2.5 The main components that make up the fuel cell power system for
unmanned aerial vehicles shall meet the specific safety requirements of their
respective fields. For details, refer to the following documents:
- The safety of fuel cell modules shall be in accordance with the requirements
specified in GB/T 36288-2018;
- The control device components shall be designed in accordance with the
provisions of GB/T 20438.1;
- The hose and hose assembly shall meet the requirements of the type 1TE
hose in GB/T 15329-2019;
- Metal pipelines and their connecting parts shall meet the requirements of
GB/T 20972.1.
4.3 Appearance and structure
4.3.1 The appearance of the fuel cell power system shall be clean, free of
mechanical damage, free of cracks, stains and obvious deformation; there is
no rust on the interface contacts.
4.3.2 The accessible parts of the fuel cell power system shall not have sharp
edges and corners that may cause personal injury.
4.3.3 During the normal operation of the fuel cell power system, its parts and
their connectors shall be stable and reliable; there shall be no instability,
deformation, fracture or wear.
4.3.4 The communication interface, power interface, user interface, hydrogen
inlet and outlet of the fuel cell power system shall be clearly identified.
4.3.5 The positive and negative terminals and polarity of the fuel cell power
system shall be clearly identified for easy connection.
4.4 Other general technical requirements
4.4.1 Environmental requirements for the use of fuel cell power systems:
temperature: -5 °C ~ 40 °C; relative humidity: ≤ 100%; altitude: ≤ 3000 m.
4.4.2 The fuel cell power system shall be able to provide sufficient power for the
normal flight of the unmanned aerial vehicles.
4.4.3 In the case of normal transmission of communication signals, the fuel cell
power system itself or the communication system through the unmanned aerial
vehicles shall be able to communicate normally with the ground control system.
4.4.4 The main parameters of the fuel cell power system shall be able to be
monitored in real time.
4.4.5 In the case that the unmanned aerial vehicles and the ground control
system lose communication, the fuel cell power system shall be able to continue
to provide power for the unmanned aerial vehicles and execute the
predetermined plan.
4.4.6 The hydrogen cylinders in the fuel cell power system shall have detailed
filling records during use.
4.4.7 The minimum design burst pressure of the hydrogen cylinder in the fuel
cell power system and the design fatigue resistance counts of the hydrogen
cylinder shall meet the relevant requirements of the national standards; in the
absence of these standards, please refer to Appendix A.
5 Technical requirements
5.1 Start-up time
The start-up time of the fuel cell power system shall be less than 1 min.
5.2 Time to reach rated power
When the ambient temperature is higher than 0 °C, the time for the fuel cell
power system to reach the rated power shall be less than 1 min.
When the ambient temperature is -5 °C ~ 0 °C, the time for the fuel cell power
system to reach the rated power shall be less than 5 minutes.
5.3 Rated output power
The rated output power of the fuel cell power system shall not be lower than the
manufacturer's indicated value; at this power, the continuous operation time of
the fuel cell power system shall not be lower than the manufacturer's indicated
value.
In the specified minimum continuous operation time, the output power of the
fuel cell power system shall be maintained at ±5% of the nominal rated output
power.
5.4 Power overload rate
The fuel cell power system shall be able to continuously output more than 2
minutes at 150% of the rated output power.
5.5 Output voltage range
The output voltage of the fuel cell power system shall be within the output
voltage range of the fuel cell power system as indicated by the manufacturer.
5.6 Power efficiency
Under the rated power output, the power efficiency of the fuel cell power system
shall be greater than 40%.
5.7 Startup/shutdown method
The fuel cell power system shall have at least one of the following
startup/shutdown methods:
- Manual;
- Remote control;
- Automatic.
5.8 Shutdown time
The shutdown time of the fuel cell power system shall be less than 2 minutes.
5.9 Continuous operation time
The continuous operation time of the fuel cell power system used on the fixed-
wing unmanned aerial vehicle shall not be less than 6 h. The continuous
operation time of the fuel cell power system used on the multi-rotor unmanned
aerial vehicle shall not be less than 3 h. The continuous operation time can also
be determined according to the fuel cell power system’s purchase agreement.
5.10 Noise
Under the rated power output, the noise of the fuel cell power system shall not
exceed 78 dB.
5.11 Vibration resistance
Under normal operating conditions, the fuel cell power system shall be able to
resist vibration; keep its mechanical and electrical connections normal; the
hydrogen leakage rate shall meet the requirements in 5.19; the fuel
concentration in the cabin shall meet the requirements in 5.15.
5.12 Electromagnetic compatibility limits
The electrostatic discharge immunity limit of fuel cell power system shall meet
the requirements of test level 3 in GB/T 17626.2-2018. During the test, the
sample under test shall not be damaged, malfunction or change of state;
however, the indicator light is allowed to flash; the system shall work normally
after the test.
The radio-frequency electromagnetic field radiation immunity limit of the fuel
cell power system shall meet the requirements of test level 3 in GB/T 17626.3-
2016. After the test, the performance of the equipment shall not be permanently
damaged or degraded; the system shall be able to work normally.
5.13 Data transmission
The fuel cell power system shall have communication interfaces such as RS232,
RS485, CAN, etc.
5.14 Hydrogen supply flow
The stable hydrogen supply flow rate provided by the fuel system to the fuel cell
module shall reach the value as indicated by the manufacturer.
5.15 Fuel concentration in cabin
The fuel concentration in the fuel cell power system’s cabin shall be less than
50% of the lowest flammable limit (LFL).
5.16 Limitation of fuel concentration in exhaust gas
The continuous time for the fuel concentration in the exhaust gas of the fuel cell
power system to be greater than 50% LFL shall be less than 5 s.
5.17 Degree of protection of cabin
The protection level of the fuel cell power system’s cabin shall at least meet
IP53.
5.18 Service life
The cumulative operating time of the fuel cell power system shall not be less
than 500 h, or the number of startups and shutdowns shall not be less than 200.
5.19 Hydrogen leakage rate
The hydrogen leakage rate shall not exceed 0.5%.
5.20 Alarming function and monitoring function
5.20.1 Alarming function
When the following situations occur, the fuel cell power system shall be able to
provide users with warning functions:
- Hydrogen pressure is abnormal (for example, the hydrogen pressure at the
outlet of the hydrogen cylinder is lower than the specified minimum
pressure; the hydrogen pressure after the pressure reduction valve is lower
than the set minimum pressure or higher than the set maximum pressure);
- Output over/under voltage, low fuel cell module output voltage;
- The power output exceeds the overload protection setting value;
- The ambient temperature is too high/low;
- The temperature of the fuel cell module is too high;
- Low voltage of auxiliary energy storage module;
- The fuel concentration in the cabin is too high.
5.20.2 Monitoring function
The fuel cell power system shall have the following monitoring functions:
- Remote measurement: Remotely measure system output voltage, system
output current, auxiliary energy storage module’s voltage, fuel cell module’s
output voltage, fuel cell module’s output current, hydrogen cylinder’s
hydrogen pressure, fuel cell module’s inlet hydrogen pressure, fuel cell
module’s temperature, ambient temperature;
- Remote signaling: Remotely provide signals, including fuel cell module
over-temperature, low/high hydrogen pressure at the inlet of the fuel cell
module, fuel cell system’s output over/under pressure, fuel cell system
output’s overcurrent, low/high hydrogen pressure of hydrogen cylinder, low
voltage of auxiliary energy storage module, low/high ambient temperature;
- Remote control: System on/off.
6 Test method
6.1 Test preparation
6.1.1 General test requirements
According to the manufacturer's requirements, put the fuel cell power system in
a specific environment; connect the gas pipeline and the load. During the whole
test process, use an ammeter to measure the output current and a voltmeter to
measure the output voltage. The test data can be collected and saved in real
time; the sampling frequency is 1 time/s.
6.1.2 Test environment requirements
The altitude is not more than 1000 m; the ambient temperature is 5 °C ~ 40 °C.
If the altitude exceeds 1000 m in actual application, or the ambient temperature
exceeds 5 °C ~ 40 °C, the manufacturer shall consider the changes of some
parameters of the fuel cell power system.
6.1.3 Measuring instrument and accuracy
The main test measuring instruments and accuracy requirements are as shown
in Table 1.
Table 1 -- Measuring instruments and accuracy
Measuring instrument Unit Accuracy
Barometer kPa ±1.0% (full scale)
Humidity measuring instrument % Relative humidity ±3.0%
Temperature measuring instrument °C ±1.0
Pressure measuring instrument kPa ±1.0% (full scale)
Mass flow controller L/min ±1.0% (full scale)
Voltage measuring instrument V ±1.0% (full scale)
Current measuring instrument A ±1.0% (full scale)
Hydrogen concentration tester % (volume fraction) ±1.0% (full scale)
6.2 Test of start-up time
According to the manufacturer's requirements, place the fuel cell power system
in a specific environment; connect the gas pipeline and load. When everything
is ready, issue a startup command to the fuel cell power system; measure the
duration from the start command to the moment when the fuel cell power
system has net electric power output (unit: s).
6.3 Test of time to reach rated power
After the fuel cell power system is allowed to stand for 2 hours in the tested
ambient temperature, measure the time from the time after the startup of the
fuel cell system to the rated power output of the fuel cell power system.
6.4 Test of rated output power
Under the rated output power of the fuel cell power system as indicated by the
supplier, the continuous operation of the fuel cell power system is not shorter
than the continuous operation time identified by the supplier; the output voltage
of the fuel cell power system is recorded every second; its value shall not
exceed the output voltage range as indicated by the supplier at any time
throughout the test process.
6.5 Test of power overload rate
Make the fuel cell power system run at no less than 150% of the rated output
power as stated by the manufacturer. Monitor the continuous operation time of
the fuel cell power system in this state. After running for more than 2 minutes,
shut down the fuel cell power system according to the shutdown method
specified by the manufacturer.
6.6 Test of output voltage range
During the entire test process from 6.2 ~ 6.5, the output voltage of the fuel cell
power system is monitored and recorded at an interval of 1 s. In the whole
process from startup to shut down, the voltage range of the fuel cell power
system from low to high is the output voltage range of the fuel cell power system.
6.7 Electric efficiency test
Start the fuel cell power system; disconnect the auxiliary energy storage module;
run the fuel cell power system for 30 minutes at the rated power W rating. Divide
the cumulative net power generation energy during this period by the energy as
corresponding to the cumulative hydrogen consumption Q consumption (use a low
enthalpy value of 242 kJ/mol). Use the formula (1) to calculate the electric
efficiency η generation of the fuel cell power system (1 kW·h = 3600 kJ).
η generation = [0.5 x W rated / (242 x Q consumption/3600)]×100% ……………………(1)
Where:
η generation - Electric efficiency;
W Rated - Rated power, in kilowatts (kW);
Q consumption - The cumulative hydrogen consumption, in moles (mol).
6.8 Test of startup/shutdown mode
The test of the startup/shutdown method is carried out according to the following
methods:
- When testing the manual mode, manually starts up or shuts down the fuel
cell power system, to check whether the system starts up or shuts down
normally;
- When testing the remote-control mode, start or shut down the fuel cell
power system remotely, to check whether the system starts up or shuts
down normally;
- When testing the automatic mode, start or shut down the fuel cell power
system regularly; check whether the system starts up or shuts down
normally. The software tips attached to the product can be used as one of
the criteria.
6.9 Test of shutdown time
When the fuel cell power system is running at rated power, it sends a shutdown
command to the fuel cell power system manually, remotely or automatically, to
measure the time from when the shutdown command is issued to the time when
all components of the fuel cell power system stop working.
6.10 Test of continuous operation time
Continuously operate the fuel cell power system at rated power, to measure the
length of time that the output voltage of the fuel cell power system does not
exceed the output voltage range indicated by the manufacturer.
6.11 Noise test
The fuel cell power system is operated at the rated output power. Use a noise
meter to measure the noise at a distance of 1 m from the center point of the
front, back, left, right, upper and lower measurement planes of the fuel cell
power system. Use the method specified in 4.4 of GB/T 4980-2003 to determine
the measuring plane in each direction. The difference between the readings of
the noise meter when there is noise to be measured and when there is no noise
to be measured shall not be less than 10 dB; otherwise, use Table 2 for
adjustment.
Table 2 -- Reading compensation affected by background noise
The difference in readings between noise to be measured and no noise to
be measured/dB 3 4 5 6 7 8 9
Compensation value/dB -3 -2 -1
6.12 Vibration resistance test
The fuel cell power system is rigidly connected to the vibrating bench. The fuel
cell power system is operated at the rated output power. In the three directions
of X, Y, Z, perform the test based on the vibration power spectrum shape and
the acceleration spectrum’s root mean square value ......
 
Source: Above contents are excerpted from the PDF -- translated/reviewed by: www.chinesestandard.net / Wayne Zheng et al.