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According to the requirements of Notice on Printing Development and Revision Plan for Engineering Construction Standards and Codes in 2014 (JIANBIAO [2013] No. 169) issued by Ministry of Housing and Urban-Rural Development of the People's Republic of China, this code is revised by the drafting group through extensive investigation and study, careful summarization of practical experience since the implementation of the previous code, widely solicitation for opinions of relevant design, management and operation organizations.
This code consists of 9 chapters and 3 annexes. Main technical contents of this code are General Provisions, Terms and Symbols, Electrical Measuring Device, Energy Metering, Measuring of the Computerized Monitoring and Control System, Electrical Measuring Transducers, Current and Voltage Transformer for Metering, Secondary Wring for Metering, Measuring Meter Device Installation Conditions.
Main technical contents revised in this code are as follows:
1 The application scope of this code is expanded; items such as grid-connected wind power generation and photovoltaic power generation are added.
2 Corresponding terms and symbols are supplemented.
3 Provisions on the electrical measuring of grid-connected wind power generation and photovoltaic power generation projects are added.
4 Requirements for measuring accuracy of smart meter, integrated protection and measuring and control devices are added.
5 Electrical measuring and energy metering chart is supplemented and adjusted.
6 General requirements for the application of electronic current and voltage transformer are added.
7 Provisions on adaptability of relevant electrical measuring are supplemented in allusion to the digitalization requirements of power plant and substation.
8 Electrical measuring provisions on ultra-high-voltage direct current (UHVDC) convertor station are added.
The Ministry of Housing and Urban-Rural Development is in charge of the administration of this code, China Electricity Council is responsible for the routine management, and Southwest Electric Power Design Institute of China Power Engineering Consulting Group is responsible for the explanation of specific technical contents. All relevant organizations are kindly requested to sum up experiences and accumulate information according to engineering practices during the process of implementing this code. The relevant opinions and advice, whenever necessary, can be fed back to Southwest Electric Power Design Institute of China Power Engineering Consulting Group (Address: No. 18, Dongfeng Road., Chengdu, Sichuan, 610021) for future reference in revision.
Contents
Foreword i
1 General Provisions 1
2 Terms and Symbols 1
2.1 Terms 1
2.2 Symbols 3
3 Electrical Measuring Device 4
3.1 General Requirements 4
3.2 Current Measuring 6
3.3 Voltage Measuring and Insulation Monitoring 8
3.4 Power Measuring 9
3.5 Frequency Measuring 11
3.6 Public Supply Network Harmonics Monitoring 11
3.7 Power Plants, Substation Public Electrical Measuring 12
3.8 Static Compensator and Series Compensator Measuring 13
3.9 DC Converter Station Electrical Measuring 15
4 Energy Metering 17
4.1 General Requirement 17
4.2 Active, Reactive Power Energy Metering 18
5 Measuring of the Computerized Monitoring and Control System 19
5.1 General Requirements 20
5.2 Data Acquisition of Computerized Monitoring and Control System 20
5.3 Computerized Monitoring and Control System with General Electrical Measuring Meter 20
6 Electrical Measuring Transducers 21
7 Current and Voltage Transformer for Metering 22
7.1 Current Transformer 22
7.2 Voltage Transformer 23
8 Secondary Wiring for Metering 24
8.1 AC Current Loop 24
8.2 AC Voltage Loop 25
8.3 Secondary Measurement Loop 26
9 Measuring Meter Device Installation Conditions 27
Annex A Calculation of Measuring Meter Full-scale Value 29
Annex B Calculation of Electrical Measuring Transducers Calibration Value 31
Annex C Chart of Electrical Measuring and Energy Metering 33
Explanation of Wording in This Code 47
List of Quoted Standards 48
Code for Design of Electrical Measuring Device of Power System
1 General Provisions
1.0.1 This code is prepared with a view to specifying the design of electrical measuring device of power system and making the device accurate, reliable, technology-advanced, convenient in monitoring and operation management, economical and reasonable and unified in design.
1.0.2 This code is applicable to the design of electrical measuring device of power system for newly-built or extended turbine generator and gas turbine power plant with unit capacity of Grade 1,000MW or below, hydraulic power plant with unit capacity of 200kW or above [including pumped storage power plant, conventional island part of nuclear power station, transformer (distribution) substation with AC rated voltage of 10kV or above, including series compensation station, DC converter station with DC rated voltage of ±800kV or below] as well as grid-connected wind power generation and PV power stations.
1.0.3 In addition to the requirements stipulated in this code, the design of electrical measuring device of power system shall also comply with those in the relevant current standards of the nation.
2 Terms and Symbols
2.1 Terms
2.1.1 electrical measuring
measuring of real-time electrical parameters by electric ways
2.1.2 energy metering
metering of energy parameters
2.1.3 general electrical measuring meter
the meter for frequently measuring, selectively measuring and recording electrical operation parameters of power system circuit
2.1.4 pointer-type meter
the meter which indicates the measured value based on the relationship between pointer and scale
2.1.5 digital-type meter
the meter which directly displays the measured value on the display digitally
2.1.6 multifunction power meter
a kind of multifunctional smart meter capable of programming measurement, displaying, digital communication and electric energy pulse transmitting output, etc.
2.1.7 energy meter
the instrument for metering active (reactive) energy data
2.1.8 induction energy meter
the energy meter working by the rotation of electric induction measuring element disc
2.1.9 electronic energy meter
the energy meter sampling voltage and current in real time, processing sample voltage and current signals by special energy meter integrated loop and displaying via register or digital indicator
2.1.10 multifunction energy meter
the energy meter which consists of measuring unit and data processing unit for metering demand by time and direction [including one-way or two-way active (reactive) energy], and can display, store and output data
2.1.11 voltage loss time counter
the special instrument which accumulates and displays loss time of the voltage loop of an energy meter
2.1.12 energy tariff point
the metering point for energy settlement between power generation enterprises and power grid enterprises
2.1.13 electrical measuring transducers
the device which converts the measured value to DC current, DC voltage or digital signal
2.1.14 calibration value for transducers
the value obtained by changing the nominal value of transducer through adjustment according to the user's demand
2.1.15 measuring instrument accuracy class
the class of the measuring instrument and (or) accessories in accordance with specific metering requirements to guarantee the permissible error and variation within the specified limit
2.1.16 measuring instrument intrinsic error
the error of the measuring instrument and (or) accessories under the reference condition
2.1.17 total measuring error
the resultant error caused by the measuring meter, transformer and their measuring secondary loop
2.1.18 energy tariff equipment
the device which meters energy parameters at energy tariff points, including various energy meters, voltage and current transformer for measuring and their secondary loop, and energy metering cabinet (box), etc.
2.1.19 energy tariff meter
the energy meter equipped for energy tariff equipment
2.2 Symbols
R——the resistance;
X——the reactance;
Z——the impedance;
I——the current;
U——the voltage;
P——the active power;
Q——the reactive power;
S——the apparent power;
W——the active energy;
WQ——the reactive energy;
PF——the power factor;
f——the frequency.
3 Electrical Measuring Device
3.1 General Requirements
3.1.1 Electrical measuring device shall be capable of reflecting the electrical parameters and insulation state of the operation conditions of power system.
3.1.2 Direct meter, primary meter or secondary meter may be adopted as electrical measuring devices. Electrical measuring device configured for the measurement by direct meter shall meet the requirements of dynamic thermal stability of primary loop.
3.1.3 Accuracy of electrical measuring device shall not be inferior to those specified in Table 3.1.3.
Table 3.1.3 Minimum Requirements for Accuracy of Electrical Measuring Device
Type of electrical measuring device Accuracy
Computerized monitoring and control system AC sampling Class 0.5
Frequency measuring error ≤ 0.01Hz
DC sampling Analog-digital conversion error ≤0.2%
General electrical measuring meter Pointer-type AC meter Class 1.5
Pointer-type DC meter Class 1.0 (secondary measuring by transducer)
Class 1.5
Digital-type meter Class 0.5
Record-type meter It shall meet the requirements for accuracy of measuring objects.
Measuring part in integrated protection measuring and control device Class 0.5
3.1.4 The integrated accuracy of AC loop indicator shall not be lower than Class 2.5 and that of DC loop indicator shall not be lower than Class 1.5; the accuracy of secondary measuring meter connected to electrical measuring transducer shall not be lower than Class 1.0. The accuracy of current and voltage transformers as well as accessories of electrical measuring device shall not be lower than those specified in Table 3.1.4.
Table 3.1.4 Requirements for Accuracy (Class) of Current and Voltage Transformers as well as Accessories and Fittings of Electrical Measuring Device
Accuracy of electrical measuring device Accuracy of accessories and fittings
Current and voltage transformers Transducer Shunt Intermediate transformer
0.5 0.5 0.5 0.5 0.2
1.0 0.5 0.5 0.5 0.2
1.5 1.0 0.5 0.5 0.2
2.5 1.0 0.5 0.5 0.5
3.1.5 The measuring range of pointer-type measuring meter should keep the rated value of electrical equipment indicating at 2/3 of the meter scale. Overload meter should be adopted for the power equipment and loop under overload operation; for the motor under heavy load startup and the power equipment and loop that may have short time, ammeter with overload marking scale should be adopted.
3.1.6 Selective measuring mode may be adopted for electrical measuring of multiple same type of power equipment and loops.
3.1.7 For secondary measuring meter of transducer, its full-scale value shall be matched with the calibration value of transducer, and may be calculated according to Annex A and Annex B.
3.1.8 Ammeter and wattmeter with two-way scale shall be adopted for DC loop with two-way current and AC loop with two-way power. Polar meter shall be adopted for polar DC current and voltage loop.
3.1.9 The transducer can be shared by secondary measuring meter and computerized monitoring and control system when inputting by transducer is adopted for the remote telemeter system and computerized monitoring and control system installed for power plant and substation (distribution station).
3.1.10 The upper limit value of excitation loop instrument shall not be lower than 1.3 times of the rated condition. The total error of the instrument shall not exceed 1.5%. The generator exciting winding ammeter should be accessed via the transducer installed nearby.
Foreword i
1 General Provisions
2 Terms and Symbols
2.1 Terms
2.2 Symbols
3 Electrical Measuring Device
3.1 General Requirements
3.2 Current Measuring
3.3 Voltage Measuring and Insulation Monitoring
3.4 Power Measuring
3.5 Frequency Measuring
3.6 Public Supply Network Harmonics Monitoring
3.7 Power Plants, Substation Public Electrical Measuring
3.8 Static Compensator and Series Compensator Measuring
3.9 DC Converter Station Electrical Measuring
4 Energy Metering
4.1 General Requirement
4.2 Active, Reactive Power Energy Metering
5 Measuring of the Computerized Monitoring and Control System
5.1 General Requirements
5.2 Data Acquisition of Computerized Monitoring and Control System
5.3 Computerized Monitoring and Control System with General Electrical Measuring Meter
6 Electrical Measuring Transducers
7 Current and Voltage Transformer for Metering
7.1 Current Transformer
7.2 Voltage Transformer
8 Secondary Wiring for Metering
8.1 AC Current Loop
8.2 AC Voltage Loop
8.3 Secondary Measurement Loop
9 Measuring Meter Device Installation Conditions
Annex A Calculation of Measuring Meter Full-scale Value
Annex B Calculation of Electrical Measuring Transducers Calibration Value
Annex C Chart of Electrical Measuring and Energy Metering
Explanation of Wording in This Code
List of Quoted Standards
