GB/Z 35733-2017Guidelines for electromagnetic compatibility requirements of equipments constituting and access to smart grid (English PDF)

Foreword

This guiding technical document was drafted in accordance with the rules given in GB/T 1.1-2009.

This guiding technical document was proposed by and is under the jurisdiction of the National Technical Committee on Radio Interference of Standardization Administration of China (SAC/TC 79).

The organization responsible for drafting this guiding technical document is the Shanghai Electrical Apparatus Research Institute. The participating drafting organizations are the China Electric Power Research Institute, Wekey Testing Technology Co., Ltd. and the China Household Electric Appliance Research Institute.

The main drafters of this guiding technical document are Chen Hao, Ye Qiongyu, Zhao Mingmin, Zeng Bo, Zhang Yanyan, Zheng Junqi, Zhang Jiangong and Xing Lin.

1 Scope

This guiding technical document specifies the electromagnetic compatibility (EMC) requirements and the test conditions for the equipment that makes up and connects to the smart grid, specifically for smart grid customer-domain equipment and for the secondary equipment of power plants and substations.

This guiding technical document applies to the equipment that makes up and connects to the smart grid (the dashed box of Figure 1), mainly smart grid customer-domain equipment and the secondary equipment of power plants and substations. The smart grid customer domain includes but is not limited to: equipment used at the smart grid customer end; equipment of smart grid measuring, protection or control modules (for example smart meters or auxiliary equipment installed at the customer end); and area generation or energy storage equipment at the customer end (for example a smart grid power conversion device).

Figure 1 gives the conceptual model of the smart grid domains: markets, operators and service providers above, and generation, transmission, distribution and the customer end within the dashed box, linked by secure communication and by electric power transmission. This guideline is concerned with the part inside the dashed line.

This guiding technical document does not apply to the primary equipment of power plants and substations or to equipment with a rated voltage higher than 1 000 V.

2 Normative references

The following documents are indispensable for the application of this document. For dated references, only the edition cited applies. For undated references, the latest edition (including all amendments) applies.

GB 4343.1, Electromagnetic compatibility requirements for household appliances, electric tools and similar apparatus - Part 1: Emission; GB/T 4343.2-2009, Part 2: Immunity; GB/T 4365, Electrotechnical terminology - Electromagnetic compatibility; GB 4824, Industrial, scientific and medical (ISM) radio-frequency equipment - Disturbance characteristics - Limits and methods of measurement.

GB/T 6113.104-2016, Specification for radio disturbance and immunity measuring apparatus and methods - Part 1-4: Antennas and test sites for radiated disturbance measurements; GB/T 6113.201, Part 2-1: Conducted disturbance measurements; GB/T 6113.203-2016, Part 2-3: Radiated disturbance measurements; GB/T 6113.402, Part 4-2: Uncertainty of measuring equipment and facilities.

GB/T 9254-2008, Information technology equipment - Radio disturbance limits and methods of measurement; GB/T 9383-2008, Sound and television broadcast receivers and associated equipment - Immunity - Limits and methods of measurement; GB/T 13837-2012, Sound and television broadcast receivers and associated equipment - Radio disturbance characteristics - Limits and methods of measurement; GB/T 17618-2015, Information technology equipment - Immunity - Limits and methods of measurement.

GB 17625.1-2012, Electromagnetic compatibility - Limits - Limits for harmonic current emissions (equipment input current not more than 16 A per phase); GB/T 17625.2-2007, Limitation of voltage changes, voltage fluctuations and flicker; GB/T 17625.7-2013, for equipment with rated current not more than 75 A and conditional connection; GB/T 17625.8-2015, harmonic current limits for equipment with input current greater than 16 A and not more than 75 A per phase.

GB/T 17626.2 to GB/T 17626.29, Electromagnetic compatibility - Testing and measurement techniques, covering electrostatic discharge, radiated radio-frequency electromagnetic field, electrical fast transient/burst, surge, conducted disturbances induced by radio-frequency fields, power-frequency magnetic field, pulse magnetic field, damped oscillatory magnetic field, voltage dips and short interruptions, ring wave, low-frequency immunity to harmonics and interharmonics on the AC power port, voltage fluctuation, 0 Hz to 150 kHz common-mode conducted disturbance, ripple on the DC input power port, and voltage dips and short interruptions on the DC input power port.

GB/T 17743, Limits and methods of measurement of radio disturbance characteristics of electrical lighting and similar equipment; GB/T 17799.1-1999 and GB/T 17799.2-2003, Electromagnetic compatibility - Generic standards - Immunity for residential, commercial and light-industrial environments and for industrial environments; GB 17799.3 and GB 17799.4, the corresponding emission standards; GB/T 18595-2014, General lighting equipment - EMC immunity requirements; CISPR 11:2015; CISPR 22; CISPR 24.

3 Terms and definitions and abbreviations

3.1 Terms and definitions. The terms and definitions given in GB/T 4365 and the following apply to this document.

3.1.1 smart grid - an intelligent electric power network that integrates all the customer ends connected to it (including generation, users and those having both functions), so as to provide a sustainable, economic and safe electricity supply effectively.

3.1.2 smart grid customer domain - the terminals of the power system suited to the smart grid (below the distribution transformer), the equipment and systems that carry out the intelligent distribution, storage, use, access and management of electric energy. Note: the smart grid customer domain specifically includes a) smart customer-end distribution products (systems); b) smart terminal electricity-using products (systems); c) distributed energy products (systems); d) energy storage products (systems); e) energy management products (systems).

3.1.3 electromagnetic compatibility (EMC) - the ability of equipment or a system to function normally in its electromagnetic environment without constituting an intolerable electromagnetic disturbance to anything in that environment.

3.1.4 electromagnetic disturbance - any electromagnetic phenomenon that may degrade the performance of a device, equipment or system, or adversely affect living or inert matter. Note: an electromagnetic disturbance may be electromagnetic noise, an unwanted signal or a change in the propagation medium itself. [GB/T 4365-2003, definition 161-01-05]

3.1.5 electromagnetic interference (EMI) - the degradation of the performance of equipment, a transmission channel or a system caused by an electromagnetic disturbance. [GB/T 4365-2003, definition 161-01-06]

3.1.6 port - the physical interface at which electromagnetic energy enters or leaves the EUT. 3.1.7 enclosure port - the physical boundary of the equipment, through which electromagnetic fields may radiate outwards or enter. 3.1.8 AC/DC mains power port - the port used to connect to the AC or DC power network. Note 1: equipment with a DC port is supplied through an AC/DC converter in the AC grid. Note 2: the DC supply port may be used for communication, including a wired network such as an Ethernet port.

3.1.9 signal/control port - a port on the equipment to which conductors or cables carrying data information are connected. Note: for example a data bus, a communication network and a control network. 3.1.10 antenna port - the port to which an antenna is connected for the internal transmission and/or reception of radiated radio-frequency energy. Note: the antenna port differs from the broadcast receiver tuner port. 3.1.11 wired network port - a port for the interconnection of widely distributed system voice, data and signalling, connected directly to a single-user or multi-user communication network (such as cable television, telephone, ISDN, xDSL, LAN and similar networks).

3.1.12 broadcast receiver tuner port - a port used to receive the modulated RF signals carrying terrestrial, satellite and/or audio and/or video broadcast cable transmission and similar services. Note: this port may be connected to an antenna, a cable distribution system, a VCR or similar equipment. 3.1.13 RF modulator output port - a port connected to the modulation port of a broadcast receiver, transmitting the signal to the broadcast receiver. 3.1.14 optical fibre port - a port connected to the equipment through an optical fibre. 3.1.15 analogue/digital data port - a signal/control port (3.1.9), antenna port (3.1.10), wired network port (3.1.11), broadcast receiver tuner port (3.1.12) or optical fibre port (3.1.14) with a metal shield and/or metal elastic strain relief. 3.1.16 power line communication port (PLC port) - a port connected to the low-voltage AC power network, used for data transmission and communication and able to supply electric energy to the equipment.

3.1.17 power plants and substations primary system - the equipment of the main systems of generation, transmission and distribution. Note: such as generators, power transformers and the reactors, circuit breakers, isolating switches, arresters and fuses in the main power circuit. 3.1.18 power plants and substations secondary system - the equipment that carries out the control, monitoring and protection of the primary equipment. Note: such as relay protection devices, signal transmission devices and measuring instruments. 3.1.19 merging unit (MU) - the device that merges and synchronizes the electrical quantities transmitted from the secondary circuits of the instrument transformers and forwards the processed digital signals in a particular format for use by the bay-level equipment.

3.2 Abbreviations. The following abbreviations apply to this document. EUT: Equipment Under Test. IP: Internet Protocol. RF: Radio Frequency. WiFi: Wireless Fidelity. WiMAX: Worldwide Interoperability for Microwave Access.

4 Overview of the electromagnetic environment of the smart grid

The design of all equipment making up and connecting to the smart grid needs to consider EMC questions. First, the equipment must be prevented from interfering with radio services and with the public grid; equally, the equipment must be guaranteed to run normally in the electromagnetic environment in which it is installed. In addition, this equipment shall not produce conducted or radiated interference to nearby equipment, including equipment connected nearby on the smart grid.

The following ports may be used for input or output; in many cases the ports of equipment connected to the smart grid need to satisfy both output and input functions. Figure 2 gives the ports that smart grid equipment in the customer domain may have: optical fibre port, RF modulator output port, broadcast receiver tuner port, antenna and antenna port on one side, and AC/DC mains power port, power line communication port (power plus communication), wired network port and signal/control port on the other, all around the enclosure.

The characteristic of the smart grid is the exchange of data of the grid and the sending of electric energy out of or into the public grid. The following technical conditions need to be considered in the present implementation and the future development of the smart grid: power line communication (PLC) with a communication frequency below 150 kHz; PLC with a communication frequency above 150 kHz and below 500 kHz; PLC with a communication frequency above 1 700 kHz; public mobile communication such as 2G/3G/4G/5G; wireless communication such as WiMAX/WiFi/Zigbee/Bluetooth/trunked communication; mesh RF; and wired IP.

This guiding technical document puts forward requirements for the equipment making up and connecting to the smart grid on the basis of the above smart grid characteristics; the general requirements for electromagnetic compatibility testing are given in Annex A and the specific electromagnetic compatibility requirements are set out in Clause 5 and Clause 6. Two electromagnetic environments are considered: environment A, relating to places or installations with a low-voltage non-public grid or an industrial grid; and environment B, relating to a low-voltage public grid, such as domestic, commercial and light-industrial places or installations. The manufacturer shall specify in the information provided to the user the application environment of the equipment connected to the smart grid (that is, the application category of the equipment). If the manufacturer has specified an optional electromagnetic shielding enclosure (such as a cabinet) or another protective component (such as a filter), these shall be part of the EUT.

5 Secondary equipment of power plants and substations

5.1 Electromagnetic disturbance requirements. The electromagnetic compatibility (EMC) requirements for the secondary equipment of power plants and substations shall follow the EMC requirements for environment A equipment in GB 4824.

5.2 Electromagnetic immunity requirements. 5.2.1 Overview. The secondary equipment of power plants and substations shall be subjected to immunity tests according to the requirements of Table 1 to Table 5. Equipment installed in a protected area and not directly connected to other areas need not meet the immunity requirements of 5.2, but shall meet the relevant generic or product standard.

5.2.2 Other immunity requirements. For the immunity requirements of the secondary equipment of power plants and substations, while conforming to 5.2.1, the following conditions shall also be considered: a) for the requirements on the merging unit, whose function is to collect and synchronize the status data of the primary equipment and pass it to the relay protection device for analysis and processing, its position is near the primary equipment and its importance and performance requirements shall be the same as those of local protection and remote protection devices; b) online monitoring equipment: electrostatic discharge requirement level 4; c) smart sensors close to the primary equipment shall be assessed according to 5.2; d) for unattended substations the performance criteria shall be stricter, and shall meet the requirements of performance level B of the generic standards; e) for optical fibre ports, only radiated immunity and electrostatic discharge immunity are measured; f) the shielding requirements for online monitoring equipment and smart component cabinets are under consideration.

6 Customer-domain equipment

6.1 Electromagnetic disturbance requirements. 6.1.1 Overview. Table 6 gives the reference standards for the EMC electromagnetic disturbance tests of customer-domain equipment; the reference standard and the measurement requirements shall be chosen according to the specific category of the product. In the ordinary case a product-class standard should be chosen first, and where there is no suitable product-class standard a generic standard (GB 17799.3, GB 17799.4) may be chosen. Table 6 pairs the product category with the reference standard and the test items: industrial, scientific and medical - GB 4824; sound and television broadcast - GB/T 13837-2012; household appliances and electric tools - GB 4343.1; lighting equipment - GB/T 17743; information technology - CISPR 22, all tested for conducted disturbance and radiated disturbance; other products belonging to environment B - GB 17799.3, and other products belonging to environment A - GB 17799.4, tested for conducted disturbance, radiated disturbance, harmonic current and voltage fluctuation.

Besides meeting the requirements of Table 6, the electromagnetic disturbance requirements for smart grid customer-domain equipment shall also, on the basis of the characteristics of the smart grid electromagnetic environment and the requirements of standard adaptability, be tested for the applicable electromagnetic disturbance items of 6.1.2 to 6.1.7.

6.1.2 Harmonic emission. Products with a rated current below 16 A are tested for harmonic current according to GB 17625.1-2012 and products with a rated current of 16 A to 75 A according to GB/T 17625.8-2015, under the following conditions: a) test port: the AC power input connected to the public grid; b) limits: the corresponding limits of GB 17625.1-2012 or GB/T 17625.8-2015.

6.1.3 Voltage fluctuation. Products with a rated current below 16 A are tested for voltage fluctuation according to GB/T 17625.2-2007 and products with a rated current of 16 A to 75 A according to GB/T 17625.7-2013. 6.1.4 to 6.1.7 give the corresponding test conditions and limits for conducted disturbance from 9 kHz to 150 kHz, conducted disturbance from 150 kHz to 30 MHz, radiated disturbance from 9 kHz to 30 MHz and radiated emission from 1 GHz to 6 GHz.

6.2 Electromagnetic immunity requirements, covering the overview (6.2.1), low-frequency conducted immunity from 15 Hz to 150 kHz (6.2.2) and the supplementary description of the performance criteria (6.2.3). 6.2.3 Supplementary description of the performance criteria. The manufacturer shall provide a functional description of the performance criteria defined during the EMC test or in the test results (which shall include in detail the normal operation, data display, data acquisition, communication state and the like of the equipment connected to the smart grid), and shall record the test results in the test report according to the different criteria requirements of the reference standards. The following functions are considered to be particularly relevant to the equipment and the system: protection and remote protection; online processing and regulation; metering; command and control; supervisory control; the man-machine interface; alarm; data transmission and communication; data acquisition and storage; measurement; offline processing; monitoring; and self-diagnosis.

7 Test conditions

When emission measurements are made within a particular frequency range, the equipment under test (EUT) shall be measured in the operating state that produces the maximum disturbance, for example on the basis of limited pre-measurement and normal use conditions. Under the typical use and actual installation conditions of connection to the smart grid, the configuration of the EUT is varied so as to obtain the maximum disturbance.

If the EUT is part of a system, or is connected to auxiliary equipment, the EUT shall be configured with at least representative auxiliary equipment when measured. If the manufacturer requires an external filtering or shielding device, or measures are specified in the user manual, then the measurement of this guiding technical document shall be carried out with the specified device and measures added.

The configuration and operating state of the equipment under test during the test shall be correctly recorded in the test report. If the equipment has many similar ports, or some ports have many similar connections, then a sufficient number of ports and connections shall be selected to simulate the actual operating state, so as to guarantee that all port types are covered; the number of ports selected is agreed between the laboratory and the user. Unless otherwise specified in another standard, the measurement shall be carried out under the temperature, humidity and atmospheric pressure operating conditions specified for the equipment.

8 Measurement uncertainty

The uncertainty of the results of electromagnetic disturbance measurement shall be evaluated according to the relevant provisions of GB/T 6113.402.

For a given measurement method, if the actual U(lab) value is greater than U(cispr), then the value of U(lab) is required to be recorded in the report.

9 Test results and test report

The test report shall contain all the information necessary to reproduce the test. In particular the following information shall be recorded: the items specified in the test plan of this guiding technical document; the description of the equipment under test, its dimensions, and the identification of the equipment under test and of any associated equipment, for example the trade name, the product model and the serial number; and the test plan.

Annex A (informative) General requirements for the EMC testing of equipment making up and connecting to the smart grid

Annex A gives the general requirements for the EMC testing of equipment making up and connecting to the smart grid, including the test set-up and arrangement, the configuration and operating conditions of the equipment under test, the treatment of the various ports, the measuring apparatus and test sites, and the performance criteria applied to the immunity tests.