Technical rule for distributed resources connected to power grid
1 Scope
This standard specifies the general principles and technical requirements to be followed in the operation of newly built and expanded distributed sources connected to power grid. The reconstruction of distributed resources and distributed self-contained resources can refer to this standard.
This standard is applicable to distributed resources connected to power grid with voltage levels of 35kV and below in the form of synchronous generators, asynchronous generators and converters in the operating areas of the State Grid Corporation of China.
2 Normative references
The following referenced documents are indispensable for the application of this document. For dated references, only the edition cited applies. For undated references, the latest edition of the referenced document (including any amendments) applies.
GB 2894 Safety signs and guideline for the use
GB 14050 Types and safety technical requirements of system earthing
GB/T 12325 Power quality—Deviation of supply voltage
GB/T 12326 Power quality—Voltage fluctuation and flicker
GB/T 14285 Technical code for relaying protection and security automatic equipment
GB/T 14549 Quality of electric energy supply—Harmonics in public supply network
GB/T 15543 Power quality—Three-phase voltage unbalance
GB/T 19862 General requirements for monitoring equipment of power quality
GB/T 24337 Power quality—Interharmonics in public supply network
DL/T 448 Technical administrative code of electric energy metering
DL/T 584 Setting guide for 3kV~110kV power system protection equipment
DL/T 621 Grounding for AC electrical installations
DL/T 634.5101 Telecontrol equipment and systems—Part 5: Transmission protocols—Section 101: Companion standard for basic telecontrol tasks
DL/T 634.5104 Telecontrol equipment and systems—Part 5-104: Transmission protocols—Network access for IEC 60870-5-101 using standard transport profiles
Regulations for safety protection of electric power monitoring system Decree [2014] No.14 of the National Development and Reform Commission
3 Terms and definitions
For the purposes of this document, the following terms and definitions apply.
3.1
point of common coupling
connecting point of more than one user in a power system
3.2
point of interconnection
the bus or node on the high-voltage side of step-up substation for distributed resources with step-up substation bus of output for distributed resources without step-up substation See Annex A for the definition of the point of interconnection
3.3
converter
an electrical device for converting electrical power into one or more forms of electrical power suitable for use by a grid or a user, including rectifier, inverter, AC converter and DC converter
3.4
synchronous-machine-type power supply
a power supply directly connected to the power grid through a synchronous generator
3.5
asynchronous-machine-type power supply
a power supply directly connected to the power grid through an asynchronous generator
3.6
converter-type power supply
a power supply connected in whole or in part to the power grid through a converter
3.7
islanding
the state in which part of a power grid containing load and power supply continues to operate in isolated manner after being separated from the main grid, including unintentional islanding and intentional islanding
unintentional islanding
islanding occurring in an unintentional and uncontrolled manner
intentional islanding
islanding occurring in an intentional manner according to the preset control strategy
3.8
anti-islanding
prevention from unintentional islanding
Foreword i
1 Scope
2 Normative references
3 Terms and definitions
4 Basic requirements
5 Power quality
5.1 General requirements
5.2 Harmonics
5.3 Voltage deviation
5.4 Voltage fluctuation and flicker
5.5 Voltage unbalance
5.6 DC component
5.7 Electromagnetic compatibility
6 Start/Stop
6.1 General requirements
6.2 Startup
6.3 Switching off
6.4 Restoration of grid connection
7 Power control and voltage regulation
7.1 Active power control
7.2 Voltage/reactive power regulation
8 Operation adaptability
8.1 General requirements
8.2 Low-voltage ride-through
8.3 Frequency adaptability
9 Safety
9.1 General requirements
9.2 Lightning protection and grounding
9.3 Safety marking
10 Relay protection and automatic safety devices
10.1 General requirements
10.2 Voltage and frequency protection
10.3 Line protection
10.4 Anti-islanding protection
10.5 Automatic reclosing
11 Communications and information
11.1 Basic requirements
11.2 Normal operation information
12 Electric energy metering
13 Grid-connection test
13.1 Test requirements
13.2 Test items
Annex A (Informative) Supplementary explanation on point of interconnection
