JWG 10 - TC 8/JWG 10

IEC TR 62786-102:2025 provides principles and technical needs for the interconnection of the compressed air energy storage (CAES) system to the distribution network. It is suitable for the planning, design, operation and testing of CAES system interconnection to distribution networks. It includes the additional needs for the CAES system, such as connection scheme, grid-connected process and needs, response characteristics of active power to frequency, response characteristics of active power to current, response characteristics of active power to injecting mass flow, response characteristics of active power to pressure, selection of the point of connection (POC), electromagnetic compatibility (EMC) and power quality, communication and automation, monitoring and protection, immunity to disturbances, grid-connected testing needs, etc. This document will report response of active power to frequency, response of active power to current, response of active power to injecting mass flow, response of active power to pressure, response of reactive power to voltage, and grid-connected testing for distributed CAES system, as a supplement for IEC TS 62786-1:2023. This document reports the interface needs for connecting CAES system to distribution network operating at a nominal frequency of 50 Hz or 60 Hz.

IEC TS 62786-3:2023, which is a Technical Specification, provides principles and technical requirements for interconnection of distributed Battery Energy Storage System (BESS) to the distribution network. It applies to the design, operation and testing of BESS interconnected to distribution networks. It includes the additional requirements for BESS, such as connection scheme, choice of switchgear, normal operating range, immunity to disturbance, active power response to frequency deviation, reactive power response to voltage variations and voltage changes, EMC and power quality, interface protection, connection and start to generate electric power, active power management, monitoring, control and communication, and grid-connected tests.
The stationary BESSs considered within the scope of this document include electrical forms such as lead-acid, lithium-ion, liquid flow and sodium-sulfur batteries, interconnected to medium voltage (MV) or low voltage (LV) distribution networks via bidirectional DC to AC power converters. This document will specify active and reactive power response and grid-connected testing for distributed BESS, as a supplement for IEC TS 62786-1:2023.
This document specifies interface requirements for connection of distributed BESS with the distribution network operating at a nominal frequency of 50 Hz or 60 Hz.

IEC TS 62786-1:2023, which is a Technical Specification, provides principles and general technical requirements for distributed energy resources (DER) connected to an electric power network (in the following: the "network"). It applies to the planning, design, operation and connection of DER to networks. It includes general requirements, connection scheme, choice of switchgear, normal operating range, immunity to disturbances, active power response to frequency deviations, reactive power response to voltage changes, EMC and power quality, interface protection, connection and start to generate electrical power, active power management, monitoring, control and communication, and conformance tests.
It is supplemented by additional parts of IEC 62786 series, covering specific aspects.
This document specifies interface and interoperability requirements for connection of DER to a network operating at a nominal frequency of 50 Hz or 60 Hz. These requirements are intended for application at the point of connection (POC) of the DER to the grid. In some situations, the requirements can be the applied at the AC terminals of the generator. Additional parts of IEC 62786 provide more specific requirements.
DER include distributed generation and electrical energy storage in the form of synchronous generators, asynchronous generators, power converters, etc., connected to the medium voltage (MV) or low voltage (LV) network.

IEC TS 62786:2017(E) provides principles and technical requirements for distributed energy resources (DERs) connected to the distribution network. It applies to the planning, design, operation and connection of DERs to distribution networks. It includes general requirements, connection scheme, choice of switchgear, normal operating range, immunity to disturbances, active power response to frequency deviation, reactive power response to voltage variations and voltage changes, EMC and power quality, interface protection, connection and start to generate electrical power, active power management, monitoring, control and communication, and conformance tests.
This document specifies interface requirements for connection of generating plants with the distribution network operating at a nominal frequency of 50 Hz or 60 Hz.
DERs include distributed generation and permanently connected electrical energy storage in the form of synchronous generators, asynchronous generators, converters, etc., connected to the medium voltage (MV) or low voltage (LV) distribution network.

IEC/IEEE/PAS 63547:2011(E) provides interconnection technical specifications and requirements, and test specifications and requirements. It establishes criteria and requirements for interconnection of distributed resources (DR) with electric power systems (EPS).