PD IEC/TS 62786:2017 pdf free.Distributed energy resources connection with the grid.
This technical specification 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.
NOTE Mobile electrical energy storage devices (e.g. electrical vehicles) are under consideration for future editions.
The requirements of this document can be superseded by laws and regulations where applicable.
2 Normative references
The following documents are referred to in the text in such a way that some or all of their content constitutes requirements 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.
IEC 61000 (all parts), Electromagnetic compatibility (EMC)
IEC TS 62749, Assessment of power quality — Characteristics of electricity supplied by public networks
3 Terms and definitions
For the purposes of this document, the following terms and definitions apply.
4.1 General When connecting a DER to the distribution network, consideration should be given to whether there are other power resources connected or to be connected in the same electrical proximity. The combined effect of DERs should be considered when selecting an appropriate POC for the DER concerned.
4.2 Connection scheme
The generating plant shall be in compliance with the requirements of the DSO. Different requirements may be subject to agreement between the operator of the DERs and the DSO depending on the electric power system needs.
4.3 Choice of switchgear
4.3.1 General
Switches shall be chosen based on the characteristics of the electric power system in which they are intended to be installed. For this purpose, the short circuit current at the installation point shall be assessed taking into account the contribution of the generating plant.
Depending on local system requirements, generating plant should be equipped at the connection point with isolating devices and visible signs that are easily operated and lockable, The method of isolating the generating plant connected to a MV network shall be accessible
to the DSO at all times, unless the DSO requires or permits using an alternative method.
NOTE In some countries, accessibility is also required for the DERs connected to a LV nelworl.
4.3.2 Interface switch
Interface switches shall have a breaking and making capacity corresponding to the rated current of the generating plant and corresponding to the short circuit contribution of the generating plant.
The short-time withstand current of the switching devices shall be coordinated with maximum short circuit current at the POC.
In case of loss of auxiliary power supply to the switchgear, the interface switch shall disconnect immediately. An uninterruptible power supply may be required by the DSO.
The interface switch may coincide either with the main switch or with the generating unit switch. In case of a combination, the single switch should be compliant to the requirements of the two separate switches. As a consequence. at least two switches in series should be present between any generating unit and the POC. One of the two switches may include electronic switch (gate blocking) in case of converter connection.PD IEC/TS 62786 pdf download.