Standards Development

Scope

This proposal is applicable to photovoltaic (PV) power plants connected to the power grid. It provides a
uniform method that will ensure the testing of the electrical characteristics of PV power plants. The electrical characteristics include: power quality, active power control, reactive power control, voltage control, frequency control, etc.
The tests shall refer to the point of connection (POC) of the PV power plant. The procedure describes
standardized methods which will allow the TSO/DSOs to analyze the grid compliance regarding the above electrical characteristics.
The proposal includes the following aspects:
(1) definition and specification of the quantities to be determined for the electrical characteristics of PV power plants;
(2) test procedures for quantifying the electrical characteristics, including the test procedures for the commissioning of PV power plants;
(3) functionality test procedure of PV Power Plant Controller (PPC) based on Hardware -in-the-Loop (HIL) simulation.

The test procedures shall be valid for PV power plants including the PPC and other connected equipment essential for the operation of the PV power plant. These procedures shall be valid for PV power plant of any size connected to the POC at medium voltage (MV), high voltage (HV) or extra high voltage (EHV) level. The test procedures are designed to be as non-site-specific as possible.

Purpose

As an important form of renewable energy, PV power generation is showing explosive growth worldwide. By the end of 2023, the cumulative installed capacity of solar PV in the world has reached 1.42TW. Based on the characteristics of PV power generation, a detailed analysis of the grid- connected interface is required, to analyze the grid support requirements in the POC to fulfill the grid code or the grid connection agreements.
Grid codes in many countries require PV power plants to participate in the voltage and frequency regulation of the power system, which puts forward specific requirements for the range, accuracy, and response time of active and reactive power control of PV power plants. Consequently, the grid compliance tests for PV power plants is especially critical.
The electrical characteristics of PV power plants is affected by several factors, primarily including:
performance variability due to parallel configuration of a large number of PV inverters; multiple time delays in power control which can vary significantly between individual power plants; impact on output power affected by meteorological conditions, capacity ratios, and the type of PV mounts, etc.
An on-site test can truly reflect the real grid-connected performance of PV power plants, as opposed to
evaluations based solely on the performance of individual PV power generation units. Therefore, it is
essential to develop precise methods for testing the grid-connected performance of PV power plants directly on-site.
This proposal introduces a standardized on-site testing method designed specifically for entire PV power plants. It can not only obtain the closest result to the real situation by using this method, but also provide unified criteria for grid-connected performance test of different power plants.
This document shall help to coordinate the various national testing standards, or provide a method to those countries who have no testing standard. Furthermore, the test data generated from this method can serve as input for conducting grid code compliance assessments of PV power plants in accordance with IEC TS 63102:2021.
This proposal has already had multiple rounds of communication with the IEC TC 82 (Solar photovoltaic energy systems) during the preparation process, and will continue to maintain close communication and cooperation in the subsequent development process to avoid unnecessary duplication.