KR-20260064056-A - PHOTOVOLTAIC APPARATUS AND CONTROL METHOD THEREOF

Abstract

The present invention relates to a photovoltaic power generation device and a control method thereof. The photovoltaic power generation device comprises: a solar cell array that absorbs solar energy and generates electrical energy; a power conversion module that converts direct current power generated from the solar cell array into alternating current power through PQ control and supplies power to a distribution system; a sensor module that detects the voltage of the PCC terminal; and a processor operatively coupled to the power conversion module and the sensor module. The processor is characterized by running an execution program to determine a set peak time period for power generation and performing reactive power control and active power control for the power conversion module based on the voltage of the PCC terminal.

Inventors

• 이정훈
• 김가람
• 박준규
• 전건우

Assignees

• 한국전력공사

Dates

Publication Date

20260507

Application Date

20241031

Claims (5)

1. A solar cell array that absorbs solar energy and generates electrical energy; A power conversion module that converts direct current power generated from the above solar cell array into alternating current power through PQ control and supplies power to the distribution system; A sensor module for detecting the voltage of the PCC; and A processor operatively coupled to the power conversion module and the sensor module; comprising A photovoltaic power generation device characterized by the above processor running an execution program to determine a set peak time period for power generation and performing reactive power control and active power control for the power conversion module based on the voltage of the PCC stage.
2. In paragraph 1, The above processor is, A photovoltaic power generation device characterized by performing reactive power control during the peak power generation time period and performing active power control outside of the peak power generation time period.
3. In paragraph 1, The above power conversion module is, A photovoltaic power generation device comprising an inverter including a PQ controller for controlling active power and reactive power and a current controller as a sub-controller, and characterized by outputting the active power and the reactive power according to the active power control and the reactive power control using Proportional Integral (PI).
4. Step in which the processor receives the PPC terminal voltage; A step in which the above processor determines a set peak time period for power generation; and A control method for a photovoltaic power generation device characterized by including the step of the processor performing reactive power control and active power control through a power conversion module according to the result of determining the peak time period of power generation.
5. In paragraph 1, The step of performing the above reactive power control and active power control is, A control method for a photovoltaic power generation device characterized in that the processor performs reactive power control during the peak power generation time period and performs active power control outside of the peak power generation time period.

Description

Photovoltaic apparatus and control method thereof The present invention relates to a photovoltaic power generation device and a control method thereof, and more specifically, to a photovoltaic power generation device and a control method thereof for stabilizing a power distribution system through PQ (active power/reactive power) control for a photovoltaic power generation device added to a photovoltaic power complex. Today, as many countries implement decarbonization and eco-friendly policies to address the problem of global warming, significant self-help efforts are being made in the energy sector, such as the expanded supply of new and renewable energy and high-efficiency distributed power sources, demand reduction through demand management, and the expansion of the hydrogen industry. In these countries, the deployment of distributed resources—including renewable energy sources and demand resources—is rapidly increasing, and new energy industries are emerging driven by the owners of these expanded distributed resources. As such, the deployment of distributed power sources is continuously expanding under the goal of carbon neutrality, and research for stable supply and efficient demand is actively underway in various fields. In particular, as the share of renewable energy continues to expand for the growth of distributed energy and small-scale distributed power sources become more widespread, it is time to rapidly secure technologies for grid stabilization. Currently, most distributed power sources consist of solar and wind power, and solar power, which accounts for about 60% of this, is mainly connected to the distribution system. Therefore, large-scale solar power generation can cause voltage problems in the distribution system. Generally, to solve voltage problems, the voltage of the distribution system is stabilized by installing an Energy Storage System (ESS) and limiting the output of solar power plants. Such voltage control methods involve installing ESS on distribution lines to control voltage or limiting the output of solar power generation due to concerns that the voltage at the Point of Common Coupling (PCC) terminal caused by solar power generation may exceed the allowable range (1.038 p.u.). However, at a time when the widespread adoption of large-scale solar power generation is expected, there is a problem that voltage control through ESS may face limitations. The background technology of the present invention is disclosed in Korean Registered Patent Publication No. 10-2200296 (published Jan. 8, 2021, Photovoltaic power generation device). The information described above disclosed in the background technology of this invention is intended only to enhance understanding of the background of the present invention and may therefore include information that does not constitute prior art. FIG. 1 is a block diagram showing a photovoltaic power generation device according to one embodiment of the present invention. FIG. 2 is a graph showing the result of performing voltage control through a photovoltaic power generation device according to one embodiment of the present invention. FIG. 3 is an exemplary diagram showing the power output of a solar power plant to which a solar power generation device according to one embodiment of the present invention is applied. FIG. 4 is a flowchart for explaining a solar power generation method according to one embodiment of the present invention. Hereinafter, a photovoltaic power generation device and a control method thereof according to the present invention will be described with reference to the attached drawings. In this process, the thickness of lines or the size of components shown in the drawings may be exaggerated for clarity and convenience of explanation. Furthermore, the terms described below are defined considering their functions in the present invention, and these may vary depending on the intention or convention of the user or operator. Therefore, the definitions of these terms should be based on the content throughout this specification. FIG. 1 is a block diagram showing a photovoltaic power generation device according to one embodiment of the present invention, FIG. 2 is a graph showing the result of voltage control performed through a photovoltaic power generation device according to one embodiment of the present invention, and FIG. 3 is an example diagram showing the power output of a photovoltaic power plant to which a photovoltaic power generation device according to one embodiment of the present invention is applied. The present invention relates to a photovoltaic power plant connected to a distribution system, which is composed of a plurality of photovoltaic power generation devices. Some of the photovoltaic power generation devices perform PQ (active power/reactive power) control to perform voltage control, while other photovoltaic power generation devices perform MPPT (maximum power estimation) control to supply power to the distribution s