Voltage and Reactive Power Regulation With Synchronverter-Based Control of PV-STATCOM

Abstract

This paper presents a synchronverter based photovoltaic (PV) system as STATCOM (PV-STATCOM), in which inverter exchanges active and reactive power with the grid. The proposed system provides reactive power compensation during daytime as well as nighttime. Additional operating modes for PV-STATCOM are proposed to enhance its capability. The proposed controller is compared with conventional control based PV-STATCOM on the basis of its performance with different tests. The key difference between conventional control and synchronverter is that synchronverter emulates inertia to control the frequency and voltage of the system. It is observed that the proposed system reduces frequency deviation and provides satisfactory regulation of the point of common coupling (PCC) voltage during full STATCOM mode and partial STATCOM mode. The low voltage ride through (LVRT) test is also performed on the proposed system. In the weak grid situation, the proposed PV-STATCOM performs in a more stable manner than the conventional PV-STATCOM in both reactive power and PCC voltage control mode. The study is performed on EMTDC/PSCAD simulation software. Real Time Control Hardware In Loop (CHIL) test is performed on Real Time Digital Simulator (RTDS) with a microcontroller to validate the proposed controller strategy and control design.

Keywords

• PV-based synchronverter
• grid-connected inverter
• synchronverter
• PV-STATCOM
• STATCOM
• virtual synchronous generator