Research on Reactive Power Compensation Control Strategy of Flexible On-Load Voltage Regulator

The application of on-load tap-charger (OLTC) transformer technology has become the most direct and effective way to solve the voltage fluctuation of power grid. With the development of active distribution technology, the research focus of on-load voltage regulation technology has gradually turned to the development direction of arc free, fast and intelligent. This paper presents a flexible on-load voltage regulation topology based on power electronic technology. The flexible on-load voltage regulation (flexible OLVR) transformer is a combination of power electronic technology and traditional on-load tap-charger transformer, which can realize fast arcless switching, voltage step-less regulation, power regulation and other functions. In this paper, a new type of flexible on-load voltage regulation transformer is proposed. The OLTC switches of the device adopts the power electronic switch of anti-parallel thyristors, which can realize step, fast and arcless voltage regulation; the power electronic converter (PEC) module is connected to the primary side of the main transformer. At the same time, it proposed a new reactive power compensation control strategy, which could realize the functions of step-less voltage regulation and reactive power compensation. In the end, the rationality and validity of the proposed topology is tested and verified by simulations and experimental tests.