Relative Voltage Control of the Wind Farms Based on the Local Reactive Power Regulation

Yangyang Zhao,Xudong Sun,Jianyun Chai

doi:10.3390/en10030281

Abstract

The fast and coordinated voltage control of distributed nodes inside a large scale wind farm is a stringent issue. To achieve the reactive power compensation without a dedicated upper communication system, this paper proposes a relative control strategy based on the local reactive power regulation. This method can realize the voltage coordination of the key equipment and feeder line nodes, on the basis of the relative voltage observations. Firstly, the stability analysis of a certain wind farm with pre-known parameters and structure is studied under the wind power fluctuations. Secondly, the optimal capacity configurations of the reactive power compensators are discussed, with multiple nodes inside the wind farms. Simulation results of a specific wind farm in North Hebei, China, validate the effectiveness of the proposed control, which is equipped with fast and stable voltage dynamic responses, as well as local reactive power compensations without remote communication.

Highlights

Fluctuations of the distributed voltages and reactive power are one of the most common problems in the operation of large scale wind farms, as the internal voltages inside wind farms can be affected by the network parameters and wind speed under normal operations
With the increasing amount of doubly-fed induction generator (DFIG) and permanent-magnet synchronous generator (PMSG) wind turbines installed in the wind farms, significantly more research has focused on the voltage regulations of the generator terminals and the local compensation of the distributed reactive power [3,4]
In order to improve the dynamic performance of the internal voltage regulation inside the wind farm, as well as realize the local reactive power compensations without remote communication, the approach in this paper proposes compensating the reactive power based on the observations of local relative voltage errors

Summary

Introduction

Fluctuations of the distributed voltages and reactive power are one of the most common problems in the operation of large scale wind farms, as the internal voltages inside wind farms can be affected by the network parameters and wind speed under normal operations. Centralized reactive power compensators are widely used at the point of common coupling (PCC) of the wind farms, such as a static var compensator (SVC), static synchronous compensator (STATCOM), etc. With the increasing amount of doubly-fed induction generator (DFIG) and permanent-magnet synchronous generator (PMSG) wind turbines installed in the wind farms, significantly more research has focused on the voltage regulations of the generator terminals and the local compensation of the distributed reactive power [3,4]. The hierarchical voltage control methods, based on the reactive power regulations of the variable-speed constant-frequency (VSCF)

Objectives

Methods

Results

Conclusion