Measurement-driven load change compensation for robust secondary voltage regulation

Voltage regulation ensures the reliable and efficient operation of power systems by maintaining voltage levels within specified limits despite changing load conditions. Modern grids integrating renewable energy sources face new challenges. These sources, such as wind and solar power, cause rapid power fluctuations. Furthermore, high-demand loads like electric vehicles could also result in very fast power variations. This paper explores an advanced control strategy related to the integration of Flexible AC Transmission Systems (FACTS) devices within an improved Secondary Voltage Regulation (SVR) based on an optimal linear quadratic control. The control strategy can compensate the effects of fast load variations, by exploiting the information provided by the Phasor Measurement Units (PMUs). The PMUs are, however, affected by non-idealities, which can reduce the compensation's efficiency. In the paper, the performance of the regulation strategy is assessed according to the two main PMU's characteristics: the report rate and the accuracy associated with the measurement results. The paper thus provides a walkthrough to properly select the characteristics and, thus, the cost of the PMU, according to the desired voltage regulation's performance.