A Generalized Controller for Electric-Spring-Based Smart Load With Both Active and Reactive Power Compensation

With the electric spring (ES) being practically evaluated by utility companies in power grids, there is a need to explore its practical implementation aspects of general applications. In this paper, we propose three interior angle control principles for the ES. Systematic analysis and comparative study show that these three control principles lead to different smart load (SL) performance. The operating characteristic curves and distinctive features/advantages of the SL using these three control methods are analyzed and explained. A generalized controller structure suitable for the implementations of all these three angle control schemes is presented. It is practically shown that the same controller structure can be programmed to implement these three angle control strategies. This outcome is the first step to realize a programmable ES-based SL for providing multiple functions.