Power Supply Systems Using Synchronous and Asynchronized Generators with Predictive Controllers in the Context of Low Power Quality

Abstract

Distributed generation (DG) plants, when used in power supply systems, make it necessary to solve control problems for such systems for all possible operating conditions. The DG plants can employ low-power synchronous or asynchronized generators, which differ not only in design but also in automatic excitation control systems. The paper focuses on power systems with DG plants using synchronous and asynchronized turbine-generator sets; it also describes computer models of network components developed on the MatLab platform, including those of asynchronized generators with automatic voltage and speed regulation systems using a predictive control algorithm. The research aims to analyze the operating conditions of a power supply system with synchronous or induction generators equipped with automatic controllers and to find out the possibility of using predictive control algorithms for asynchronous generators. To this end, normal, emergency, and post-emergency conditions were simulated. A three-phase short circuit in the network and its tripping by relay protection were considered a disturbance. The obtained simulation results made it possible to formulate the following conclusions: the asynchronized generators, when used in DG plants, improve the power quality by reducing voltage harmonic distortions, and increasing stability margins; also, predictive controllers for synchronous and asynchronized generators improve the quality of control processes. Research on matching the settings of predictive controllers and developing self-tuning predictive speed and voltage controllers for asynchronous generators is advisable.