Reactive power control of an isolated wind-diesel hybrid power system based on SVC by using sliding mode control

Due to the problem of voltage fluctuation resulting from the reactive load changes and generation sources in the isolated wind-diesel hybrid power system, a control strategy of using Static VAR Compensator (SVC) is proposed to maintain the system terminal voltage. To improve the performance of SVC, here we use the sliding mode algorithm to design the additional SVC robust controller. So firstly, the model of isolated wind-diesel hybrid power system with SVC is established, and then using the sliding mode algorithm - by selecting appropriate proportion switching surface and reaching condition - to construct the robust controller of SVC. Finally, the simulation model is built based on the MATLAB simulation platform. The numerical simulations show that, for the different kinds of disturbances in wind and load, the designed additional SVC sliding mode controller can effectively restrain the voltage fluctuation, and has better transient stability compared with the traditional SVC controlling strategies.