Model based PID control design for bus voltage regulation in multi-machine power systems

摘要

Complexity and severe nonlinearity of multi-machine power systems make it difficult to design a control input for voltage regulation using modern control theory. This paper presents a model based PID control scheme resulting in bus voltage regulation to a desired value. To this end, a model is constructed using the input and output data which are obtained using the Transient Security Assessment Tool (TSAT); the input is assumed to be applied to the grid through the Static Synchronous Series Compensator (STATCOM) and the output from the grid is a bus voltage. On the ground of the model, it is identified which open loop poles of the system make the response to the step input oscillatory. To reduce the oscillatory response effectively, a model based PID control is designed in which the gains are adjusted in a way that the poles are not problematic any more in the closed loop. Simulation results show that the proposed PID control dampens the response effectively.