Stability of multi-generator power system with penetration of renewable energy sources

In this paper, the power system with penetration of renewable energy sources is represented as a multi-machine interconnected system. The power system comprises of conventional synchronous generators and renewable energy sources via rectifier-inverters. A novel controller has been proposed for the inverter that connects the renewable source to the grid while each conventional synchronous generator is equipped with an automatic voltage regulator (AVR) that can be accompanied by a power system stabilizer (PSS). The proposed inverter controller utilizes a dynamically varying gain such that the dynamics of the renewable power source is similar to that of the conventional synchronous generators. Subsequently, stability of the power system is achieved by employing a conventional damping controller. Simulation results on the IEEE 14-bus power system with the proposed renewable energy source controller are provided to show the effectiveness of the approach in damping oscillations that occur after disturbances are removed. The end result is a feedback controller that makes possible for power systems with penetration of renewable energy sources the application of conventional multi-machine stabilizing techniques such as PSS.