Control Strategy of Grid-connected and Islanding Operation for Turbo-generator Units Based on Improved Fuzzy PID Control

In order to improve the regulating ability of turbo-generator units under different operation conditions, a control strategy of grid-connected and islanding operation for the unit based on fuzzy PID controller is proposed. Firstly, the mathematical model of steam turbine and its regulating system is established, and then the structural characteristics and control performance of different control modes are analyzed in detail. Based on this, corresponding control strategies are selected to meet different control objectives of units under grid-connected and islanding operation. At the same time, this paper improves the fuzzy PID controller using particle swarm optimization algorithm with the intention of improving the dynamic response ability of the unit, in which the PID parameters can be adjusted adaptively in real time based on the optimized initial parameters. Finally, the grid-connected and islanding operating states of the unit are simulated and various kinds of disturbances are set. The results show that the proposed control strategy can meet the control requirements of the unit under different operation conditions, and the improved fuzzy PID controller has good performance.