Fuzzy control of ASMES to improve transient power system stability

In this paper we propose a new structure of SMES using a PWM current source inverter (CSI) by adopting a robust method based on the fuzzy logic for generate a modulation index and shift angle which allowed the reactive and active power exchange control in the four quadrants. Two independent fuzzy controllers are assigned, one for the frequency control and another for the terminal voltage control. Speed deviation (Δω) and acceleration (Δω´) of the synchronous generator are taken as the inputs signals to the fuzzy frequency controller (FFC). The terminal voltage deviation (ΔV_t) and it derivative (ΔV_t˙) are considered as the input of the to fuzzy voltage controller (FVC). Simulation results show that the proposed method of control can ensure transient stability of a single-machine-infinite-bus system under a large sudden fault.