A Control Strategy Based on Fuzzy Logic for Levelling Load Power Fluctuation by Using Superconducting Magnetic Energy Storage

The control strategy based on fuzzy logic is proposed for levelling the load power fluctuation and compensating the reactive power by using the superconducting magnetic energy storage (SMES) equipped near to the consumer. Then, its control effects are discussed by simulation. The obtained results are summarized as follows. (1) The conditions with respect to the levelling of the active power in the source line and the energy stored in the SMES are introduced. Then, the production rules on these conditions are constructed. (2) The estimation value LD of levelling the active power in the source line is proposed in addition to the estimation value v of following the sustained component. (3) Provided that the base of the triangle in the menbership function is set to 1.05 for the load power fluctuation investigated, the most preferable result can be obtained when the heights of triange are 0.01 and 0.6 in the rule 1 and the rule 2, respectively. (4) Comparing with the control results by using the estimation function, the estimation value v with the fuzzy control is less than that with the estimation function regardless of the capacity of the SMES. Therefore, it is clarified that the levelling of load power fluctuation can be achieved by the fuzzy control better than by the estimation function.