A hybrid algorithm for reactive power optimization based on bi-level programming

This paper established a bi-level programming model for reactive power optimization, considering the feature of the grid voltage-reactive power control. The targets of upper-level and lower-level are minimization of grid loss and voltage deviation, respectively. According to the differences of two level, such as different variables, different solution space, primal-dual interior point algorithm is suggested to be used in upper-level, which takes continuous variables in account such as active power source and reactive power source. Upper-level model guaranteed the sufficient of the reactive power in power system. And then in lower-level the discrete variables such as taps are optimized by random forests algorithm (RFA), which regulate the voltage in a feasible range. Finally, a case study illustrated the speediness and robustness of this method.