Discrete monkey algorithm and its application in transmission network expansion planning

Monkey algorithm (MA) is one of the evolution algorithms originally developed for optimization problems with continuous variables. In this paper, a discrete monkey algorithm (DMA) was proposed for transmission network expansion planning, one discrete optimization problem. It includes the representation of solution, the modification of objective function, climb process, watch-jump process, cooperation process, somersault process, stochastic perturbation mechanism and termination criteria. Large-step and small-step climb process are designed to avoid the disordered climb direction during the MA optimization process. Cooperation process and stochastic perturbation mechanism are also introduced to improve computational efficiency. The proposed method is applied to a 18-bus system and the IEEE 24-bus system. Numerical results demonstrate that DMA has powerful computational capability and is capable of solving different dimensions of expansion planning problems efficiently with small population size.