The intelligent manufacturing of power systems has led to many challenges. The cyber-physical system (CPS) was introduced to solve the problem of insufficient integration of equipment and systems. It brings advantages, but also risks. In the distribution network CPS, malicious attacks on the PC-PLC communication network can cause significant incidents and affect system safety. The paper discusses two challenges, of possible mutated virus attacks and multi-delay in the PC-PLC coupled network. We present for the first time a virus-mutation and multi-delay propagation model. Then, to effectively control the virus propagation in the network and minimize the cost, the paper proposes five control measures, introduces their possible control combinations, and solves the optimal control problem with the Pontryagin maximum theorem. Finally, simulations verify the optimal control strategies for all combinations. By comparing the effects of maximum control, minimum control, average control, and optimal control, the optimal control strategy has been proven to be effective.