Premium Power Park (PPP) is a technical solution to solve the regional high-quality power supply problems. The technical optimization method is the premise of planning and constructing. To meet various power requirements of different customers, the concept of process immunity time and sag immunity is lead up in this paper. Considering the response characteristic of process to sag, physical parameters and their variation, and acceptable resulting status of customer, the methods of quantification for customers’ demands and classification for power quality level are proposed. On this basis, optimization model is established by constraints of customers’ requirement and taking the minimum cost as the objective. And its corresponding algorithm based on Tabu search method is researched. The proposed method is applied to a typical PPP and it is proved to be accurate and valid. The results show that this method can meet each customer’s demand, meanwhile, ensure the minimum of total investment. And it provides a guarantee for engineering construction of PPP.