Title: Electrical Design of Qingyang Zhengning 330kV Substation ABSTRACT In order to meet the growing load of the southern region in Qingyang district, a new mechanized integrated 330kV substation is required to be constructed. This new substation would meet Zhengning coal mining industry’s development needs and requirements of the construction of power plant at the coalfield, on the basis of construction plan of Zhengnan coalfield. The new substation would also meet the demands of power supply to the Shaanxi Province while increasing the construction of power supply of Southern power grid therefore to make its structure more reasonable and to improve the system’s stability and reliability. The thesis is to design a mechanized integrated 330kV substation based on the original data. To determine the main wiring program after comparisons of reliability, economy and flexibility; To determine equipments such as transformers, circuit breakers, isolating switches, wires, current transformer and lightning protection facilities, following calculations of short-circuit electrical current. To configure the main protection and back-up protection and other related protective devices for the transformers. The design of substation is provided with reliability, economy and practicality.