Frequency Stability and Coordinated Control Strategies of UHV AC/DC Receiving End Grid

Abstract

In order to improve the control accuracy of UHV AC/DC receiving-end grid for DC blocking faults, method of making online strategies that coordinate different control measures including emergency DC power support, pumped storage control and accurate load shedding, is proposed considering safety and stability of system frequency and transmission sections. This paper analyzes the coordination principle of different control measures and processes frequency emergency control calculation first, assisted by overload sections corrective control as frequency meets stability requirement. The comprehensive evaluation indexes are present to formulate coordinated control strategies by decoupling and aggregation, which make grid frequency return stable and also eliminate the hidden overload dangers of transmission sections. Based on the typical operating mode of actual grid, the effectiveness of the proposed coordinated control decision making was verified.