Research on the Influence Factors and Coordinated Control Strategies between Unit and Grid for Isolated Power System

Ge Jin, Xiaomei Chen, Yongxin Feng, Shaoxiang Deng, Hanting Yan, Zexiang Cai

Electric Power Research Institute, Guangdong Power Grid, Guangzhou, China.
School of Electric Power, South China University of Technology, Guangzhou, China.

DOI: 10.4236/epe.2013.54B086                

Abstract

As the existing coordinated control strategies between grid and unit have limitations in isolated power system, this paper introduces new coordinated control strategies which can improve the stability of isolated system operation. This paper analyzes the power grid side and unit side influence factors on the isolated power system. The dynamic models which are suitable for islanding operation are applied to simulate and analyze the stability and dynamic characteristics of the isolated power system under the conditions of different load disturbances and governor parameters. With considering the differences of frequency characteristics between the interconnected and isolated power system, the adjusting and optimization methods of under frequency load shedding are proposed to meet the frequency stability requirements simultaneously in the two cases. Not only proper control strategies of the power plant but the settings of their parameters are suggested to improve the operation stability of the isolated power system. To confirm the correctness and effectiveness of the method mentioned above, the isolated system operation test was conducted under the real power system condition, and the results show that the proposed coordinated control strategies can greatly improve stability of the isolated power system.

 

Keywords

Isolated Power System; Coordinated Control Strategies; Under Frequency Load Shedding; Dynamic Frequency Characteristics; Speed Governor Parameter Settings

Conflicts of Interest

The authors declare no conflicts of interest.

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