Li Yinhong

An integrated power system relay coordination software

The development of new generation software for relay coordination is the focus of the relay protection industry and related research fields. In this paper, an integrated power system coordination tools called Computer Aided Coordination for Relay in Power System with Graphical Interface is presented. A brief description of the development of setting tools is given first, then the whole structure and function division are introduced. Finally, the new tendency of relay coordination software is put forward.

A study on optimal coordination of definite-time relay based on genetic algorithm

Relay optimal coordination is of great significance in bringing the role of the protection device into full play, improving the integral performance and ensuring the best integral effect of the protection system. In view of the problems existing in optimal coordination of definite-time relay, this paper presents a new method based on the genetic algorithm. In this method, a new coding technique, called constraint interval coding, is adopted to enhancing the efficiency and precision of optimization. The result of an example shows that the new method is effective for optimal coordination of definite-time relay. The application of the new method in the multi-loop network and the mixed protection system with inverse-time relay and definite-time relay is discussed further.

A study of integrated adaptive relaying system for large-scale mixed power network

Developing adaptive relaying system is of great significance in ensuring the protection always has the most suitable settings for each operating state, avoiding mal-operation and relieving protection engineer completely from tedious coordination work. In view of the problems existing in developing adaptive relaying system for large-scale mixed network, this paper presents the design of an integrated adaptive relaying system. In the system, two adaptation modes are applied to improve the real timeliness and real time verification is adopted to keep the coordination among relays. The paper introduces the main structure and function division of the system. And some solutions of the pivotal problems of the system are also discussed in detail.

A study on the simple loop formation method of modern power system

Formation of all simple loops is a pivotal step of influencing the efficiency of break point determination algorithm. In view of the characteristics of modern power network loop distribution, based on the method of fundamental loop linear combination, a new simple loop formation method is presented in this paper in which combining a formed simple loop or complex loop with a fundamental loop can form a new simple loop. The new method can not only eliminate most invalid loop combination, but also decrease calculation quantities. The result shows the effectiveness of the new method.