Practical Simulation Method of Digital Relay at C Source Code Level Based on PSCAD/EMTDC

Abstract

C source codes can be embedded into custom simulation models in PSCAD. Choosing this interface technology can realize closed-loop simulation at source code level for digital relays. The paper improves both calling interface and data interface, which are two keys of interface technology. The calling interface is implemented by calling a FORTRAN function in the script of custom modules. It makes debugging C source codes much simpler. The data interface is implemented directly by the input and output ports of custom modules, which avoids the use of complex public arrays. The proposed method is especially suitable for the transition stage from principle study to device development. An actual distance relay module written in C language is taken for an instance. The test case shows that the method can be used to verify C source codes in an actual relay flexibly and simply. Developers can validate the source codes independent of a physical device, which will enhance the efficiency greatly.

Keywords::

• PSCAD
• protection logic
• C language
• custom modules
• C source codes
• simulation

Additional information

Funding

This work was supported in part by the Shandong Provincial Natural Science Foundation, China, under Grant ZR2014EEM039.

Notes on contributors

Yiqing Liu

Yiqing Liu received the B.S. and M.S. degrees in electrical engineering from Tianjin University, Tianjin, China, in 2000 and 2003 respectively, and the Ph.D. degree in electrical engineering from Shandong University, Jinan, China, in 2012. He is the corresponding author of this paper. He is currently an Associate Professor with the School of Electrical Engineering, University of Jinan, Jinan, China. His fields of interest are power system protection, power system simulation and protective relay in smart substation.

Qifan Yang

Qifan Yang graduated from Shandong Electric Power Junior College, Jinan, China, in 2012. He currently is a graduate student in University of Jinan, Jinan, China. His main research interest is relay protection.

Guobin Chen

Guobin Chen received the B.S. degree from the School of Electrical Engineering, University of Jinan, Jinan, China, in 2016. He is currently a graduate student in University of Jinan, Jinan, China. His main research interest is relay protection.

Yunjin Shen

Yunjin Shen received the B.S. degrees in electrical engineering from University of Jinan, Jinan, China, in 2017. Her main research interest is relay protection.

Weicong Gao

Weicong Gao received the B.S. degrees in computer engineering from Tianjin University, Tianjin, China, in 2000, and the M.S. degrees in electronics and communication engineering from Shandong University, Jinan, China, in 2012. She is currently an Associate Professor with the School of Information Engineering, Shandong Vocational College of Foreign Affairs Translation, Jinan, China. Her main research interest is embedded systems and computer applications.