Utilities developed in the past good processes and tools for the setting development task. By using standard calculation sheets that are based on a consistent setting philosophy the quality of protection settings can be guaranteed. But still, statistics show that many misoperations can be traced back to wrong settings (28%) or firmware problems (20%) [NERC Protection System Misoperations Task Force 2013]. The proposed paper reports on a project that used a real time digital simulator (RTDS™) for hardware in the loop testing to verify the correct relay settings and relay behavior on a 500 kV transmission line. During the project relay setting problems as well as firmware issues were discovered and could be resolved before the deployment of the relay scheme. The paper makes a case that hardware in the loop testing has become an economical option for the verification of the correct relay scheme behavior not only for the high end applications. This is based on the fact that automation can help during the testing and analyzing of the test results and can so lower cost and time to perform a sophisticated relay test. By evaluation the consequences of a misoperations against the cost of hardware in the loop testing, it can be shown that of hardware in the loop testing has become an economical method in the relay setting development process and verification of a correct relay application. This is particular true for utilities that own real time digital simulator hardware. The paper will discuss some of the findings and show how automation enabled the processing and reporting of over 3000 test in two week.
Juergen Holbach, Quanta Technology