Power system protection devices approval process and their benefits to Saudi Electricity Co

Saudi Electricity Company (SEC) had adapted the intensive Protection Relay Approval Process for the protection devices to be used on their network. This process had coincided with the advent of numerical relays in SEC network in 1999. This paper gives details of the process adapted for the protection relay documents and for the process of device testing to identify the problems embedded in hardware/software which were difficult to be identified during type tests. Numbers of abnormalities were noted and got corrected by the manufacturer prior to approval of the relay. Numerical relays have problems due to miniaturization in hardware and associated relay software algorithm and their frequent upgrades. And also due to heavy competition between the relay manufacturers to develop advanced relays in short time. Operational tests conducted on different types of protection devices from different manufacturers, and the test areas where more attention is needed is described. The paper lists down the shortcomings identified in the relays and their corrections. The paper also describes the protection laboratory setup for adapting such process. And use of real time digital simulator (RTDS) for carrying out such tests.