STUDY OF WLB-2000 DIGITAL RELAY BASED ON DSP FOR HIGH-VOLTAGE TRANSMISSION LINE

摘要

A microcontroller with generic CPU has difficulty in satisfying some special requirements for protection, such as high-speed calculations and wavelet analysis application in protective relay. A new (type WLB-2000) digital protection system for high-voltage transmission line has been built with digital signal processor (DSP). A whole protection device scheme based on DSP chip of TMS320C32 is presented in detail. The scheme provides zero-sequence overcurrent protections, phase-to-phase and phase-to-ground distance protections, especially for in the second zone of the protection line, which can accelerate the protection operation without pilot channels after the receiving-end circuit breaker trips, fault locator, and data communication functions. The prototype shows that the mode can not only reduce hardware design workload, but also reduce the software development period. Especially because the algorithm speed and precision are greatly enhanced, the relay offers greater protection operation precision for short high-voltage transmission lines of one or more than 1 km.