Transformer Protection Device Based On Dsp Design

Power transformers are important facilities in power system. They are used in electricity generating transmitting distribution and other taches of power system. Their safety running determines weather the whole power system can operate steadily and continuously. So high-performance and secure relay protection sets are needed for power transformers. Especially microcomputer relay protection sets, with software's agility, find a wide application in protection of power transformers.In this paper, a microcomputer relay set for power transformer is designed under summarizing the protection theory. In this design, a digital signal processing chip (DSP) is used to satisfy the request of real-time processing for faults of power transformer. A CAN-BUS communication and RS485 serial communication, which controlled by single-chip, are supplied for power system communication. Programmable logic devices are also used for simplifying the periphery circuit' design of CPU. With the agility of software, the set is prepared with over-current differential protection, second harmonic restraint differential protection, and zero sequence protection, overload protection and self-check functions.