Software Design of Dual CPU Controlled Digital Protection Device

Abstract The requirements of device under the multi-mission of monitoring, protecting, controlling and communicating is discussed in this paper to bring forward a design of dual CPU structure with ARM & DSP for microprocessor protection. Via the comparative analysis of several common algorithms, the algorithm of FFT, which can make the controlling of calculation accuracy easier and has a filter feature inherently, is selected to analyze the sampling data of protector and calculates relative electrical parameters. Relevant program is written for distance protection in 110 kV transmissions, then debugging on software and hardware is made. The results show that the design of DSP & ARM based-microprocessor protection presented in this paper is feasible; such a device has simple and reliable circuit structure and is expandable in both software and hardware.