Research on protection equipment with digital interface based on IEC-61850

A newly developed microcomputer relay protection with digital interface is presented. It adopts digital optical communication technology and Ethernet network instead of traditional metallic cable. Therefore it can highly enhance the anti-interference ability and reliability of the protections. The hardware structure and software pattern are introduced respectively. The new protection adopts the high-speed DSP TMS320VC33 as its hardware platform and RTL8019AS as the Ethernet controller. Task scheduling is based on multi-task mechanism. Ethernet communication task's priority is lower than the sampling task and the protection task but higher than the keyboard and display tasks. Switches among tasks are realized by dispatching and receiving signals. Some performance test results are presented in the end and prove the new protection's potential to be realized in the field in future.