The Design And Development Of Master Control Board On Relay Protection Testing Device

The relay protection equipments is an important testing tools to ensure safe and reliable operation of power systems. With the scale of modern Power Systems continues to expanded, the requirement of reliability and efficiency to The power system operation and management improved constantly, So the test of relay protection turns to more and more frequence and complicated. the rapid development of the computer technology, microelectronics and power electronics, driven the relay protection equipments development towards a computer-based, embedded and network direction. Because of the microprocessor relay protection has a lightweight, high performance and is easy to expand,make it bear greater market share and development prospects. The master control board of relay protection testing device is one of the core components of the microproecssor, it responded to the host computer's speed and precision of the signal source directly affects the performance of protection devices.The paper analyse the functional requirement of master control board and present the choice of main chips in details;besides posed the overall framework and analysed the principles of DDS. introducing some comm improved DDS algorithm and selected a kind of algorithm according to application requirement which meet the actual needs of the project,e demand. The constituent parts of the hardware was described in the form of module meanwhile describles the software's overall structure, as well as the realization of the interrupt and the design of serial driver is also introduced, the algorithm to the rectification of AD, and the design of driver to the network is also ilustrated, finally the internal communication protocol of the whole system is introduced.The function of master control board on Relay Protection Testing Device is abundant,it can achieve 12 channels analog outputs,8 channels digital inputs and 8 channels digital outputs. The basic analog waveform covers sine wave, triangle wave, square wave, and user-defined waveforms,besides use of the DSP's high-speed processing power to generate the harmonic waves by user specified.the maximum order is up to 20 times of harmonics.its available network port, serial port 232 make you can easily communicate with the host computer.