Abstract: In view of the shortcomings of the impedance switching mode in the current low voltage circuit breaker short-circuit testing,electrical-life testing and so on,an intelligent impedance controller was proposed.Firstly,this paper analyzes the function of the intelligent impedance controller based on the actual use of the test equipment,and then discusses in detail how to carry out the intelligent control,including the calculation of the impedance by using the test parameters and the realization of the impedance automatic switching by using the look-up table method and IO correlation.Then,according to the functional decomposition of the controller,the hardware and the corresponding software are designed on the hardware platform.The intelligent impedance controller designed in this paper is tested and verified in the MCB electrical-life equipment,it realizes the function of impedance automatic switching,and overcomes the shortcomings of traditional impedance switching.

Key words: impedance switching, intelligent impedance-controller, look-up table, IO correlation