AC speed servo system with α-parameter ultimate sensitivity method based fuzzy reasoning auto-tuning approach

In AC servomotor drive systems, in some cases, mechanical resonant vibration is generated according to the load conditions. In order to overcome this problem, the authors introduced a load speed feedback method, and then prevented shaft vibration. In order to compensate three control gains which are PI proportional constant, PI integral time constant and load speed feedback gain, the α-parameter ultimate sensitivity method (which is based on the partial model matching method) is proposed. The feature of this method is that both the response and the stability of the AC servomotor drive system are secured by setting only one parameter α. Moreover, a fuzzy reasoning logic algorithm is applied to compensate the parameter α. This proposed control strategy does not require any kind of knowledge or information on system parameter tuning techniques. In this paper, the effectiveness of this advanced autotuning control scheme in an AC servomotor system is evaluated and verified by computer simulation