PI-controller Fuzzy Tuner Based on Transient Quality Estimation to Control DC Drive Speed

The quality improvement of a DC drive speed control is the scope of this research. Classical PI-controllers with constant parameters does not provide high quality of transients for all DC drive functioning modes due to the motor nonlinearity and parameters nonstationarity. In this regard, there is a need to develop control systems, which take this fact into account and, to some extent, compensate it. The existing methods to develop DC drive adaptive control system are analyzed. It is concluded that the most promising way to solve this problem is to apply fuzzy logic to implement a PI-controller parameters adjuster. A comparison of the existing fuzzy tuners is made, and their shortcomings are found. A new fuzzy tuner is proposed and implemented taking into consideration the transients quality requirements. A model of a DC drive of NI-ELVIS II test bench is developed to conduct experiments. Full-scale experiments are also performed using this test bench. The results show that the proposed tuner, which uses an overshoot and a transient time estimation as input variables, is able to reduce the overshoot value by 15% comparing to the classical speed PI-controller and by averagely 10% in comparison with the exiting tuners under the conditions of the DC drive parameters nonstationarity, while the transient time remains the same.