Chattering free sliding mode control law for the drive employing PMSM position control

The control system for position control of the drive employing PMSM based on the principles of sliding mode control and respecting the principles of vector control is presented. Designed controller is chattering free and complies with demanded control precision. Described control technique divides PMSM into two channels, which enable to control motor flux and torque separately. The controller is of the parallel structure, comprising a control loop for control of machine magnetic flux and parallel loop for control of the machine torque and rotor angle. To achieve demanded precision and to eliminate control chattering a smoothing integrator is introduced into both parallel controllers and furthermore the signnm function is replaced by a proportional high gain in the final version of the controllers. The simulations and preliminary experimental results indicate that the control systems yield the desired robustness and more complex investigations are recommended.