HIGH-FREQUENCY SWITCHING-MODE POWER-AMPLIFIER FOR SHAKER ARMATURE EXCITATION

The paper presents the design and implementation of a switching-mode p ower amplifier for shaker armature excitation. First, the dynamic mode l of a current-source-driven shaker system is derived. Then a novel cu rrent-controlled PWM scheme is proposed for performing the switching c ontrol of inverter. To obtain good reference-current tracking-control characteristics over a wide frequency range, the feedback-current cont roller is augmented with a command-feedforward controller and a robust disturbance-feedforward controller. In the design of the disturbance- feedforward controller, the disturbance observer and robust-control te chnique are developed to make it practically feasible and have robust control performance. The design of the proposed controller is describe d in detail and practical limitations and the implementation of the cu rrent controller are discussed. Some measured results are provided to demonstrate the performance of the developed switching-mode power ampl ifier.