A switch-mode power amplifier based on a cascaded multicell multilevel circuit topology is introduced in the paper. Due to the Carrier-Based phase-shifted modulation of the individual switching cells, the output voltage ripple of the total system is considerably small. Compared with traditional class- AB amplifiers that are very poor at efficiency, the proposed amplifier has the efficiency of 90% at the smaller distortion level. A multilevel class-D amplifier’s mathematic model is analyzed. The paper lays emphasis on the design of the sliding mode control and deducts the parameters, and then develops a 2kW cascade multilevel class-D power amplifier adopting sliding mode control. The research results show that this kind of amplifier increases the system bandwidth, which provides the system with fast following performance and stability, high efficiency, and low THD value of output signals.
Ripple Compensation for a Class-D Amplifier