The design of high frequency power amplifiers using state-of-the-art semiconductor devices

The authors consider the design of power amplifier stages suitable for high-performance servo motor applications. They discuss some of the state-of-the-art devices which are suitable for high current conversion and how they can be successfully integrated into amplifier designs. Particular emphasis is given to the problems caused by transients and how these can be suppressed to ensure reliable operation. For some applications, the much lower drive requirements of the newer devices usually means that simplifications can be made in the drive circuitry; the vastly superior switching speed offers the possibility for lower losses or higher operating frequency, or both; and the superior safe operating area offers greater loading and overloading capability and minimization or elimination of protective snubber components. Modeling of the whole bridge arrangement, followed by simulation and practical tests, has resulted in a structured methodology for robust servo amplifier design