FPGA implementation of a signal synthesizer for driving a high-power electrostatic motor

This paper describes a motor driver circuit for a high-power electrostatic motor using Field Programmable Gate Array (FPGA). Electrostatic actuators are popular in the field of micron or nano technologies but some high-power electrostatic motors have been developed for normal-sized applications. Dual Excitation Multiphase Electrostatic Drive (DEMED) is one of the strongest actuators among them. There are various driving methods for the motor (DEMED), however, regardless of driving methods, developing driving circuits is one of the difficulties for practical applications. To operate the motor, one or two three-phase signals are required and amplitudes of them must be a few kV. Hence multi-channel signal synthesizers and high-power amplifiers are needed for driver circuits. In addition, portability is required for some applications as well. In this research, therefore, quad Direct Digital Synthesizers (DDS) are built inside the one FPGA. In the performance evaluation, this driver circuit generates motor driving signals based on the position command that is given by a higher-level controller. It is confirmed that the electrostatic motor operates following reference position data, by using this FPGA-based motor driver.