Overview of Digital Control Techniques

Abstract

This chapter discusses the classical and advanced digital control techniques, including predictive control and examines the operating principle of these control techniques with an intuitive example of generator or grid current control. When closed, a switch allows the passage of any amount of current without any on‐state voltage drop. The power diode belongs to the family of uncontrolled semiconductor devices because its switching on and off instances depend on natural commutation and power circuits. This device has been widely used in industrial applications from the 1950s and is still widely used. More powerful digital control platforms are expected to be developed in the near future, thus resulting in lower costs and higher computational capacity than existing control platforms. Hysteresis current control does not require the system parameters, converter model, or prior knowledge of the user, thus making it one of the simplest and robust current control techniques. The relative magnitudes of these error signals are then used by a lookup table to generate the switching signals to the converter. To implement these methods on digital platforms, a high‐sampling frequency is needed to force the variables within the hysteresis band limits.