Input Power Factor Problem And Correction For Industrial Drives

ABSTRACT

The Asymmetrical Single - phase drive has an input power factor problem over its control range. With the race towards industrialisation, power networks in developing economies would face increasing power factor problems with extended application of these drives in industrial and traction systems. This project investigates the assertion that power factor of supply networks with multiple drives deteriorates with increased number of drives. The power factor problem is established analytically following a complete characterization of the AC input current of the drives. The methods of improving the input power factor of industrial drives are studied and the Pulse Width Modulation technique adopted for achieving power factor improvement for such industrial drives. The PWM scheme developed in the laboratory showed improved power factor. Generalised performance equations for the methods and their comparative controls, design and harmonic spectra are developed for application of industrial drives.