Application of different types of high-voltage supplies on industrial electrostatic precipitators

Investigations of the requirements for high-voltage (HV) power supplies for zones within an electrostatic precipitator (ESP) were conducted with regard to the properties of different technologies for HV generation. The zones of an ESP show different electrical behavior and efficiency. This is a result of: 1) the different dust loads of the zones; 2) the particle size and properties; and 3) the possibility of charging the particles in the entire zone using suitable technology. An overview of common and new topologies of HV supplies and their typical properties is given. It is shown how these properties can be used to match the requirements of the different zones of an ESP regarding the actual operating conditions. Large particles and high dust loads can be addressed effectively using high-frequency dc power supplies. Fine particles, however, can be separated even more efficiently by pulsed power supplies. Additionally, the power consumption of different HV sources has been investigated in relation to the separation efficiency. Experimental results were obtained on an industrial ESP containing 3 zones in a sinter plant and on a large scale precipitator in a fossil power plant, containing 30 zones. It was shown that a high frequency IGBT inverter combined with a microsecond-pulsed power supply significantly improved the overall performance of the precipitator.