| Abstract: | The performance of a conventional two-electrode type precipitator collecting high resistivity dust can be improved by pulse energization. Pulses of a suitable duration and repetition rate superimposed on the DC voltage permit higher peak-voltage without sparkover, improve particle charging and current distribution, and allow independent regulation of the precipitator voltage and current. A considerable quantity of energy, however, is required for each pulse to charge the precipitator to the pulse voltage level. For high pulse voltages only a minor part of this energy is necessary for the discharge current in the precipitator. For reasons of economy, the recovery of the energy stored in the precipitator capacitance during each pulse is therefore extremely important for pulse energization of large precipitators. An energy conserving pulse generator with pulse transformer, a pulse initiating switch element, and a feed-back diode for the energy recovery is described. The design and the instrumentation of a pilot precipitator specially developed for the comparison of different kinds of precipitator energization are outlined. The ability of the applied pulse energization system for controlling the corona discharge current independently of the precipitator voltage is demonstrated. Further, results from field tests showing the performance of the system under operating conditions are presented. |
