Inventors:
Conrad H. Hoeppner - Indialantic FL
Assignee:
McNeil Corporation - Akron OH
International Classification:
H02P 540
Abstract:
Power control apparatus and method for controlling polyphase excitation of a polyphase load. A first sequence of timong pulses are generated to represent each zero level voltage crossing of every phase voltage from a polyphase voltage source. After each of the predetermined numbers of the timing pulses has been generated, an energizng pulse is generated having a width of a predetermined duration. A set of power switches is provided coupling the polyphase source to the load via a set of load lines. The power switches are all rendered conductive to selectively couple phase voltages from the polyphase source to the load by each energizing pulse. This causes excitation of the load via repeating sequences of intermittent power pulses, with each power pulse being comprised of a selected grouping of the phase voltages from the polyphase voltage source. The source phase voltages comprising each group are associated in time with one another on the load lines and are: (1) of a selectable number, and (2) of a selectable permutation of phases. Variance of the rate at which the energizing pulses are generated and of the value of the predetermined duration of the pulse width determines the selected number of and the phase of the voltages in the power pulses.