| 摘要 |
electrical engineering. SUBSTANCE: former of synchronizing pulses can be employed to control thyristor converter on A C electrified rolling stock with regenerative braking, it is able to operate under heavy distortion of form of supply voltage without any static and dynamic errors. Former of synchronizing pulses incorporates instrument transformer, comparator, integrating element, phase-shifting element, former of reference pulses, sawtooth voltage generator, half-adder, storage and retrieval unit, comparison element, front pulse former and frequency divider. Output of instrument transformer is coupled to inputs of comparator and phase-shifting element which output is connected to inputs of sawtooth voltage generator and frequency divider via former of reference pulses and to second input of integrating element which first input is connected to output of comparator. Output of sawtooth voltage generator is coupled to second inputs of half- adder and comparison element. Output of integrating element is connected to first input of half-adder which output is coupled to first input of storage and retrieval unit which second input is connected to output of frequency divider. Output of storage and retrieval unit is coupled to first input of comparison element which output is connected to input of front pulse former and its output is output of former of synchronizing pulses. Application of integrating element makes it feasible to decrease effect of variation of supply voltage at moment of its transition through zero which in its turn raises accuracy of formation of synchronizing pulses which is technical result of invention. Results of simulation with model demonstrated that distortions of supply voltage related to multiple transition of it through zero do not lead to shift of synchronizing pulses relative to non-distorted form of supply voltage. EFFECT: raised accuracy of formation of synchronizing pulses. 3 dwg |
