VOLTAGE CONVERTER Russian patent published in 2003 - IPC

FIELD: electrical engineering; switch-mode converters for overcurrent protection of semiconductor power devices. SUBSTANCE: voltage converter has power amplifier, protective element incorporating current sensor, rectifier, threshold element, asynchronous-reset synchronous D flip-flop, as well as AND gate coupled with logical signal processing unit connected to master oscillator; output of the latter is connected to first input of logical signal processing unit and through pulse-width modulator, to first input of AND gate whose output is coupled with second input of logical signal processing unit; rectifier output is connected through threshold element to one of inputs of flip-flop whose output is connected to second input of AND gate. Mentioned power amplifier, rectifier, and logical signal processing unit are n-phase devices and protective element is provided with newly introduced (n 1) current sensors and n-phase demagnetizing device; input of each of n current sensors is inserted in current circuit of respective phase of n-phase power amplifier; output of each current sensor is connected to respective input of n-phase demagnetizing device whose outputs are connected to respective inputs of n-phase rectifier. D input of asynchronous-reset synchronous D flip-flop is used to pass signal for resetting this flip-flop to original position, its synchronizing input being connected to master oscillator output; each of n outputs of logical signal processing unit is connected to respective n control inputs of n-phase power amplifier; logical signal processing unit functions to cut off power amplifier transistors when flip-flop assumes state prohibiting signal passage from output of pulse-width modulator through AND gate to second input of logical signal processing unit. EFFECT: enhanced reliability. 1 cl, 2 dwg