Three-phase inverter control circuit

Claim 2

A three-phase inverter control circuit for producing gatecathode trigger signals for the inverter and corresponding extinguishing silicon controlled rectifiers, each having gate, anode and cathode electrodes, of a three-phase inverter circuit and applying the trigger signals to the extinguishing and inverter silicon controlled rectifiers in the proper sequence to energize the phase windings of a three-phase alternating current motor from a direct current supply potential source comprising, a variable frequency oscillator, means responsive to the output signals of said variable frequency oscillator for producing a repeating series of six equally spaced electrical timing signals, means responsive to the leading edge of each of said electrical timing signals for producing a corresponding gate signal pulse, means responsive to each of said gate signal pulses for producing three gate-cathode power pulses, and means for applying a respective one of said gate-cathode power pulses across said gate-cathode electrodes of each the said extinguishing silicon controlled rectifier corresponding to the said inverter silicon controlled rectifier to be extinguished, the said inverter silicon controlled rectifier next to be triggered conductive and the said inverter silicon controlled rectifier last triggered conductive.

Claim 3

A three-phase inverter control circuit for producing gate-cathode trigger signals for the inverter and corresponding extinguishing silicon controlled rectifiers, each having gate, anode and cathode electrodes, of a three-phase inverter circuit and applying the trigger signals to the extinguishing and inverter silicon controlled rectifiers in the proper sequence to energize the phase windings of a three-phase alternating current motor from a direct current supply potential source comprising, a variable frequency oscillator, a shift register circuit responsive to the output signals of said variable frequency oscillator for producing a repeating series of six equally spaced electrical timing signals, means responsive to the leading edge of each of said electrical timing signals for producing a corresponding gate signal pulse, means responsive to each of said gate signal pulses for producing three gate-cathode power pulses, and means for applying a respective one of said gate-cathode power pulses across said gate-cathode electrodes of each the said extinguishing silicon controlled rectifier corresponding to the said inverter silicon controlled rectifier to be extinguished, the said inverter silicon controlled rectifier next to be triggered conductive and the said inverter silicon controlled rectifier last triggered conductive.

Claim 4

A three-phase inverter control circuit for producing gate-cathode trigger signals for the inverter and corresponding extinguishing silicon controlled rectifiers, each having gate, anode and cathode electrodes, of a three-phase inverter circuit and applying the trigger signals to the extinguishing and inverter silicon controlled rectifiers in the proper sequence to energize the phase windings of a three-phase alternating current motor from a direct current supply potential source comprising, a variable frequency oscillator, a shift register circuit responsive to the output signals of said variable frequency oscillator for producing a repeating series of six equally spaced electrical timing signals, means responsive to the leading edge of each of said electrical timing signals for producing a corresponding gate signal pulse, means responsive to each of said gate signal pulses for producing three gate-cathode power pulses, and means for applying a respective one of said gate-cathode power pulses across said gate-cathode electrodes of each the said extinguishing silicon controlled rectifier corresponding to the said inverter silicon controlled rectifier to be extinguished, the said inverter silicon controlled rectifier next to be triggered conductive and the said inverter silicon controlled rectifier last triggered conductive.

Claim 5

A three-phase inverter control circuit for producing gate-cathode trigger signals for the inverter and corresponding extinguishing silicon controlled rectifiErs, each having gate, anode and cathode electrodes, of a three-phase inverter circuit and applying the trigger signals to the extinguishing and inverter silicon controlled rectifiers in the proper sequence to energize the phase windings of a three-phase alternating current motor from a direct current supply potential source comprising, a variable frequency oscillator, means responsive to the output signals of said variable frequency oscillator for producing a repeating series of six equally spaced electrical timing signals, a differentiating circuit responsive to the leading edge of each of said electrical timing signals for producing a corresponding gate signal pulse, means responsive to each of said gate signal pulses for producing three gate-cathode power pulses, and means for applying a respective one of said gate-cathode power pulses across said gate-cathode electrodes of each the said extinguishing silicon controlled rectifier corresponding to the said inverter silicon controlled rectifier to be extinguished, the said inverter silicon controlled rectifier next to be triggered conductive and the said inverter silicon controlled rectifier last triggered conductive.

Claim 6

A three-phase inverter control circuit for producing gate-cathode trigger signals for the inverter and corresponding extinguishing silicon controlled rectifiErs, each having gate, anode and cathode electrodes, of a three-phase inverter circuit and applying the trigger signals to the extinguishing and inverter silicon controlled rectifiers in the proper sequence to energize the phase windings of a three-phase alternating current motor from a direct current supply potential source comprising, a variable frequency oscillator, means responsive to the output signals of said variable frequency oscillator for producing a repeating series of six equally spaced electrical timing signals, a differentiating circuit responsive to the leading edge of each of said electrical timing signals for producing a corresponding gate signal pulse, means responsive to each of said gate signal pulses for producing three gate-cathode power pulses, and means for applying a respective one of said gate-cathode power pulses across said gate-cathode electrodes of each the said extinguishing silicon controlled rectifier corresponding to the said inverter silicon controlled rectifier to be extinguished, the said inverter silicon controlled rectifier next to be triggered conductive and the said inverter silicon controlled rectifier last triggered conductive.

Claim 7

A three-phase inverter control circuit for producing gate-cathode trigger signals for the inverter and corresponding extinguishing silicon controlled rectifiers, each having gate, anode and cathode electrodes, of a three-phase inverter circuit and applying the trigger signals to the extinguishing and inverter silicon controlled rectifiers in the proper sequence to energize the phase windings of a three-phase alternating current motor from a direct current supply potential source comprising, a variable frequency oscillator, a shift register circuit responsive to the output signals of said variable frequency oscillator for producing a repeating series of six equally spaced electrical timing signals, a differentiating circuit corresponding to each said electrical timing signal responsive to the leading edge of each of said electrical timing signals for producing a corresponding trigger signal pulse, an amplifier circuit having an output circuit corresponding to each said electrical timing signal for amplifying the said trigger signal pulses corresponding to the same said electrical timing signal, and a pulse transformer having a primary winding connected across said output circuit of each said amplifier and three secondary windings, one of which is connected across said gate-cathode electrodes of each the said extinguishing silicon controlled rectifier corresponding to the said inverter silicon controlled rectifier to be extinguished, the said inverter silicon controlled rectifier next to be triggered conductive and the said inverter silicon controlled rectifier last triggered conductive.

Claim 8

A three-phase inverter control circuit for producing gate-cathode trigger signals for the inverter and corresponding extinguishing silicon controlled rectifiers, each having gate, anode and cathode electrodes, of a three-phase inverter circuit and applying the trigger signals to the extinguishing and inverter silicon controlled rectifiers in the proper sequence to energize the phase windings of a three-phase alternating current motor from a direct current supply potential source comprising, a variable frequency oscillator, a shift register circuit responsive to the output signals of said variable frequency oscillator for producing a repeating series of six equally spaced electrical timing signals, a differentiating circuit corresponding to each said electrical timing signal responsive to the leading edge of each of said electrical timing signals for producing a corresponding trigger signal pulse, an amplifier circuit having an output circuit corresponding to each said electrical timing signal for amplifying the said trigger signal pulses corresponding to the same said electrical timing signal, and a pulse transformer having a primary winding connected across said output circuit of each said amplifier and three secondary windings, one of which is connected across said gate-cathode electrodes of each the said extinguishing silicon controlled rectifier corresponding to the said inverter silicon controlled rectifier to be extinguished, the said inverter silicon controlled rectifier next to be triggered conductive and the said inverter silicon controlled rectifier last triggered conductive.