Blanking interval voltage deviation compensator for inverters and converters

A method for compensating a voltage deviation in the output voltage of a pulse-width-modulation (PWM) converter, said converter including a bridge having three legs, said PWM using a carrier signal, a magnitude of the carrier signal having a positive peak and a negative peak, comprising the steps of:

• providing a plurality of reference current signals, each displaced by a phase angle from an adjacent reference current, one reference current associated with each leg;
• providing a plurality of first augmented reference voltage signals to a pulse-width modulation circuit, each first augmented reference voltage being associated with a single one of said reference current signals;
• calculating a blanking interval compensation voltage signal in response to a DC buss voltage of said converter a blanking interval, and a period of said carrier signal;
• adding the blanking interval voltage compensation signals to said first augmented reference voltage signal when said converter is not saturated and said step of adding will not cause said converter to saturate, thereby providing a second augmented reference signal.

A device for compensating a voltage deviation in a output voltage of a pulse-width-modulation (PWM) inverter, said inverter including a bridge having three legs, said PWM using a carrier signal, a magnitude of the carrier signal having a positive peak and a negative peak, comprising:

• means for providing a plurality of reference current signals, each displaced by a phase angle from a adjacent reference current, one reference current associated with each leg;
• means for providing a plurality of first augmented reference voltage signals to a pulse-width modulation circuit, each first augmented reference voltage being associated with a single one of said reference current signals;
• means for calculating a blanking interval compensation voltage signal in response to a DC buss voltage of said inverter, a blanking interval, and a period of said carrier signal;
• means for providing a product of said blanking interval voltage deviation compensation signal and a polarity of the magnitude of one of said reference currents;
• means for summing said product with said one of said first augmented reference voltage signal and providing a sum;
• means for providing a second augmented reference voltage signal, including
• first means for comparing said positive peak to said first augmented reference voltage signal and providing said second augmented reference voltage signal at a value equal to the positive peak when said first augmented reference voltage signal is greater than said positive peak;
• second means for comparing said negative peak to said first augmented reference voltage signal and providing said second augmented reference voltage signal at a value equal to the negative peak when said first augmented reference voltage signal is less than said negative peak;
• third means for comparing said sum with said positive peak and providing said second augmented reference voltage signal at a value equal to a magnitude of said first augmented reference voltage signal when said positive peak is less than said sum;
• fourth means for comparing said sum with said negative peak and providing said second augmented reference voltage signal at a value equal to the magnitude of said first augmented reference voltage signal when said negative peak is less than said sum;
• means for providing said second augmented reference voltage signal at a value equal to said sum if said sum is neither greater than nor less than said positive and negative peaks.

A device for compensating a voltage deviation in the output voltage of a pulse-width-modulation (PWM) converter, said converter including a bridge having three legs, said PWM using a carrier signal, the magnitude of the carrier signal having a positive peak and a negative peak, comprising:

• means for providing a plurality of reference current signals, each displaced by a phase angle from the adjacent reference current, one reference current associated with each leg;
• means for providing a plurality of first augmented reference voltage signals to a pulse-width modulation circuit, each first augmented reference voltage being associated with a single one of said reference current signals;
• means for calculating a blanking interval compensation voltage signal in response to a DC buss voltage of said converter, a blanking interval, and a period of said carrier signal;
• means for providing a product of said blanking interval voltage deviation compensation signal and a polarity of the magnitude of one of said reference currents;
• means for summing said product with said first augmented reference voltage signal and providing a sum;
• means for providing a second augmented reference voltage signal, including
• first means for comparing said positive peak to said first augmented reference voltage signal and providing said second augmented reference voltage signal at a value equal to the positive peak when said first augmented reference voltage signal is greater than said positive peak;
• second means for comparing said negative peak to said first augmented reference voltage signal and providing said second augmented reference voltage signal at a value equal to the negative peak when said first augmented reference voltage signal is less than said negative peak;
• third means for comparing said sum with said positive peak and providing said second augmented reference voltage signal at a value equal to a magnitude of said first augmented reference voltage signal when said positive peak is less than said sum;
• fourth means for comparing said sum with said negative peak and providing said second augmented reference voltage signal at a value equal to the magnitude of said first augmented reference voltage signal when said negative peak is less than said sum;
• means for providing said second augmented reference voltage signal at a value equal to said sum if said sum is neither greater than nor less than said positive and negative peaks.