Circuit device for driving an AC electric load
AssigneeSTMicroelectroncis S.r.I.
InventorsAntonino Milazzotto, Mario Di Guardo, Antonino Cucuccio, Francesco Di Marco
Life of this patent
Estimating the term…
Abstract
A circuit device is provided for driving an AC electric load, of the type inserted between a terminal of an AC power supply line and a terminal of the electric load to be driven and including a generator of PWM signals to be transferred to the load. This circuit is an AC/AC converter adapted to power supply the load from any level of the power supply line sinusoid and comprising first and second voltage driven switches, the first switch to power supply the load and the second switch to enable loop-back of the current. The switches always operate in a complementary manner, i.e., when the first switch is on, the other is off, and vice versa.
Claims20
A circuit device for driving an AC electric load, of a type inserted between a terminal of AC power supply line and a terminal of the electric load to be driven, the circuit device comprising:
- a generator of PWM signals to be transferred to the load;
- an AC/AC converter adapted to power supply the load from any level of the power supply line sinusoid;
- and
- first and second voltage driven switches, the first switch to power supply the load and the second switch to enable loop-back of current, said switches always operating in a complementary manner, where when the first switch is on, the second switch is off, and vice versa.
A circuit device for driving an AC electric load, of a type inserted between a first terminal of an AC power supply line and a terminal of the electric load to be driven and including a generator of PWM signals to be transferred to the load, the circuit device comprising:
- a first circuit block adapted to allow current from said load to flow unrestrictedly, said block being connected between a second terminal of said power supply source and a second circuit block;
- the second circuit block being connected to the first terminal of said power supply line and adapted to power said load upon said generator being turned on;
- a third circuit block adapted to transfer a signal from said generator into said first circuit block;
- and
- a fourth circuit block connected to said second circuit block and adapted to compensate for introduced delays.
A circuit device for driving an AC electric load, of the type inserted between a terminal of an AC power supply line and a terminal of the electric load to be driven and including a generator of PWM signals to be transferred to the load, the circuit device comprising first and second associated switches for driving respective terminals of the load, and a third switch voltage driven by a signal from said PWM generator, the third switch being used for driving the first and second switches through respective transformers.
An apparatus, comprising:
- a first circuit block having a first switch to allow loop-back load current to flow if the first switch is turned on for off times of a PWM control signal;
- a second circuit block coupled to the first circuit block and having a second switch that is complementary to the first switch of the first circuit block, the second switch being turned on to allow power to be supplied for on times of the PWM control signal;
- and
- a third circuit block coupled to the first circuit block to transfer the PWM control signal to the first circuit block to turn the first switch on or off.
A method, comprising:
- generating a PWM control signal;
- turning on a first switch and turning off a second switch during off times of the PWM control signal, to allow loop-back current to flow from a load;
- and
- turning off the first switch and turning on the second switch during on times of the PWM control signal, to allow current to flow into the load.
Dependencies are inferred from the claim text.