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.

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.

Abstract: Presented is a circuit device for driving an a.c. electric load, incorporating a rectifying bridge that has a first input connected to one terminal of the electric load and a second input connected to an outlet of an a.c. main supply. The rectifying bridge has output terminals connected to a power switch which is controlled by an electric signal. The circuit device has a circuit loop-back link connected in parallel to the electric load, and a second circuit loop-back link connected in parallel to the electric load. The first and second links are alternately activated by the positive and negative half-waves of the main supply when the switch is in its “off” state.

Abstract: The invention relates to a method and a device for recognizing and warning of the level of fullness of a waste container in a suction system driven by a motor and provided with an internal chamber kept under suction pressure and comprising the waste container. The method foresees a measurement of the difference of pressure between the internal chamber and the environment outside the vacuum cleaner and an elaboration of such measurement according to a set of rules in fuzzy logic for producing an electric warning signal corresponding to the filling level of the waste container.

Abstract: A process for the fuzzy control of switching power supplies which have at least one inductor and at least one switching device, and a device for performing this control, the particularity whereof resides in the fact that it comprises the following steps: measuring the value of the current on the inductor; measuring the value of the input voltage of the switching power supply; measuring an error generated between a reference voltage and an output voltage of the power supply; defining fuzzy membership functions for the value of the current on the inductor, for the input voltage value, and for the error; defining an output membership function for the value of the duty cycle of the power supply; defining multiple fuzzy inference rules to which the measured values and the membership functions are applied calculating the corresponding weight functions of the membership functions; defuzzifying the results obtained by means of the weight function calculation and the application of fuzzy rules so as to obtain a real v