Abstract: Electronic device for controlling a synchronous motor with permanent-magnet rotor, comprising an alternating voltage current source at mains frequency connected in series with said synchronous motor (1), at least one static switch (2) connected in series with said synchronous motor (1), and an electronic circuit (3) that acts on said static switch (2). Said electronic circuit (3) determines the timing for the firing of the static switch (2) taking as reference the zero-crossing of the mains voltage (Vr) and applying a firing time (Td) starting from said reference, said firing time (Td) being obtained as a function of the position of the rotor (1A) of the motor (1) in the previous half-cycles.

Abstract: Electronic device for controlling a synchronous motor with permanent-magnet rotor, comprising an alternating voltage current source at mains frequency connected in series with said synchronous motor (1), at least one static switch (2) connected in series with said synchronous motor (1), and an electronic circuit (3) that acts on said static switch (2). Said electronic circuit (3) determines the timing for the firing of the static switch (2) taking as reference the zero-crossing of the mains voltage (Vr) and applying a firing time (Td) starting from said reference, said firing time (Td) being obtained as a function of the position of the rotor (1A) of the motor (1) in the previous half-cycles.

Abstract: On an electric cooker the sensor circuit (1) detects the presence of a pan (2) on each heater (F1-F4) and comprises a microcontroller (4) and a generator (6,7) that supply a high-frequency current (Ig) to a respective sensor loop (E1-E4) of each heater which generates a magnetic field, and two maximum and minimum reference signals (Vr0,Vr1) for all the heaters (F1-F4) obtained in the working temperature condition and a circuit (9-13) for measuring and evaluating the voltage (Vs) produced in each sensor loop, with a circuit part (11,11′) for demodulation into low frequency of the measuring and reference signals (Vs,Vr0,Vr1), and their differential amplification (Vm,Vrr).

Abstract: On an electric cooker the sensor circuit (1) detects the presence of a pan (2) on each heater (F1-F4) and comprises a microcontroller (4) and a generator (6,7) that supply a high-frequency current (Ig) to a respective sensor loop (E1-E4) of each heater which generates a magnetic field, and two maximum and minimum reference signals (Vr0,Vr1) for all the heaters (F1-F4) obtained in the working temperature condition and a circuit (9-13) for measuring and evaluating the voltage (Vs) produced in each sensor loop, with a circuit part (11,11′) for demodulation into low frequency of the measuring and reference signals (Vs,Vr0,Vr1), and their differential amplification (Vm,Vrr).