Device for controlling a switch for an electromechanical actuator and method for controlling such a device

Description

Technical Field

[0001] The present invention relates to a device and a method for controlling a switch formed by a controlled bidirectional semiconductor element.

[0002] It also relates to an electromechanical actuator comprising such a control device and implementing such a method. State of the Art

[0003] A device for controlling a switch formed by a controlled bidirectional semiconductor element for an electromechanical actuator comprises a load arranged in series with the switch, the load being adapted to be electrically powered by an alternating supply signal periodically passing through zero. The control device further comprises coupling elements, the coupling elements comprising the switch and being configured to couple the alternating supply signal to the load, elements for detecting a zero-crossing instant of the alternating supply voltage, the detection elements comprising an optocoupler configured to emit a rising edge or a falling edge on a logic input of a processing circuit when the alternating supply signal is substantially equal to zero,and control elements of the switch configured to emit control pulses on a control terminal of the switch following receipt of a control order from the electromechanical actuator, each pulse being adapted to place the switch in a closed state between two pulses and taking into account a control instant determined from a time of receipt of the rising edge or the falling edge of the optocoupler.,

[0004] It is known to control the switch in full-wave mode with control pulses emitted in synchronism with the instant of reception of the rising edge or the falling edge of the optocoupler corresponding substantially to the zero crossing of the AC power signal. When using an optocoupler as a source of information to control the switch, it is crucial that the optocoupler does not disperse too much because a time shift of the rising edge or the falling edge of the optocoupler causes a time shift of the control of the switch compared to the actual zero crossing instant of the AC power signal. Consequently, depending on whether the pulse is emitted too early or too late compared to the actual zero crossing instant, the switch may not remain in a closed state between two control pulses and thus cause a malfunction of the load or even a sudden shutdown of the load.

[0005] A disadvantage of using such a control device is that the optocoupler is subject in operation to a large variability of detection, this variability being able to be linked for example to the variability between series of components, to the temperature, or to the electrical or electromagnetic disturbances to which the optocoupler is subjected.

[0006] Document EP 0 720 268 A1 discloses a device for controlling the stopping of the operation of a motor in the event of detection of an overload relative to a threshold value. A triac controls the stopping of the motor on the basis of phase shift measuring means comprising zero crossing detection means.

[0007] Document FR 2 886 786 A1 describes a motor associated with a switch controlled by an electronic control unit to stop the motor, as well as a pair of diodes. The logic inputs of the control unit are connected to current sensors which provide information on the conduction state of the diodes.

[0008] It is therefore desirable to have a device for controlling a switch formed by a controlled bidirectional semiconductor element capable of compensating for the variability of the optocoupler. Summary of the invention

[0009] Embodiments relate to a device for controlling a switch formed by a controlled bidirectional semiconductor element for an electromechanical actuator, the electromagnetic actuator comprising a load arranged in series with the switch and adapted to be electrically powered by an alternating power supply signal periodically passing through zero, the control device further comprising: coupling elements, the coupling elements comprising the switch and being configured to couple the alternating supply signal to the load, elements for detecting a zero crossing instant of the alternating supply signal, the detection elements comprising at least one optocoupler, the optocoupler being configured to emit a rising edge or a falling edge on a logic input of a processing circuit when the alternating supply signal is substantially equal to zero, control elements of the switch, the control elements of the switch comprising the processing circuit and being configured to emit control pulses on a control terminal of the switch following receipt of a control command from the electromechanical actuator,each pulse being adapted to place the switch in a closed state between two pulses and taking into account a control instant determined from a first secondary instant of reception of the rising edge or the falling edge of the optocoupler, and elements for measuring the alternating supply signal, the measuring elements being configured to measure a value of the alternating supply signal.

[0010] The control device further comprises: first elements for determining a delay as a function of a first primary instant at which the processing circuit detects a rising edge or a falling edge on the logic input of the processing circuit, and of a second primary instant at which a value measured by the measuring elements reaches or exceeds a predetermined threshold value, and second elements for determining the control instant, the control instant being determined from the first secondary instant and the delay determined by the first determining elements.

[0011] According to embodiments, the instants may also be determined as a time interval from a reference, for example by a counter. In particular, the second primary instant may be determined as an interval between the first primary instant and the second primary instant, a counter may for example be started at the time of the first primary instant and stopped at the second primary instant.

[0012] According to one embodiment, the coupling elements further comprise a phase conductor and a neutral conductor, the phase and neutral conductors being electrically powered by the alternating power signal, and in that the load is an electric motor, the electric motor comprising a stator, the stator comprising two windings, the two windings each comprising a common end so as to electrically connect them together, the common end being electrically connected to the neutral conductor via the switch, each of the two windings comprising another end constituting respectively a first phase terminal and a second phase terminal, the first phase terminal being electrically connected to the second phase terminal via a phase shift capacitor,the phase conductor being selectively either electrically connected to the first phase terminal to control the rotational drive of the electric motor in a first direction, or electrically connected to the second phase terminal to control the rotational drive of the electric motor in a second direction, the second direction being opposite to the first direction.,

[0013] According to embodiments, the detection elements comprise third elements for determining a conduction state of a diode through which a current derived from the alternating supply signal flows, and in that the optocoupler is configured to detect the current flowing through the diode and emit a rising edge or a falling edge on a logic input of the processing circuit when the value of the current crosses a conduction threshold value of the diode at an instant when the alternating supply signal is substantially equal to zero.

[0014] According to embodiments, the control elements are configured to emit at least one series of pulses, each pulse of the series of pulses being emitted in synchronism with the control instant.

[0015] According to embodiments, the measuring elements comprise a resistive voltage divider bridge, the resistive voltage divider bridge being electrically connected on the one hand to the alternating supply signal and on the other hand to a measurement input of the processing circuit, the divider bridge being configured to adapt the alternating supply signal to the measurement input of the processing circuit.

[0016] According to embodiments, the first determining elements comprise a time counter integrated into the processing circuit, the time counter being initiated at the first primary instant, then stopped at the second primary instant.

[0017] According to embodiments, the second determining elements comprise at least one data item recorded in a memory of the processing circuit, the recorded data item comprising a value of a time period characteristic of the alternating power supply signal to pass from a zero value to the predetermined threshold value.

[0018] Embodiments may also relate to a method of controlling a switch for an electromechanical actuator, the electromechanical actuator comprising a control device according to that described previously, the method comprising at least: a first primary step of detecting a rising edge or a falling edge on the logic input of the processing circuit determining a first primary instant; a second primary step of detecting the reaching or exceeding of a threshold value by a value measured by the measuring elements determining a second primary instant; a third primary step of determining a delay value from the first primary instant and the second primary instant; a first secondary step of detecting a rising edge or a falling edge on the logic input of the processing circuit determining a first secondary instant; a second secondary step of determining a switch control instant from the first secondary instant and the delay value determined by the third primary step;and a third secondary step of controlling the switch from the control time determined by the second secondary step.;

[0019] According to embodiments, the third primary step comprises: a first primary sub-step of determining a third primary instant from the second primary instant, the third primary instant being calculated from a characteristic time period of the alternating supply signal to pass from a zero value to the threshold value; a second primary sub-step of determining the delay as a difference between the third primary instant and the first primary instant.

[0020] According to embodiments, the primary steps of the method are implemented when the switch is placed in an open state and / or when the electrical load is not electrically powered by the alternating power signal.

[0021] According to embodiments, the primary steps of the method are repeated an integer number n of times and in that the value of the control instant corresponds to an average value of the values ​​of the control instants determined at each repetition of the primary steps. Brief description of the figures

[0022] The present invention will be better understood with the aid of the following description with reference to the appended figures, in which identical reference signs correspond to structurally and / or functionally identical or similar elements. There figure 1 represents a general diagram of an actuator comprising a control device according to an embodiment of the invention. The figure 2 represents a detailed diagram of an actuator comprising a control device according to an embodiment of the invention. The figure 3represents a flowchart of a method according to one embodiment of the invention. The figure 4 represents a timing diagram of the output signal of an optocoupler of the control device, of the measurement of the alternating power supply signal of the control device carried out by measuring elements and of the control signal of a switch. Detailed description

[0023] The present invention finds its application in any type of electromechanical actuator such as a closing, concealment and / or solar protection device, for example a motorized blind, or a heating and / or ventilation and / or air conditioning device.

[0024] The electromechanical actuator ACT is configured to be electrically powered by an electrical network distributing an alternating power supply signal U0 periodically passing through zero, commonly called the "mains", the alternating power supply signal U0 being able to be, for example, of the 230 V - 50 Hz type. The electromechanical actuator ACT typically comprises a load adapted to be electrically powered by the alternating power supply signal U0, the load being arranged in series with a switch formed by a controlled bidirectional semiconductor element.

[0025] There figure 1 represents a control device 1 of a switch 2 formed by a controlled bidirectional semiconductor element, the control device 1 being able to be used in an electromechanical actuator ACT according to a first embodiment.

[0026] The control device 1 comprises a load 3 arranged in series with a switch 2. The load 3 is adapted to be electrically powered by the alternating power supply signal U0.

[0027] Switch 2 is formed by a controlled bidirectional semiconductor element such as a triac or two thyristors mounted head to tail.

[0028] The control device 1 further comprises coupling elements 5. The coupling elements 5 comprise the switch 2 and are configured to couple the alternating supply signal U0 to the load 3.

[0029] The control device 1 further comprises elements 6 for detecting a zero crossing instant of the alternating supply signal U0. The detection elements 6 comprise an optocoupler 61 (also called a photocoupler), the optocoupler 61 being configured to emit a rising edge or a falling edge on a logic input IN1 of a processing circuit 41 when the alternating supply signal U0 is substantially equal to zero.

[0030] The control device 1 further comprises control elements 4 of the switch 2, the control elements 4 comprising the processing circuit 41 and being configured to emit control pulses on a control terminal of the switch 2 following reception of a control order from the electromechanical actuator ACT, each pulse being adapted to place the switch 2 in a closed state between two pulses and taking into account a control instant tc determined from a first secondary instant ts1 of reception of the rising edge or the falling edge of the optocoupler.

[0031] Advantageously, the control elements 4 are configured to emit at least one series of control pulses for the switch 2, each pulse in the series of pulses being emitted in synchronism with the control instant tc.

[0032] Advantageously, the processing circuit 41 comprises a processor or a microcontroller, and at least one memory, the memory being able to be internal or external to the processor or microcontroller.

[0033] Advantageously, the control device 1 can also be controlled by a remote command reception circuit not shown, such as for example a radio command receiver.

[0034] The control device 1 further comprises measuring elements 7 for the alternating supply signal U0. The measuring elements 7 are configured to measure a value of the alternating supply signal U0.

[0035] Advantageously, the measuring elements 7 comprise a resistive voltage divider bridge, the resistive voltage divider bridge being electrically connected on the one hand to the alternating supply signal U0 and on the other hand to a measurement input IN0 of the processing circuit 41, the divider bridge being configured to adapt the alternating supply signal U0 to the measurement input IN0 of the processing circuit 41.

[0036] The control device 1 further comprises first elements 8 for determining a delay T1 as a function of a first primary instant tp1 at which the processing circuit 41 detects a rising edge or a falling edge on the logic input IN1, IN2 of the processing circuit 41, and of a second primary instant tp2 at which a value measured by the measuring elements 7 reaches or exceeds a predetermined threshold value VS.

[0037] Advantageously, the first determination elements 8 comprise a time counter integrated into the processing circuit 41, the time counter being initiated at the first primary instant tp1, then stopped at the second primary instant tp2.

[0038] The control device 1 further comprises second determining elements 9 for the control instant tc, the control instant tc being determined from the first secondary instant ts1 and the delay T1 determined by the first determining elements 8.

[0039] Advantageously, the second determining elements 9 comprise at least one item of data recorded in a memory of the processing circuit 41, the recorded item of data comprising a value of a period of time characteristic of the alternating supply signal U0 to pass from a zero value to the threshold value VS.

[0040] In a second embodiment of the invention, shown in figure 2, elements similar to those of the first embodiment bear the same references and function as explained above. In the following, we mainly describe what distinguishes this second embodiment from the first embodiment. In the following, when a reference sign is used in the description without being reproduced on the figure 2 or reproduced on the figure 2 without being mentioned in the description, it corresponds to the object bearing the same reference on the figure 1 .

[0041] We now describe with reference to the figure 2 , a control device 1 according to the second embodiment of the invention, in which the load 3 is a single-phase asynchronous type MOT electric motor with permanent capacitor.

[0042] Here, the coupling elements 5 further comprise a phase conductor ACP and a neutral conductor ACN. The phase conductors ACP and neutral conductor ACN are electrically supplied by the alternating supply signal U0.

[0043] Here, load 3 is an electric motor MOT, the electric motor MOT comprising a stator, the stator comprising two windings L1, L2.The two windings each comprise a common end N0 so as to electrically connect them together, the common end N0 being electrically connected to the neutral conductor ACN via the switch 2, each of the two windings L1, L2 comprising another end constituting respectively a first phase terminal P1 and a second phase terminal P2, the first phase terminal P1 being electrically connected to the second phase terminal P2 via a phase shift capacitor CM, the phase conductor ACP being selectively either electrically connected to the first phase terminal P1 to control the rotational drive of the electric motor MOT in a first direction DIR1, or electrically connected to the second phase terminal P2 to control the rotational drive of the electric motor MOT in a second direction DIR2, the second direction DIR2 being opposite to the first direction DIR1.

[0044] Here, the control device 1 further comprises a switch K. The switch K has at least two closed positions in which the phase conductor ACP is electrically connected to one or other of the two phase terminals P1, P2. The switch K may be manually controlled, or be controlled by a relay coil which can itself be controlled by a remote command reception circuit not shown, such as for example a radio command receiver. The switch K may, furthermore, have a third open position in addition to the two closed positions, in which the phase conductor ACP is electrically disconnected from the two phase terminals P1, P2. The switch K may optionally not be part of the electromechanical actuator ACT.

[0045] Here, depending on whether the switch K is presented either in the first closed position or in the second closed position, the phase conductor ACP is selectively electrically connected either to the first phase terminal P1 to control the rotational drive of the electric motor MOT in a first direction DIR1, or to the second phase terminal P2 to control the rotational drive of the electric motor MOT in a second direction DIR2, the second direction DIR2 being opposite to the first direction DIR1.

[0046] Advantageously, the control device 1 further comprises a resistive circuit CR, a first diode D1 and a second diode D2. The resistive circuit CR comprises a first resistor R1, a Zener diode Z1, and a capacitor C1. The first diode D1 and the second diode D2 are electrically connected together by an electrode of the same nature to one end A of the first resistor R1, the other electrode of each diode D1, D2 being respectively connected to the first phase terminal P1 and to the second phase terminal P2. The other end of the first resistor R1 constitutes a floating electrical ground GND of the control device 1. The floating electrical ground GND is electrically connected to the neutral conductor ACN via the Zener diode Z1 and the capacitor C1 electrically connected in parallel.The processing circuit 41 is electrically powered by an electrical voltage present at the terminals of the Zener diode Z1 and the capacitor C1, between the neutral conductor ACN electrically connected to a positive supply terminal VDD of the processing circuit 41, and the floating electrical ground GND of the control device 1 electrically connected to a negative supply terminal VSS of the processing circuit 41. The detail of the electrical power supply of the processing circuit 41, which comprises electrical voltage step-down and regulating components, is not shown in the figures.

[0047] Here, the first diode D1 and the second diode D2 are electrically connected together by their respective anode to one end A of the first resistor R1, the cathode of the first diode D1 is connected to the first phase terminal P1, and the cathode of the second diode D2 is electrically connected to the second phase terminal P2.

[0048] Advantageously, the detection elements 6 comprise a first optocoupler 61 and a second optocoupler 62, the first optocoupler 61 and the second optocoupler 62 being inserted into the control device 1 to detect a current flowing in the first diode D1 and in the second diode D2. An output of the first optocoupler 61 is electrically connected to a first logic input IN1 of the processing circuit 41, and an output of the second optocoupler 62 is electrically connected to a second logic input IN2 of the processing circuit 41. Each optocoupler 61, 62 switches the corresponding logic input IN1, IN2 to the high state when the corresponding diode conducts. The processing circuit 41 is thus able to identify the conduction or blocking state of the first diode D1 and the second diode D2.

[0049] The main advantage of this assembly is that, with the motor stopped, when the phase conductor ACP is electrically connected to the first phase terminal P1, the instant of start of conduction of the first diode D1, and therefore of appearance of a rising edge on the logic input IN1, corresponds to the instant at which the alternating supply signal U0 is substantially equal to zero when passing from a positive half-wave to a negative half-wave, in other words when the alternating supply signal U0 passes through zero when passing from a positive half-wave to a negative half-wave.The instant of end of conduction of the first diode D1, and therefore of appearance of a falling edge on the logic input IN1, corresponds to the instant at which the alternating supply signal U0 is substantially equal to zero when passing from a negative half-wave to a positive half-wave, in other words when the alternating supply signal U0 passes through zero when passing from a negative half-wave to a positive half-wave.

[0050] Similarly, when the phase conductor ACP is electrically connected to the second phase terminal P2, the instant of start of conduction of the second diode D2, and therefore of appearance of a rising edge on the logic input IN2, corresponds to the instant at which the alternating power supply signal U0 is substantially equal to zero when changing from a positive half-wave to a negative half-wave, in other words to the zero crossing of the alternating power supply signal U0 when changing from a positive half-wave to a negative half-wave. The instant of end of conduction of the second diode D2, and therefore of appearance of a falling edge on the logic input IN2, corresponds to the instant at which the alternating power supply signal U0 is substantially equal to zero when changing from a negative half-wave to a positive half-wave, in other words to the zero crossing of the alternating power supply signal U0 when changing from a negative half-wave to a positive half-wave.

[0051] Here, the measuring elements 7 comprise a third diode D3, a fourth diode D4, and a resistive voltage divider bridge consisting of at least a second resistor R2. The third diode D3 and the fourth diode D4 are electrically connected together by an electrode of the same nature to one end B of the second resistor R2, the other electrode of each diode D3, D4 being respectively connected to the first phase terminal P1 and to the second phase terminal P2. The other end of the second resistor R2 is electrically connected to the floating electrical ground GND of the control device 1. The end B of the second resistor R2 is electrically connected to a measurement input IN0 of the processing circuit 41. Thus, the processing circuit 41 is adapted to measure a value of the alternating power supply signal U0 by measuring an electrical voltage across the terminals of the second resistor R2.

[0052] Here, the third diode D3 and the fourth diode D4 are electrically connected together by their respective cathodes at the B end of the second resistor R2, the anode of the third diode D3 is connected to the first phase terminal P1, and the anode of the fourth diode D4 is electrically connected to the second phase terminal P2. Diodes D1 and D3 operate in opposition here, as do diodes D2 and D4.

[0053] There figure 3 illustrates steps of a method for controlling a switch 2, according to one embodiment. The control method is implemented by the processing circuit 41.

[0054] The steps of the ordering process are described below, in correspondence with the figure 4which represents a time diagram of the detection signal of the optocoupler 61, 62 detected by the detection elements 6, of the alternating power supply signal U0, of the control signal of the switch 2 generated by the control elements 4, and of the signal present at the terminals of the second resistor R2 measured by the measuring elements 7. This case makes it possible to illustrate the control method implemented for a control device according to one embodiment.

[0055] Advantageously, the primary steps of the method are implemented when the switch 2 is placed in an open state and / or when the electrical load 3 is not electrically powered by the alternating power supply signal U0.

[0056] The method comprises a first series of primary steps EP and a second series of secondary steps ES, the first series of steps being carried out upstream of the second series of steps. The delay T1 existing between a rising or falling edge of the optocoupler and the real zero sector is determined by the first series of steps so that it can be used in the second series of steps to control the switch 2 following the reception of a control command from the electromechanical actuator ACT.

[0057] The method comprises a primary step EP0 of determining a time period T2 characteristic of the alternating power supply signal U0 to pass from a zero value to the threshold value VS.

[0058] Advantageously, the time period T2 can be measured via the measuring elements 7, or predetermined in a memory of the processing circuit 41 when the value of the alternating supply signal U0 is considered fixed and stabilized.

[0059] Advantageously, the primary step EP0 is implemented when the processing circuit 41 determines that the signal received from the optocoupler 61, 62 is stabilized, for example when the interval between each rising edge or falling edge received on the logic input IN1, IN2 is determined to be constant for a predetermined duration corresponding to a predetermined number of rising or falling edges received on the logic input IN1, IN2.

[0060] The method further comprises a first primary step EP1 of detecting a rising edge or a falling edge on the logic input IN1, IN2 of the processing circuit 41 determining a first primary instant tp1.

[0061] The method further comprises a second primary step EP2 of detecting the reaching or exceeding of a threshold value VS by a value measured by the measuring elements 7 determining a second primary instant tp2 and / or a time period T3 corresponding to a time interval between the first primary instant tp1 and the second primary instant tp2, the second primary instant tp2 being located after the first primary instant tp1.

[0062] The method further comprises a third primary step EP3 of determining a value of a delay T1 from the first primary instant tp1 and the second primary instant tp2, or from the time period T2 and the time period T3, the time period corresponding to the delay T1 preceding the time period T2, the time period T3 running in parallel with the time period T1 and / or the time period T2.

[0063] Advantageously, the third primary step EP3 comprises at least a first primary sub-step EP32 for determining a third primary time tp3 from the second primary time tp2, the third primary time tp3 being calculated from the time period T2 characteristic of the alternating power supply signal U0 to pass from a zero value to the threshold value VS, and a second primary sub-step EP33 for determining the delay T1 as a difference between the third primary time tp3 and the first primary time tp1, or a difference between the time period T3 and the time period T2. The third primary time tp3 is located between the first primary time tp1 and the second primary time tp2, the second primary time tp2 being located after the first primary time tp1. The threshold value VS can for example be set at 100 mV to limit the risk of false measurement on the measurement input IN0 of the processing circuit 41.

[0064] The method further comprises a first secondary step ES1 of detecting a rising edge or a falling edge on the logic input of the processing circuit determining a first secondary instant ts1.

[0065] The method further comprises a second secondary step ES2 of determining a control time tc of the switch from the first secondary time ts1 and the delay value T1 determined by the third primary step EP3.

[0066] The method further comprises a third secondary step ES3 of controlling the switch 2 from the control time tc determined by the second secondary step ES2.

[0067] According to an example of realization illustrated by the figures 3 And 4 , the ACT electromechanical actuator is a motorized blind powered by an alternating power supply signal U0 of type 230 V - 50 Hz.

[0068] It is assumed as initial conditions that the control device 1 is energized during an initialization step of the electromechanical actuator ACT, for example when the electromechanical actuator ACT is energized. The load 3 of the electromechanical actuator ACT is initially stopped and not electrically powered, in other words immobile, and no control command is received by the electromechanical actuator ACT. As illustrated in figure 4 , each rising edge received on the logic input IN1 of the processing circuit 41 corresponds here to the zero crossing of the alternating supply signal U0 during the transition from a negative half-wave to a positive half-wave of the alternating supply signal U0.

[0069] The processing circuit 41 analyzes the signal from the optocoupler 61 over a time interval comprising four occurrences of rising edges of the optocoupler 61, and determines that the signal from the optocoupler 61 is stabilized.

[0070] The processing circuit 41 implements the primary step EP0 in which it detects for the first time the appearance of a rising edge on the logic input IN1 then measures the value of the alternating supply signal U0 on the measurement input IN0 until the measured value is zero, in other words equal to zero. The processing circuit 41 then triggers a time counter at the instant when the measured value is zero and continues to measure the value of the alternating supply signal U0 on the measurement input IN0 until the measured value reaches the threshold value VS, here 100 mV. Once the threshold value is reached, the processing circuit 41 stops the time counter then records the value of the measured time period T2 in a memory of the processing circuit 41.Here, the value of the recorded time period T2 corresponds to a time period between a first instant when the value of the alternating power supply signal U0 is zero and a second instant when the value of the alternating power supply signal U0 has reached the predetermined threshold value VS.

[0071] The processing circuit 41 then implements the first primary step EP1 in which it waits for the appearance of a new rising edge on the logic input IN1 until the detection of a rising edge on the logic input IN1, thus determining a first primary instant tp1.

[0072] Following detection of the rising edge, the processing circuit 41 implements the second primary step EP2 in which it triggers a time counter at the primary instant tp1 and measures the value of the alternating supply signal U0 on the measurement input IN0 until the threshold value VS is reached. Once the threshold value VS is reached at a second primary instant tp2, the processing circuit 41 stops the time counter and then reads the value of the time counter corresponding to a time period T3.

[0073] The processing circuit 41 then implements the third primary step EP3 in which it determines the value of the delay T1 by the relation T1 = T3 - T2, the value of the delay T1 corresponding to a time interval between the first primary instant tp1 corresponding to the appearance of a rising edge of the optocoupler, and a third primary instant tp3 corresponding to the instant following the first primary instant tp1 where the value of the alternating supply signal U0 is zero, in other words at the zero crossing of the alternating supply signal U0.

[0074] The processing circuit 41 then waits for receipt of a control order from the electromechanical actuator ACT, following which it implements a series of secondary steps in which it controls the switch 2 each time a rising edge appears on the logic input IN1, each control pulse from the switch 2 being emitted at a control instant tc with the delay T1 determined by the processing circuit 41.

[0075] It will be clear to those skilled in the art that the present invention is susceptible to various embodiment variants and application variants. In particular, the direction of mounting of the diodes D1 to D4 is susceptible to a multitude of variants having the effect of modifying the nature of the edge detected by the optocoupler. Similarly, the components forming the resistive circuit of the control device are susceptible to numerous variants.

Claims

1. A control device (1) for a switch (2) formed by a controlled bidirectional semiconductor element for an electromechanical actuator (ACT), the electromechanical actuator (ACT) including a load (3) disposed in series with the switch (2) and adapted to be electrically supplied by an alternating supply signal (U0) that periodically crosses zero, the control device (1) further comprising: - coupling elements (5), the coupling elements (5) comprising the switch (2) and being configured to couple the alternating supply signal (U0) to the load (3); - detection elements (6) for detecting a zero-crossing time of the alternating supply signal (U0), the detection elements (6) comprising at least one optocoupler (61, 62), the optocoupler (61, 62) being configured to emit a rising edge or a falling edge to a logic input (IN1, IN2) of a processing circuit (41) when the alternating supply signal (U0) is approximately equal to zero; - control elements (4) for controlling the switch (2), the control elements (4) for controlling the switch (2) comprising the processing circuit (41) and being configured to emit control pulses to a control terminal of the switch (2) following receipt of a control command of the electromechanical actuator (ACT), each pulse being adapted to set the switch (2) to a closed state between two pulses and taking into account a control time (tc) determined from a first secondary time (ts1) of receipt of the rising edge or of the falling edge from the optocoupler (61, 62), and - measurement elements (7) for measuring the alternating supply signal (U0), the measurement elements (7) being configured to measure a value of the alternating supply signal (U0), characterized in that the control device (1) further comprises: - first determination elements (8) for determining a delay (T1) according to a first primary time (tp1) at which the processing circuit (41) detects a rising edge or a falling edge on the logic input (IN1, IN2) of the processing circuit (41), and to a second primary time (tp2) at which a value measured by the measurement elements (7) reaches or exceeds a predetermined threshold value (VS), and - second determination elements (9) for determining the control time (tc), the control time (tc) being determined from the first secondary time (ts1) and the delay (T1) determined by the first determination elements (8).

2. The control device according to claim 1, characterized in that the coupling elements (5) further comprise a phase conductor (ACP) and a neutral conductor (ACN), the phase (ACP) and neutral (ACN) conductors being electrically supplied by the alternating supply signal (U0), and in that the load (3) is an electric motor (MOT), the electric motor (MOT) comprising a stator, the stator comprising two windings (L1, L2), the two windings (L1, L2) each comprising a common end (N0) so as to electrically link them together, the common end (N0) being electrically linked to the neutral conductor (ACN) through the switch (2), each of the two windings (L1, L2) comprising another end respectively constituting a first phase terminal (P1) and a second phase terminal (P2), the first phase terminal (P1) being electrically linked to the second phase terminal (P2) through a phase-shift capacitor (CM), the phase conductor (ACP) being selectively either electrically connected to the first phase terminal (P1) to control the rotation of the electric motor (MOT) in a first direction (DIR1), or electrically connected to the second phase terminal (P2) to control the rotation of the electric motor (MOT) in a second direction (DIR2), the second direction (DIR2) being opposite to the first direction (DIR1).

3. The control device (1) according to claim 1 or according to claim 2, characterized in that the detection elements (6) comprise third determination elements for determining a conduction state of a diode (D1, D2) through which a current derived from the alternating supply signal (U0) flows, and in that the optocoupler (61, 62) is configured to detect the current flowing through the diode (D1, D2) and to emit a rising edge or a falling edge on a logic input (IN1, IN2) of the processing circuit (41) when the value of the current crosses a conduction threshold value of the diode at a time when the alternating supply signal (U0) is substantially equal to zero.

4. The control device (1) according to any one of the preceding claims, characterized in that the control elements (4) are configured to emit at least one series of pulses, each pulse of the series of pulses being emitted in synchronism with the control time (tc).

5. The control device (1) according to any one of the preceding claims, characterized in that the measurement elements (7) comprise a resistive voltage divider bridge, the resistive voltage divider bridge being electrically linked, on the one hand, to the alternating supply signal (U0), and on the other hand, to a measurement input (INO) of the processing circuit (41), the divider bridge being configured to adapt the alternating supply signal (U0) to the measurement input (INO) of the processing circuit (41).

6. The control device (1) according to any one of the preceding claims, characterized in that the first determination elements (8) comprise a time counter integrated into the processing circuit (41), the time counter being started at the first primary time (tp1), and then stopped at the second primary time (tp2).

7. The control device (1) according to any one of the preceding claims, characterized in that the second determination elements (9) comprise at least one data recorded in a memory of the processing circuit (41), the stored data comprising a value of a time period (T2) characteristic of the alternating supply signal (U0) for transitioning from a zero value to the predetermined threshold value (VS).

8. A method for controlling a switch (2) for an electromechanical actuator (ACT), the electromechanical actuator (ACT) comprising a control device (1) according to any one of claims 1 to 7, characterized in that the method comprises at least: - a first primary step (EP1) of detecting a rising edge or a falling edge on the logic input (IN1, IN2) of the processing circuit (41), determining a first primary time (tp1); - a second primary step (EP2) of detecting the reaching or exceeding of a threshold value (VS) by a value measured by the measurement elements (7), determining a second primary time (tp2); - a third primary step (EP3) of determining a delay value (T1) from the first primary time (tp1) and the second primary time (tp2); - a first secondary step (ES1) of detecting a rising edge or a falling edge on the logic input (IN1, IN2) of the processing circuit (41), determining a first secondary time (tp2); - a second secondary step (ES2) of determining a control time (tc) of the switch (2) from the first secondary time (ts1) and the delay value (T1) determined in the third primary step (EP3); and - a third secondary step (ES3) of controlling the switch (2) from the control time (tc) determined in the second secondary step (ES2).

9. The control method according to claim 8, wherein the third primary step (EP3) comprises: - a first primary sub-step (EP31) of determining a third primary time (tp3) from the second primary time (tp2), the third primary time (tp3) being calculated from a time period (T2) characteristic of the alternating supply signal (U0) for transitioning from a zero value to the threshold value (VS); - a second primary sub-step (EP32) of determining the delay (T1) as a difference between the third primary time (tp3) and the first primary time (tp1).

10. The control method according to claim 8, characterized in that the primary steps of the method are implemented when the switch (2) is set in an open state and / or when the electrical load (3) is not electrically supplied by the alternating supply signal (U0).

11. The control method according to any one of claims 7 to 10, characterized in that the primary steps of the method are repeated an integer number n of times and in that the value of the control time (tc) corresponds to an average value of the values of the control times determined at each repetition of the primary steps.