JP2011113781A - Electronic control device - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To prevent circuit-break of a relay from occurring due to a falling of the voltage applied to a relay coil to below the open-circuit voltage when causing a power source voltage drop at the time of a power-on of driving power source of another actuator or an instantaneous power failure. <P>SOLUTION: In the electronic control device, when supplying a driving voltage with an actuator driving circuit 15 in a state that the voltage applied to both the ends of a coil of alternating current relay is equal to or higher than the open-circuit voltage and lower than the operation voltage, a control device 3 outputs a relay driving signal 5 the prescribed time period before the control device 3 outputs an actuator driving circuit power source energizing signal 11. <P>COPYRIGHT: (C)2011,JPO&INPIT

Description

  The present invention relates to an electronic control device for driving an AC relay and an actuator, and more particularly to a control method for an electronic control device for an air conditioner indoor unit having an AC relay that supplies power to an air conditioner outdoor unit.

  In electrical appliances and the like, as one of the methods for driving each electric / electronic circuit, a relay driving circuit is used, and the relay driving circuit is used to set the relay to an excited state or a non-excited state. Electronic circuits are often turned on / off.

  Conventionally, in order to drive the relay with low power consumption and temperature rise, the relay voltage is applied to both ends of the relay coil at the start of driving the relay, and the voltage across the relay coil is opened after a certain period of time. A method is adopted in which the voltage is kept at a voltage that is higher than the voltage and lower than the moving voltage (for example, see Patent Document 1).

  FIG. 3 is a circuit diagram showing an electronic control device including a relay drive circuit described in Patent Document 1. FIG. 4 shows a power supply timing chart to the relay and actuator drive circuit mounted on the electronic control unit. As shown in FIG. 3, an AC relay 2 for opening and closing an AC power supply includes a DC drive power supply 1 provided to drive the AC relay and actuator drive circuit, and the AC relay and actuator drive circuit. The controller 3 outputs a signal for controlling the power supply of the relay, the relay drive signal 5 output from the controller 3, the coil current control resistor 3, and the relay drive current switching element 6 are relayed to both ends of the coil of the AC relay 2. Apply or block a voltage (12V) higher than the moving voltage (9V). The relay holding signal 7 output from the controller 3, the coil holding current control resistor 9 and the coil holding current switching element 8 are applied to both ends of the coil of the AC relay 2 with a voltage (7 V) that is greater than or equal to the relay open voltage (6 V) and less than the sensing voltage. ) Is applied or cut off.

  In addition, an actuator drive circuit power supply smoothing capacitor 13 provided to stabilize the voltage ripple is connected to the drive power supply of the actuator drive circuit 15, and the actuator drive circuit power supply energized from the controller 3 is connected. By supplying ON / OFF signals of the signal 11 to the actuator drive circuit power supply energization switching element 14 via the buffer 12, drive power is supplied to and cut off from the actuator drive circuit.

  As shown in FIG. 4, when driving the AC relay 2 for opening and closing the AC power supply, a relay drive signal 5 is output from the controller 3, and a relay moving voltage (9 V) is applied across the coil of the AC relay 2. After supplying the above voltage (12V) and driving the relay, the relay holding signal 7 output from the controller 3 is output. At the both ends of the coil, the relay open voltage (6V) is at a voltage (7V) which is greater than the open circuit voltage and less than the moving voltage. By holding, the relay power consumption in the holding state is reduced.

JP 2004-72806 A

However, in the conventional configuration, when the voltage across the relay coil is held, the actuator drive circuit power supply starts energization, and a voltage drop of about 2 V or more occurs in the DC drive power supply due to the charging current to the power supply smoothing capacitor. However, the voltage across the coil and the open-circuit voltage (6 V) are below the relay, causing the relay to be interrupted.

  SUMMARY OF THE INVENTION The present invention solves the above-described conventional problems, and an object thereof is to provide an electronic control device in which a relay is not cut off even when a voltage drop occurs due to an instantaneous power failure or the like.

  In order to solve the conventional problem, an electronic control device of the present invention includes an AC relay for opening and closing an AC power supply, a DC drive power supply provided for driving the AC relay and the actuator drive circuit, A controller that outputs a signal for controlling power supply to the AC relay and the actuator drive circuit, and a voltage that is equal to or higher than the relay moving voltage at both ends of the AC relay coil by ON / OFF of the relay drive signal output from the controller A coil current control resistor and a relay drive current switching element for supplying and shutting off, and ON / OFF of a relay holding signal output from the controller, a voltage that is greater than or equal to the relay open voltage and less than the sensing voltage is applied to both ends of the AC relay coil. A coil holding current control resistor and a coil holding current switching element for supplying and shutting off, and the actuator The actuator drive circuit power supply smoothing capacitor provided to stabilize the drive power supply voltage ripple of the data drive circuit and the actuator drive circuit power supply energization signal output from the controller is turned on and off to drive the actuator drive circuit Actuator drive circuit for supplying and shutting off power supply power supply switching element and buffer.

  When the driving power is supplied to the actuator driving circuit when the actuator driving circuit power supply energization signal is OFF and the voltage applied to both ends of the coil of the AC relay is not less than the open voltage and less than the moving voltage, the actuator driving circuit power The energization signal and the relay drive signal are turned ON simultaneously.

  As a result, when the actuator drive circuit power supply starts energization and the power supply smoothing capacitor starts to be charged, the voltage applied to both ends of the coil of the AC relay becomes equal to or higher than the moving voltage.

  In the electronic control device of the present invention, even if the actuator drive circuit power supply starts energization and the voltage applied to the coil drive voltage drops due to the charging current to the power supply smoothing capacitor, the voltage applied to both ends of the coil does not drop below the open circuit voltage. The relay can be prevented from being cut off.

1 is a block diagram of an electronic control device according to Embodiment 1 of the present invention. Timing chart of relay drive and holding voltage in Embodiment 1 of the present invention Block diagram of electronic control device described in Patent Document 1 Patent Document 1: Relay driving and holding voltage timing chart

A first aspect of the present invention is an AC relay for opening and closing an AC power source, a DC driving power source provided for driving the AC relay and the actuator driving circuit, and power supply to the AC relay and the actuator driving circuit. A controller for outputting a signal for controlling the relay, and a coil current control resistor for supplying and shutting off a voltage greater than or equal to the relay moving voltage to both ends of the AC relay coil by turning ON / OFF the relay drive signal output from the controller, and Current holding resistance at coil holding for supplying / cutting off a voltage that is greater than or equal to the relay open voltage and less than the sensing voltage to both ends of the AC relay coil by ON / OFF of a relay holding current switching element and a relay holding signal output from the controller In addition, the coil holding current switching element and the drive voltage ripple of the actuator drive circuit are stabilized. Actuator drive circuit power supply for supplying and shutting off the drive power to the actuator drive circuit by turning ON / OFF the actuator drive circuit power supply smoothing capacitor and the actuator drive circuit power supply energization signal output from the controller In the electronic control device having an energization switching element and a buffer, the actuator drive circuit power supply energization signal is OFF and the voltage applied to both ends of the coil of the AC relay is not less than the open voltage and less than the moving voltage. When supplying the drive power, the actuator drive circuit power supply starts energization by simultaneously turning on the actuator drive circuit power supply energization signal and the relay drive signal, and when the power smoothing capacitor starts charging, the AC relay The voltage applied to both ends of the coil exceeds the moving voltage, the actuator drive circuit power supply starts energizing, and even if a drop occurs in the voltage applied to both ends of the coil due to the voltage drop of the DC drive power supply due to the charging current to the power supply smoothing capacitor Since the voltage does not fall below the voltage, the relay can be prevented from being cut off.

  In a second aspect of the invention, in particular, in the electronic control unit of the first aspect of the invention, the actuator drive circuit power supply energization signal is OFF and the voltage applied to both ends of the coil of the AC relay is greater than the open circuit voltage and less than the moving voltage. When supplying drive power to the actuator drive circuit, the relay drive signal is changed to the ON state, and the actuator drive circuit power supply energization signal is turned ON after a lapse of a certain time, so that the voltage applied to both ends of the coil becomes equal to or higher than the moving voltage. Even when a delay time occurs until the actuator drive circuit power supply starts energizing and a voltage drop of the DC drive power supply occurs due to the charging current to the power supply smoothing capacitor, it is possible to ensure that the voltage applied to both ends of the coil is equal to or higher than the moving voltage. Even if a drop occurs in the voltage applied to both ends of the coil, it becomes lower than the open circuit voltage. Since bets is no, it is possible to avoid that the relay is interrupted.

  According to a third invention, in particular, in the electronic control device of the first invention, there are two or more actuator drive circuits, at least one of the power supply energization signals of the actuator drive circuit is in an OFF state, and the AC relay When supplying drive power to the actuator drive circuit in the OFF state when the voltage applied to both ends of the coil is greater than the open circuit voltage and less than the sensing voltage, turn on the actuator drive circuit power supply energization signal and the relay drive signal simultaneously. Thus, when any one of the actuator drive circuit power supplies starts energization and charging of the power supply smoothing capacitor begins, the voltage applied to both ends of the coil of the AC relay is equal to or higher than the moving voltage, and the actuator drive circuit power supply is energized. DC drive power supply by starting and charging current to the smoothing capacitor Even if a drop occurs in the voltage applied to both ends of the coil due to the voltage drop, the relay does not fall below the open circuit voltage, so that the relay can be prevented from being cut off.

  According to a fourth aspect of the invention, in particular, in the electronic control device of the first aspect of the present invention, there are two or more actuator drive circuits, at least one of the power supply energization signals of the actuator drive circuit is in an OFF state, and the AC relay When supplying drive power to the actuator drive circuit in the OFF state when the voltage applied to both ends of the coil is greater than the open circuit voltage and less than the sensing voltage, the relay drive signal is changed to the ON state and the actuator is driven after a lapse of a certain time. Even if a delay time occurs until the voltage applied to both ends of the coil exceeds the moving voltage by turning on the circuit power supply energization signal, one of the actuator drive circuit power supplies starts energization and the charging current to the power supply smoothing capacitor Impress the voltage applied to both ends of the coil when a DC drive power supply voltage drop occurs due to Since the voltage can be secured above the voltage, even if a drop occurs in the voltage applied to both ends of the coil, the voltage does not fall below the open-circuit voltage, so that the relay can be prevented from being cut off.

  According to a fifth aspect of the present invention, in particular, in the electronic control device according to the first to fourth aspects of the invention, when the control device is an electronic control device for an air conditioner indoor unit, the AC relay is an electronic control for an air conditioner outdoor unit. It is a relay for supplying AC power to the device, and by turning on the AC relay only when operating the outdoor unit, it is possible to reduce power consumption when the outdoor unit is not operated and increase efficiency. Become.

  Hereinafter, embodiments of the present invention will be described with reference to the drawings. Note that the present invention is not limited to the embodiments.

(Embodiment 1)
FIG. 1 is a circuit diagram showing an electronic control device including a relay drive circuit. FIG. 2 shows a timing chart for supplying power to the relay and actuator drive circuit mounted on the electronic control unit.

  As shown in FIG. 1, an AC relay 2 for opening and closing an AC power supply includes a DC drive power supply 1 provided to drive the AC relay 2 and the actuator drive circuit 15, the AC relay 2 and the actuator. A controller 3 that outputs a signal for controlling power supply to the drive circuit 15, a relay drive signal 5 that is output from the controller 3, a coil current control resistor 3, and a relay drive current switching element 6, A voltage (12 V) equal to or higher than the relay moving voltage (9 V) is applied to or cut off from both ends of the coil. The relay holding signal 7 output from the controller 3, the coil holding current control resistor 9 and the coil holding current switching element 8 are applied to both ends of the coil of the AC relay 2 with a voltage (7 V) that is greater than or equal to the relay open voltage (6 V) and less than the sensing voltage. ) Is applied or cut off.

  In addition, an actuator drive circuit power supply smoothing capacitor 13 provided to stabilize the voltage ripple is connected to the drive power supply of the actuator drive circuit 15, and the actuator drive circuit power supply energized from the controller 3 is connected. By supplying ON / OFF signals of the signal 11 to the actuator drive circuit power supply energization switching element 14 via the buffer 12, drive power is supplied to and cut off from the actuator drive circuit.

  As shown in FIG. 2, when driving the AC relay 2 for opening and closing the AC power supply, a relay drive signal 5 is output from the controller 3, and a relay moving voltage (9 V) is applied across the coil of the AC relay 2. After supplying the above voltage (12V) and driving the relay, the relay holding signal 7 output from the controller 3 is output. At the both ends of the coil, the relay open voltage (6V) is at a voltage (7V) which is greater than the open circuit voltage and less than the moving voltage. By holding, the relay power consumption in the holding state is reduced.

  When the actuator drive circuit 15 starts to operate, first, an actuator drive circuit power supply energization signal 11 is output from the controller 3 to start charging the power supply smoothing capacitor. First, the relay drive signal 5 is output from the controller 3 500 ms before the actuator drive circuit power supply energization signal 11 is output from the controller 3, and the voltage applied to both ends of the coil of the AC relay is 12V. As a result, a voltage drop of about 2V occurs in the DC drive power supply 1 due to the charging current to the power supply smoothing capacitor 13, and even if a drop occurs in the voltage applied to both ends of the coil, it does not fall below the open circuit voltage of 6V. It is possible to avoid that 2 is blocked.

As described above, the electronic control device according to the present invention is reliable in that the relay drive voltage due to the operation of other actuators or power supply voltage fluctuations does not block the relay against the drop while reducing the power consumption of the relay. Since improvement can be aimed at, it can apply to the household appliances which are controlling the power supply of the heater which operate | moves with AC power supplies, such as an electric water heater, by an AC relay.

DESCRIPTION OF SYMBOLS 1 DC drive power supply 2 AC relay 3 Coil current limiting resistance 4 Control part 5 Relay drive signal line 6 Coil drive current switching element 7 Relay holding signal line 8 Coil holding current switching element 9 Coil holding current limiting resistance 10 Inrush current limiting resistance 11 Actuator drive circuit power supply energization signal line 12 Buffer 13 Actuator drive circuit power supply smoothing capacitor 14 Actuator drive circuit power supply energization switch 15 Actuator drive circuit

Claims (5)

An AC relay for opening and closing an AC power supply, a DC drive power supply provided for driving the AC relay and the actuator drive circuit, and a signal for controlling power supply to the AC relay and the actuator drive circuit are output. And a coil current control resistor and a relay drive current switching element for supplying and shutting off a voltage exceeding the relay moving voltage across the AC relay coil by turning on and off the relay drive signal output from the controller A coil holding current control resistor and a coil holding current switching element for supplying and shutting off a voltage that is greater than or equal to the relay open voltage and less than the sensing voltage to both ends of the AC relay coil by turning ON / OFF the relay holding signal output from the controller And to stabilize the drive power supply voltage ripple of the actuator drive circuit. Actuator drive circuit power supply smoothing capacitor and actuator drive circuit power supply energization switching element for supplying and shutting off the drive power to the actuator drive circuit by ON / OFF of the actuator drive circuit power supply energization signal output from the controller, and In the electronic control unit having a buffer, the driving power is supplied to the actuator driving circuit when the actuator driving circuit power supply energization signal is OFF and the voltage applied to both ends of the coil of the AC relay is not less than the open voltage and less than the moving voltage. In the electronic control device, the actuator drive circuit power supply energization signal and the relay drive signal are simultaneously turned on. When supplying drive power to the actuator drive circuit in a state where the actuator drive circuit power supply energization signal is OFF and the voltage applied to both ends of the coil of the AC relay is greater than the open circuit voltage and less than the moving voltage, the relay drive signal is 2. The electronic control device according to claim 1, wherein the actuator drive circuit power supply energization signal is turned on after a predetermined time has elapsed after being changed to the ON state. Two or more actuator drive circuits exist, at least one of the power supply energization signals of the actuator drive circuit is in an OFF state, and the voltage applied to both ends of the coil of the AC relay is in a state of an open voltage or more and less than a moving voltage 2. The electronic control device according to claim 1, wherein when the drive power is supplied to the actuator drive circuit in the OFF state, the actuator drive circuit power supply energization signal and the relay drive signal are simultaneously turned on. Two or more actuator drive circuits exist, at least one of the power supply energization signals of the actuator drive circuit is in an OFF state, and the voltage applied to both ends of the coil of the AC relay is in a state of an open voltage or more and less than a moving voltage 2. The electronic device according to claim 1, wherein when driving power is supplied to the actuator driving circuit in an OFF state, the relay driving signal is changed to an ON state, and the actuator driving circuit power supply energization signal is turned on after a predetermined time has elapsed. Control device. The control device is an electronic controller for an air conditioner indoor unit, the AC relay is a relay for supplying AC power to the electronic controller for an air conditioner outdoor unit, and the AC relay is only used when operating the outdoor unit. The electronic control device according to claim 1, wherein the electronic control device is turned on.

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