KR100691766B1 - Method and apparatus for controlling actuator in ventilator for vehicle - Google Patents

Abstract

A method and a device for controlling an actuator of a vehicle air conditioner are provided to calculate rotation of a motor from a fine change of current generated by mechanical change of a stator and a brush of the motor, thereby controlling the actuator without any additional feedback signal generation part. A device for controlling an actuator of a vehicle air conditioner includes an actuator(40) mounted with a DC motor connected to a decelerating gear by lever, and a motor driver(20) for driving the motor in the actuator. A sensing resistor(50) is inserted between the actuator and the motor driver in serial to sense current flowing through the motor. A pulse generator(30) detects a signal representing a change of current ripples included in current signals of the motor, which are sensed at both ends of the sensing resistor, and generates a square wave pulse. A micro-controller(10) determines forward/backward rotation of the motor according to a target point of a door to control the actuator by sending a motor driving signal to the motor driver, and calculates an rpm of the motor by counting the square wave pulse to control the actuator according to the rpm for controlling the door to a desired position.

Description

Actuator control method and apparatus for a vehicle air conditioner {Method and apparatus for controlling actuator in ventilator for vehicle}

1 is a waveform diagram showing the current ripple of the motor generated when the commutator conversion of the actuator motor;

2 is a block diagram showing an actuator control apparatus for an air conditioner for a vehicle according to the present invention;

3 is a detailed block diagram illustrating a pulse generator of FIG. 2;

4 is a waveform diagram showing an operation of each configuration of FIG. 3;

5 is a flowchart illustrating a method for controlling an actuator of a vehicle air conditioner according to the present invention.

<Description of the symbols for the main parts of the drawings>

10: microcontroller 20: motor driver

30: pulse generator 40: actuator

50: sensing resistance

The present invention relates to an actuator for adjusting a door position of a vehicle air conditioner, and more particularly, to an actuator control method and apparatus for a vehicle air conditioner for controlling an actuator by detecting a rotation of a motor without a separate feedback device.

Actuator is used in the opening and closing drive of the door that is disposed inside the air conditioning system of the vehicle to control the flow of various air. That is, the actuator controls the position of the discharge direction door (Vent Door), the temperature control door (Air Mix Door), the indoor and outdoor air conditioner door (Intake Door) of the automotive air conditioner.

In such an automotive air conditioning system, the actuator is generally composed of a feedback signal generator for detecting the position of the DC motor connected to the reduction gear and the lever and the adjusting device therein. In particular, the feedback signal generator uses a voltage variable method using a potentiometer by a change in contact of carbon resistance printed on a PCB of a brush mechanically connected to an actuator reduction gear, and a photodiode and a phototransistor based on a rotation axis of a motor. There is a signaling method. However, this method has a disadvantage in that the unit cost is increased and the internal circuit is complicated because a separate feedback component is used in addition to the driving component. In addition, according to the adjustment range according to the design of the control device requires a separate design mechanically there is a disadvantage that can not be shared with each other.

Accordingly, an object of the present invention is to solve the above problems, to control the actuator without a separate feedback signal generator by calculating the rotation of the motor in pulses from the minute fluctuations in the current caused by the mechanical conversion of the commutator and brush of the motor To provide a way to do it.

Another object of the present invention to provide an apparatus for implementing the above-described actuator control method of the vehicle air conditioner.

Actuator control method of the vehicle air conditioner of the present invention for achieving the above object, in the door actuator control method of the vehicle air conditioner, (1) the current ripple change caused by the motor commutator conversion when the motor in the actuator rotates (2) converting the detected current ripple change of the motor into a DC square wave pulse form, (3) counting the converted DC square wave pulses, and calculating a rotation speed of the motor; and (4) controlling the actuator according to the calculated rotation speed to adjust the door to a desired position.

In another aspect of the present invention, there is provided an actuator control apparatus for a vehicle air conditioner, the apparatus for controlling a door actuator of a vehicle air conditioner, the actuator including only a DC motor connected to a reduction gear and a lever, and the motor in the actuator. Inserted in series between the motor driver for driving, the actuator and the motor driver, the sensing resistor for sensing the current flowing in the motor, and the current ripple change included in the current signal of the motor sensed across the sensing resistor A pulse generator for detecting and generating square wave pulses, and determining a forward / reverse rotation direction of the motor according to a target point of the door, and outputting a motor driving signal to the motor driver to control the actuator, and in the pulse generator The number of revolutions of the motor is calculated by pulse counting the generated square wave. And accordingly control the actuator to adjust the door to the desired position.

Hereinafter, exemplary embodiments of the present invention will be described in detail with reference to the accompanying drawings.

In general, a DC motor is composed of a stator made of a permanent magnet, a rotor formed by winding a coil, and a commutator for applying current to the rotor coil. In particular, the power supply terminal for supplying the commutator and the electric current is made using a brush. When power is supplied to the motor, current flows through the coil, which is the rotor, and the motor rotates, and the brush and the commutator alternate electrical contact with each other. At this time, the current ripple change generated by the mechanical conversion is generated as shown in FIG. 1 through a sensing resistance of several ohms inserted in series between the motor driver and the motor.

In the case of a motor currently used in an actuator, since three coil senses are included, three current ripple changes occur per motor revolution, and the present invention outputs two DC square waves when converting one commutator (= current ripple). Therefore, counting six square wave pulses for three current ripple changes detects one revolution of the motor. The present invention uses this to control the actuator so that the amount of rotation of the motor is appropriately adjusted so that the door is in the position desired by the user.

Figure 2 shows a block diagram of an actuator control device for a vehicle air conditioner according to the present invention. Actuator control device shown in Figure 2 is positive (+) to the actuator (40) equipped with a direct-current (DC) motor (M) that rotates forward and reverse according to the applied voltage, and the motor (M) of the actuator (40) And a hybrid motor driver 20 for driving in positive / reverse rotation by applying a negative / negative voltage. Here, the actuator 40 need only be equipped with a DC motor connected to the reduction gear and the lever without a separate feedback circuit configuration. The actuator control device of FIG. 2 also detects and responds to the sensing resistor 50 for sensing the current flowing in the motor M of the actuator 40 and the change in the sensed ripple (see waveform in FIG. 1). And a pulse generator 30 for generating a square wave pulse. The detailed configuration of the pulse generator 30 will be described later with reference to FIG. 3. Meanwhile, the actuator control apparatus of FIG. 2 drives the motor driver 20 according to a user operation, counts square wave pulses generated by the pulse generator 30, calculates the rotation speed of the motor M, and accordingly, the actuator ( And a microcontroller 10 for controlling 40.

3 is a detailed block diagram of the pulse generator 30 of FIG. 2. The pulse generator 30 shown in FIG. 3 blocks the direct current (DC) component from the signal sensed by the motor M of the actuator 40 and the AC differential amplifier 31 for detecting only a very small change in the current ripple. And an noise filter 32 for removing unnecessary noise components that cannot be removed from the AC differential amplifier 31. The pulse generator 30 of FIG. 3 further includes an absolute value converter 33 and an absolute value converter 33 which always correct the input of the signal to generate a positive output regardless of the polarity of the input signal. It consists of a square wave generator 34 for generating the rough final signal as a square wave of direct current having a stable period so that the microcontroller 10 can recognize.

An operation of the actuator control apparatus of the vehicle air conditioner according to the present invention having such a configuration will be described in detail with reference to FIGS. 4 and 5.

When the driver starts the vehicle by "on" the key after boarding the vehicle (step 501), each actuator 40 performs correction. This is to prevent the accumulation of pulse errors due to disturbance of the motor (M). To this end, the microcontroller 10 drives the motor driver 20 to rotate the motor M to the starting point of the actuator 40 door (step 502), and then the stored position, that is, the door position before turning off the start ( The actuator 40 is then controlled to the previous target point (step 503). The microcontroller 10 rotates the motor M in the actuator 40 by driving the motor driver 20 by the motor speed corresponding to the stored target point. As the motor M rotates, the door is positioned at the previous target point. At this time, the pulse generator 30 is converted into a square wave pulse that can be processed by the microcontroller 10, the motor (M) signal in the actuator 40 sensed by the sensing resistor (50). The microcontroller 10 counts the square wave pulses generated by the pulse generator 30 (step 504), and calculates the rotation speed of the motor M from the count value to determine whether the door is located at the previous target point (step 505). In this case, since six signals, that is, pulses are generated every time the motor rotates, the resolution is 60 °. When it is determined in step 505 that the previous target point is located, the microcontroller 10 stops driving the motor driver 20 to stop the rotation of the motor M in the actuator 40. If it is determined in step 505 that it is not located at the previous target point, the microcontroller 10 repeats the step from step 503.

When the calibration for each actuator 40 is completed through this process, the microcontroller 10 determines whether the user is operated (step 506). That is, when the driver operates the door actuator 40 by operating the switches on the vehicle air conditioning system, the microcontroller 10 calculates the number of pulses to the target point newly set by the user's operation (step 507), and then returns to the target point. The motor M starts to rotate (step 508). The microcontroller 10 determines the forward / reverse rotation direction of the motor M to drive the motor driver 20. The motor driver 20 is driven under the control of the microcontroller 10 to apply a predetermined positive / negative voltage to the motor M in the actuator 40. The motor M in the actuator 40 adjusts the door position by rotating in the forward / reverse direction according to a predetermined positive / negative voltage applied from the motor driver 20. At this time, the sensing resistor 50 connected in series with the motor M detects a current generated from the motor M. The current sensed by the sensing resistor 50 includes ripple as shown in FIG. 1. The pulse generator 30 receives a change in current ripple across the sensing resistor 50 and differentially amplifies only an AC component through the AC differential amplifier 31. That is, the AC differential amplifier 31 detects only the change in the current ripple as shown in (B) of FIG. 4 by performing differential bandwidth and differential filtering in which the DC component is cut off from the signal of the waveform of FIG. The pulse generator 30 filters the signal of the waveform (b) of FIG. 4 output from the AC differential amplifier 31 through the noise filter 32 to remove noise components. Here, the noise filter 32 is composed of a low level limiter and an integrator to remove unnecessary noise and signal components that cannot be removed from the AC differential amplifier 31. Then, regardless of the polarity of the input signal, the absolute value of the signal output from the noise filter 32 is always converted so that the input of the signal generates a positive (+) output of the waveform as shown in FIG. Make a signal. That is, the absolute value conversion unit 33 generates two pulses through the absolute value conversion for the current ripple change generated every time the motor M commutator is converted once (see waveform (c) of FIG. 4). The pulse generator 30 is a stable direct current having a constant period as shown in (d) of FIG. 4 through the square wave generator 34 so that the pulse shown in (c) of FIG. 4 can be recognized by the microcontroller 10. It converts into a square wave and applies it to the microcontroller 10.

The microcontroller 10 counts square wave pulses as shown in (d) of FIG. 4 generated in the pulse generator 30 (step 509). The microcontroller 10 checks whether the count value reaches the number of pulses up to the previously calculated target point (step 510). If the check result does not reach the target pulse number, the operation is repeated from step 508. If the count value is reached, the microcontroller 10 determines that the door is for the target point and stops the driving of the motor driver 20 so that the motor ( M) is stopped (step 511).

As described above, the actuator control method and apparatus of the vehicle air conditioner of the present invention, the actuator by calculating the rotational speed of the motor by using the minute fluctuation of the current generated by the contact of the commutator and the brush of the door actuator motor of the vehicle air conditioner The actuator can be controlled to a desired position without a separate feedback circuit therein. In addition, since only the DC motor needs to be mounted inside the actuator, the cost can be reduced and the controller can be shared with each other.

Claims (9)

In the door actuator control method of the vehicle air conditioner, (1) detecting a change in current ripple caused by motor commutator conversion when the motor in the actuator rotates; (2) converting the detected current ripple change of the motor into a DC square wave pulse form; (3) calculating the number of revolutions of the motor by counting the converted DC square wave pulses; And (4) controlling the actuator according to the calculated rotation speed, and adjusting the door to a desired position. 2. The actuator control according to claim 1, wherein the step (1) detects a current ripple change by detecting a current flowing in a motor in a rotating actuator at both ends of a sensing resistor inserted in series between the actuator and the motor driver. Way. 2. The actuator control method according to claim 1, wherein said step (2) converts a current ripple change generated by one-time conversion of a motor commutator into two DC square wave pulses. The method of claim 3, wherein step (2) (2a) differentially amplifying and band-filtering the input motor signal and detecting only a change in the current ripple from which the DC component is cut off; (2b) filtering the sensed current ripple change to remove noise components; (2c) generating a positive output by converting an absolute value of the signal from which the noise component is removed; And (2d) outputting the positive (+) output signal as a square wave of direct current. The method according to claim 1, wherein the step (4) determines whether the counted pulse number has reached the number of pulses up to a predetermined target point, and if the determination result is reached, the motor is stopped so as to reach the motor until it has reached. Actuator control method characterized in that the control to rotate. An apparatus for controlling a door actuator of a vehicle air conditioner, An actuator equipped only with a DC motor connected to the reduction gear and the lever; A motor driver for driving the motor in the actuator; A sensing resistor inserted in series between the actuator and the motor driver to sense a current flowing in the motor; A pulse generator for detecting a change in current ripple included in a current signal of the motor sensed at both ends of the sensing resistor and generating a square wave pulse; And Determine the forward / reverse rotation direction of the motor according to the target point of the door to control the actuator by sending a motor drive signal to the motor driver, and calculate the number of revolutions of the motor by pulse counting the square wave generated by the pulse generator And according to the actuator control device comprising a microcontroller for adjusting the door to the desired position. 7. The actuator control apparatus according to claim 6, wherein the current ripple change is caused by commutator conversion when the motor in the actuator rotates. The method of claim 6, wherein the pulse generator An AC differential amplifier for differentially amplifying and band-filtering the motor current signal sensed at both ends of the sensing resistor to detect only the current ripple change in which the DC component is cut off; A noise filter for filtering a current ripple change signal detected by the AC differential amplifier to remove noise components; An absolute value converter for generating a positive output irrespective of polarity by converting an absolute value signal through the noise filter; And And a square wave generator for generating a positive (+) output of the absolute value converter as a stable square wave pulse having a certain period so as to be recognized by the microcontroller. 9. The actuator control apparatus according to claim 8, wherein the noise filter is composed of a low level limiter and an integrator.

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