JP2005176525A - Fan motor control device - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To enable a control means that wholly controls a fan motor control device properly to detect the operation abnormal state of a fan motor, and to conduct proper operation control against the detected abnormality. <P>SOLUTION: When an applied voltage to the fan motor 4 detected by a voltage detection means 5 reaches a second voltage value, a controlling microcomputer 2 that outputs a PWM signal as a control signal to the fan motor control means 3 that conducts power-feed control to the fan motor 4, conducts control for lowering a duty ratio of the PWM signal, to lower a power-feed voltage to the fan motor 4 from the fan motor control means 3, and to cause the fan motor 4 to be driven at a proper voltage. When the applied voltage to the fan motor 4 is abruptly increased and reaches a first voltage value before the reduction control of the PWM signal by the controlling microcomputer 2 is conducted, a voltage restriction means 6 quickly operates in terms of hardware, and restricts an output voltage from the fan motor control means 3 to the first voltage value or lower. <P>COPYRIGHT: (C)2005,JPO&NCIPI

Description

  The present invention relates to a fan motor control device that performs drive control of a fan motor used for ventilation of a combustion device, and more particularly to a technique for accurately detecting an abnormality and improving the reliability of a protection operation when the fan motor is abnormal.

  For example, in a DC fan motor control method, a fan motor control instruction signal is transmitted from a microcomputer to a fan motor control circuit, and a voltage corresponding to the instruction signal is applied to the fan motor. At that time, the current flowing through the fan motor is configured such that the signal converted into voltage by the current detection unit is fed back to the fan motor control circuit in hardware, and the current that matches the control signal from the microcomputer flows. (For example, refer to Patent Document 1).

JP-A-8-266080

  In addition, as a method of detecting an abnormality of the fan motor, a method of monitoring the rotational speed of the fan motor with a microcomputer and determining that this is out of the predetermined appropriate rotational speed range is a general technique. When it is determined that the fan motor is abnormal, the fan motor operation is stopped under the control of the microcomputer, and this abnormality is reported.

  As described above, the fan motor current actually flowing to the fan motor is merely fed back to the fan motor control circuit in hardware, and the microcomputer indicates that the fan motor current increases due to the abnormality of the fan motor. Is unrecognizable. For this reason, if the current to the fan motor increases due to load fluctuations, the applied voltage to the fan motor is reduced by the operation of the fan motor control circuit based on the current feedback even if there is no danger due to this current increase. If the rotational speed of the motor is outside the range of the appropriate rotational speed, the microcomputer may determine that this is a fan motor abnormality and may stop the fan motor operation.

  The problem of the present invention is that the control means for comprehensively controlling the fan motor control device accurately detects the abnormal operation state of the fan motor and enables proper operation control for the detected abnormal state. It is to improve the reliability as a device.

  In order to solve the above-mentioned problems, the invention according to claim 1 is a control means for comprehensively controlling driving / stopping of the fan motor, and a voltage based on a control signal from the control means is applied to the fan motor. And a fan motor control means for controlling the applied voltage to the fan motor so that the fed back applied voltage matches the voltage based on the control signal. The voltage detection means for detecting the voltage to be applied, and the hardware applied when the voltage applied to the fan motor reaches a first voltage value that is a predetermined limit voltage, and the voltage applied to the fan motor is set to the first voltage. Voltage limiting means for limiting the voltage value to be equal to or lower than the voltage value, and the control means for receiving the voltage value detected by the voltage detecting means is an appropriate range of voltage applied to the fan motor. Non-volatile storage means for storing a predetermined second voltage value as a value lower than the first voltage value, and the voltage value detected by the voltage detection means is the non-volatile An abnormality determination unit that determines an abnormal state that has reached the second voltage value stored in the storage unit, and a fan motor control unit that reduces the applied voltage to the fan motor based on the abnormality determination by the abnormality determination unit. And an abnormal operation control means for changing the control signal.

  According to a second aspect of the present invention, in the fan motor control device according to the first aspect of the present invention, before the fan motor voltage gradually rises and the voltage limiting means operates, the control means is a voltage detection means. When it is determined by the signal from the abnormal state that the second voltage value has been exceeded, the control means changes the control signal to the fan motor control means so that the voltage applied to the fan motor is less than the second voltage. It is characterized by that.

  According to a third aspect of the present invention, in the fan motor control device according to the first or second aspect of the invention, the control means detects that the fan motor voltage exceeds the second voltage value based on the detection information of the voltage detection means. The voltage limiting means functions at a response speed sufficiently faster than the time required to determine the state and change the control signal to the fan motor control means, and the control means sets the second voltage value to the second voltage value. In addition, non-volatile storage means for storing the first voltage value, and a restriction state determination for determining a restriction state in which the voltage value detected by the voltage detection means has reached the first voltage value stored in the non-volatile storage means And a limit operation control means for stopping a control signal to the fan motor control means so as to stop the driving of the fan motor based on the restriction state determination by the restriction state determination means. When the fan motor voltage suddenly rises and the voltage limiting means limits the fan motor voltage to the first voltage or lower, the first voltage value is reached by a signal from the voltage detecting means after that. The control means that has determined the restricted state stops the fan motor operation by stopping the control signal to the fan motor control means.

  According to a fourth aspect of the present invention, in the fan motor control device according to any one of the first to third aspects, the abnormality determination means determines an abnormal state based on the determination of the abnormal state. An abnormality notifying means for notifying abnormality is provided.

  According to the fan motor control device of the first aspect, when the voltage applied to the fan motor reaches the first voltage value, which is a predetermined limit voltage, it operates in hardware, and the voltage applied to the fan motor is The voltage limiting means for limiting the voltage to one voltage value or less is provided, and the control means is an abnormal voltage value exceeding an appropriate range of the voltage applied to the fan motor, and is predetermined as a value lower than the first voltage value. Non-volatile storage means for storing two voltage values, abnormality determination means for determining an abnormal state in which the voltage value detected by the voltage detection means has reached the second voltage value stored in the nonvolatile storage means, and abnormality determination means And an abnormal operation control means for changing the control signal to the fan motor control means so as to lower the applied voltage to the fan motor based on the abnormality determination by the When the applied voltage reaches the first voltage value, the voltage applied to the fan motor is limited to the first voltage value and the second voltage value by the function of the voltage limiting means. The control means that has determined the abnormal state that has reached the two voltage values changes the control signal transmitted to the fan motor control means, thereby reducing the voltage applied to the fan motor or stopping the operation of the fan motor. . That is, it is possible to improve the reliability of the apparatus by accurately detecting the operation state of the fan motor from the voltage applied to the fan motor and making the fan motor control apparatus capable of appropriate operation control.

  According to the fan motor control device of the second aspect, before the fan motor voltage gradually increases and the voltage limiting means operates, the control means uses the signal from the voltage detection means to set the second voltage value. If it is determined that the abnormal state has been exceeded, the control means changes the control signal to the fan motor control means so that the applied voltage to the fan motor is within the second voltage. Returning is possible, and convenience as a device is increased.

  According to the fan motor control device of the third aspect, the control means determines an abnormal state in which the fan motor voltage exceeds the second voltage value from the detection information of the voltage detection means, and controls the fan motor control means. The voltage limiting means functions at a response speed sufficiently faster than the time required to change the signal, and the control means includes nonvolatile storage means for storing the first voltage value in addition to the second voltage value; Based on the restriction state determination means for determining the restriction state where the voltage value detected by the voltage detection means has reached the first voltage value stored in the nonvolatile storage means, and the restriction state determination by the restriction state determination means, the fan motor And a limit operation control means for stopping the control signal to the fan motor control means so as to stop the drive, so that the fan motor voltage rises rapidly and the voltage restriction means When the motor voltage is limited to the first voltage or lower, the control means that determines the restricted state that has reached the first voltage value by the signal from the voltage detection means stops the control signal to the fan motor control means. Then, since the fan motor operation is stopped, it is possible to avoid a situation where the operation is continued without knowing the cause of the increase in the applied voltage and the fan motor becomes inoperable. Thereby, it becomes possible to further improve the reliability as a fan motor control device.

  Further, according to the fan motor control device of the fourth aspect, since the abnormality notifying means for notifying the abnormality of the fan motor is provided based on the fact that the abnormality determining means determines the abnormal state, It can be notified that the control signal to the fan motor control means has been changed by the intervention of the control means. As a result, it is possible to promptly notify the abnormality of the fan motor, and it is possible to prompt appropriate and prompt countermeasures.

  Hereinafter, preferred embodiments of the present invention will be described in detail with reference to the accompanying drawings. FIG. 1 is a diagram showing a schematic configuration of an embodiment of a fan motor control device of the present invention, which is an example applied to control of a fan motor in a bathroom heating dryer.

  The fan motor control device 1 is composed of a high voltage unit 1a and a low voltage unit 1b. Since the high voltage unit 1a and the low voltage unit 1b are separated by dividing the GND line, the fan motor FM is driven. The PWM signal (control signal) from the control microcomputer 2 as the control means is transmitted to the fan motor control means 3 by the first photocoupler PC1, and the fan motor control means 3 generates from the commercial AC power supply by this PWM signal. The DC 140V power supply is turned on / off, and an arbitrary AC voltage is applied to the fan motor (FM) 4.

  The voltage applied to the fan motor 4 as described above is fed back to the fan motor control means 3 at an appropriate voltage dividing ratio, and the voltage detection means 5 detects the voltage. In order to transmit the voltage detected by the voltage detection means 5 from the high voltage section 1a to the low voltage section 1b, the ON duty is changed to a pulse waveform and transmitted through the second photocoupler PC2. In the low voltage section 1b, The signal is sufficiently integrated to provide an AD input to the control microcomputer 2.

  Further, the voltage applied to the fan motor 4 can be detected by the voltage limiting means 6 comprising a voltage limiter circuit, and the voltage applied to the fan motor 4 reaches a first voltage value that is a predetermined limiting voltage. Thus, the voltage limiting means 6 operates in a hardware manner, and controls the output voltage of the fan motor control means 3 so as to limit the voltage applied to the fan motor 4 to the first voltage value or less. As a result, the circuit constituting the fan motor control means 3 and the fan motor 4 are prevented from being damaged.

  Note that the response speed of the voltage limiting means 6 that operates in hardware can follow a sudden voltage rise. At least, the control microcomputer 2 determines that the applied voltage of the fan motor 4 is based on the detection information of the voltage detection means 5. It is possible to perform voltage limit control to the fan motor control means 3 at a response speed sufficiently faster than the time required to determine an abnormal state exceeding two voltage values and change the control signal to the fan motor control means 3. Is.

  The nonvolatile RAM area provided in the control microcomputer 2 that comprehensively controls the operation / stop of the fan motor control device 1 has an abnormal voltage value exceeding the appropriate range of the voltage applied to the fan motor 4. A predetermined second voltage value is stored as a value lower than the first voltage value, and when the voltage applied to the fan motor 4 detected by the voltage detection means 5 reaches the second voltage value, this is regarded as an abnormal state. The control signal to the fan motor control means 3 is changed so that the voltage applied to the fan motor 4 is decreased. That is, in the present embodiment, each function as the nonvolatile storage means, the abnormality determination means, and the abnormal operation control means is realized by the control microcomputer 2 and its control program.

  Note that the control signal (PWM signal) change control by the abnormal operation control means of the control means (control microcomputer 2) at the time of abnormality determination is performed by lowering the voltage applied to the fan motor 4 to bring the fan motor current to an appropriate range. This includes control for returning and continuing the operation of the fan motor 4, control for stopping the fan motor 4 by stopping the output of the control signal to the fan motor control means 3, and the like.

  For example, the control microcomputer 2 that has detected that the fan motor current has reached the second voltage value lowers the duty ratio of the PWM signal (lowers the pulse width of the PWM signal) and the fan motor control means 3 to the fan motor 4. When the feedback voltage control based on the value detected by the voltage detection means 5 is performed by reducing the applied voltage to the voltage detection means 5 so that the detection voltage value by the voltage detection means 5 becomes less than the second voltage value, the fan motor 4 It is possible to automatically return to the normal operation while continuing the drive control, and the convenience as the fan motor control device 1 can be enhanced.

  On the contrary, in order to give priority to safety, the control microcomputer 2 stops the PWM signal and terminates the voltage application by the fan motor control means 3 at the time of abnormality determination so that the operation of the fan motor 4 is completely stopped. Anyway. Alternatively, the control may be such that the low speed operation is temporarily performed and then the normal operation is restored. That is, how to specifically set the abnormal operation control performed by the abnormal operation control means after the abnormality determination is within the category of design matters.

  Moreover, at the time of abnormal state determination, the abnormality notification information is transmitted from the remote controller 6 to the information notification device 1c, so that the information notification device 1c notifies that the fan motor 4 is abnormal. The information alarm device 1c is provided at a position that is easily noticeable, such as a bathroom inner wall away from the housing in which the high-voltage unit 1a and the low-voltage unit 1b are stored. In the mode of notification by the information notification device 1c, character information such as “fan motor abnormality” is displayed on the liquid crystal panel, together with visual notification that is easy to call attention such as blinking of a red lamp.

  Note that the configuration of information notification performed by the control microcomputer 2 is not limited to wireless communication using infrared rays or the like, but can also be wired communication in which a cable is laid up to a location where the information notification device is located, and visual notification. However, the present invention is not limited to this, and audio notification by a speaker may be used, or visual notification and auditory notification may be performed simultaneously. Alternatively, a warning sound may be output from an information notification terminal that can be carried by a person, or the information notification terminal may be vibrated.

  On the other hand, the applied voltage to the fan motor 4 rapidly increases and the applied voltage to the fan motor 4 reaches the first voltage value before returning to the normal operation state by the applied voltage reduction control by the control microcomputer 2. When the limiting unit 6 operates (the voltage applied to the fan motor 4 is limited to the first voltage or lower), the voltage applied to the fan motor 4 is limited to the first voltage or lower, and then the voltage detection unit 5 The control microcomputer 2 determines that the limit state has reached the first voltage value by the signal, stops the control signal to the fan motor control means 3, stops the fan motor operation, and causes the increase in the applied voltage. The situation where the operation of the fan motor 4 is made impossible by continuing the operation while being unknown is avoided in advance. In other words, in the present embodiment, the control microcomputer 2 and its control program realize each function as the nonvolatile storage means, the restricted state determining means, and the restricted time operation control means.

  The control by the operation control means at the time of limitation is not limited to the control signal to the fan motor control means 3 immediately stopped and the operation of the fan motor 4 is completely stopped, and various operation modes are adopted. It doesn't matter. For example, even after determining that the detection voltage of the voltage detection unit 5 is in the limit state where the detection voltage is equal to or higher than the first voltage value, the control microcomputer 2 applies the fan motor control unit 3 so as to reduce the voltage applied to the fan motor 4. If the control signal continues to be transmitted, and the voltage value detected by the voltage detection means 5 has not yet returned to less than the second voltage value at the time when a predetermined period of a predetermined time has elapsed since the determination of the control state, Operation control that completely stops transmission of the control signal to the fan motor control means 3 may be employed. In such a case, in a case where the applied voltage of the fan motor 4 instantaneously reaches the first voltage value due to a transient factor without danger, automatic operation is automatically performed without bothering humans. Can be restored.

  Further, the first voltage value used for the operation at the time of restriction and the second voltage value used for the operation at the time of abnormality may be arbitrarily set according to the setting of the safety range and the danger range during the normal operation of the fan motor 4. Is also a category of design matters.

It is a schematic block diagram of the fan motor control apparatus which concerns on this invention.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 Fan motor control apparatus 1a High voltage | pressure part 1b Low voltage | pressure part 1c Information indicator 2 Control microcomputer 3 Fan motor control means 4 Fan motor 5 Voltage detection means 6 Voltage limiting means 7 Remote control PC1 1st photocoupler PC2 2nd photocoupler

Claims (4)

A control unit that comprehensively controls the driving / stopping of the fan motor, and a voltage based on a control signal from the control unit is applied to the fan motor, and the applied voltage fed back is matched with a voltage based on the control signal. And a fan motor control means for controlling a voltage applied to the fan motor, and a voltage control type fan motor control device comprising:
Voltage detection means for detecting a voltage applied to the fan motor;
Voltage limiting means for operating in a hardware manner when the voltage applied to the fan motor reaches a first voltage value that is a predetermined limiting voltage, and for limiting the applied voltage to the fan motor to be equal to or lower than the first voltage value;
Provided,
Control means for receiving the voltage value detected by the voltage detection means,
A non-volatile storage means for storing a second voltage value that is an abnormal voltage value exceeding an appropriate range of the applied voltage to the fan motor and that is lower than the first voltage value;
An abnormality determination means for determining an abnormal state in which the voltage value detected by the voltage detection means has reached the second voltage value stored in the nonvolatile storage means;
Based on the abnormality determination by the abnormality determination means, an abnormal-time operation control means for changing the control signal to the fan motor control means so as to reduce the voltage applied to the fan motor;
A fan motor control device comprising:   If the control means determines that the abnormal state exceeds the second voltage value by the signal from the voltage detection means before the voltage limiting means operates, when the fan motor voltage gradually increases, the control means 2. The fan motor control device according to claim 1, wherein the control signal to the fan motor control means is changed so that the voltage applied to the motor is less than the second voltage. It is sufficiently faster than the time required for the control means to determine an abnormal state where the fan motor voltage exceeds the second voltage value from the detection information of the voltage detection means and to change the control signal to the fan motor control means. Let the voltage limiter function at the response speed,
The control means includes
Nonvolatile storage means for storing a first voltage value in addition to the second voltage value;
Restriction state determination means for determining a restriction state in which the voltage value detected by the voltage detection means has reached the first voltage value stored in the nonvolatile storage means;
Based on the restriction state determination by the restriction state determination means, the operation control means at the time of restriction for stopping the control signal to the fan motor control means so as to stop the drive of the fan motor;
With
When the fan motor voltage suddenly rises and the voltage limiting means limits the fan motor voltage to the first voltage or less, a restriction state where the first voltage value is reached by a signal from the voltage detection means thereafter. 3. The fan motor control device according to claim 1, wherein the control means that has determined whether the fan motor operation is stopped by stopping a control signal to the fan motor control means. 4. 4. The fan motor according to claim 1, further comprising an abnormality notifying unit that notifies an abnormality of the fan motor based on the abnormality determining unit determining an abnormal state. 5. Control device.

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