JP2007178079A - Control device for refrigerator - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To prevent abnormal control of a control load outputting a signal according to power supply frequency by judging abnormality when pulses generated at a zero point of power supply voltage waveform are abnormally input because of noise and the like. <P>SOLUTION: This control device for a refrigerator comprises a zero-cross pulse generating means 1 generating a pulse signal at every time when the power supply voltage waveform passes the zero point, a zero-cross pulse determining means 2 determining the input of a zero-cross pulse signal, and a control means 3 controlling the output of AC load in synchronization with the zero point of power supply voltage waveform. The abnormality is determined when an interval of input of the zero cross pulse signals is not within a prescribed time, thus erroneous determination can be prevented when the zero cross pulse signal is abnormally input because of noise and the like, and the abnormal control of AC load in synchronization with the zero point of the power supply voltage waveform can be prevented. <P>COPYRIGHT: (C)2007,JPO&INPIT

Description

  The present invention relates to a refrigerator provided with a control device that detects a zero point of a power supply voltage waveform and controls an AC load synchronized with the zero point.

  Conventionally, as this type of control device, there is one that detects the power supply frequency and controls the rotational speed of the fan by phase control (see, for example, Patent Document 1).

  Hereinafter, the conventional refrigerator control device will be described with reference to the drawings.

FIG. 4 shows a block diagram of a conventional refrigerator control device. As shown in FIG. 4, in the conventional control device, the compressor 102 is operated and stopped based on the output of the thermistor 101, the rotation speed is determined by the fan rotation speed determination means 103, the waveform of the power supply 104 is input, and the power supply voltage Determine the power supply frequency by counting the pulses generated at the zero point of the waveform and determining the power supply frequency by determining Tp ≦ 9 msec × 60 Hz for the count number and Tp> 9 msec × 50 Hz for the count number based on the time Tp when the specified number is reached The power frequency is detected by the means 105 and the rotation speed of the fan 106 is controlled by the control means 107 by phase control.
JP-A-5-302775

  However, in the conventional configuration described above, a control load that erroneously determines when a pulse signal generated at the zero point of the power supply waveform at the time of power supply frequency determination becomes an abnormal signal due to noise or the like, and outputs a signal corresponding to the power supply frequency. There was a problem that the control of was not normal.

  The present invention solves the conventional problem, and when a pulse signal generated at a zero point of a power supply voltage waveform becomes an abnormal signal due to noise or the like, a control load that determines that it is abnormal and outputs a signal corresponding to the power supply frequency It aims at providing the control apparatus of the refrigerator which prevents that control of becomes abnormal.

  In order to solve the above-described conventional problems, the present invention includes a zero-cross pulse generation unit that generates a pulse signal each time a power supply voltage waveform passes through a zero point, and a zero-cross pulse determination unit that determines a zero-cross pulse signal input. Control the AC load synchronized with the zero point of the power supply voltage when the pulse signal input interval is within the predetermined time. If it is not within the predetermined time, the AC load is determined to be abnormal, and the AC load control is stopped and displayed by the display means. It is configured.

  In the present invention, when the zero cross pulse signal input becomes abnormal due to noise or the like by judging that the interval of the zero cross pulse signal generated every time the power supply voltage waveform passes through the zero point is not within a predetermined time, it is abnormal. It is possible to prevent erroneous determination and to prevent abnormal control of the AC load synchronized with the zero point of the power supply voltage waveform.

  According to the first aspect of the present invention, the zero cross pulse generating means for generating a pulse signal every time the power supply voltage waveform passes through the zero point, the zero cross pulse determining means for determining the input of the zero cross pulse signal, and the zero point of the power supply voltage waveform are synchronized. Control means to control the output of the AC load, and if the zero-cross pulse signal input interval is not within the specified time, it is determined as abnormal, thereby preventing erroneous determination when the zero-cross pulse signal input becomes abnormal input due to noise, etc. it can.

  According to a second aspect of the present invention, in the first aspect of the invention, when the output of the AC load synchronized with the zero point of the power supply voltage waveform is started, the interval of the zero cross pulse signal input is within a predetermined time. The load can be accurately controlled by controlling the AC load synchronized with the zero point of the power supply voltage after determining the predetermined number of times.

  According to a third aspect of the present invention, in the first or second aspect of the present invention, when the zero-cross pulse signal input interval is outside a predetermined time, the control of the AC load synchronized with the zero point of the power supply voltage is stopped to cause a malfunction. Can be prevented.

  According to a fourth aspect of the present invention, in the invention according to any one of the first to third aspects, when the zero-cross pulse signal input interval is outside a predetermined time, it is determined that there is an abnormality and the full load is stopped to display the display means. You can be notified even if there is no.

  The invention according to claim 5 comprises the display means according to any one of claims 1 to 4, wherein when the interval of the zero cross pulse signal input is outside a predetermined time, it is determined to be abnormal and displayed. Can do.

  Embodiments of the present invention will be described below with reference to the drawings. In addition, about the same structure as the past, the same code | symbol is attached | subjected and detailed description is abbreviate | omitted.

(Embodiment 1)
FIG. 1 is a block diagram of the refrigerator control device according to Embodiment 1 of the present invention, FIG. 2 is a waveform diagram for explaining the operation of the refrigerator control device of the same embodiment, and FIG. It is a flowchart which shows operation | movement of the control apparatus of the refrigerator of the form. This will be described below with reference to FIGS.

  In FIG. 1, the zero cross pulse generating means 1 inputs the voltage waveform of the AC power source 104 shown in FIG. 2A and generates a rectangular wave AC synchronized zero cross pulse signal shown in FIG. 2B. It is. The zero cross pulse determining means 2 measures the interval Tph of the zero cross pulse signal, and determines that it is abnormal if the interval Tph of the zero cross pulse signal input is not within a predetermined time. The control means 3 controls the output setting of the control load 5 (an internal fan, a compressor, an internal temperature compensation heater, a refrigerant switching valve, etc.) based on each internal temperature detection value by the thermistor 4.

  The control means 3 includes a zero cross point of the power supply voltage waveform detected by the zero cross pulse determination means 2 in the control load 5 and an output signal of an AC load synchronized with the zero point of the power supply voltage waveform (hereinafter referred to as a load output signal). Synchronously output to the driving means 6, and when it is determined that the zero-cross pulse signal input interval is abnormal, the control of the AC load synchronized with the zero point of the power supply voltage is stopped. The drive means 6 supplies a drive voltage to the control load 5 based on the load output signal. Examples of the load output setting, the load output signal, and the load drive voltage waveform (the waveform of the drive voltage supplied to the control load) are shown in FIGS. 2 (c), 2 (d), and 2 (e). The display means 7 displays when it is determined that the zero-cross pulse signal input interval is abnormal.

  Operation of the refrigerator control apparatus configured as described above will be described with reference to FIG. First, in step 100, the zero cross pulse determination means 2 starts a zero cross input determination timer for measuring the interval Tph of the zero cross pulse signal input. Next, in step 101, the rising edge or falling edge of the zero cross pulse signal input, which is the zero point of the power supply voltage, is detected. Here, as shown in FIG. 2B, the case where the time Tph from the rising edge to the next rising edge is measured will be described. If a rising edge is detected in step 101, a zero cross input determination timer value is read in step 102. Next, at step 103, the zero cross pulse signal input interval Tph is measured from a value obtained by subtracting the previous read timer value from the current read timer value. Next, in step 104, it is determined whether the zero-cross pulse signal input interval Tph is within a predetermined range. For example, when the power source frequency is set to ± 3 Hz, it is determined whether it is in the range of 15.87 msec to 17.54 msec in the case of 60 Hz or in the range of 18.87 ms to 21.28 msec in the case of 50 Hz. . In step 104, when the zero cross pulse signal input interval Tph is within the determination range, it is determined normal, and when it is outside the determination range, it is determined as abnormal.

  As described above, in a refrigerator having a control device that controls the output of an AC load synchronized with the zero point of the power supply voltage waveform, the zero cross pulse signal is determined by determining that the zero cross pulse signal input interval is not within a predetermined time. An erroneous determination can be prevented when the input becomes abnormal due to noise or the like.

  In step 104, the zero cross pulse determining means 2 determines whether the zero cross pulse signal input interval is within a predetermined range. If normal, the step 200 counts the number of times the input is normal.

  When the zero-cross pulse signal input interval is outside the predetermined range in step 104, the normal number of inputs is cleared in step 203.

  Next, in step 201, it is confirmed whether the number of times when the input is normal is a predetermined number. The output signal is output to the drive means 6 in synchronization with the zero cross point of the power supply voltage waveform detected by the zero cross pulse determination means 2. For example, when the number of normal judgments is 2 and the drive voltage waveform of the load synchronized with the zero point of the power supply voltage waveform is the output shown in FIG. 2E, the control means 3 is as shown in FIG. When the zero-cross pulse signal input interval continues twice after the load output setting is set to ON, the load output signal is output to the drive means 6 as shown in FIG. A voltage having a load drive voltage waveform as shown in 2 (e) is applied.

  As described above, it is possible to accurately control the load by controlling the AC load in synchronization with the zero point of the power supply voltage after determining that the interval of the zero cross pulse signal input is within a predetermined time a predetermined number of times. it can.

  In step 104, when the zero-cross pulse signal input interval is outside the predetermined range, it is determined that there is an abnormality, and in step 300, the control of the AC load synchronized with the zero point of the power supply voltage is stopped. Malfunctions can be prevented when an abnormal input occurs.

  Further, when the zero-cross pulse signal input interval is outside the predetermined range in step 104, it can be notified even when there is no display means by determining that it is abnormal and stopping all control loads in step 400.

  Further, when the zero cross pulse signal input interval is outside the predetermined range in step 104, it is determined that there is an abnormality, power supply voltage abnormality display setting is performed in step 500, and display unit 7 can display and notify it in step 501.

  As described above, the refrigerator control device according to the present invention makes an error when the zero cross pulse signal input becomes abnormal due to noise or the like by determining that the zero cross pulse signal input interval is not within a predetermined time. Since the determination can be prevented, the present invention can be applied to all control devices that detect the zero point of the power supply voltage waveform and control the AC load synchronized with the zero point.

The block diagram of the control apparatus of the refrigerator in Embodiment 1 of this invention Waveform diagram for explaining the operation of the refrigerator control device according to Embodiment 1 of the present invention. The flowchart of the control apparatus of the refrigerator in Embodiment 1 of this invention Block diagram of a conventional refrigerator control device

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 Zero cross pulse generation means 2 Zero cross pulse determination means 3 Control means 7 Display means

Claims (5)

  Zero cross pulse generating means for generating a pulse signal every time the power supply voltage waveform passes through the zero point, zero cross pulse determining means for determining the input of the zero cross pulse signal, and control for controlling the output of the AC load synchronized with the zero point of the power supply voltage waveform And a control device for a refrigerator that includes means for determining that the interval between zero-cross pulse signal inputs is not within a predetermined time.   When starting output of an AC load synchronized with the zero point of the power supply voltage waveform, control the AC load synchronized with the zero point of the power supply voltage after determining that the interval of the zero cross pulse signal input is within a predetermined time. The refrigerator control device according to claim 1, comprising control means for performing the operation.   3. The refrigerator control device according to claim 1, further comprising control means for stopping control of the AC load synchronized with a zero point of the power supply voltage when the interval of the zero cross pulse signal input is outside a predetermined time.   The control device for a refrigerator according to any one of claims 1 to 3, further comprising a control unit that determines that an abnormality occurs when the interval of zero-cross pulse signal input is outside a predetermined time and stops and notifies all loads.   5. The refrigerator control device according to claim 1, further comprising a display unit, wherein when the interval between zero-cross pulse signal inputs is outside a predetermined time, it is determined to be abnormal and displayed.

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