KR100697092B1 - Driving circuit for motor - Google Patents

Abstract

The present invention relates to a motor driving circuit which is applied to a motor for operating a drain pump of a washing machine to enable operation regardless of the frequency of the driving power input.

Frequency analysis means for analyzing the frequency of the power input from the external power supply to the motor to determine whether it is 50 Hz or 60 Hz; A voltage adjusting means which forms a closed circuit together with the motor and the power supply unit, and phase-controls a voltage waveform supplied from the power supply unit to adjust the voltage to correspond to the type of motor and apply the voltage to the motor; And checking whether the type of motor applied to the system is 50 Hz or 60 Hz, and outputting a phase control signal to the voltage adjusting means according to the determination result of the frequency analyzing means so that the voltage applied to the motor is changed. To a microcomputer; characterized in that it comprises a.

Washing machine, drain pump, power frequency, common motor, frequency analysis, triac

Description

Motor driving circuit {Driving circuit for motor}             

1 is a view showing the configuration of a motor driving circuit according to the prior art;

2 is a view showing the configuration of a motor driving circuit according to an embodiment of the present invention;

Figure 3 is a view showing the waveform of the power applied to the motor in accordance with the power supply frequency during operation of the present invention.

<Description of Symbols for Main Parts of Drawings>

10: motor 20: power supply

30: triac 40: frequency analyzer

50: micom

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a motor driving circuit, and more particularly, to a motor driving circuit which is applied to a motor for operating a drain pump of a washing machine so that operation can be performed regardless of the frequency of a driving power input.

General households are supplied with a voltage of 110V or 220V. Even when the same voltage is supplied in each country, a frequency of 50 kHz or 60 kHz is used.

In general, a motor includes a rotor and a stator. Since the rotor uses a permanent magnet with multipolar magnetization, a plurality of coils are disposed in the stator to correspond to the multipoles of the rotor at predetermined intervals. do. At this time, the rotor is rotated by supplying power to the stator to generate magnetic force, and since the change in the magnetic force of the stator according to the frequency of the power influences the characteristics of the motor, the 50 kW motor and the 60 kW motor are used separately. .

In the following description, a case where AC 220V is supplied will be described as an example.

In the case of the motor applied to the drain pump of the washing machine, when the motor for 50 kW is operated with a power of 60 kW, the rotation is performed, but a desired operation is not made, and thus a drainage operation becomes impossible.

On the other hand, when the 60-Hz motor is operated with a 50-kV power supply, no problem occurs in drainage operation, but the temperature inside the motor increases due to the resistance difference, thereby reducing the motor characteristics and shortening the life of the motor. Problem occurs.

For these reasons, manufacturers of home appliances are equipped with a motor corresponding to the frequency of the power source being used in the country to export, and design the power supply accordingly.

However, the production line produces a motor for 50 kHz and 60 kHz, and must be correctly mounted on the home appliances, there is a problem that requires a variety of production lines.

In order to solve the above problems, a motor driving circuit is required to allow the motor to be driven in common regardless of the frequency of the input power.

1 is a view showing the configuration of a motor driving circuit according to the prior art.

Referring to FIG. 1, reference numeral 1 denotes a motor applied to a drain pump, 2 denotes a power supplied from the outside for operating the motor 1, and 3 denotes a power on / off depending on whether the washing machine is drained. A switch for connecting the power supply 2 to the motor 1 in the drainage operation is shown.

In the conventional motor driving circuit as described above, when the washing machine proceeds to enter the drainage mode, the switch 3 is turned on to connect the power supply 2 to the motor 1 so that the drain pump is connected. To work. As a result, since the operation is performed irrespective of the input frequency, the above-described drainage impossibility problem and motor temperature rise problem cannot be solved.

The present invention has been made to solve the above problems, the purpose of which is to analyze the frequency of the input power source and adjust the voltage applied to the motor by phase-controlling the power waveform accordingly 50 kHz and It is to provide a motor driving circuit that can be used in common 60㎐.

Motor driving circuit according to the present invention for achieving the above object, the frequency analyzer for determining which frequency of the power source input from the power source corresponds to 50 kHz and 60 kHz to form a closed circuit together with the motor and the power supply unit Voltage control means for phase-controlling a waveform of a voltage supplied from the power supply unit according to an input phase control signal, and applying the voltage to the motor; and as a result of the frequency analyzer determining that the frequency of the power source is 60 Hz and the frequency of the power source. Is 50 Hz, and outputs different phase control signals to the voltage adjusting means to control the voltage applied to the motor.

At this time, the voltage adjusting means may be connected between the motor and the power supply, it may include a triac (triac) for receiving the phase control signal to the gate terminal.

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

2 is a diagram illustrating a configuration of a motor driving circuit according to an embodiment of the present invention.

Referring to FIG. 2, reference numeral 10 denotes a 60 kW motor applied to a drain pump of a washing machine, 20 denotes a power supply unit supplied from the outside for operating the motor 10, and 30 denotes the motor 10 and The triac which forms a closed circuit with the power supply part 20 is shown.

In addition, reference numeral 40 denotes a frequency analyzer for determining whether 50 kHz or 60 kHz by analyzing the frequency of the power output from the power supply unit 20, 50 indicates whether the type of the motor 10 is 50 kHz Or a microcomputer for outputting a phase control signal for determining the conduction time to the gate terminal of the triac 30 according to the determination result of the frequency analyzer 40 after checking whether the signal is for 60 Hz.

Referring to the operation of the present invention having the configuration as described above are as follows.

First, a manufacturer of a washing machine assumes that a 60 Hz motor 10 is mounted on a drain pump in a production line, and an AC power source having a frequency of 50 Hz or 60 Hz is supplied from an external power supply unit 20.

In addition, since the triac 30 is a reverse voltage even when a voltage is applied in either direction, the current does not flow. However, when the small current is supplied through the gate terminal, the triac 30 operates.

On the other hand, when the washing machine proceeds to the drainage mode, the frequency analyzer 40 analyzes the frequency of the power output from the power supply unit 20 to determine whether it is 50 kHz or 60 kHz. In this case, the microcomputer 50 determines the state of the triac 30 according to the determination result of the frequency analyzer 40. If the microcomputer 50 is 60 Hz, the position at which the positive and negative half periods are started In FIG. 3, the phase control signal is output to the gate terminal of the triac 30 so as to be conductive so that a voltage having a waveform as shown in (a) of FIG. 3 is applied to the motor 10. That is, all voltages of the power supply unit 20 are applied.

On the other hand, if the frequency of the power supply unit 20 is 50 kHz, the microcomputer 50 delays the predetermined time at the position where the positive and negative half cycles start, and then the gate of the triac 30 A phase control signal is output to the terminal and conducted so that a voltage having a waveform as shown in FIG. 3B is applied to the motor 10. At this time, when the phase control is performed as described above, the voltage applied to the motor 10 is lowered as compared with the case of 60 kV to prevent the temperature rise in the motor 10. As a result of the applicant's experiment, it was found that when the frequency of the power source is 50 kHz, it is preferable that the voltage of the power supply unit 20 is applied to the motor 10 about 5/6.

As described above, the motor driving circuit of the present invention applies a 60 kW motor to a drain pump, and when the frequency of the power supply unit is 50 kW, the voltage is lowered to prevent the temperature increase inside the motor, thereby lowering the motor characteristics and the service life. It prevents shortening and at the same time has the effect that can be used in common at 50㎐ and 60㎐ as a 60㎐ motor.

In addition, it is possible to improve the ease of use for the washing machine by making the drainage operation smoothly regardless of the frequency of the input power source.

Claims (2)

A frequency analyzer for determining which frequency of the power input from the power supply unit corresponds to 50 Hz or 60 Hz; A voltage adjusting means which forms a closed circuit together with a motor and the power supply unit, and phase-controls a waveform of a voltage supplied from the power supply unit according to an input phase control signal to the motor; And As a result of the determination of the frequency analyzer, when the frequency of the power source is 60Hz and when the frequency of the power source is 50Hz, a microcomputer for controlling the voltage applied to the motor by outputting a different phase control signal to the voltage adjusting means. Motor drive circuit comprising a. The method of claim 1, The voltage adjusting means is connected between the motor and the power supply unit, characterized in that it comprises a triac (triac) for receiving the phase control signal to the gate terminal.

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