JP2011158169A - Air-conditioner - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To solve the problem in which unnecessary electricity is consumed because electric power is always supplied even if an actuator is stopped other than standby state. <P>SOLUTION: An air-conditioner includes: a voltage conversion means 2 that converts AC voltage for commercial power supply from a rectified high-voltage direct current voltage into low-voltage output voltage; a fan motor 6 that operates by assuming direct current as control power supply outputted from the voltage conversion means, and in which the number of rotation is controlled by switching the high-voltage direct current and applying it to a motor winding; a variable means 7 that varies the motor control power supply voltage; and a control part 8 that receives a start-up instruction, outputs the motor an instruction of the number of rotation and inputs a variable width signal into the variable means and operates by making a micro computer that varies the control power supply voltage to the motor, thereby decreasing the control power supply voltage of the fan motor when fan motor suspension condition is met in also conditions other than a standby condition. <P>COPYRIGHT: (C)2011,JPO&INPIT

Description

  The present invention relates to an air conditioner that reduces standby power and actuator stop power by controlling a fan motor control power supply.

  The fan motor employs a motor drive unit that employs a PWM drive method in which high-voltage direct current is turned on and off to create a three-phase alternating current and applied to the motor winding.

In this method, a PWM drive circuit in which a PWM control unit and a drive element are combined in the drive unit or an IC in which these are packaged is used. These circuits or ICs require a control power supply for operation. On the other hand, the control power supply for controlling the air conditioner using the control power supply or microcomputer as a core is a DC voltage obtained by full-wave rectification of a commercial power supply. Is used as a primary input to create a low-voltage output voltage on the secondary side.

  Since the switching power supply has a certain conversion efficiency when converted to the secondary output, the power that is added to the secondary power consumption by the conversion loss is consumed on the primary side.

  Even when the control circuit is not operating, the secondary circuit including the control circuit having the microcomputer as a core has a certain power loss as long as power is supplied. This state is defined as standby power loss.

  Conventional air-conditioning air has improved the conversion efficiency of the control power supply to reduce standby power loss, cuts unnecessary circuits, reduces the operation of the control circuit, and reduces the average power by intermittent operation of the load. It was.

  For example, Patent Literature 1 or Patent Literature 2 has two power sources, namely, a control circuit power source and a load driving power source, and attempts to reduce power by shutting off the load driving power source during standby.

  Moreover, in patent document 3, the electric power which a microcomputer consumes is reduced by making the operation speed of the microcomputer which controls an air conditioner at the time of a standby slower than operation.

  Moreover, in patent document 4, the electric power at the time of standby was reduced by interrupting | blocking the high voltage circuit of the fan motor drive IC which is a power loss source.

The fan motor generally employs a drive system called a high voltage PWM system, and FIG. 4 shows a fan motor drive configuration diagram of an air conditioner in the prior art. This fan motor uses a control power supply for a low-voltage DC voltage output by a voltage conversion means 2 represented by a switching power supply that converts a high-voltage DC voltage obtained by rectifying an AC voltage of a commercial power supply from a rectifier 1 into at least one low-voltage output voltage. Use as The PWM control unit 3 to which the control power is applied is activated by the low-voltage DC voltage and generates a PWM signal according to a command from the microcomputer. Further, the high-voltage direct current is turned on / off by the PWM signal to create a three-phase alternating current and is applied to the motor winding to constitute a motor drive unit 4 that performs PWM drive. In these configurations, a motor drive unit and a PWM control unit may be combined with individual components and circuits, or an IC that is packaged as a PWM drive IC may be used.

  On the other hand, this PWM drive unit requires a power supply for control as described above. This means that there is a slight power loss inside the circuit. Due to the characteristics of the air conditioner, the air conditioner is often stored with the outlet connected throughout the year. Therefore, even when not operating as air conditioning, there is a power loss, which causes a disadvantage to the user even though he does not work as standby power. Part of the cause of this standby power is the loss of the control power source existing in the PWM drive unit of the fan motor described above.

  As a means for reducing this standby power, there is a method of providing a switch 15 such as a relay in the control power supply as shown in FIG. The problem with this method is the inrush of power when returning from the standby state. Generally, the control unit is provided with a capacitance component such as a capacitor for stabilizing the power supply in the power input unit. When the standby power reduction switch is configured to shut off the power supply during standby, the stabilization capacitor is charged when returning from standby. Therefore, a large inrush current flows at this moment, and this means that parts such as a rectifier diode with an inrush current resistance must be used to ensure a margin of power capacity so that the output of the voltage conversion means can withstand the inrush. It was the cause of the cost increase.

JP 2006-69992 A JP 2000-55439 A Japanese Patent No. 3483483 Japanese Patent No. 4153586

  As described above, in the air conditioners described in Patent Documents 1, 2 and 4, since the load is shut off during standby, an inrush current flows from the power source to the load when returning from the standby state. If a capacitor is inserted on the side to stabilize the power supply, a large inrush current occurs. Since the generation of a large inrush current results in a large load on the switching power supply, a component with sufficient derating is required to ensure that the power supply capacity is not necessary and damage caused by a large inrush current is required. And had problems that resulted in increasing the cost of the circuit.

  In addition, the air conditioner described in Patent Document 3 has a problem that it is necessary to adopt a microcomputer having a special function that can arbitrarily change the operation speed.

  On the other hand, the standby state defined here refers to a state where the air conditioner has been completely stopped after the stop command from the remote control etc. has been confirmed. When the fan motor is functioning as a harmony machine but the fan motor is stopped, processing during standby is not performed, and thus there is a problem that internal loss due to the fan motor always exists.

  Also, the dedicated IC that controls the fan motor may become indeterminate, that is, the load drive circuit may become uncontrollable if the control power supply is cut off, and it is inertial while the fan motor is rotating. Even during rotation, there is a problem that the induced voltage of the winding or the reflux current may be destroyed while being applied to the load driving element of the IC.

  The present invention has been made in view of such problems of the prior art, and does not generate a large inrush current when returning from standby, and also reduces power loss due to a microcomputer with a simple configuration. The purpose is to provide an energy-saving air conditioner that reduces power without using parts with special functions and without applying unnecessary costs to circuits and parts.

  In order to achieve the above object, the present invention controls voltage conversion means for converting a high-voltage DC voltage obtained by rectifying an AC voltage of a commercial power supply into at least one low-voltage output voltage, and controls the DC voltage output from the voltage conversion means. A fan motor that operates as a power source, controls the high-speed direct current and applies it to the motor winding to control the rotation speed of the motor, variable means that varies the motor control power supply voltage, and receives an operation start command Provided with a control unit based on a microcomputer that outputs a rotation speed command to the motor and inputs a variable width signal to the variable means to vary the control power supply voltage to the motor, and stops the fan motor even in other than standby conditions If the condition is satisfied, the control power supply voltage of the fan motor is reduced.

  The air conditioner of the present invention has a configuration that does not generate a large inrush current when returning from the standby state, so that standby power can be used without using parts with special functions and without applying unnecessary costs to circuits and parts. In addition, electric power when the actuator is stopped can be reduced.

Fan motor drive block diagram of the air conditioner in Embodiment 1 of this invention (A) Detailed view of the control voltage circuit according to the first embodiment of the present invention (b) Characteristic diagram Configuration diagram in Embodiment 2 of the present invention Fan motor drive configuration diagram of air conditioner in the prior art Detailed view of control voltage switching circuit in the prior art

  The first invention operates as voltage control means for converting a high voltage DC voltage obtained by rectifying an AC voltage of a commercial power source into at least one low voltage output voltage, and the DC voltage output from the voltage conversion means as a control power source, A fan motor that controls the motor speed by switching high-voltage direct current and applying it to the motor winding, a variable means that varies the motor control power supply voltage, and an operation start command that receives the operation start command. And a control unit having a microcomputer as a core for changing the control power supply voltage to the motor by inputting a variable width signal to the variable means and satisfying the fan motor stop condition other than the standby condition. Is a configuration that lowers the control power supply voltage of the fan motor, resulting in a large rush that occurs when returning from standby It is possible to reduce the flow, it is possible to reduce the power consumption as long as conditions that the fan motor is stopped without waiting.

  Further, the second invention is provided with a rotation speed detecting means for constantly monitoring the rotation speed of the fan motor, and the fan motor control IC is destroyed by not lowering the control power supply when the rotation continues due to completion immediately after the instruction to stop the fan motor. This can be prevented.

(Embodiment 1)
1 is a schematic configuration diagram of an air conditioner according to Embodiment 1 of the present invention, FIG. 2A is a detailed diagram of a control voltage circuit, and FIG. 1B is a characteristic diagram thereof.

A voltage conversion means 2 for converting a high-voltage DC voltage obtained by rectifying an AC voltage of a commercial power supply into at least one low-voltage output voltage, and a low-voltage DC voltage output from the voltage conversion means are operated as a control power supply, and the high-voltage DC is switched. A fan motor 6 having a PWM drive unit 5 for controlling the number of rotations of the motor by being applied to the motor winding, a variable means 7 for varying the motor control power supply voltage, and an operation start command being received to rotate the motor. The low voltage direct current output from the voltage conversion means 2 in the configuration of the control unit 8 having a microcomputer which outputs a numerical command and inputs a variable width signal to the variable means to vary the control power supply voltage to the motor. The voltage is converted by the variable means 7 into a voltage V2 necessary for the PWM control unit 3 to operate during normal operation. By applying to the PWM control unit 3 and holding the power consumed by the PWM control unit 3 at the minimum level V1 during standby, the capacitor provided for stabilizing the power supply is charged with a low voltage higher than 0 V from standby. Suppress the inrush current generated by charging the capacitor at the time of recovery, unnecessarily increase the output capacity of the switching power supply that is the voltage conversion means, or use parts with overspec that can withstand excessive power Unnecessary cost increases can be avoided.

  As an example, when V2 = 20V, V1 is in the range of a control power supply voltage in which a voltage of about 0.2V to 2V can achieve both power consumption reduction during standby and suppression of inrush current during return from standby. . This value varies depending on the type of motor driving IC used.

  In general, an electrolytic capacitor is used as a capacitance component. However, when the voltage is applied from 0V, the internal impedance becomes almost zero, so a large charging current is generated as an inrush current. Since the internal impedance is constant and the charging current rises slowly, an excessive inrush current does not occur.

  As a voltage variable method, a pulse waveform shaping circuit is provided in the variable means, a narrow pulse is output from the microcomputer during standby, and a 100% pulse is output when returning from standby, and the voltage variable means configured from the pulse waveform shaping circuit. Thus, a configuration for generating a voltage according to the pulse width is conceivable.

  In the standby state in which all the actuators are stopped in such a configuration, the control power of the fan motor can be reduced by the above control to reduce the power. However, in the air conditioner, the ON timer setting and the heating deice Thus, there is a halfway state in which some functions are operating but the fan motor is stopped. In such a state, there is a waste that the non-functioning actuator is always consuming power. Therefore, in the present invention, the control power supply voltage of the fan motor is reduced when the fan motor stop condition is satisfied even in a condition other than the standby condition. This can reduce unnecessary power consumption.

(Embodiment 2)
FIG. 3 is a schematic configuration diagram of an air conditioner according to Embodiment 2 of the present invention.

  In the second embodiment, the operation state of the fan motor is monitored by the rotation speed detection means 9 that detects the rotation speed of the fan motor, and the behavior of the fan motor that continues to rotate even when the fan motor stop condition is achieved is detected. However, control was performed so as not to lower the control power of the fan motor while the rotation continued. As a result, the control power supply drops during rotation, the control IC falls into an indeterminate state, and is controlled by the current that flows back to the drive element and the high voltage applied to the drive element while it continues to rotate due to inertia. It is possible to prevent the IC from being destroyed.

The air conditioner according to the present invention can also be applied to an air conditioner equipped with an air purifier, an air purifier, or a ventilator.

DESCRIPTION OF SYMBOLS 1 Rectifier 2 Voltage conversion means 3 PWM control part 4 Motor drive part 5 PWM drive part 6 Fan motor 7 Variable means 8 Control part 9 Rotation number detection means

Claims (2)

Voltage conversion means for converting the AC voltage of the commercial power supply from at least one rectified high voltage DC voltage into at least one low voltage output voltage, and the DC voltage output from the voltage conversion means operates as a control power supply, and the high voltage DC is switched. A fan motor whose rotation speed is controlled by being applied to the motor winding, a variable means for varying the motor control power supply voltage, an operation start command is received, and the rotation speed command is output to the motor. A control unit centered on a microcomputer that changes the control power supply voltage to the motor by inputting a variable width signal to the variable means. If the fan motor stop condition is satisfied even in a condition other than the standby condition, the fan motor control power supply An air conditioner characterized in that the voltage is reduced. The air conditioner according to claim 1, further comprising a rotation speed detection unit that constantly monitors the rotation speed of the fan motor, and the control power of the fan motor is not lowered when the rotation continues due to inertia immediately after the instruction to stop the fan motor.

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