KR101965180B1 - Air conditioner - Google Patents

Abstract

The present invention relates to an air conditioner. An air conditioner according to an embodiment of the present invention includes a first converter for converting an input AC power source to a DC power source and outputting the same, a relay control unit for outputting a relay control signal, and a relay control unit for outputting a relay driving voltage And a relay part having a relay driving part and a voltage dividing part for dividing the relay driving voltage and supplying or cutting off the input AC power to be applied to the first converter based on the divided voltage of the relay driving voltage. Thus, the drive voltage applied to the relay section is divided to reduce the heat generation of the relay coil.

Description

Air conditioner

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an air conditioner, and more particularly, to an air conditioner capable of reducing the heat generation of a relay coil by dividing a driving voltage applied to a relay.

The air conditioner is installed to provide a comfortable indoor environment for humans by discharging cold air to the room to adjust the room temperature and purify the room air to create a pleasant indoor environment.

In the air conditioner, the outdoor unit and the indoor unit are connected to each other through a refrigerant pipe, the refrigerant compressed from the compressor of the outdoor unit is supplied to the heat exchanger of the indoor unit through the refrigerant pipe, and the refrigerant heat-exchanged by the heat exchanger of the indoor unit is again supplied to the outdoor unit And flows into the compressor. Accordingly, the indoor unit discharges the cold air into the room through the heat exchange using the refrigerant.

On the other hand, the air conditioner generally has a relay switch installed at a power input end of an indoor unit or an outdoor unit due to the interruption of standby power or the like. Particularly, relays are advantageous in that they are resistant to overvoltage and overcurrent, are also capable of high frequency control, and are advantageous in cost.

The relay is composed of a relay coil magnetized or demagnetized according to the application of a relay driving voltage and a relay contact which opens or closes a circuit depending on the magnetization of the relay coil or the element.

In particular, the control voltage of the relay coil is standardized to 5V, 12V, 24V, etc., and when the relay control voltage is controlled to be higher than the control voltage, there is a problem that heat generation and power consumption of the relay coil increase.

An object of the present invention is to provide an air conditioner capable of reducing the heat generation of a relay coil by dividing a driving voltage applied to a relay unit.

In order to achieve the above object, an air conditioner according to an embodiment of the present invention includes a first converter for converting an input AC power into a DC power and outputting the same, a relay controller for outputting a relay control signal, And a relay unit for supplying or interrupting an input AC power to be applied to the first converter based on the divided voltage of the relay driving voltage, and a relay unit for outputting a relay driving voltage and a voltage dividing unit for dividing the relay driving voltage .

The air conditioner according to the embodiment of the present invention has an advantage that the heat generation of the relay coil can be reduced by dividing the driving voltage applied to the relay unit.

In addition, the air conditioner can solve the problem that the power consumption of the coil end rises when controlling the relay drive voltage to be higher than the control voltage by dividing the drive voltage applied to the relay part.

Further, since the air conditioner divides the driving voltage applied to the relay unit by using the resistance element, it has an advantage of solving the heat generation problem without changing the product specification of the relay unit.

Conventionally, in the case of an air conditioner, a relay unit using a higher-level control voltage is used in order to solve the heat generation problem. However, since the air conditioner of the present invention does not change the product specification of the relay unit, It is effective.

Also, the high-capacity relay unit product is limited, expensive, and large in size. However, since the air conditioner of the present invention does not change the specification of the relay unit, such a problem can be solved.

Further, the air conditioner may further include a variable resistor, and as the relay driving voltage increases, the resistance value of the variable resistor is set high, so that the heat generation of the relay coil can be easily reduced.

1 is a diagram illustrating a configuration of an air conditioner according to an embodiment of the present invention.
Fig. 2 is a schematic view of the outdoor unit and the indoor unit of Fig. 1. Fig.
3 is a simplified internal block diagram of the air conditioner of Fig.
4 is an internal circuit diagram of the relay unit of Fig.
5 is an example of an internal circuit diagram of an air conditioner according to an embodiment of the present invention.
6 is an example of an internal circuit diagram of an air conditioner according to an embodiment of the present invention.
7 is a diagram referred to in the description of Figs. 5 to 6. Fig.
8 is an example of a circuit diagram of the compressor driving unit of Fig.
Fig. 9 is an internal block diagram of the inverter control unit of Fig. 8; Fig.
10 is an internal block diagram of the converter control section of FIG.
11 is a diagram referred to in the description of the present invention.

Hereinafter, the present invention will be described in detail with reference to the drawings.

The suffix " module " and " part " for components used in the following description are given merely for convenience of description, and do not give special significance or role in themselves. Accordingly, the terms " module " and " part " may be used interchangeably.

Terms including ordinals, such as first, second, etc., may be used to describe various elements, but the elements are not limited to these terms. The terms are used only for the purpose of distinguishing one component from another.

In the present application, the terms "comprises", "having", and the like are used to specify that a feature, a number, a step, an operation, an element, a component, And does not preclude the presence or addition of one or more other features, integers, steps, operations, elements, components, or combinations thereof.

1 is a diagram illustrating a configuration of an air conditioner according to an embodiment of the present invention.

The air conditioner 100 according to the present invention may include an indoor unit 21 and an outdoor unit 31 connected to the indoor unit 21 as shown in FIG.

The indoor unit 21 of the air conditioner may be any of a stand-type air conditioner, a wall-mounted air conditioner, and a ceiling-type air conditioner, but the stand type indoor unit 21 is exemplified in the figure.

Meanwhile, the air conditioner 100 may further include at least one of a ventilator, an air purifier, a humidifier, and a heater, and may operate in conjunction with the operation of the indoor unit and the outdoor unit.

The outdoor unit 31 includes a compressor (not shown) for receiving and compressing the refrigerant, an outdoor heat exchanger (not shown) for exchanging heat between the refrigerant and the outdoor air, an accumulator for extracting the gas refrigerant from the refrigerant supplied to the compressor, And a four-way valve (not shown) for selecting the flow path of the refrigerant according to the heating operation. In addition, a number of sensors, valves, oil recovery devices, and the like are further included, but a description thereof will be omitted below.

The outdoor unit (31) operates the compressor and the outdoor heat exchanger to compress or heat-exchange the refrigerant according to the setting to supply the refrigerant to the indoor unit (21). The outdoor unit (31) can be driven by a demand of a remote controller (not shown) or the indoor unit (21). At this time, as the cooling / heating capacity is changed corresponding to the indoor unit to be driven, the number of operation of the outdoor unit and the number of operation of the compressor installed in the outdoor unit can be varied.

At this time, the outdoor unit (31) supplies the compressed refrigerant to the connected indoor unit (21).

The indoor unit (21) receives the refrigerant from the outdoor unit (31) and discharges cold air to the room. The indoor unit 21 includes an indoor heat exchanger (not shown), an indoor unit fan (not shown), an expansion valve (not shown) in which the supplied refrigerant expands, and a plurality of sensors (not shown).

At this time, the outdoor unit 31 and the indoor unit 21 are connected to each other via a communication line to transmit and receive data, and the outdoor unit and the indoor unit are connected to a remote controller (not shown) by wire or wireless, can do.

A remote controller (not shown) is connected to the indoor unit 21, and inputs a control command of the user to the indoor unit, and receives and displays the status information of the indoor unit. At this time, the remote controller can communicate by wire or wireless according to the connection form with the indoor unit.

Fig. 2 is a schematic view of the outdoor unit and the indoor unit of Fig. 1. Fig.

Referring to the drawings, the air conditioner 100 is roughly divided into an indoor unit 21 and an outdoor unit 31.

The outdoor unit 31 includes a compressor 102 for compressing the refrigerant, a compressor 102b for driving the compressor, an outdoor heat exchanger 104 serving to dissipate the compressed refrigerant, An outdoor fan 105 which is disposed at one side of the heat exchanger 104 and includes an outdoor fan 105a for accelerating the heat radiation of the refrigerant and a motor 250 for rotating the outdoor fan 105a and an outdoor fan 105 for expanding the condensed refrigerant Heating / switching valve or a four-way valve 110 for switching the flow path of the compressed refrigerant, and a controller for temporarily storing the gasified refrigerant to remove moisture and foreign substances, And an accumulator 103 for supplying the exhaust gas.

The indoor unit 21 includes an indoor heat exchanger 109 disposed inside the room and performing a cooling / heating function, an indoor fan 109a disposed at one side of the indoor heat exchanger 109 for promoting heat radiation of the refrigerant, And an indoor air blower 109 composed of an electric motor 109b for rotating the fan 109a.

At least one indoor heat exchanger 109 may be installed. At least one of an inverter compressor and a constant speed compressor may be used as the compressor 102. [

Further, the air conditioner 100 may be constituted by a cooling unit that cools the room, or a heat pump that cools or heats the room.

The outdoor fan 105a in the outdoor unit 31 may be driven by the outdoor fan driving unit 200 that drives the motor 250. [

On the other hand, the compressor 102 in the outdoor unit 31 can be driven by a compressor motor driving unit (113 in Fig. 3) that drives a compressor motor (not shown).

On the other hand, the indoor fan 109a in the outdoor unit 31 can be driven by the indoor fan driving unit 300 that drives the indoor fan motor 109b.

3 is a simplified internal block diagram of the air conditioner of Fig.

3, the air conditioner 100 includes a compressor 102, an outdoor fan 105a, an indoor fan 109a, a controller 170, a discharge temperature sensor 118, an outdoor temperature sensor A sensing unit 138, an indoor temperature sensing unit 158, and a memory 140. The air conditioner 100 includes a compressor driving unit 113, an outdoor fan driving unit 200, an indoor fan driving unit 300, a switching valve 110, an expansion valve 106, a display unit 130, 120).

The compressor 102, the outdoor fan 105a, and the indoor fan 109a are described with reference to FIG.

The input unit 120 includes a plurality of operation buttons, and transmits a signal indicating an operation target temperature of the input air conditioner to the controller 170.

The display unit 130 can display the operation state of the air conditioner 100. [ For example, the display unit 130 may include display means for outputting the operating state of the indoor unit 21, so that the operating state and the error can be displayed.

The display unit 130 may display the connection state of the indoor unit 21 and the outdoor unit 31. [ For example, the display unit 130 may include a light emitting diode (LED), and the light emitting diode (LED) is turned on when the connection state of the communication line and / or the power line is normal, It can be turned off when the connection state of the power line is abnormal.

The memory 140 may store data necessary for the operation of the air conditioner 100.

The discharge temperature sensing unit 118 may sense the refrigerant discharge temperature Tc in the compressor 102 and may transmit a signal regarding the sensed refrigerant discharge temperature Tc to the controller 170. [

The outdoor temperature sensing unit 138 can sense the outdoor temperature To which is the temperature around the outdoor unit 31 of the air conditioner 100 and outputs a signal regarding the sensed outdoor temperature To to the controller 170 ). ≪ / RTI >

The room temperature sensing unit 158 can sense the room temperature Ti which is the temperature around the indoor unit 21 of the air conditioner 100 and transmits a signal regarding the sensed room temperature Ti to the controller 170 ). ≪ / RTI >

The control unit 170 controls the air conditioner 100 based on at least one of the sensed refrigerant discharge temperature Tc, the sensed outdoor temperature To, the sensed room temperature Ti, Can be controlled to operate. For example, the final target superheat degree may be calculated to control the air conditioner 100 to operate.

The control unit 170 controls the operation of the compressor 102, the indoor fan 109a and the outdoor fan 105a by controlling the compressor driving unit 113, the outdoor fan driving unit 200 , And the indoor fan driving unit 300 can be controlled.

For example, the control unit 170 may output a corresponding speed command value signal to the compressor driving unit 113, the outdoor fan driving unit 200, or the indoor fan driving unit 300, respectively, based on the target temperature.

Based on the respective speed command value signals, the compressor motor (not shown), the motor 250, and the indoor fan motor 109b can be operated at the target rotation speed, respectively.

The control unit 170 may control the overall operation of the air conditioner 100 in addition to the control of the compressor driving unit 113, the outdoor fan driving unit 200, and the indoor fan driving unit 300.

For example, the control unit 170 may control the operation of the cooling / heating switching valve or the four-way valve 110. Alternatively, the control unit 170 can control the operation of the expansion mechanism or the expansion valve 106. [

4 is an internal circuit diagram of the relay unit of Fig.

The relay unit 400 includes a relay coil 410 which is magnetized or demagnetized according to the human of the relay drive voltage V2 and a relay coil 410 which is magnetized or de- And a relay contact 430 that opens and closes the circuit according to FIG.

The relay unit 400 can perform an operation of turning on and off the relay contact 430 under the control of the relay control unit 470. The relay control unit 470 will be described in detail with reference to FIG.

The relay contact 430 is spaced apart from the relay coil 410 by a predetermined distance and operates by the magnetic force of the relay coil 410.

For example, when the relay driving voltage V2 is applied to the relay coil 410, the relay coil 410 generates a magnetic force to attract the contact terminal of the relay contact 430, 430).

When the relay driving voltage V2 is not applied to the relay coil 410, the relay coil 410 is depleted in magnetic force to restore the spring contacted relay contact 430 in its original direction, The contact 430 is turned off.

Meanwhile, the relay unit 400 may be set differently depending on the capacity of the air conditioner 100, the purpose of use, and the like.

The specifications of the relay unit 400 can be determined by the manufacturer. For example, the control voltage (rated voltage) of the relay coil 410 may be 12V. Further, the pick-up voltage at which the relay coil 410 is magnetized so as to be in contact with the relay contact 430 may be 70% of the control voltage. In addition, the dropout voltage at which the relay coil 410 is excited and the relay contact 430 is turned off may be 10% of the control voltage.

Hereinafter, the pickup voltage and the dropout voltage may be referred to as an operation voltage of the relay unit 400. [

However, the relay drive voltage V2 is output from the voltage down unit 480, and the relay coil 410 is controlled by the relay coil 410. The control voltage (or the rated voltage) of the relay coil 410 is standardized to 5V, 12V, May not coincide with the control voltage.

At this time, changing the relay drive voltage V2 output from the voltage step-down unit 480 to match the control voltage of the relay unit 400 leads to a large loss in cost.

Further, when the relay control voltage is controlled to be higher than the control voltage of the relay unit 400, there is a problem that the heat generation and power consumption of the relay coil 410 increases.

As a solution to this problem, the present invention reduces the magnitude of the voltage applied to the relay coil 410 by connecting a resistance component for dividing the relay driving voltage V2 to the relay coil 410 in series, 400 and the power consumption of the power source.

4, the relay unit 400 may further include a voltage dividing unit 420 that divides the relay driving voltage V2. The division unit 420 may include a resistance component. The resistance component may be, for example, a resistance element or a variable resistance. In the following description, the dividing portion 420 and the resistance component may be used in combination.

The division unit 420 may be a resistance element or a variable resistor. The resistance element or the variable resistor may be connected in series to the relay coil 410. [

The relay driving voltage V2 can be divided by the resistance component connected in series to the relay coil 410 and the divided relay driving voltage can be applied to the relay coil 410. [

The relay coil 410 generates a magnetic force so as to attract the contact terminal of the relay contact 430 so that the relay contact 430 is turned on .

On the other hand, the resistance magnitude of the resistance component can be set in consideration of the divided voltage of the relay driving voltage and the control voltage of the relay unit 400.

For example, the divided relay driving voltage may be equal to or greater than the control voltage of the relay unit 400, and the resistance magnitude of the resistance component 420 may be set in consideration thereof.

At this time, the memory 140 of the air conditioner can store information on the threshold value of the relay sub control voltage necessary to turn on the relay contact 430. [ Also, the memory 140 may store information on the threshold value of the control current of the relay unit 400, the relay driving voltage V2, and the divided voltage of the relay driving voltage.

When the relay driving voltage is not applied to the relay coil 410, the relay coil 410 is depleted in magnetic force to restore the spring-structured relay contact 430 in the original direction, and thereby the relay contact 430 Can be turned off.

On the other hand, the resistance component 420 may be a resistance element. As for the resistance element, the larger the relay driving voltage, the larger the resistance value can be used.

For example, when the relay driving voltage is the first level voltage LV1 and the relay driving voltage is larger than the first level voltage LV1, the second level voltage LV2, , A second resistive element R2 that is larger than the first resistive element R1 may be used.

That is, the larger the relay driving voltage V2, the greater the resistance value of the resistance element. As the resistance value of the resistance element increases, the voltage applied to the resistance element becomes larger, , The magnitude of the voltage of the divided relay drive voltage can be reduced.

Therefore, it is possible to solve the heat generation problem of the relay unit 400 in addition to the resistance element and the like, without changing the specification of the relay part product.

The resistance component 420 may be a variable resistor. The variable resistor can be variably set in proportion to the relay drive voltage V2. That is, the larger the relay driving voltage, the larger the resistance value can be set.

For example, when the relay driving voltage is the third level voltage LV3, when the variable resistance is set to the first resistance size, the relay driving voltage is lower than the fourth level voltage (LV3) LV4), the variable resistance can be set to a second resistance size larger than the first resistance size.

In the relay unit 400, a diode D for preventing reverse current flow may be connected in parallel with the relay coil 410 and the resistance component 420.

More specifically, in a state where the relay coil 410 and the resistance component 420 are connected in series, the cathode of the diode D is connected to one end of the resistance component 420, And may be connected to one end of the coil 410.

On the other hand, an inrush current preventing resistor (not shown) for preventing an inrush current may be connected to the relay contact 430 in parallel.

5 is an example of an internal circuit diagram of an air conditioner according to an embodiment of the present invention.

Referring to the drawings, an air conditioner 100 according to an embodiment of the present invention includes a relay control unit 470 for outputting a relay control signal, a relay driving unit 460 for outputting a relay driving voltage based on a relay control signal A relay unit 400 for interrupting the input AC power supply 201, a first converter 440 for converting AC power to DC power, a second converter 450, an inverter 220 for converting DC power to AC power ). ≪ / RTI >

5 illustrates that the relay control unit 470, the relay driving unit 460, and the relay unit 400 are disposed in the outdoor unit 31. FIG.

The relay unit 400 may be connected between the input AC power supply 201 and the first converter 440. The relay unit 400 includes a voltage dividing unit 420 that divides the relay driving voltage and supplies the input AC power 201 to the first converter 440 based on the divided voltage of the relay driving voltage Or block.

More specifically, the relay unit 400 includes a relay coil 410 that is magnetized or elected based on the divided voltage of the relay driving voltage, a relay contact that is opened or closed by the relay coil to supply or block the input AC power source 201, (Not shown).

Further, the voltage dividing section 420 may be connected in series to the relay coil 410. [ The division unit 420 may be a resistance element or a variable resistor as described above.

The relay unit 400 may further include a diode element D connected in parallel with the relay coil 410 and the voltage dividing unit 420. The diode element D is used to prevent a reverse current applied to the relay unit 400. [

The relay driving part 460 can receive the direct current relay driving voltage V2 from the voltage down converting part 480 described later. The relay driving unit 460 can output the relay driving voltage V2 to the relay unit 400. [

More specifically, the relay driver 460 may include at least one switching element, and may turn on / off the switching element in response to the relay control signal. The relay driving voltage V2 can be applied to the relay unit 400 by the turn-on / off operation of the switching element. The switching element may be a transistor element.

For example, the relay driver 460 may be configured to include two transistors connected to Darlington.

The relay control unit 470 can output a relay control signal for controlling the relay unit 400. [

For example, the outdoor unit 31 may further include an outdoor unit communication unit (not shown) communicating with an indoor unit communication unit (not shown), and the indoor unit 21 may transmit a control signal to the outdoor unit 31 Lt; / RTI > To this end, the indoor unit communication unit (not shown) and the outdoor unit communication unit (not shown) may include at least any one of the communication modules.

When the user's operation command is a power-off command, the indoor unit 21 can transmit a control signal corresponding to the power-off command to the outdoor unit 31. [ The outdoor unit 31 can receive the control signal corresponding to the power-off command.

The relay control unit 470 can output the relay control signal based on the control signal corresponding to the power off command. For example, the relay control signal corresponding to the power off command may be a low ('low', '0') signal.

The relay driver 460 may include at least one switching element and may turn off the switching element in response to a low ('low', '0') signal of the relay controller 470.

The relay drive voltage V2 can not be applied to the relay unit 400 due to the turn-off operation of the switching element and the relay coil 410 can not be pulled to attract the contact terminal of the relay contact 430 . Therefore, the relay contact 430 is turned off.

Accordingly, when the commercial AC power source is connected to the power supply line but the outdoor unit is not operated, the relay unit 400 can control the load of the first converter 440, the inverter 220, the motor 250, And the power consumption is reduced.

When the user's operation command is a power-on command, the indoor unit 21 can transmit a control signal corresponding to the power-on command to the outdoor unit 31. [ The outdoor unit (31) can receive the control signal corresponding to the power on command.

The relay control unit 470 can output the relay control signal based on the control signal corresponding to the power on command. For example, the relay control signal corresponding to the power on command may be a high ('high', '1') signal.

The relay driving unit 460 can output the relay driving voltage based on the relay control signal.

For example, the relay driver 460 may include at least one switching element and may turn on the switching element corresponding to high ('high', '1') of the relay controller 470 .

The relay driving voltage V2 can be applied to the relay unit 400 by the turn-on operation of the switching element.

The relay unit 400 may further include a voltage dividing unit 420 connected in series to the relay coil 410 to divide the relay driving voltage V2, A voltage may be applied to the relay coil 410.

When the relay coil 410 is applied with the divided relay driving voltage higher than the operating voltage, the relay coil 410 is magnetized to pull the contact terminal of the relay contact 430. Accordingly, the relay contact 430 is turned on.

When the relay contact 430 is turned on, the air conditioner 100 cancels the standby mode and performs various functions in response to a user's operation command.

When the relay unit 400 is controlled by the relay drive voltage V2 higher than the rated voltage of the relay unit 400 by dividing the relay drive voltage V2 applied to the relay unit 400, It is possible to solve the heat generation problem of the relay coil 410 which is formed by the relay coil 410. Also, the power consumption of the relay coil 410 can be reduced.

On the other hand, the voltage divider 420 may be a resistance element, a variable resistor, or the like. When the resistance component 420 is a resistance element, the resistance element can be designed as an element having a larger resistance value as the relay driving voltage V2 is larger.

Further, when the resistance component 420 is a variable resistor, the variable resistor can be variably set in proportion to the relay drive voltage V2. That is, the larger the relay driving voltage V2, the larger the resistance value can be set. This will be described in more detail in Fig.

Thereby, there is an advantage that the heat generation of the relay coil 410 can be easily reduced according to the setting of the variable resistor or the replacement of the resistance element without changing the specification of the product.

Hereinafter, the relay control unit 470 may be the control unit 170 of FIG. The relay control unit 470 may be the converter control unit 215 of Fig. In addition, the relay control unit 370 may be the inverter control unit 230 of Figs.

3 may perform not only the overall operation of the air conditioner 100 but also the functions of the relay unit 400, the converter 210, and the inverter 220.

The first converter 440 can convert the input AC power supply 201 to DC power and output it. In the figure, the commercial AC power source 201 is shown as a single-phase AC power source, but it may be a three-phase AC power source. The internal structure of the first converter 440 is also changed depending on the type of the commercial AC power source 201.

The first smoothing capacitor C1 is connected to the output terminal of the first converter 440 so that the converted DC power outputted from the first converter 440 is smoothed. On the other hand, the first smoothing capacitor C1 may be called a dc-step capacitor corresponding to the voltage-drop capacitor C2.

Hereinafter, the output terminal of the first converter 440 is referred to as a dc stage or a dc link stage. A smoothed DC voltage on the dc stage is applied to the inverter 220.

The first converter 440 may include only a rectification section, or may include a rectification section and a switching element.

The rectification section can receive the single-phase AC power source 201, rectify it, and output the rectified power.

To this end, the rectifying part is a pair of the upper-arm diode element and the lower-arm diode element (D'a, D'b) connected in series to each other, and two pairs of upper and lower arm diode elements can be connected in parallel to each other. That is, they can be connected to each other in the form of a bridge.

When the rectifying section is a three-phase AC power source, six diodes may be used in the form of a bridge.

The inverter 220 includes a plurality of inverter switching elements, and can convert the smoothed direct current power into a three-phase alternating current power having a predetermined frequency by the on / off operation of the switching element, and output it to the three-phase motor 250.

The inverter 220 includes a pair of upper arm switching elements Sa, Sb and Sc and lower arm switching elements S'a, S'b and S'c connected in series to each other, The switching elements are connected to each other in parallel (Sa & S a, Sb & S'b, Sc & S'c). Diodes are connected in anti-parallel to each switching element Sa, S'a, Sb, S'b, Sc, S'c.

The switching elements in the inverter 220 perform ON / OFF operations of the respective switching elements based on the inverter switching control signal Sic from the inverter controller 230. [ Thereby, the three-phase AC power source having the predetermined frequency is outputted to the three-phase synchronous motor 250.

The inverter control unit 230 will be described in detail with reference to FIG.

The second converter 450 can convert the input AC power supply 201 to DC power and output it. In the figure, the commercial AC power source 201 is shown as a single-phase AC power source, but it may be a three-phase AC power source. The internal structure of the second converter 450 also changes depending on the type of the commercial AC power source 201. [

Meanwhile, the second converter 450 may be connected in parallel with the first converter 440 at the front end of the relay unit 400. The relay unit 400 blocks only the voltage applied to the first converter 440 so that the power applied to the voltage down unit 480 through the second converter 450 is level- (Not shown).

The second smoothing capacitor C2 is connected to the output terminal of the second converter 450 so that the converted DC power outputted from the second converter 450 is smoothed. The smoothed DC voltage across the second smoothing capacitor C2 is applied to the voltage down unit 480. The second smoothing capacitor C2 may be referred to as a voltage-falling capacitor C2 in contrast to the dc-side capacitor C1.

The voltage step-down unit 480 receives a smoothed DC voltage and can output a DC voltage for driving a circuit, a unit, and the like constituting the outdoor unit 31. [

More specifically, the voltage step-down unit 480 is connected to both ends of the voltage step-down capacitor C2 to output a level-changed direct-current voltage. For example, the level-changed DC voltage may be 15V, 18V, 20V, and the like.

The voltage step-down unit 480 can supply the first DC voltage V1 to the relay control unit. The first DC voltage V1 may be stored in the capacitor and supplied to the relay control unit 470. [

The voltage step-down unit 480 can supply the second direct-current voltage V2 to the relay driver 460. [ The second DC voltage V2 may be stored in the capacitor and supplied to the relay driver 460. In particular, the second direct current voltage V2 can be called a relay driving voltage V2. On the other hand, the second DC voltage V2 is preferably larger than the first DC voltage V1.

The voltage down converter 480 may include an AC-to-DC converter such as a Switched-Mode Power Supply (SMPS) using a high-frequency transformer or a buck converter of a non-insulation step-down type .

On the other hand, the relay driving part 460 includes at least any one switching element, and on the basis of the relay control signal, the relay driving part 460 can turn on / off the switching element and output the relay driving voltage V2 to the relay part 400 have.

6 is an example of an internal circuit diagram of an air conditioner according to an embodiment of the present invention.

Differences from FIG. 6 are the voltage dividing portion 420 and the divided voltage detecting portion F. FIG. Hereinafter, the same components as those in FIG. 5 are denoted by the same reference numerals, and a description thereof will be omitted.

The voltage divider 420 may be a variable resistor. At this time, the relay control unit 470 can output to the relay unit 400 the resistance control signal R ^* that controls the resistance value of the variable resistor to become larger as the relay driving voltage V2 becomes larger. The variable resistance can be variably set based on the resistance control signal R ^* .

On the other hand, the memory 140 may store information on a threshold value of the operation voltage required to turn on the relay unit 400, and the relay control unit 470 may control the relay unit 400 based on the information on the threshold value, (R ^* ) can be output. Thus, the variable resistor can be set to an appropriate resistance value in consideration of the minimum value of the operating voltage.

The air conditioner 100 according to the embodiment of the present invention may further include a divided voltage detection unit F for detecting a divided voltage of the relay coil 410. [

The divided voltage detecting unit F can detect the divided voltage applied to the relay coil 410 by being divided by the voltage dividing unit 420. Further, the information Vdiv about the divided voltage may be transmitted to the relay control unit.

The relay control unit 470 can calculate the power consumption of the relay coil 410 based on the divided voltage. In addition, the resistance value of the variable resistor for driving the relay coil 410 with minimum power can be calculated in consideration of the information on the threshold value of the operating voltage.

The relay control unit 470 can output the resistance control signal R ^* to the relay unit 400 based on the information on the resistance value of the variable resistor. Therefore, the resistance control signal R ^* may include information on the resistance value of the variable resistor.

On the other hand, the variable resistor can be variably set based on the resistance control signal R ^* . Accordingly, the relay unit 400 can be driven with the optimum variable resistance value while considering the power consumption of the relay coil 410.

Generally, the heat generated by the relay unit 400 is generated by the relay coil 410. Since the heat generated by the relay unit 400 is related to the power consumption of the relay coil 410, Also, there is an advantage that the problem of heat generation can be solved only by setting the variable resistance.

FIG. 7 is a diagram referred to in the description of FIGS. 5 to 6. FIG.

Referring to the drawings, in the air conditioner 100, the relay unit 400 is selected in accordance with the relay driving voltage V2 output from the voltage step-down unit 480 of the air conditioner 100 It is common to lose.

However, it is rare that the relay driving voltage V2 output from the voltage down unit 480 of the air conditioner 100 coincides with the control voltage (rated voltage) of the relay unit 400, Adjusting the output of the voltage down converter 480 according to the specification of the product is time-consuming and expensive.

In addition, when the relay control voltage is controlled to be higher than the control voltage, there is a problem that the heat generation and power consumption of the relay coil 410 increases.

To solve this problem, the present invention reduces the heat generation and power consumption of the relay coil 410 by connecting a resistance component to the relay coil 410 in series.

7 is a table showing the power consumption of the relay coil 410 in accordance with the relay drive voltage and the resistance value of the resistance component 420. FIG.

The control voltage and the resistance value of the relay coil 410 may be a predetermined value by the manufacturer of the relay unit 400.

For example, in FIG. 6, the control voltage of the relay coil 410 is 12V, and the resistance value of the relay coil 410 may be 160 ohms.

The drop-out voltage at which the pickup voltage forming the contact with the relay contact 430 is 70% of the control voltage and the relay coil 410 is excited so that the relay contact 430 is off may be 10% of the control voltage .

7, when the relay driving voltage V2 is 15V and the resistance component 420 is not connected in series, the relay driving voltage V2 of 15V can be all applied to the relay coil 410. [ At this time, the power consumption of the relay coil 410 may be 1.41W.

On the other hand, when the resistance component 420 of 40.2 ohms is connected in series to the relay coil 410, the relay driving voltage V2 of 15 V can be divided by the resistance component 420. [ Therefore, 3.01 V is applied to the resistance component 420 and 11.99 V to the relay coil 410 according to the principle of voltage distribution. At this time, the power consumption of the relay coil 410 may be 0.90W.

When the resistance component 420 of 60 ohms is connected in series to the relay coil 410, 4.09 V is applied to the resistance component 420 and 10.91 V can be applied to the relay coil 410. At this time, the power consumption of the relay coil 410 may be 0.74W.

When the relay driving voltage V2 is 20V and the resistance component 420 is not connected in series, the relay driving voltage V2 of 20V may be applied to the relay coil 410. [ At this time, the power consumption of the relay coil 410 may be 2.50W.

On the other hand, when the resistance element 420 of 107 ohms is connected in series to the relay coil 410, the relay driving voltage V2 of 20 V can be divided by the resistance component 420. Therefore, 3.01 V is applied to the resistance component 420 and 11.99 W is applied to the relay coil 410 according to the voltage distribution principle. At this time, the power consumption of the relay coil 410 may be 0.90W.

Also, when the resistance component 420 of 133 ohms is connected in series to the relay coil 410, 4.08 V is applied to the resistance component 420 and 10.92 V can be applied to the relay coil 410. At this time, the power consumption of the relay coil 410 may be 0.75W.

When the relay driving voltage V2 is 15 V and 20 V, the power consumption is 1.41 W and 2.50 W, respectively, when there is no resistance component 420. That is, when the relay unit 400 is controlled to a relay driving voltage V2 higher than the control voltage 12V, it is understood that the power consumption of the relay coil 410 is increased. As a result, the heat generation of the relay coil 410 also increases.

However, as shown in FIGS. 5 to 6, the power consumption of the relay coil 410 can be set to the same level by connecting the voltage divider 420 to the relay coil 410 in series.

Accordingly, the heat generation problem of the relay coil 410 can be solved without changing the specification of the product of the relay unit 400 or the output of the voltage down unit 480. [

 On the other hand, as described above, the voltage division unit 420 may be a resistance element, a variable resistor, or the like.

When the voltage divider 420 is a resistor element, the larger the relay drive voltage V2, the larger the resistance value can be designed. Further, the resistance element can be designed in consideration of the threshold value of the operation voltage for turning on the relay contact 430. [

7, it can be seen that the resistance value of the resistance element of the voltage divider 420 is larger when the relay driving voltage V2 is 20V than when the relay driving voltage V2 is 15V.

On the other hand, it can be seen that the minimum operating voltage of the relay unit 400 is 10.8 V in consideration of the dropout voltage (for example, 10% of the control voltage). Therefore, it is preferable to use a resistance element of 133 ohms when the relay driving voltage V2 is 60 V, and the relay driving voltage V2 is 20 V when the relay driving voltage V2 is 15 V, considering the minimum operating voltage of the resistance element.

When the resistance component 420 is a variable resistor, the variable resistor can be variably set so that the resistance value becomes larger the larger the relay drive voltage V2.

More specifically, the relay control unit 470 can output to the relay unit 400 a resistance control signal R ^* that controls the variable resistance value to become larger as the relay driving voltage V2 becomes larger. The variable resistor may be variably set based on the resistance control signal R ^* .

Meanwhile, the memory 140 may store information on a threshold value of the operation voltage necessary for operating the relay unit 400, and the relay control unit 470 may control the operation of the relay unit 400 based on the information on the threshold value, (R ^* ) can be output. Thus, the variable resistor can be set to an appropriate resistance value in consideration of the minimum value of the operating voltage.

For example, in FIG. 7, the memory 140 may store 10.8 V, which is the minimum value of the operating voltage, and when the relay driving voltage V2 is 20 V than when the relay driving voltage V2 is 15 V, And outputs the resistance control signal R ^* to the relay unit 400 so as to increase the value of the resistance control signal R ^* .

At this time, the resistance control signal R ^* may include information about a resistance value of 133 ohms in consideration of 10.8 V, which is the minimum operation voltage of the relay unit 400. Further, the variable resistor can be variably set to 133 ohms based on the resistance control signal R ^* .

8 is an example of a circuit diagram of the compressor driving unit of Fig.

The compressor driving unit 113 includes an inverter 220 for outputting a three-phase AC current to the compressor motor 250, an inverter control unit 230 for controlling the inverter 220, an inverter 220, A converter control unit 215 for controlling the converter 210 and a dc capacitor C between the converter 210 and the inverter 220. [

The compressor driving unit 113 may further include a dc voltage detection unit B, an input voltage detection unit A, an input current detection unit D, and an output current detection unit E.

The compressor driving unit 113 receives the AC power from the system, converts the power, and supplies the converted power to the motor 250. Accordingly, the compressor driving unit 113 may be referred to as a power conversion apparatus.

The converter 210 converts the input AC power supply to DC power supply. The converter 210 may include only a rectifying part (not shown), or may include a rectifying part and a switching element.

The rectifying unit (not shown) can rectify the received single-phase AC power source 201 and output rectified power.

To this end, the rectifying part (not shown) is composed of a pair of upper and lower arm diode elements D'a and D'b connected in series to each other, and two pairs of upper and lower arm diode elements are connected in parallel to each other . That is, they can be connected to each other in the form of a bridge.

On the other hand, when the converter 210 includes a switching element, for example, a boost converter may be provided. That is, an inductor and a diode connected in series with each other, and a switching element connected between the inductor and the diode may be provided between the rectifying part (not shown) and the inverter 220. [

The converter control unit 215 can control the turn-on timing of the switching element when the converter has a switching element. Thus, the converter switching control signal Soc for turning-on timing of the switching element can be output.

To this end, the converter control unit 215 can receive the input voltage Vs and the input current Is from the input voltage detection unit A and the input current detection unit D, respectively.

The input voltage detecting section A can detect the input voltage Vs from the input AC power supply 201. [ For example, at the front end of the rectifying part (not shown).

The input voltage detecting unit A may include a resistance element, an OP AMP, or the like for voltage detection. The detected input voltage Vs can be applied to the converter control unit 215 to generate a converter switching control signal Soc as a discrete signal in the form of a pulse.

On the other hand, the input voltage detecting section A can also detect the zero crossing point of the input voltage.

Next, the input current detection section D can detect the input current Is from the input AC power source 201. [ Specifically, it can be positioned at the front end of the rectifying section (not shown).

The input current detection unit D may include a current sensor, a current transformer (CT), a shunt resistor, or the like, for current detection. The detected input voltage can be applied to the converter control unit 215 for generation of the converter switching control signal Scc as a discrete signal in the form of a pulse.

The dc voltage detecting section B detects the dc voltage Vdc of the dc short-circuit capacitor C. For power detection, a resistance element, OP AMP, or the like can be used. The detected voltage Vdc of the dc short-circuit capacitor C may be applied to the inverter control unit 230 as a discrete signal in the form of a pulse and may be supplied to the DC voltage Vdc of the dc- The inverter switching control signal Sic can be generated.

Further, the detected dc voltage is applied to the converter control unit 215, and the converter switching control signal Soc may be used for generation.

The inverter 220 includes a plurality of inverter switching elements and converts the smoothed direct current power supply Vdc into a three-phase alternating current power having a predetermined frequency by the on / off operation of the switching element, .

Accordingly, the inverter 220 can supply the inverter power to the motor 250 as a load. The inverter power at this time can follow the required target power as the power required by the motor 250 as the load.

More specifically, the inverter 220 may include a plurality of switching elements. For example, the upper arm switching elements Sa, Sb, Sc and the lower arm switching elements S'a, S'b, S'c are connected in series to each other and a total of three pairs of upper and lower arm switching elements Can be connected to each other in parallel (Sa & S'a, Sb & S'b, Sc & S'c). Diodes may be connected in anti-parallel to each switching element Sa, S'a, Sb, S'b, Sc, S'c.

The inverter control unit 230 can output the inverter switching control signal Sic to the inverter 220 in order to control the switching operation of the inverter 220. [ The inverter switching control signal Sic is a switching control signal of the pulse width modulation method PWM and is based on the output current io which is a three-phase current flowing to the motor 250 and the dc voltage Vdc across the dc- , And can be generated and output. The three-phase output current io at this time can be detected from the output current detection section E and the dc short voltage Vdc can be detected from the dc short voltage detection section B. [

The output current detection section E can detect the output current io flowing between the inverter 220 and the motor 250. [ That is, the current flowing in the motor 250 is detected. The output current detection unit E can detect all of the output currents ia, ib, ic of each phase or can detect the output currents of two phases using the three-phase balance.

The output current detector E may be located between the inverter 220 and the motor 250. For current detection, a current transformer (CT), a shunt resistor, or the like may be used.

On the other hand, the output inverter switching control signal Sic can be converted into a gate driving signal in a gate driver (not shown) and input to the gate of each switching element in the inverter 220. As a result, the switching elements Sa, S'a, Sb, S'b, Sc, and S'c in the inverter 220 perform the switching operation.

On the other hand, the converter 210 of Fig. 8 may correspond to the first converter 440 of Figs. 5 to 6.

Fig. 9 is an internal block diagram of the inverter control unit of Fig. 8; Fig.

The inverter control unit 230 includes an axis conversion unit 310, a speed calculation unit 320, a current command generation unit 330, a voltage command generation unit 340, an axis conversion unit 350, And a switching control signal output unit 360.

The axial conversion unit 310 receives the three-phase output currents ia, ib, ic detected by the output current detection unit E and converts the three-phase output currents ia, ib, ic into the two-phase currents iα, iβ in the stationary coordinate system.

On the other hand, the axis converting unit 310 can convert the two-phase current i ?, i? Of the still coordinate system into the two-phase current id, iq of the rotating coordinate system.

)와 연산된 속도(

)를 출력할 수 있다.Based on the two-phase current (i?, I?) Of the stationary coordinate system changed in the axis by the axis converting unit 310, the speed calculating unit 320 calculates the speed

) And the calculated speed (

Can be output.

)와 속도 지령치(ω^* _r)에 기초하여, 전류 지령치(i^* _q)를 생성한다. 예를 들어, 전류 지령 생성부(330)는, 연산 속도(

)와 속도 지령치(ω^* _r)의 차이에 기초하여, PI 제어기(335)에서 PI 제어를 수행하며, 전류 지령치(i^* _q)를 생성할 수 있다. 도면에서는, 전류 지령치로, q축 전류 지령치(i^* _q)를 예시하나, 도면과 달리, d축 전류 지령치(i^* _d)를 함께 생성하는 것도 가능하다. 한편, d축 전류 지령치(i^* _d)의 값은 0으로 설정될 수도 있다. On the other hand, the current command generation unit 330 generates the current command

(I ^* _q ) on the basis of the speed command value? ^* _R and the speed command value? ^* _R. For example, the current command generation section 330 generates the current command

The PI controller 335 performs the PI control based on the difference between the speed command value? ^* _R and the speed command value? ^* _R , and generates the current command value i ^* _q . In the figure, the q-axis current command value (i ^* _q ) is exemplified by the current command value, but it is also possible to generate the d-axis current command value (i ^* _d ) unlike the figure. On the other hand, the value of the d-axis current command value i ^* _d may be set to zero.

On the other hand, the current command generation section 330 may further include a limiter (not shown) for limiting the current command value (i ^* _q ) so that the current command value (i ^* _q ) does not exceed the allowable range.

Next, the voltage command generating unit 340 generates the voltage command generating unit 340 with the d-axis and q-axis currents (i _d , i _q ) axially transformed into the two-phase rotational coordinate system in the axial converting unit and the current command value based on ^{_{i * d, i * q)}} , and generates a d-axis, q-axis voltage command value ^{_{(v * d, v * q}} ). For example, the voltage command generation unit 340 performs PI control in the PI controller 344 based on the difference between the q-axis current (i _q ) and the q-axis current command value (i ^* _q ) It is possible to generate the axial voltage command value v ^* _q . The voltage command generation unit 340 performs PI control in the PI controller 348 based on the difference between the d-axis current i _d and the d-axis current command value i ^* _d , It is possible to generate the command value v ^* _d . The voltage command generator 340 may further include a limiter (not shown) for limiting the level of the d-axis and q-axis voltage command values v ^* _d and v ^* _q so as not to exceed the permissible range .

On the other hand, the generated d-axis and q-axis voltage command values (v ^* _d and v ^* _q ) are input to the axial conversion unit 350.

)와, d축, q축 전압 지령치(v^* _d,v^* _q)를 입력받아, 축변환을 수행한다.The axis transforming unit 350 transforms the position calculated by the velocity calculating unit 320

) And the d-axis and q-axis voltage command values (v ^* _d , v ^* _q ).

)가 사용될 수 있다.First, the axis converting unit 350 performs conversion from a two-phase rotating coordinate system to a two-phase stationary coordinate system. At this time, the position calculated by the speed calculator 320 (

) Can be used.

Then, the axial conversion unit 350 performs conversion from the two-phase stationary coordinate system to the three-phase stationary coordinate system. Through this conversion, the axial conversion unit 1050 outputs the three-phase output voltage instruction values v ^* a, v ^* b, v ^* c.

The switching control signal output section 360 generates the switching control signal Sic for inverter according to the pulse width modulation (PWM) method based on the three-phase output voltage instruction values v ^* a, v ^* b and v ^* And outputs it.

The output inverter switching control signal Sic may be converted into a gate driving signal in a gate driver (not shown) and input to the gate of each switching element in the inverter 220. [ As a result, the switching elements Sa, S'a, Sb, S'b, Sc, and S'c in the inverter 220 perform the switching operation.

10 is an internal block diagram of the converter control section of FIG.

The converter control unit 215 may include a current command generation unit 910, a voltage command generation unit 920, and a switching control signal output unit 930.

Based on the dc terminal voltage Vdc and the dc terminal voltage command value V ^* dc detected by the output voltage detecting section B, that is, the dc terminal voltage detecting section B, the current command generating section 910 generates a current command The q-axis current command value (i ^* _d , i ^* _q ) can be generated.

The voltage command generation section 920 generates d and q commands via a PI controller based on the d and q axis current command values i ^* _d and i ^* _q and the input current is detected by the input current detection section A, Axis voltage command value (v ^* _d , v ^* _q ).

The switching control signal output unit 930 outputs a converter switching control signal Soc for driving the switching elements in the converter 210 of Fig. 7 based on the d, q-axis voltage instruction values v ^* _d and v ^* _q Converter 210 as shown in FIG.

11 is a drawing referred to in the description of the present invention.

10 is an explanatory view showing a state in which the input AC power supply 201 is drawn through the indoor unit 21 and supplied with AC power to the outdoor unit through a power line connected to the outdoor unit 31, Fig.

Hereinafter, the same constituent elements as those of FIG. 5 are denoted by the same reference numerals, and a description thereof will be omitted.

The relay unit 400 can be connected between the input AC power supply 201 of the indoor unit 21 and the rectifying unit 1010. [

That is, in the indoor lead-in type, the relay unit 400 can control the AC power applied to the outdoor unit 31 by being connected to the indoor unit 21.

The relay unit 400 includes a resistance component 420 for dividing the relay driving voltage and can control the AC power supply 201 applied to the rectifying unit 1010 based on the divided relay driving voltage V3 have.

At this time, the relay driving voltage V3 may be supplied by the voltage down converter 1030 in the indoor unit 21. [

The relay unit 400 may further include a resistance element 430a (inrush current limiting resistance element) for preventing an inrush current drawn into the outdoor unit 31. [ The resistance element 430a may be connected to the relay contact 430 in parallel.

On the other hand, it is preferable that the resistance value of the resistance element 430a for preventing the inrush current is set to be larger than the resistance value of the voltage divider 420.

11, the relay control unit 470 turns off the relay contact 430 in the initial operation to prevent the inrush current from flowing into the outdoor unit 31 so that the input AC power is applied to the outdoor unit 31 can do.

After a predetermined time, the relay control unit 470 can turn on the relay contact 430 so that the input AC power source 201 is applied to the outdoor unit 31 through the relay contact 430.

The rectifying unit 1010 can receive the single-phase AC power source 201 and rectify it, and output the rectified power to the voltage drop capacitor.

To this end, the rectifying part is a pair of the upper-arm diode element and the lower-arm diode element (D'a, D'b) connected in series to each other, and two pairs of upper and lower arm diode elements can be connected in parallel to each other. That is, they can be connected to each other in the form of a bridge.

When the rectifying section is a three-phase AC power source, six diodes may be used in the form of a bridge.

The voltage down converter 1030 in the indoor unit 21 can receive a smoothed direct current voltage and can output a direct current voltage for driving a circuit, a unit, etc. constituting the indoor unit 21. [

More specifically, the voltage downpressure unit 1030 in the indoor unit 21 can be connected to both ends of the voltage down converting capacitor to output a DC voltage having a level changed. For example, the level-changed DC voltage may be 15V, 18V, 20V, and the like.

The voltage down converter 1030 in the indoor unit 21 can supply the third DC voltage V3 to the relay controller 470. [

The voltage down converter 1030 in the indoor unit 21 can supply the fourth direct current voltage V4 to the relay driver 460. [ In particular, the fourth direct-current voltage V4 can be referred to as a relay drive voltage V4. The fourth direct-current voltage V4 is preferably larger than the third direct-current voltage V3.

The voltage down converter 1030 in the indoor unit 21 may be an AC-DC converter such as a Switched-Mode Power Supply (SMPS) using a high-frequency transformer or a buck converter of a non- . ≪ / RTI >

Meanwhile, the air conditioner 100 may further include a fuse (not shown) between the input AC power source 201 and the relay unit 400.

The fuse (not shown) is disposed at the front end of the relay unit 400 to prevent the overcurrent from being applied to the indoor unit 21 and the outdoor unit 31.

The indoor unit 21 may further include a first AC power supply terminal L1 and a first neutral terminal N1 and the outdoor unit 31 may include a first AC power supply terminal L1 and a first neutral terminal N1, A second AC power supply terminal L2 and a second neutral terminal N2 which are connected to each other.

The input AC power supply 201 can be applied to the outdoor unit 31 through the power supply line. The applied AC power may be applied to the voltage down converter 480 through the second converter 450. The voltage step-down unit can output the level-changed DC voltage.

The voltage step-down unit 480 can output the level-changed DC voltage to the outdoor unit control unit 1070. The overall operation of the outdoor unit 31 of the outdoor unit control unit 1070 can be controlled.

Further, the voltage step-down unit 480 can output the level-changed DC voltage to the outdoor unit load unit 1050. [ The outdoor unit load unit 1050 may include a fan driving unit 200, a motor, a fan, and the like included in the outdoor unit 31 for driving the outdoor fan 105a, It can be driven by the receiving DC voltage.

5, the relay unit 400, the relay driving unit 460, and the relay control unit 470 may be connected between the second AC power terminal and the second neutral terminal and the first converter 440 .

It is to be understood that both the foregoing general description and the following detailed description are exemplary and explanatory and are intended to provide further explanation of the invention as claimed. It should be understood that it includes water and alternatives.

Likewise, although the operations are depicted in the drawings in a particular order, it should be understood that such operations must be performed in that particular order or sequential order shown to obtain the desired result, or that all depicted operations should be performed . In certain cases, multitasking and parallel processing may be advantageous.

While the present invention has been particularly shown and described with reference to exemplary embodiments thereof, it is to be understood that the invention is not limited to the disclosed exemplary embodiments, but, on the contrary, It should be understood that various modifications may be made by those skilled in the art without departing from the spirit and scope of the present invention.

21: indoor unit
31: outdoor unit
100: air conditioner
220: Inverter
400: relay part
410: Relay coil
420: Resistance component
430: Relay contact
440: First converter
450: second converter
460:
470: Relay control unit
480:

Claims (10)

A first converter for converting the input AC power into DC power and outputting the DC power;
A relay control unit for outputting a relay control signal;
A relay driver for outputting a relay driving voltage based on the relay control signal;
A relay unit having a voltage dividing unit for dividing the relay driving voltage and supplying or blocking the input AC power to the first converter based on the divided voltage of the relay driving voltage; And
And a divided voltage detecting unit,
The relay unit includes:
A relay coil which is magnetized or excited based on the divided voltage of the relay driving voltage; and a relay contact which is opened or closed by the relay coil to supply or block the input AC power,
The pressure-
A variable resistor connected in series to the relay coil,
Wherein the divided voltage detecting unit comprises:
A voltage dividing unit for dividing the voltage applied to the relay coil,
The relay control unit,
Calculating a power consumption of the relay coil based on the divided voltage, calculating a power consumption of the relay coil for driving the relay coil to a minimum power in consideration of information on a threshold value of an operating voltage for turning on the relay contact Calculates a resistance value, and outputs a resistance control signal based on information on the calculated resistance value of the variable resistor,
The variable resistor comprises:
Wherein the air conditioner is variably set based on the resistance control signal. delete The method according to claim 1,
The relay unit includes:
And a diode element connected in parallel with the relay coil and the variable resistor. delete The method according to claim 1,
The relay control unit,
And outputs the resistance control signal for controlling the resistance value of the variable resistor to become larger as the relay driving voltage becomes larger. delete The method according to claim 1,
A second converter for converting the input AC power into DC power and outputting the DC power;
A voltage drop capacitor connected to an output terminal of the second converter;
And a voltage down unit connected to both ends of the voltage drop capacitor and outputting a level-changed DC voltage. 8. The method of claim 7,
The voltage-
And supplies the DC voltage to the relay control unit. 8. The method of claim 7,
The relay driver includes:
Wherein at least one of the switching elements is turned on and off based on the relay control signal to output the DC voltage of the voltage step-down unit to the relay unit. The method according to claim 1,
A dc-side capacitor connected to a dc terminal which is an output terminal of the first converter; And
And an inverter for converting the DC power of the dc stage into an AC power.

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