KR102296189B1 - Motor driving apparatus and home appliance including the same - Google Patents

Abstract

The present invention relates to a motor driving device and a home appliance having the same. A motor driving device and a home appliance having the same according to an embodiment of the present invention include a battery, a converter for boosting or stepping-down DC power from the battery, and converting dc power to AC power by a switching operation, , an inverter outputting the converted AC power to the motor, a battery voltage detector detecting an output voltage of the battery, and a controller controlling the converter to step-up or step-down based on the output voltage of the battery. Accordingly, when the battery-based motor is driven, the battery voltage can be boosted or decreased to be driven.

Description

Motor driving apparatus and home appliance including the same

The present invention relates to a motor driving device and a home appliance having the same, and more particularly, to a motor driving device capable of driving by increasing or decreasing a battery voltage when driving a battery-based motor, and to a home appliance having the same. .

A motor driving device is a device for driving a motor including a rotor that rotates and a stator around which a coil is wound.

The motor may be classified into a Samsung motor in which a three-phase winding is wound, a motor in which a single-phase winding is wound, and the like.

On the other hand, for the purpose of portability and the like when operating a motor driving device, a product using a battery is being developed.

According to the prior literature (Modeling and Comparison of Machine and Converter Losses for PWM and PAM in High-Speed Drives, IEEE 2014), a method of driving a motor by converting a DC power of a battery is disclosed.

According to this method, since the speed control of the motor is performed by controlling the input voltage of the inverter with the converter, the inverter performs only a predetermined switching operation.

On the other hand, according to the prior literature, the converter is a step-down (buck) converter, and since a boost operation is impossible, the battery output voltage is lowered, and when the battery output voltage is lowered, the maximum performance of the motor cannot be realized. have.

In addition, since the input voltage of the inverter is fixed, when the battery voltage drops, the input voltage of the inverter follows the battery voltage change as it is, so there is a problem in that performance such as motor speed is reduced.

SUMMARY OF THE INVENTION An object of the present invention is to provide a motor driving device capable of driving by boosting or decreasing a battery voltage when driving a battery-based motor, and a home appliance having the same.

Another object of the present invention is to provide a motor driving device capable of high-speed rotation even when a battery output voltage is lowered when a battery-driven motor is driven, and a home appliance having the same.

A motor driving device and a home appliance having the same according to an embodiment of the present invention for achieving the above object include a battery, a converter for boosting or stepping-down DC power from the battery and outputting it, and a dc terminal power supply by a switching operation Converts the AC power to AC power and includes an inverter for outputting the converted AC power to the motor, a battery voltage detector for detecting an output voltage of the battery, and a controller for controlling the converter to step-up or step-down based on the output voltage of the battery do.

Meanwhile, when the output voltage of the battery is equal to or less than the first reference value, the controller of the motor driving apparatus according to an embodiment of the present invention may control the converter to perform a boost operation.

On the other hand, when the output voltage of the battery is equal to or less than the first reference value and the rotation speed of the motor is equal to or greater than the first speed, the controller of the motor driving apparatus according to the embodiment of the present invention performs a step-up operation to generate a first level of direct current. It can be controlled to output voltage.

On the other hand, the controller of the motor driving apparatus according to the embodiment of the present invention, when the output voltage of the battery is less than or equal to the first reference value and the rotation speed of the motor is equal to or greater than the first speed, while the converter performs the step-up operation, the rotation speed of the motor It is possible to control the speed to be greater than or equal to the first speed without descending.

Meanwhile, the controller of the motor driving apparatus according to the embodiment of the present invention may control the operation of the converter and the inverter to stop when the output voltage of the battery is less than or equal to a second reference value lower than the first reference value.

Meanwhile, when the rotation speed of the motor is smaller than the first speed, the controller of the motor driving apparatus according to the embodiment of the present invention may control the voltage output from the converter to vary according to the rotation speed of the motor.

Meanwhile, when the rotation speed of the motor is smaller than the first speed, the controller of the motor driving apparatus according to the embodiment of the present invention may control the converter to perform a step-down operation according to the rotation speed of the motor.

On the other hand, the control unit of the motor driving apparatus according to the embodiment of the present invention, when the rotation speed of the motor is a second speed smaller than the first speed, the converter to output a DC voltage of a second level corresponding to the second speed control, and when the rotation speed of the motor is a third speed smaller than the second speed, the converter may control to output a DC voltage of a third level corresponding to the third speed and smaller than the second level.

Meanwhile, the motor driving apparatus according to an embodiment of the present invention may further include a dc terminal capacitor connected between the converter and the inverter.

On the other hand, in the converter of the motor driving apparatus according to the embodiment of the present invention, an inductor having one end connected between one end of a battery and one end of a dc stage capacitor, the other end of the inductor, and a converter switching in which one end is connected between the other end of the battery The device may include a diode device connected between the other end of the converter switching device and the other end of the dc terminal capacitor.

On the other hand, the inverter of the motor driving device according to an embodiment of the present invention includes three pairs of upper-arm switching elements and lower-arm switching elements, and the three phases of the motor are electrically connected to each node between the upper-arm switching element and the lower-arm switching element. can be

On the other hand, the converter of the motor driving device according to the embodiment of the present invention, between both ends of the dc terminal capacitor, the upper-arm switching element and the lower-arm switching element connected in series with each other, one end of the battery, the upper-arm switching element and the lower-arm switching element node It may include an inductor connected therebetween.

On the other hand, the motor driving device according to an embodiment of the present invention further includes a power module including three pairs of upper-arm switching elements and lower-arm switching elements, and one pair of upper-arm switching elements and lower-arm switching elements among the power modules is provided to the converter. is included, and two pairs of an upper-arm switching element and a lower-arm switching element among the power modules may be included in the inverter.

A motor driving device and a home appliance having the same according to another embodiment of the present invention for achieving the above object include a battery, a converter for converting and outputting DC power from the battery, and a dc terminal power supply by a switching operation Containing an inverter that converts AC power and outputs the converted AC power to the motor, and a dc terminal capacitor connected between the converter and the inverter, the converter is a phase-arm switching element connected in series with each other between both ends of the dc terminal capacitor and a lower arm switching device, and an inductor connected between one end of the battery and the nodes of the upper arm switching device and the lower arm switching device.

A motor driving device and a home appliance having the same according to an embodiment of the present invention include a battery, a converter for boosting or stepping-down DC power from the battery, and converting dc power to AC power by a switching operation, , an inverter outputting the converted AC power to the motor, a battery voltage detector detecting an output voltage of the battery, and a controller controlling the converter to step-up or step-down based on the output voltage of the battery. Accordingly, when the battery-based motor is driven, the battery voltage can be boosted or decreased to be driven. Accordingly, high-speed rotation driving is possible even when the battery output voltage is lowered when the battery-based motor is driven.

Meanwhile, when the output voltage of the battery is equal to or less than the first reference value, the controller of the motor driving apparatus according to an embodiment of the present invention may control the converter to perform a boost operation. Accordingly, high-speed rotation driving is possible even when the battery output voltage is lowered when the battery-based motor is driven.

On the other hand, when the output voltage of the battery is equal to or less than the first reference value and the rotation speed of the motor is equal to or greater than the first speed, the controller of the motor driving apparatus according to the embodiment of the present invention performs a step-up operation to generate a first level of direct current. It can be controlled to output voltage. Accordingly, high-speed rotation driving is possible even when the battery output voltage is lowered when the battery-based motor is driven.

On the other hand, the controller of the motor driving apparatus according to the embodiment of the present invention, when the output voltage of the battery is less than or equal to the first reference value and the rotation speed of the motor is equal to or greater than the first speed, while the converter performs the step-up operation, the rotation speed of the motor It is possible to control the speed to be greater than or equal to the first speed without descending. Accordingly, high-speed rotation driving is possible even when the battery output voltage is lowered when the battery-based motor is driven.

Meanwhile, the controller of the motor driving apparatus according to the embodiment of the present invention may control the operation of the converter and the inverter to stop when the output voltage of the battery is less than or equal to a second reference value lower than the first reference value. Accordingly, it is possible to protect the motor driving device.

Meanwhile, when the rotation speed of the motor is smaller than the first speed, the controller of the motor driving apparatus according to the embodiment of the present invention may control the voltage output from the converter to vary according to the rotation speed of the motor.

Meanwhile, when the rotation speed of the motor is smaller than the first speed, the controller of the motor driving apparatus according to the embodiment of the present invention may control the converter to perform a step-down operation according to the rotation speed of the motor. Accordingly, by stepping down the battery voltage when the battery-based motor is driven, the operating efficiency of the inverter is improved.

On the other hand, the control unit of the motor driving apparatus according to the embodiment of the present invention, when the rotation speed of the motor is a second speed smaller than the first speed, the converter to output a DC voltage of a second level corresponding to the second speed control, and when the rotation speed of the motor is a third speed smaller than the second speed, the converter may control to output a DC voltage of a third level corresponding to the third speed and smaller than the second level. Accordingly, when the battery-based motor is driven, the operating efficiency of the inverter is improved by stepping down the battery voltage according to the motor speed.

On the other hand, in the converter of the motor driving apparatus according to the embodiment of the present invention, an inductor having one end connected between one end of a battery and one end of a dc stage capacitor, the other end of the inductor, and a converter switching in which one end is connected between the other end of the battery The device may include a diode device connected between the other end of the converter switching device and the other end of the dc terminal capacitor. Accordingly, when the battery-based motor is driven, the battery voltage can be boosted or decreased to be driven.

On the other hand, the inverter of the motor driving device according to an embodiment of the present invention includes three pairs of upper-arm switching elements and lower-arm switching elements, and the three phases of the motor are electrically connected to each node between the upper-arm switching element and the lower-arm switching element. can be Accordingly, it is possible to drive the three-phase motor by boosting or stepping down the battery voltage when the motor is driven.

On the other hand, the converter of the motor driving device according to the embodiment of the present invention, between both ends of the dc terminal capacitor, the upper-arm switching element and the lower-arm switching element connected in series with each other, one end of the battery, the upper-arm switching element and the lower-arm switching element node It may include an inductor connected therebetween. Accordingly, when the battery-based motor is driven, the battery voltage can be boosted or decreased to be driven.

On the other hand, the motor driving device according to an embodiment of the present invention further includes a power module including three pairs of upper-arm switching elements and lower-arm switching elements, and one pair of upper-arm switching elements and lower-arm switching elements among the power modules is provided to the converter. is included, and two pairs of an upper-arm switching element and a lower-arm switching element among the power modules may be included in the inverter. Accordingly, it is possible to drive the single-phase motor by increasing or decreasing the battery voltage when the motor is driven.

A motor driving device and a home appliance having the same according to another embodiment of the present invention include a battery, a converter that converts and outputs DC power from the battery, and converts DC power to AC power by a switching operation, An inverter for outputting the converted AC power to the motor, and a dc stage capacitor connected between the converter and the inverter, wherein the converter includes an upper-arm switching element and a lower-arm switching element connected in series with each other between both ends of the dc stage capacitor, and an inductor connected between one end of the battery and the nodes of the upper-arm switching element and the lower-arm switching element. Accordingly, when the battery-based motor is driven, the battery voltage can be boosted or decreased to be driven. Accordingly, high-speed rotation driving is possible even when the battery output voltage is lowered when the battery-based motor is driven.

1A is a side elevation view of a vacuum cleaner which is an example of a home appliance according to an embodiment of the present invention.
1B is a perspective view of the cleaner from which the nozzle module is removed in FIG. 1A ;
1C is a side view of the cleaner of FIG. 1B.
2 is a perspective view of a dryer that is another example of a home appliance according to an embodiment of the present invention.
3 is an example of an internal block diagram of a home appliance according to an embodiment of the present invention.
FIG. 4 illustrates an example of an internal block diagram of the motor driving apparatus of FIG. 3 .
FIG. 5 is an example of an internal circuit diagram of the motor driving apparatus of FIG. 4 .
6A to 6B are diagrams referred to in the description of the operation of the motor driving apparatus of FIG. 4 .
7 is an internal block diagram of the inverter control unit of FIG. 5 .
8 is a diagram referred to in the description of the operation of the motor.
9A is an example of a circuit diagram of a motor driving apparatus according to the present invention.
9B to 9C are diagrams referred to in the description of the operation of FIG. 9A.
10A is an example of a circuit diagram of a motor driving apparatus according to an embodiment of the present invention.
10B to 10C are diagrams referred to in the description of the operation of FIG. 10A.
11 is an example of a circuit diagram of a motor driving apparatus according to another embodiment of the present invention.
12A to 12B are diagrams referenced in the operation description of FIG. 11 .
13 is a flowchart illustrating a method of operating a motor driving apparatus according to an exemplary embodiment of the present invention.

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

The suffixes "module" and "part" for the components used in the following description are given simply in consideration of the ease of writing the present specification, and do not give a particularly important meaning or role by themselves. Accordingly, the terms “module” and “unit” may be used interchangeably.

The home appliance described in this specification means a home appliance that has a motor and is driven according to the operation of the motor. For example, the home appliance may be exemplified in various ways, such as a cleaner, a hair dryer, a fan, a washing machine, an air purifier, an air conditioner, a water purifier, a refrigerator, a vehicle, and the like. Hereinafter, a vacuum cleaner and a hair dryer among home appliances will be mainly described.

1A is a side elevation view of a cleaner which is an example of a home appliance according to an embodiment of the present invention, FIG. 1B is a perspective view of the cleaner with the nozzle module removed in FIG. 1A, and FIG. 1C is a side view of the cleaner of FIG. 1B.

1A to 1C , a cleaner 100a, which is an example of a home appliance 100 according to an embodiment of the present invention, has a main body that forms a flow path P for guiding sucked air to be discharged to the outside. (10), a handle 30 coupled to the rear side of the main body 10, a nozzle module 70 detachably connected to the suction unit 11 of the main body 10, and a battery (Bt) for supplying power , a battery housing 40 in which the battery Bt is accommodated, and a fan module 50 disposed on the flow path P to move air in the flow path may be provided.

The nozzle module 70 may include a nozzle unit 71 provided to suck in external air, and an extension pipe 73 extending long from the nozzle unit 71 .

The extension pipe 73 connects the nozzle part 71 and the suction part 11 . The extension pipe 73 guides the air sucked in from the nozzle part 71 to be introduced into the suction passage P. One end of the extension pipe 73 may be detachably coupled to the suction unit 11 of the main body 10 . The user can clean the nozzle part 71 while holding the handle 30 while moving the nozzle part 71 while placing the nozzle part 71 on the floor.

The main body 10 includes a discharge cover 12 forming an exhaust port 10a, a dust collecting unit 13 for storing separated dust, and a fan module housing 14 accommodating the fan module 50 therein. may include.

The exhaust cover 12 may form an upper surface of the main body 10 . The exhaust cover 12 covers the upper portion of the fan module housing 14 .

The dust collector 13 may be formed in a cylindrical shape. The dust collector 13 may be disposed below the fan module housing 14 . Accordingly, a storage space for dust may be formed in the dust collecting unit 13 .

The fan module housing 14 may be formed to extend upwardly from the dust collector 13 . The fan module housing 14 is formed in a cylindrical shape. The extension part 31 of the handle 30 may be disposed on the rear side of the fan module housing 14 .

Within the fan module housing 14 , a fan module 50 may be disposed.

The fan module 50 includes a suction motor 230 that rotates the impeller 51 . The suction motor 230 may be located above the dust separation unit 20 .

The impeller 51 may be disposed below the suction motor 230 . The impeller 51 is coupled to the suction motor 230 and rotates by the rotational force of the suction motor 230 .

Meanwhile, the impeller 510 may pressurize the air by rotation so that the air in the flow path P is discharged through the exhaust port 10a.

Meanwhile, the cleaner 100a may include a motor driving unit 220 for controlling the suction motor 230 . The motor driving unit 220 may be disposed between the suction motor 230 and the dust collecting unit 13 . Meanwhile, the motor driving unit 220 may include a circuit element disposed on a PCB circuit board.

The handle 30 extends in the vertical direction and includes an additional extension 32 . The additional extension part 32 may be spaced apart from the main body 10 in the front-rear direction. A user may use the cleaner 100a while holding the additional extension 32 . The upper end of the additional extension part 32 is connected to the rear end of the extension part 31 . The lower end of the additional extension 32 is connected to the battery housing 40 .

The additional extension part 32 has a movement limiting part 32a for preventing the user's hand from moving in the longitudinal direction (up and down direction) of the additional extension part 32 while the user holds the additional extension part 32 . can be The movement limiting part 32a may protrude forward from the additional extension part 32 .

The movement limiting part 32a is disposed to be vertically spaced apart from the extension part 31 . In a state in which the user holds the additional extension part 32 , some fingers of the user's gripped hand are positioned above the movement limiting part 32a , and the remaining fingers are positioned below the movement limiting part 32a .

The handle 30 may include an inclined surface 33 facing the direction between the upper side and the rear side. The inclined surface 33 may be positioned on the rear surface of the extension part 31 . The input unit 3 may be disposed on the inclined surface 33 .

The battery Bt may supply power to the fan module 50 . The battery Bt may supply power to the noise control module. The battery Bt may be detachably disposed inside the battery housing 40 .

The battery housing 40 is coupled to the rear side of the main body 10 . The battery housing 40 is disposed below the handle 30 . The battery Bt is accommodated in the battery housing 40 . A heat dissipation hole for discharging heat generated from the battery Bt to the outside may be formed in the battery housing 40 .

Meanwhile, the exhaust port 10a may be disposed to face a specific direction (eg, an upward direction). The plurality of exhaust ports 10a may be divided into each other in the circumferential direction by the plurality of exhaust guides 12a. The plurality of exhaust ports 10a may be arranged to be spaced apart from each other by a predetermined distance along the circumferential direction.

2 is a perspective view of a dryer that is another example of a home appliance according to an embodiment of the present invention.

Referring to the drawings, the dryer 100b according to an embodiment of the present invention includes a main body CAS that forms a flow path for guiding sucked air to be discharged to the outside, and a cable connected to the rear side of the main body CAS. (CAB), which is detachably coupled to the front of the main body (CAS), may be provided with a front case (CASb) in which air in the flow path is discharged through the exhaust port (OTa).

On the other hand, the main body (CAS) of the dryer (100b), the suction port (INa) formed with an opening for sucking in the external air may be formed.

The dryer 100b is disposed inside the suction port INa, is disposed on the furnace P and rotates to move the air in the flow path, and a motor driving unit for driving the fan (FAN) (FIG. 3 of 220) may be provided.

On the other hand, the dryer (100b) is formed on the handle portion of the main body (CAS), the operation key (117a) operated to set the operation of the dryer (100b), the power key (117b) operated for power on / off setting ), and may be provided with a display 118 for displaying the operating state of the dryer (100b).

3 is an example of an internal block diagram of a home appliance according to an embodiment of the present invention.

Referring to the drawings, the home appliance 100 includes a motor 230 for rotating the fan FAN, a driving unit 220 for driving the motor 230 , and a power supply unit 270 for supplying power; , an operation key 117 , a display 118 , and a control unit 210 for controlling each unit in the home appliance 100 may be provided.

In particular, the control unit 210 may control the motor driving unit 220 .

The home appliance 100 may be controlled by the control operation of the controller 210 . In particular, the control unit 210 may control the motor driving unit 220 .

The motor driving unit 220 drives the motor 230 . Accordingly, the fan FAN is rotated by the motor 230 .

The control unit 210 operates by receiving an operation signal from the operation key 117 .

The operation key 117 may include an operation key 117a operated for setting the operation of the home appliance 100 and a power key 117b operated for setting the power on/off.

The control unit 210 may control the speed of the motor or the operating period of the motor in the home appliance 100 to vary according to the operation of the operation key 117a.

For example, the controller 210 may change the rotation speed of the motor 230 or control the heater (not shown) to operate according to the operation of the operation key 117a.

Also, the controller 210 may control the display 118 to display speed information of the motor, operation information of the motor, and the like.

Meanwhile, the control unit 210 controls the motor driving unit 220 , and the motor driving unit 220 controls the motor 230 to operate. At this time, a position sensing unit is not provided inside or outside the motor 230 to detect the position of the rotor of the motor. That is, the motor driving unit 220 may control the motor 230 by a sensorless method.

The motor driving unit 220 is for driving the motor 230 , and an inverter (not shown), an inverter control unit (not shown), and an output current detection unit (E of FIG. 5 ) for detecting an output current flowing through the motor 230 . ) can be provided. In addition, the motor driving unit 220 may be a concept that further includes a converter, etc. for supplying DC power input to an inverter (not shown).

For example, the inverter control unit ( 430 in FIG. 5 ) in the motor driving unit 220 estimates the rotor position of the motor 230 based on the output current io. Then, based on the estimated rotor position, the motor 230 is controlled to rotate.

Specifically, the inverter controller ( 430 in FIG. 5 ) generates a pulse width modulation (PWM) switching control signal (Sic in FIG. 5 ) based on the output current io and outputs it to an inverter (not shown). Then, the inverter (not shown) performs a high-speed switching operation to supply AC power of a predetermined frequency to the motor 230 . Then, the motor 230 is rotated by AC power having a predetermined frequency.

Meanwhile, the power supply unit 270 may receive commercial AC power to the outside, convert it into DC power, and supply it.

Meanwhile, the power supply unit 270 may include a battery BAT to store the converted DC power.

The motor driving unit 220 will be described later with reference to FIG. 4 .

FIG. 4 illustrates an example of an internal block diagram of the motor driving apparatus of FIG. 3 , and FIG. 5 is an example of an internal circuit diagram of the motor driving apparatus of FIG. 4 .

Referring to the drawings, the motor driving device 220 according to the embodiment of the present invention is for driving the motor in a sensorless manner, and may include an inverter 420 and an inverter controller 430 . have.

In addition, the motor driving device 220 according to an embodiment of the present invention includes a battery (BAT), a battery voltage detection unit (A), a converter 410, a dc stage voltage detection unit (B), a dc stage capacitor (C), an output It may include a current detection unit (E).

Meanwhile, the motor driving apparatus 220 according to the embodiment of the present invention may further include an input current detection unit T, an input voltage detection unit Z, a switching unit 233 , and the like.

Meanwhile, the switching unit 233 may _{be connected between the commercial AC power source 405 , v s} and the battery BAT, and may switch to supply the commercial AC power source Vs to the battery BAT.

In this case, the switching unit 233 may include an ac/dc converter (not shown) that converts commercial AC power into DC power.

Meanwhile, the input current detector T may detect the input current ib flowing into the battery BAT. To this end, as the input current detector T, a current transformer (CT), a shunt resistor, or the like may be used. The detected input current ib may be input to the inverter controller 430 as a discrete signal in the form of a pulse.

Meanwhile, the input voltage detector Z may detect the input voltage Vb input to the battery BAT. To this end, the input voltage detection unit Z may include a resistance element, an amplifier, and the like. The detected input voltage Vb may be input to the inverter controller 430 as a discrete signal in the form of a pulse.

The battery voltage detector A may detect the battery voltage Vbat output from the battery BAT. To this end, the battery voltage detection unit A may include a resistance element, an amplifier, and the like. The detected battery voltage Vbat may be input to the inverter controller 430 as a discrete signal in the form of a pulse.

The converter 410 converts the level of the DC power output from the battery BAT or bypasses it as it is, and outputs the DC power.

Meanwhile, the converter 410 according to the embodiment of the present invention may increase or decrease the voltage according to the output voltage of the battery BAT or the target speed of the motor 230 .

To this end, the converter 410 may include a switching element, an inductor, and the like.

The dc terminal capacitor C may store input DC power. In the drawings, one element is exemplified as a dc terminal capacitor (C), but a plurality of elements may be provided to ensure element stability.

On the other hand, since DC power is stored at both ends (a-b ends) of the dc terminal capacitor C, it may be referred to as a dc terminal or a dc link terminal.

The dc terminal voltage detection unit B may detect the dc terminal voltage Vdc that is both ends of the dc terminal capacitor C. To this end, the dc terminal voltage detection unit B may include a resistance element, an amplifier, and the like. The detected dc terminal voltage Vdc may be input to the inverter controller 430 as a discrete signal in the form of a pulse.

Meanwhile, the inverter 420 may be connected to the dc terminals (a-b terminals), convert DC power to AC power by a switching operation, and output the converted AC power to the motor 230 .

The inverter 420 includes a plurality of inverter switching elements, and converts a DC power supply (Vdc) smoothed by an on/off operation of the switching elements into a three-phase AC power supply (va, vb, vc) of a predetermined frequency, three-phase output to the synchronous motor 230 .

Inverter 420 is a pair of upper-arm switching elements (Sa, Sb, Sc) and lower-arm switching elements (S'a, S'b, S'c) connected in series with each other, and a total of three pairs of upper and lower arms The switching elements are connected in parallel with each other (Sa&S'a, Sb&S'b, Sc&S'c). A diode is connected in anti-parallel to each of the switching elements Sa, S'a, Sb, S'b, Sc, and S'c.

The switching elements in the inverter 420 turn on/off the respective switching elements based on the inverter switching control signal Sic from the inverter controller 430 . Accordingly, the three-phase AC power having a predetermined frequency is output to the three-phase synchronous motor 230 .

The inverter controller 430 may control the switching operation of the inverter 420 based on the sensorless method. To this end, the inverter control unit 430 may receive _{an output current i o detected by the output current detection unit E .}

The inverter control unit 430 outputs the inverter switching control signal Sic to the inverter 420 in order to control the switching operation of the inverter 420 . The inverter switching control signal Sic is a pulse width modulation (PWM) switching control signal, and is generated and output based _{on the output current i o detected by the output current detection unit E .} A detailed operation of the output of the inverter switching control signal Sic in the inverter controller 430 will be described later with reference to FIG. 7 .

The output current detection unit E may detect a phase current flowing between the three-phase motors 230 , that is, the output current io.

The output current detection unit E may be disposed in the inverter 420 and the motor 230 to detect a current flowing through the motor 230 as shown in the drawing.

As shown in the figure, the output current detection unit E may include three resistance elements. Through the three resistor elements, it is possible to detect a phase current (ia, ib, ic) that is an output current (io) flowing through the motor 230 . The detected output current (ia, ib, ic) may be applied to the inverter controller 430 as a discrete signal in the form of a pulse, and based on the detected output current (ia, ib, ic), the inverter A switching control signal Sic is generated.

Meanwhile, in this specification, ia, ib, ic, or io are used interchangeably as the output current.

Meanwhile, unlike the drawing, the output current detection unit E may include two resistance elements. The phase current of the other phase can be calculated using the three-phase balance.

On the other hand, unlike the figure, the output current detection unit (E) is disposed between the dc terminal capacitor (C) and the inverter (420), and includes one shunt resistor (Rs), the current flowing through the motor (230) can also be detected. This method may be referred to as a one-shunt method.

According to the 1 shunt method, the output current detection unit (E) uses one shunt resistor element (Rs) to turn on the lower arm switching element of the inverter 420, time-divisionally, the output current flowing through the motor 230 ( idc), a phase current may be detected.

The detected output current i _o may be applied to the inverter control unit 430 as a discrete signal in the form of a pulse _{, and based on the detected output current i o} , the inverter switching control signal Sic is created Hereinafter, the detected output current (i _o ) may be described in parallel as the three-phase output current (ia, ib, ic).

Meanwhile, the three-phase motor 230 includes a stator and a rotor, and each phase AC power of a predetermined frequency is applied to the coils of the stators of each phase (a, b, c phase), and the rotor rotates. will do

The motor 230 includes, for example, a Surface-Mounted Permanent-Magnet Synchronous Motor (SMPMSM), an Interior Permanent Magnet Synchronous Motor (IPMSM), and a synchronous relay. It may include a Synchronous Reluctance Motor (Synrm) and the like. Among them, SMPMSM and IPMSM are Permanent Magnet Synchronous Motor (PMSM) applied with permanent magnet, and Synrm is characterized by no permanent magnet.

6A to 6B are diagrams referred to in the description of the operation of the motor driving apparatus of FIG. 4 .

6A illustrates a case in which the switching unit 233 and the inverter 420 operate.

Accordingly, the inverter control unit 430, the input power from the commercial AC power supply Vs, is supplied to the battery BAT through the switching unit 233 like the current path of Ipath1, and is supplied to the battery BAT. The stored battery power may be controlled to be supplied to the motor 230 through the converter 410 and the inverter 420 like the current path of Ipath2 .

6B illustrates a case in which the switching unit 233 is turned off and the inverter 420 operates.

Accordingly, the inverter control unit 430, the input power from the commercial AC power supply (Vs) is not supplied to the battery (BAT), and the battery power from the battery (BAT) is converted to the converter ( 410), through the inverter 420, can be controlled to be supplied to the motor 230.

7 is an internal block diagram of the inverter control unit of FIG. 5 .

Referring to FIG. 7 , the inverter control unit 430 includes an axis converting unit 310 , a speed calculating unit 320 , a current command generating unit 330 , a voltage command generating unit 340 , an axis converting unit 350 , and A switching control signal output unit 360 may be included.

The axis conversion unit 310 may convert the three-phase output current (ia, ib, ic) or the estimated current detected by the output current detection unit (E) into a two-phase current (iα, iβ) of a stationary coordinate system. have.

Meanwhile, the axis conversion unit 310 may convert the two-phase currents (iα, iβ) of the stationary coordinate system into the two-phase currents (id, iq) of the rotational coordinate system.

)와 연산된 속도(

)를 출력할 수 있다.The speed calculating unit 320, the calculated position (

) and the calculated speed (

) can be printed.

)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, the calculation speed (

) and the speed command value (ω ^* _r ), a current command value (i ^* _q ) is generated. For example, the current command generation unit 330 may set the calculation speed (

) and the speed command value (ω ^* _r ) based on the difference, the PI controller 335 may perform PI control and generate a ^{current command value (i *} _{q ).} In the drawing, the q-axis current command value (i ^* _q ) is exemplified as the current command value, but unlike the drawing, it is also possible to generate the ^{d-axis current command value (i *} _{d ) together.} On the other hand, the value of the d-axis current command value (i ^* _d ) may be set to 0.

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

Next, the voltage command generation unit 340 includes the d-axis and q-axis currents (i _d ,i _q ) that are axis-transformed into the two-phase rotational coordinate system by the axis transformation unit, and the current command values ( Based on i ^* _d ,i ^* _q ), d-axis and q-axis voltage command values (v ^* _d ,v ^* _q ) are generated. 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 ), q} A shaft voltage setpoint (v ^* _q ) can be generated. In addition, 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 ), and the d-axis voltage} A setpoint (v ^* _d ) can be generated. On the other hand, the voltage command generation unit 340, d-axis, q-axis voltage command value (v ^* _d , v ^* _q ) may further include a limiter (not shown) for limiting the level so as not to exceed the allowable range. .

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

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

) and d-axis and q-axis voltage command values (v ^* _d ,v ^* _q ) are received and axis transformation is performed.

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

) can be used.

Then, the axis transformation unit 350 performs transformation from the two-phase stationary coordinate system to the single-phase stationary coordinate system. Through this conversion, the axis conversion unit 1050 outputs a single-phase output voltage command value (v ^* a).

The switching control signal output unit 360 generates and outputs the switching control signal Sic for the inverter according to the pulse width modulation (PWM) method based on the single-phase output voltage command value (v ^{* a).}

The output inverter switching control signal Sic may be converted into a gate driving signal by a gate driver (not shown) and input to a gate of each switching element in the inverter 420 . Accordingly, each of the switching elements Sa, S'a, Sb, and S'b in the inverter 420 performs a switching operation.

8 is a diagram referenced in the description of the operation of the motor.

Referring to the drawing, the motor 230 may be divided into an alignment section Pon, an open loop section Pop, and a closed loop section Pcl to operate.

The inverter controller 430 may control the rotor of the motor 230 to be aligned at a predetermined position by flowing a predetermined current to the motor 230 during the alignment period Pon. Here, the constant current may be a magnetic flux current.

Accordingly, during the alignment section Pon, the rotation speed of the motor 230 becomes 0 as shown in the figure.

Next, the inverter control unit 430 may control the open loop period Pop to be performed while the rotation speed of the motor 230 is continuously increased after the alignment period Pon.

During the open loop section Pop, as in FIG. 7 , the speed command value ω ^* _r continuously rises, but without feedback on the output current io detected by the output current detection unit E, the speed command value Based only on (ω ^* _r ), the motor 230 is driven.

Next, the inverter control unit 430 may control the closed loop period Pcl to be performed while the rotation speed of the motor 230 continuously increases after the open loop period Pop.

During the closed loop period Pcl, as in FIG. 7, the speed command value ω ^* _r is continuously increased or variable, and the inverter control unit 430 controls the output current io detected by the output current detection unit E. ), the motor 230 may be driven based on the difference between the detected output current io and the speed command value ω ^* _{r .}

9A is an example of a circuit diagram of a motor driving apparatus related to the present invention, and FIGS. 9B to 9C are diagrams referenced in the operation description of FIG. 9A.

First, referring to FIG. 9A , the motor driving apparatus 900 according to the present invention includes a battery BAT, a converter 410a that converts and outputs DC power from the battery BAT, and a direct current from the converter 410a. An inverter 420 that converts power into AC power and outputs it to the motor 230 may be provided.

According to the drawing, the converter 410a includes switching elements SWa1 and SWa2 connected in series with each other, a node between the switching elements SWa1 and SWa2, and an inductor La connected to one end of the dc terminal. can

9B illustrates a speed waveform MVa of the motor 230 , an input voltage waveform Viva to the inverter 230 , and an output voltage waveform Vbta of the battery BAT.

As in the Pa1 and Pa2 sections, when the motor speed is as low as Lva and Lvb, the converter 410a may perform a voltage step-down operation to output voltages equal to Vm2 and Vm3, respectively.

9C is a diagram exemplifying the operation of the converter 410a in the Pa1 and Pa2 sections.

Referring to the drawing, at a first time point, due to the turn-on of the first switching element SWa1 and the turn-off of the second switching element SWa2, the power of the battery BAT is reduced like a current path such as ipatha1. , may be stored in the dc terminal capacitor C through the first switching element SWa1 and the inductor La.

Next, at a second time point, by turning off the first switching element SWa1 and turning on the second switching element SWa2 , the energy stored in the inductor La, such as a current path such as ipatha2, is dc However, it may be output to the capacitor C. Accordingly, voltage drop is performed.

Meanwhile, as in the Pa3 section, when the motor speed increases to Lvc, the converter 410a bypasses the output voltage of the battery BAT almost as it is and outputs it.

At this time, as shown in FIG. 9b , when the output voltage of the battery BAT is lowered to less than or equal to the first reference value ref1 after the PPa time point, the converter 410a cannot step-up operation, so inevitably, the inverter ( The voltage input to the 420 is also lowered to less than or equal to the first reference value ref1 according to the output voltage of the battery BAT.

Accordingly, after the PPa time point, as the output voltage of the battery BAT is lowered, the speed of the motor cannot maintain Lvc and has no choice but to rotate at a speed lower than Lvc. Accordingly, there is a disadvantage that the maximum performance of the motor cannot be realized.

In order to solve this problem, the present invention proposes a converter capable of performing step-down as well as step-up in the converter 410 . This will be described with reference to FIG. 10A and below.

10A is an example of a circuit diagram of a motor driving apparatus according to an embodiment of the present invention, and FIGS. 10B to 10C are diagrams referenced in the operation description of FIG. 10A.

Referring to the drawings, the motor driving apparatus 1000 according to the embodiment of the present invention includes a battery BAT, a converter 410b for boosting or stepping-down DC power from the battery BAT and outputting it, and a switching operation. By this, the inverter 420 for converting the dc terminal power to AC power and outputting the converted AC power to the motor 230, the battery voltage detection unit A for detecting the output voltage of the battery BAT, and the battery ( BAT), based on the output voltage of the converter 410b includes an inverter control unit 430 that controls the step-up or step-down.

Accordingly, when the battery (BAT)-based motor 230 is driven, the battery (BAT) voltage can be boosted or lowered to be driven. Accordingly, when the battery (BAT)-based motor 230 is driven, high-speed rotation driving is possible even when the output voltage of the battery (BAT) is lowered.

On the other hand, the converter 410b according to the embodiment of the present invention includes an inductor Lb having one end connected between one end of the battery BAT and one end a of the dc terminal capacitor C, and the inductor Lb. A converter switching element Swb having one end connected between the other end and the other end of the battery BAT, and a diode element connected between the other end of the converter switching element Swb and the other end b of the dc stage capacitor C ( Db) may be included. Accordingly, when the battery (BAT)-based motor 230 is driven, the battery (BAT) voltage can be boosted or lowered to be driven.

On the other hand, the inverter 420 of the motor driving device 220 according to the embodiment of the present invention includes three pairs of upper-arm switching elements and lower-arm switching elements (Sa to Sc, S'a to S'c), and upper-arm switching Three phases of the motor 230 may be electrically connected to each node na, nb, and nc between the element and the lower arm switching element. Accordingly, when the motor 230 of the three-phase motor 230 is driven, the voltage of the battery BAT may be boosted or decreased to drive the motor 230 .

On the other hand, the inverter 420 of the motor driving device 220 according to the embodiment of the present invention is a power module ( IPM) can be used as it is.

Meanwhile, when the output voltage of the battery BAT is equal to or less than the first reference value Ref1 , the inverter controller 430 according to an embodiment of the present invention may control the converter 410b to perform a boost operation. Accordingly, when the battery (BAT)-based motor 230 is driven, high-speed rotation driving is possible even when the output voltage of the battery (BAT) is lowered.

On the other hand, in the inverter control unit 430 according to the embodiment of the present invention, when the output voltage of the battery BAT is less than or equal to the first reference value Ref1 and the rotation speed of the motor 230 is greater than or equal to the first speed Lvc, The converter 410b may be controlled to output a DC voltage of the first level Vm1 by performing a step-up operation. Accordingly, when the battery (BAT)-based motor 230 is driven, high-speed rotation driving is possible even when the output voltage of the battery (BAT) is lowered.

On the other hand, in the inverter control unit 430 according to the embodiment of the present invention, when the output voltage of the battery BAT is less than or equal to the first reference value Ref1 and the rotation speed of the motor 230 is greater than or equal to the first speed Lvc, While the converter 410b performs the step-up operation, the rotation speed of the motor 230 may be controlled to be equal to or greater than the first speed Lvc without decreasing. Accordingly, when the battery (BAT)-based motor 230 is driven, high-speed rotation driving is possible even when the output voltage of the battery (BAT) is lowered.

On the other hand, when the output voltage of the battery BAT is less than or equal to a second reference value ref2 that is lower than the first reference value Ref1, the inverter control unit 430 according to the embodiment of the present invention includes the converter 410b and the inverter 420 . You can control the operation to stop. Accordingly, it is possible to protect the motor driving device 220 .

On the other hand, when the rotation speed of the motor 230 is smaller than the first speed Lvc, the inverter control unit 430 according to the embodiment of the present invention outputs the output from the converter 410b according to the rotation speed of the motor 230 . The voltage can be controlled to be variable.

On the other hand, in the inverter control unit 430 according to the embodiment of the present invention, when the rotation speed of the motor 230 is smaller than the first speed Lvc, the converter 410b is step-down according to the rotation speed of the motor 230 . You can control the action to be performed. Accordingly, when the battery (BAT)-based motor 230 is driven, the voltage of the battery (BAT) is stepped down, so that the operating efficiency of the inverter 420 is improved.

On the other hand, the inverter control unit 430 according to the embodiment of the present invention, when the rotation speed of the motor 230 is the second speed Lva smaller than the first speed Lvc, in the converter 410b, the second speed Control to output a DC voltage of the second level Vm2 corresponding to Lva, and when the rotation speed of the motor 230 is a third speed Lvb smaller than the second speed Lva, the converter 410b , it may be controlled to output a DC voltage of a third level Vm3 that corresponds to the third speed Lvb and is smaller than the second level Vm2. Accordingly, when the battery BAT-based motor 230 is driven, the voltage of the battery BAT is stepped down according to the speed of the motor 230 , thereby improving the operating efficiency of the inverter 420 .

10B illustrates a speed waveform MVb of the motor 230 , an input voltage waveform Vivb to the inverter 230 , and an output voltage waveform Vbta of the battery BAT.

As in the Pb1 and Pb2 sections, when the motor speed is as low as Lva and Lvb, the converter 410b may perform a voltage step-down operation to output voltages equal to Vm2 and Vm3, respectively.

On the other hand, as in the Pb3 section, when the speed of the motor increases to Lvc, the converter 410b bypasses the output voltage of the battery BAT almost as it is and outputs it.

At this time, as shown in FIG. 10B , when the output voltage of the battery BAT is lowered to less than or equal to the first reference value ref1 after the time PPb, the converter 410b performs a step-up operation. The step-up operation will be described with reference to the drawing in Fig. 10C.

10C is a diagram illustrating the operation of the converter 410b in the Pb4 section.

Referring to the drawing, at a first time point, due to the turn-on of the converter switching element SWb, power of the battery BAT passes through the switching element SWb, such as a current path such as ipathb1, to the inductor Lb. can be stored in

Next, at a second time point, by turning off the switching element SWb, energy stored in the inductor Lb may be output to the dc terminal capacitor C, like a current path such as ipathb2 . Accordingly, voltage boosting is performed.

On the other hand, after the PPb time point, by the step-up operation of the converter 410b, the input voltage of the inverter 420 maintains approximately Vm1, etc. as it is, as shown in FIG. 10b. Therefore, the input voltage of the inverter 420 is It becomes higher than the output voltage of the battery BAT.

Accordingly, after the PPb time point, as in the Ara section, the speed of the motor 230 is based on the input voltage of the inverter 420 maintaining Vm1, Lvc can be maintained almost as it is. Accordingly, it is possible to realize the maximum performance of the motor despite a decrease in the output voltage of the battery BAT.

11 is an example of a circuit diagram of a motor driving apparatus according to another embodiment of the present invention, and FIGS. 12A to 12B are diagrams referenced in the operation description of FIG. 11 .

Referring to the drawings, a motor driving apparatus 1100 according to an embodiment of the present invention includes a battery BAT, a converter 410 for boosting or stepping-down DC power from the battery BAT and outputting it, and a switching operation. By this, the inverter 420 for converting the dc terminal power to AC power and outputting the converted AC power to the motor 230, the battery voltage detection unit A for detecting the output voltage of the battery BAT, and the battery ( BAT), based on the output voltage of the converter 410 includes an inverter control unit 430 for controlling the step-up or step-down.

Accordingly, when the battery (BAT)-based motor 230 is driven, the battery (BAT) voltage can be boosted or lowered to be driven. Accordingly, when the battery (BAT)-based motor 230 is driven, high-speed rotation driving is possible even when the output voltage of the battery (BAT) is lowered.

On the other hand, the converter 410 according to the embodiment of the present invention, between both ends of the dc terminal capacitor (C), the upper-arm switching element (Sa) and the lower-arm switching element (S'a) and the battery (BAT) connected in series with each other. ) and an inductor L connected between the upper-arm switching element Sa and the node na of the lower-arm switching element S'a. Accordingly, when the battery (BAT)-based motor 230 is driven, the battery (BAT) voltage can be boosted or lowered to be driven.

At this time, as the lower-arm switching element S'a is turned on, the energy of the battery BAT is stored in the inductor L, the lower-arm switching element S'a is turned off, and the upper-arm switching element Sa is turned on. Accordingly, the energy of the inductor L may be transferred to the dc terminal capacitor C.

Meanwhile, the motor driving device 220 according to the embodiment of the present invention may include a power module (IPM) including three pairs of upper-arm switching elements and lower-arm switching elements (Sa to Sc, S'a to S'c). can

At this time, one pair of upper-arm switching element Sa and lower-arm switching element S'a of the power module IPM is included in the converter 410, and two pairs of upper-arm switching element and lower arm of the power module IPM are included. The switching elements Sb, Sc, S'b, and S'c may be included in the inverter 420 . In this case, the motor 230 may be a single-phase motor.

Accordingly, circuits of the converter 410 and the inverter 420 can be simply implemented using one power module, without a separate additional power module.

Meanwhile, when the output voltage of the battery BAT is equal to or less than the first reference value Ref1 , the inverter controller 430 according to an embodiment of the present invention may control the converter 410 to perform a boost operation. Accordingly, when the battery (BAT)-based motor 230 is driven, high-speed rotation driving is possible even when the output voltage of the battery (BAT) is lowered.

On the other hand, in the inverter control unit 430 according to the embodiment of the present invention, when the output voltage of the battery BAT is less than or equal to the first reference value Ref1 and the rotation speed of the motor 230 is greater than or equal to the first speed Lvc, The converter 410 may be controlled to output the DC voltage of the first level Vm1 by performing a step-up operation. Accordingly, when the battery (BAT)-based motor 230 is driven, high-speed rotation driving is possible even when the output voltage of the battery (BAT) is lowered.

On the other hand, in the inverter control unit 430 according to the embodiment of the present invention, when the output voltage of the battery BAT is less than or equal to the first reference value Ref1 and the rotation speed of the motor 230 is greater than or equal to the first speed Lvc, While the converter 410 performs the step-up operation, the rotation speed of the motor 230 may be controlled to be equal to or greater than the first speed Lvc without decreasing. Accordingly, when the battery (BAT)-based motor 230 is driven, high-speed rotation driving is possible even when the output voltage of the battery (BAT) is lowered.

On the other hand, the inverter controller 430 according to the embodiment of the present invention, when the output voltage of the battery BAT is less than or equal to a second reference value ref2 lower than the first reference value Ref1, the converter 410 and the inverter 420 You can control the operation to stop. Accordingly, it is possible to protect the motor driving device 220 .

On the other hand, the inverter control unit 430 according to the embodiment of the present invention, when the rotation speed of the motor 230 is less than the first speed (Lvc), according to the rotation speed of the motor 230, the output from the converter 410 The voltage can be controlled to be variable.

On the other hand, in the inverter control unit 430 according to the embodiment of the present invention, when the rotation speed of the motor 230 is less than the first speed Lvc, the converter 410 is step-down according to the rotation speed of the motor 230 . You can control the action to be performed. Accordingly, when the battery (BAT)-based motor 230 is driven, the voltage of the battery (BAT) is stepped down, so that the operating efficiency of the inverter 420 is improved.

On the other hand, the inverter control unit 430 according to the embodiment of the present invention, when the rotation speed of the motor 230 is a second speed Lva smaller than the first speed Lvc, in the converter 410, the second speed Control to output the DC voltage of the second level (Vm2) corresponding to (Lva), and when the rotation speed of the motor 230 is a third speed (Lvb) that is smaller than the second speed (Lva), the converter (410) , it may be controlled to output a DC voltage of a third level Vm3 that corresponds to the third speed Lvb and is smaller than the second level Vm2. Accordingly, when the battery BAT-based motor 230 is driven, the voltage of the battery BAT is stepped down according to the speed of the motor 230 , thereby improving the operating efficiency of the inverter 420 .

12A illustrates a speed waveform MVb of the motor 230 , an input voltage waveform Vivc to the inverter 230 , and an output voltage waveform Vbta of the battery BAT.

As in the Pc1 and Pc2 sections, when the motor speed is low as Lva and Lvb, the converter 410 may bypass the battery voltage as it is without voltage drop.

Meanwhile, as in the Pc3 section, when the speed of the motor increases to Lvc, the converter 410 bypasses the output voltage of the battery BAT almost as it is and outputs it.

At this time, as shown in FIG. 12A , when the output voltage of the battery BAT decreases to less than or equal to the first reference value ref1 after the time PPc, the converter 410 performs a step-up operation. The step-up operation will be described with reference to the drawing in Fig. 12B.

12B is a diagram illustrating the operation of the converter 410 in the Pc4 section.

Referring to the drawing, at a first time point, by the turn-on of the lower-arm switching element S'a and the turn-off of the upper-arm switching element Sa, the power of the battery BAT is reduced, such as a current path such as ipathc1. , may be stored in the inductor (L).

Next, at the second time point, by the turn-off of the lower-arm switching element S'a, and the turn-on of the upper-arm switching element Sa, the energy stored in the inductor L, such as a current path such as ipathc2, is dc However, it may be output to the capacitor C. Accordingly, voltage boosting is performed.

On the other hand, after the time PPc, by the step-up operation of the converter 410, the input voltage of the inverter 420 maintains approximately Vm1, etc. as it is, as shown in FIG. 12A. It becomes higher than the output voltage of the battery BAT.

Accordingly, after the PPc time point, as in the Arb section, the speed of the motor 230 can maintain Lvc almost as it is based on the input voltage of the inverter 420 maintaining Vm1. Accordingly, it is possible to realize the maximum performance of the motor despite a decrease in the output voltage of the battery BAT.

13 is a flowchart illustrating a method of operating a motor driving apparatus according to an exemplary embodiment of the present invention.

Referring to the drawings, the motor driving apparatus 220 according to the embodiment of the present invention may supply power to the converter 410 and the inverter 420 according to a power-on input (S1310).

Next, the inverter control unit 430 of the motor driving apparatus 220 according to the embodiment of the present invention may control the motor 230 to rotate according to a setting mode.

For example, as shown in FIG. 10B or 12A , the motor 230 may be controlled to rotate at a first speed Lvc, a second speed LVa, or a third speed LVb.

Meanwhile, the inverter control unit 430 may calculate the speed of the motor 230 based on the output current io of the output current detection unit E . In addition, a switching control signal Sic based on a variable pulse width may be output to the inverter 420 so that the motor 230 rotates according to the target speed.

Next, the inverter control unit 430 of the motor driving apparatus 220 according to the embodiment of the present invention determines whether the battery voltage Vbat is equal to or less than a first reference value ref1 (S1325).

The inverter controller 430 may determine whether the battery voltage Vbat detected by the battery voltage detector A is equal to or less than the first reference value ref1.

Meanwhile, when the battery voltage Vbat is equal to or less than the first reference value ref1, the inverter controller 430 may control the converter to perform a step-up operation (S1330).

As described with reference to FIGS. 10A to 12B , the inverter controller 430 may output a control signal to a switching element inside the converters 410b and 410 so that the converter performs a step-up operation.

Accordingly, as in the Ara section of FIG. 10B and the Arb section of FIG. 12A , the motor 230 can rotate at high speed despite the drop in the battery voltage. Accordingly, in spite of the drop in the battery voltage, it is possible to maintain the motor performance.

Next, the inverter control unit 430 of the motor driving device 220 according to the embodiment of the present invention determines whether the battery voltage Vbat is less than or equal to a second reference value ref2 lower than the first reference value ref1 ( S1340).

The inverter controller 430 may determine whether the battery voltage Vbat detected by the battery voltage detector A is equal to or less than the second reference value ref2. In this case, the second reference value ref2 may correspond to a minimum allowable value for driving the motor.

Meanwhile, when the battery voltage Vbat is equal to or less than the second reference value ref2 , the inverter controller 430 may control the operation of the motor driving device 220 to be turned off in order to protect the motor driving device 220 . (S1350). Accordingly, the operation of the converters 410b and 410 and the inverter 420 in the motor driving device 220 is turned off.

A motor driving device and a home appliance having the same according to an embodiment of the present invention, the configuration and method of the embodiments described above are not limitedly applicable, but the embodiments are each so that various modifications can be made. All or part of the embodiments may be selectively combined and configured.

On the other hand, the motor driving method or the home appliance operating method of the present invention can be implemented as a processor-readable code on a processor-readable recording medium provided in the motor driving device or the home appliance. The processor-readable recording medium includes all types of recording devices in which data readable by the processor is stored.

In addition, although preferred embodiments of the present invention have been illustrated and described above, the present invention is not limited to the specific embodiments described above, and the technical field to which the present invention belongs without departing from the gist of the present invention as claimed in the claims Various modifications are possible by those of ordinary skill in the art, and these modifications should not be individually understood from the technical spirit or prospect of the present invention.

Claims (18)

battery;
a converter for boosting or stepping-down the DC power from the battery and outputting it;
an inverter that converts the dc stage power into AC power by a switching operation and outputs the converted AC power to the motor;
a battery voltage detector detecting an output voltage of the battery;
and an inverter controller controlling the converter to step-up or step-down based on the output voltage of the battery. According to claim 1,
The inverter control unit,
When the output voltage of the battery is equal to or less than a first reference value, the motor driving apparatus according to claim 1, wherein the converter is controlled to perform a step-up operation. According to claim 1,
The inverter control unit,
When the output voltage of the battery is less than or equal to a first reference value and the rotation speed of the motor is greater than or equal to the first speed, the converter performs a step-up operation to output a first level of DC voltage. . According to claim 1,
The inverter control unit,
When the output voltage of the battery is less than or equal to the first reference value and the rotation speed of the motor is greater than or equal to the first speed, the converter performs the boosting operation so that the rotation speed of the motor is greater than or equal to the first speed without decreasing. Motor drive device, characterized in that the control. 4. The method of claim 3,
The inverter control unit,
When the output voltage of the battery is less than or equal to a second reference value lower than the first reference value, the motor driving apparatus according to claim 1, wherein the control to stop the operation of the converter and the inverter. 4. The method of claim 3,
The inverter control unit,
When the rotation speed of the motor is smaller than the first speed, the motor driving apparatus according to claim 1, wherein the voltage output from the converter is controlled to vary according to the rotation speed of the motor. 4. The method of claim 3,
The inverter control unit,
When the rotation speed of the motor is less than the first speed, the converter according to the rotation speed of the motor, characterized in that the control to perform a step-down operation. 7. The method of claim 6,
the inverter control unit
When the rotation speed of the motor is a second speed that is smaller than the first speed, the converter controls to output a DC voltage of a second level corresponding to the second speed,
When the rotation speed of the motor is a third speed smaller than the second speed, the converter controls to output a DC voltage of a third level corresponding to the third speed and smaller than the second level motor drive device. According to claim 1,
Further comprising; a dc terminal capacitor connected between the converter and the inverter,
The converter is
an inductor having one end connected between one end of the battery and one end of the dc terminal capacitor;
a converter switching element having one end connected between the other end of the inductor and the other end of the battery;
and a diode element connected between the other end of the converter switching element and the other end of the dc terminal capacitor. 10. The method of claim 9,
When the converter switching element is turned on, energy of the battery is stored in the inductor, and when the converter switching element is turned off, the energy of the inductor is transferred to the dc terminal capacitor. 10. The method of claim 9,
The inverter is
It includes three pairs of upper-arm switching elements and lower-arm switching elements,
The motor driving apparatus according to claim 1, wherein the three phases of the motor are electrically connected to each node between the upper arm switching element and the lower arm switching element. According to claim 1,
Further comprising; a dc terminal capacitor connected between the converter and the inverter,
The converter is
an upper-arm switching element and a lower-arm switching element connected in series with each other between both ends of the dc stage capacitor;
and an inductor connected between one end of the battery and a node of the upper-arm switching element and the lower-arm switching element. 13. The method of claim 12,
According to the ON of the lower-arm switching element, the energy of the battery is stored in the inductor, and according to the OFF of the lower-arm switching element and the ON of the upper-arm switching element, the energy of the inductor is transferred to the dc terminal capacitor Motor drive device, characterized in that. 13. The method of claim 12,
The inverter is
A motor driving device comprising two pairs of an upper-arm switching element and a lower-arm switching element. 15. The method of claim 14,
A power module comprising three pairs of upper-arm switching elements and lower-arm switching elements; further comprising,
A pair of upper-arm switching elements and lower-arm switching elements of the power module are included in the converter, and two pairs of upper-arm switching elements and lower-arm switching elements of the power module are included in the inverter. . battery;
a converter for converting and outputting DC power from the battery;
an inverter that converts the dc stage power into AC power by a switching operation and outputs the converted AC power to the motor;
a dc terminal capacitor connected between the converter and the inverter;
The converter is
an upper-arm switching element and a lower-arm switching element connected in series with each other between both ends of the dc stage capacitor;
and an inductor connected between one end of the battery and a node of the upper-arm switching element and the lower-arm switching element. 17. The method of claim 16,
According to the ON of the lower-arm switching element, the energy of the battery is stored in the inductor, and according to the OFF of the lower-arm switching element and the ON of the upper-arm switching element, the energy of the inductor is transferred to the dc terminal capacitor Motor drive device, characterized in that. 18. A home appliance comprising the motor drive device of any one of claims 1-17.

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