KR20140108956A - Power converting apparatus and air conditioner having the same - Google Patents

Abstract

Provided are a power converting apparatus, a controlling method thereof, and an air conditioner including the power converting apparatus, capable of minimizing a current supplied into a DC link capacitor by performing control such that a form of a current inputted to an inverter follows a form of an output current of a converter. Additionally, provided are a power converting apparatus which performs a converter control function based on a phase current restoration of a converter through inductor ripple current estimation, a controlling method thereof, and an air conditioner including the power converting apparatus. For this purpose, the power converting apparatus according to an embodiment comprises: a converter which converts an input AC voltage into a DC voltage; a DC link capacitor connected in parallel to the converter to generate a DC link voltage based on the DC voltage; an inverter which converts the DC link voltage of the DC link capacitor into a motor driving voltage according to a control signal and provides the motor driving voltage to a motor; and a control unit which generates the control signal. The control unit can generate the control signal such that the form of the inverter input current inputted to the inverter follows the form of the converter output current outputted from the converter.

Description

BACKGROUND OF THE INVENTION 1. Field of the Invention [0001] The present invention relates to a power conversion apparatus and an air conditioner including the power conversion apparatus.

The technique disclosed in this specification includes a power conversion device, a control method thereof, and a power conversion device capable of minimizing the current flowing into the DC link capacitor by controlling the shape of the current flowing into the inverter to follow the shape of the output current of the converter The present invention relates to an air conditioner.

Further, the technology disclosed in this specification relates to a power conversion apparatus that performs a converter control function based on phase current restoration of a converter through inductor ripple current estimation, a control method thereof, and an air conditioner including a power conversion apparatus.

Background Art [0002] In recent years, an air conditioner mainly uses a three-phase motor as a driving motor for a compressor. A three-phase motor power conversion device converts an alternating current, which is a commercial power source, into a direct current, and then drives the three-phase motor by applying the converted direct current to the three-phase motor using an inverter.

The air conditioner uses a motor such as a compressor and a fan, and uses a power conversion device for driving the motor. The power conversion apparatus converts the AC voltage supplied from the input power source into a DC voltage, converts the DC voltage into a pulse-width modulated (PWM) voltage, and supplies the DC voltage to the load.

On the other hand, as the air conditioner requires high performance and high efficiency, problems such as harmonic current, input power factor, and EMC arise. For example, when the harmonic current input to the input power source side and the input power factor characteristic are poor, other electric devices connected to the power system may malfunction and adversely affect the service life. For these reasons, countries are tightening regulations on power factor, harmonics, etc. to improve power quality.

Generally, a power conversion apparatus is connected in parallel between an input AC power source and a load, for example, a motor, and a converter and an inverter. At this time, a DC link capacitor is interposed between the converter and the inverter.

A typical power conversion device uses a converter (diode rectifier circuit) to obtain DC power from an AC power source, and then drives the motor using an inverter. This method is not able to regenerate the energy due to the characteristics of the converter, and thus a braking resistor is required. In order to absorb the instantaneous energy regenerated in the inverter, a large capacity electrolytic capacitor should be used as a DC link capacitor. An inverter using electrolytic capacitors is called a normal inverter. Electrolytic capacitors can increase not only their lifetime, but also the harmonics of the input supply current.

In order to suppress the harmonics of the input power supply current, a DC or AC reactor is further provided. As the capacity of the reactor increases, the cost and the volume and weight of the product increase.

In recent years, researches have been actively conducted on a power conversion device that performs power conversion using an inverter using a low capacity capacitor, that is, a so-called capacitorless inverter, without using a large capacity electrolytic capacitor as a DC link capacitor. Such an inverter has advantages in terms of price and volume as compared with a conventional inverter.

On the other hand, an inverter is a device which generates a variable voltage and a variable frequency AC power from a constant or variable DC power source. Because of the ease of energy saving and output control, a motor used in an electric appliance such as a washing machine, a refrigerator, A method of detecting a current applied to a motor and controlling the current applied to the motor by a pulse width modulation (PWM) method in order to efficiently control the motor using an inverter circuit, etc. Is used.

However, since the current flowing into the inverter and the output current of the converter are different from each other in general, there is a considerable amount of current flowing into the DC link capacitor, and the DC current flowing into the DC link capacitor There may be a problem that the size of the DC link capacitor can not be reduced due to the fluctuation of the link voltage. In particular, this problem can be highlighted in the above-described capacitorless inverter design.

The present invention relates to a power conversion device capable of minimizing the current flowing into a DC link capacitor by controlling the shape of the current flowing into the inverter to follow the shape of the output current of the converter, a control method thereof, and an air conditioning The purpose of this paper is to provide

It is also an object of the present invention to provide a power conversion apparatus that performs a converter control function based on phase current restoration of a converter through inductor ripple current estimation, a control method thereof, and an air conditioner including a power conversion apparatus.

According to an aspect of the present invention, there is provided a power conversion apparatus including: a converter for converting an input AC voltage into a DC voltage; A DC link capacitor connected in parallel to the converter and generating a DC link voltage based on the DC voltage; An inverter for converting the DC link voltage of the DC link capacitor into a motor drive voltage according to a control signal and supplying the DC link voltage to the motor; And a control unit for generating the control signal. The control unit may generate the control signal so that the type of the inverter input current flowing into the inverter tracks the shape of the converter output current output from the converter.

In one embodiment of the present invention, the controller may control the inverter such that the current value corresponding to the inverter input current falls within a certain range of the current value corresponding to the converter output current.

As an example related to the present specification, the predetermined range may be ± 5% of the converter output current value.

The control unit may include a speed controller for generating a reference inverter power for controlling the speed of the motor based on a reference angular speed, an angular speed corresponding to the motor, and an input angular speed corresponding to the input AC voltage, ; A power controller for generating a reference current based on the reference inverter power and the inverter power corresponding to the inverter; And a current controller for generating a reference voltage for controlling the current of the motor based on the reference current.

As an example related to the present specification, an input voltage sensor for detecting the input angular velocity may be further provided.

As an example related to the present specification, the speed controller may include a proportional integral controller (PI).

As an example associated with this disclosure, the power controller may include at least one of a proportional integral controller (PI), a weak field controller, and a maximum torque operating point per unit current (MTPA).

As an example related to the present specification, the power controller may generate the reference current based on the reference inverter power and the inverter power corresponding to the inverter.

As an example related to the present specification, the converter improves the power factor of the power supplied by the input AC voltage based on the switching operation by the converter control signal, and the control unit controls the input And to generate the converter control signal based on the current.

As an example related to the present specification, it may further include an input current sensor for detecting the input current.

As an example related to the present specification, the control unit may generate the converter control signal based on a fundamental wave component of the input current.

As an example related to the present specification, the converter may be an interleaved converter having two phases, and the control unit may generate a converter control signal corresponding to each phase of the interleaved converter.

The control unit may detect a fundamental wave component of the input current from the input current and output a fundamental wave component corresponding to each phase of the interleaved converter based on the fundamental wave component of the input current, And generates a converter control signal corresponding to each phase based on the fundamental wave component corresponding to the detected phase.

As one example related to the present specification, the converter includes: a switching device that is switched by the converter control signal; And a shunt resistor connected to the switching element, and the control unit may generate the converter control signal based on a current flowing on the converter detected based on the shunt resistor.

As an example related to the present specification, the converter is an interleaved converter in which two phases exist, and the control unit controls the phase of each of the phases on each phase of the interleaved converter based on a current flowing on each phase detected based on the shunt resistance To generate the corresponding converter control signal.

The control unit generates the converter control signal based on the input current when the turn-on time of the switching element is equal to or less than a reference time, and the control unit controls the turn- And if it exceeds the time, generates the converter control signal based on the current flowing in each phase detected based on the shunt resistance.

As an example related to the present specification, the reference time may be 2 [usec].

According to another aspect of the present invention, there is provided a power conversion apparatus for converting an input AC voltage to a DC voltage and improving a power factor of power supplied by the input AC voltage based on a switching operation by a converter control signal Converter; A DC link capacitor connected in parallel to the converter and generating a DC link voltage based on the DC voltage; An inverter for converting the DC link voltage into a load drive voltage and supplying the DC link voltage to the motor; And a controller for generating the converter control signal based on an input current supplied by the input AC voltage.

According to the power conversion apparatus according to the embodiment disclosed herein, the current flowing into the inverter is controlled so as to follow the shape of the output current of the converter, thereby minimizing the current flowing into the DC link capacitor. Thus, an efficient capacitorless inverter inverter may be provided.

1 is a block diagram illustrating a power conversion device according to one embodiment.
Figs. 2 to 3 are circuit diagrams showing details of examples of the converter in Fig. 1
4 is a block diagram showing a configuration of a three-phase motor control apparatus according to the present invention.
5 is a block diagram showing a configuration of a sine wave conduction system control unit in Fig.
6 is a block diagram showing a configuration of a square-wave-conduction-type control unit in Fig.
FIG. 7 is a graph showing measured values when a motor is driven by a sinusoidal energization method; FIG.
8 is a graph showing measured values when the motor is driven by a square wave energizing method;
9 is an exemplary view showing an example of a power conversion apparatus having an interleaving converter.
10 is an exemplary view showing a current flowing into the DC link capacitor.
11 is a configuration diagram showing a configuration of a power conversion apparatus according to an embodiment disclosed in this specification.
12 is a configuration diagram showing a configuration of a control unit according to an embodiment disclosed in this specification.
13 is an exemplary view showing a converter for controlling a switching element based on a current flowing on a converter detected through a shunt resistor.
14 is an exemplary diagram illustrating a power conversion apparatus according to an embodiment disclosed herein.
15 is an exemplary diagram illustrating a power conversion apparatus according to another embodiment disclosed herein.
16 is an exemplary diagram illustrating a method for detecting a phase current ripple value according to an embodiment disclosed herein.
17 is a view illustrating an example of an air conditioner including a power conversion apparatus according to embodiments of the present invention.

Although the technology disclosed in this specification describes only the air conditioner including the power conversion device, the power conversion device can be similarly used for other electric devices including a compressor and a motor.

It is noted that the technical terms used herein are used only to describe specific embodiments and are not intended to limit the scope of the technology disclosed herein. Also, the technical terms used herein should be interpreted as being generally understood by those skilled in the art to which the presently disclosed subject matter belongs, unless the context clearly dictates otherwise in this specification, Should not be construed in a broader sense, or interpreted in an oversimplified sense. In addition, when a technical term used in this specification is an erroneous technical term that does not accurately express the concept of the technology disclosed in this specification, it should be understood that technical terms which can be understood by a person skilled in the art are replaced. Also, the general terms used in the present specification should be interpreted in accordance with the predefined or prior context, and should not be construed as being excessively reduced in meaning.

Also, the singular forms "as used herein include plural referents unless the context clearly dictates otherwise. In this specification, the terms "comprising ", or" comprising "and the like should not be construed as necessarily including the various elements or steps described in the specification, Or may be further comprised of additional components or steps.

Furthermore, terms including ordinals such as first, second, etc. used in this specification can be used to describe various elements, but the elements should not be limited by the terms. The terms are used only for the purpose of distinguishing one component from another. For example, without departing from the scope of the present invention, the first component may be referred to as a second component, and similarly, the second component may also be referred to as a first component.

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS Hereinafter, embodiments of the present invention will be described in detail with reference to the accompanying drawings, wherein like reference numerals denote like or similar elements, and redundant description thereof will be omitted.

Further, in the description of the technology disclosed in this specification, a detailed description of related arts will be omitted if it is determined that the gist of the technology disclosed in this specification may be obscured. It is to be noted that the attached drawings are only for the purpose of easily understanding the concept of the technology disclosed in the present specification, and should not be construed as limiting the spirit of the technology by the attached drawings.

An air conditioner including a power conversion device according to embodiments of the present invention

17, an air conditioner including a power conversion device according to embodiments of the present invention includes a power conversion device as described below, a plurality of switching devices, and the DC power source An inverter for converting the voltage into a motor driving voltage and outputting it to the motor, and a compressor including a driving motor driven in accordance with the motor driving voltage.

Specifically, the air conditioner includes at least one indoor unit that performs air conditioning, a compressor that compresses the refrigerant at a high temperature and a high pressure, a motor that operates the compressor, and a controller that controls driving of the motor. In addition, the air conditioner includes an outdoor unit connected to at least one indoor unit through a pipe to drive the indoor unit. The control device includes a power conversion device according to the present invention, wherein the power conversion device includes at least one switching device for a power conversion device, and drives the switching device in accordance with a control signal to generate a return path, Compensate. Further, the power conversion apparatus includes a rectifying unit for rectifying the AC voltage of the commercial AC power source and converting the rectified AC voltage into a rectified voltage.

The outdoor unit 10 includes an evaporator 13 for heat-exchanging refrigerant compressed in the compressor with air, an expansion valve 14 for expanding the refrigerant discharged from the evaporator to low temperature and low pressure, And a refrigerant switching valve (17) provided at an outlet of the compressor (12) for guiding the refrigerant compressed in the compressor to the evaporator (13) or the condenser (15) do.

17, the outdoor unit 10 is provided with a refrigeration cycle including a compressor 12, an evaporator 13, an expansion valve 14 and a condenser 15 in a casing 11, A plurality of suction fans 16 for sucking outside air and exchanging heat with the evaporator 13 are installed on the upper surface or the side surface of the condenser 15 and a medium for supplying cold water or hot water to the indoor units 20 The circulation pipe 30 is connected. A refrigerant switching valve 17 is provided at the outlet of the compressor 12 for switching the refrigerant compressed by the compressor 12 to the direction of the evaporator or the direction of the condenser according to operating conditions.

The refrigerant switching valve 17 is normally a four-way valve. The outdoor unit 10 operates as a cooler during the summer season, while it operates as a heater during the winter season. For example, during the summer, the refrigerant compressed by the compressor 12 at high temperature and high pressure is guided to the evaporator 13 by the refrigerant switching valve, heat-exchanged with the air in the evaporator 13 to be radiated, And then the refrigerant is heat-exchanged with water in the condenser 15 to supply the heat-exchanged water to the indoor units 20 which use the refrigerant as a cooling heat source. Meanwhile, during the winter season, the refrigerant switching valve 17 guides the refrigerant in the direction of the condenser, and the high-temperature and high-pressure refrigerant is heat-exchanged with water in the condenser 15 and supplied to the indoor units 20 using the heat- do.

Description of power conversion device and converter structure included in it

1 is a block diagram illustrating a power conversion apparatus according to an embodiment.

Referring to FIG. 1, a power conversion apparatus according to an embodiment includes a converter 200, a DC link unit 300, and a controller 400. In addition, the power conversion apparatus may further include an inverter 500.

The converter 200 includes at least one switch, converts the input power source 100 into direct current power, and operates the switch in accordance with the converter control signal to improve the power factor. The DC link unit 300 is connected to the rear end of the converter 200. The inverter 500 includes a plurality of switching elements and converts the DC link voltage of the DC link part 300 into a motor driving voltage and outputs the voltage to the load (for example, the compressor motor 600). The control unit 400 generates an inverter control signal in a switching element in the inverter 500 and generates a converter control signal in the switch in the converter 200. [

FIGS. 2 to 3 are circuit diagrams showing the details of the examples of the converter in FIG.

Referring to FIG. 2, the converter 200 may be divided into a rectifying unit and a power factor improving unit. The rectification section rectifies the AC voltage of the input power supply 100. Further, the rectifying section and the power factor improving section share a diode bridge circuit. In order to perform full-wave rectification of the AC voltage supplied from the input power supply 100, a diode bridge circuit composed of four diodes is generally required. Of course, the power factor improving section further includes one or more switches.

The converter 200 operates the switch provided to improve the power factor of the input power source 100 according to the converter control signal. Specifically, the power factor of the input current can be improved by returning the current of the input power source by turning on the switch and storing the returned current in the connected reactor. Here, the switch may be, for example, an Insulated Gate Bipolar Transistor (IGBT), a MOSFET, or the like. The switch interrupts the return path of the input power supply 100 according to the converter control signal. That is, the switching operation of the switch is performed in accordance with the converter control signal so that the input power is returned.

The control unit 400 controls the path of the input power source 100 and the short-circuit conduction time through a switch provided in the converter 200. Here, the short-circuit conduction time can be appropriately selected according to the load or the power value of the input power source in order to rectify the waveform of the current. In addition, the controller 400 may detect a zero crossing point when connected to one end of the input power source. The control unit 400 generates a converter control signal to turn on the switch of the converter to generate a return path of the input power source 100. [ In addition, the control unit controls the short-circuit conduction time of the input power source 100 according to the magnitude of the detected load to improve the power factor.

A reactor 200a may be provided within the converter 200 as shown in Figure 3. The reactor removes the harmonic components and compensates for the power efficiency of the input power supply 100. [ When the switch of the converter 200 is turned on, the reactor stores the energy of the input power source 100 and short-circuits the input power source 100. That is, when the switch of the converter 200 is turned on according to the converter control signal of the control unit, a return path is formed, and the reactor stores the power of the input power source 100 and forcibly short-circuits the input power source 100.

Also, a noise filter (N / F) may be further included between the input power source 100 and the reactor or between the input power source 100 and the converter 200.

The DC link unit 300 smoothes the DC voltage rectified by the converter 200. The DC link unit 300 supplies a smooth DC voltage to a load, for example, an inverter and a rear stage. The DC link unit 300 may be composed of one capacitor (DC Link Capacitor) or a simple circuit including the same.

At this time, the control unit 400 may switch the switch of the converter so that the waveform of the input current of the input power source 100 follows the current slope determined by the power frequency and the peak value of the input current. The control unit 400 generates a converter control signal for switching the switch once or plural times based on the zero crossing point by twice the power source frequency of the input power source 100 to determine the waveform of the input current. The power converter uses data on the power consumption, input voltage, and DC link voltage of the load to determine the type of current that satisfies the power factor and harmonic regulation. The waveform of the input current follows the current slope determined by the power frequency and the peak value of the input current. The waveform of the input current is determined by at least one of a delay time of a certain time from the zero crossing point of the input voltage, a current slope, a current ripple due to switching, a switching frequency, and a DC link voltage.

FIG. 3 shows another example converter 200. FIG. Referring to FIG. 3, the converter 200 may be divided into a rectifier 210 and a power factor improving unit 220, as in FIG. However, the rectifying part and the power factor improving part do not share the bridge diode circuit. That is, the rectifying unit 210 is generally constituted by a bridge diode circuit, and the power factor improving unit 220 is constituted by an interleaved converter circuit.

The interleaved converter circuit controls the currents of the two phases and may delay the current phase of one phase to cancel the current ripples to reduce the input stage inductor and the input stage EMI filter.

It is also possible to add a shunt resistor under a switch (for example, an IGBT), to sense the current using the shunt resistor and to operate in a control part (for example, Micom) Switching signal) can be varied to perform current control.

Therefore, the interleaved converter circuit disclosed in FIG. 3 is also referred to as an interleaving Boost PFC (Power Factor Corrector).

In the case of the interleaved converter circuit, the current rating can be reduced to 1/2 as compared with the single-phase boost converter since it is two-phase.

The interleaving effect may also have the advantage of reducing the inductor volume at the same switching frequency.

The power factor improving unit 220 is composed of a pair of switches and a diode forming a current path. Freewheeling diodes can be connected to the switches. A reactor may be connected to the front ends of the switches. The switches constituting the power factor improving unit 220 operate complementarily. The detailed description thereof is the same as that of a general interleaved converter circuit, and the following description is omitted.

The power conversion apparatus may further include an input voltage detection unit (not shown) for detecting an input voltage of the input power source 100. The power conversion apparatus may further include a DC link voltage detection unit (not shown) for detecting a DC link voltage of the DC link unit 300.

According to the embodiment disclosed herein, the control unit 400 described above can perform a function of generating a converter control signal based on an input current supplied by an input AC voltage to be described later. To this end, the power conversion apparatus according to an embodiment may further include an input current sensor for detecting the input current. The control unit 400 detects a fundamental wave component of the input current from the input current, detects a fundamental wave component corresponding to each phase of the interleaved converter based on the fundamental wave component of the input current, A converter control signal corresponding to each phase can be generated on the basis of the fundamental wave component corresponding to the detected phase, and a converter control function can be performed by restoring phase current of the converter through inductor ripple current estimation.

Explanation of the power conversion device, the inverter structure included therein, and the inverter control method

Hereinafter, a power conversion device applied to a three-phase motor, an inverter structure included therein, and an inverter control method will be described with reference to FIGS. 4 to 8. FIG.

Referring to FIG. 4, the three-phase motor control apparatus according to the embodiment includes a converter 20 for rectifying the input AC power source 10 to a DC power source, And an inverter 40 for converting the DC power to a driving power based on a control signal and applying the DC power to the three-phase motor 100. The inverter 40 includes a DC link capacitor 30), and a control unit (50, or a control unit) for generating and outputting the inverter control signal. Here, various types of motors may be used as the three-phase motor 100. For example, a brushless DC motor (BLDC motor), an AC motor, or the like may be used. Hereinafter, a brushless motor can be described as a basic premise, but the same can be applied to other three-phase motors within a range not departing from the scope of the invention.

The converter 20 is connected to the input AC power supply 10 and rectifies the AC from the input AC power supply 10 to DC. The converter 20 generally includes a plurality of diodes, typically a diode bridge consisting of four diodes, to full-wave rectify the AC voltage of the AC power source by the diodes and convert it into a DC voltage.

The DC link capacitor 30 is connected in parallel to the output terminal of the converter 20 and applies a DC voltage, i.e., a DC link voltage, generated across the capacitor to the input terminal of the inverter 40. [ The DC link capacitor 30 smoothes the ripple voltage (voltage fluctuation) that occurs in response to the switching frequency while the switching elements in the inverter 40 switch. In addition, the DC link capacitor 30 can smooth the voltage that is rectified in accordance with the converter 20, that is, the voltage that fluctuates in accordance with the power supply voltage.

One end of the inverter 40 is connected in parallel to the DC link capacitor 30 and the other end is connected to the three-phase motor 100 to switch the output of the DC link capacitor 30 in accordance with the inverter control signal, Voltage, generally three-phase AC, and supplies it to the three-phase motor 100.

The control unit 50 includes at least a sine wave energizing method and a square wave energizing method. In addition, the control unit 50 generates a inverter control signal by selecting a sinusoidal wave energizing method or a square wave energizing method based on the speed command for the three-phase motor 100. [ The sine wave energizing method includes a space vector pulse width modulation (SVPWM) method, a discrete PWM (DPWM) method, and the like. In addition, the square-wave power-supply system is called a so-called 120-degree power-supply system.

Referring again to FIG. 4, the three-phase motor control apparatus further includes a drive current detection unit 60 that detects a drive current flowing from the inverter 40 to the three-phase motor 100. The control unit 50 can generate an inverter control signal for controlling the inverter by comparing the detected current with the command current. The drive current detection unit 60 may be a current transducer connected between the inverter 40 and the three-phase motor to continuously detect the motor drive current. The current transducer detects the motor drive current, converts it into a voltage signal, and outputs it to the control unit 50. The control unit 50 can generate an interrupt signal and sample the voltage signal according to the motor drive current. 4, the drive current detection unit 60 may be a shunt resistor connected in series to the switching element in the inverter 40. [ In FIG. 4, all three phases are connected (3p) to detect the driving current, but they may be connected (1p) to detect the driving current only in one phase.

In the case of controlling the three-phase motor by detecting the motor drive current, the control unit 50 can generally use the above sinusoidal wave electrification method. In the case of the sine wave energizing method, the control device senses the position of the electric angle using a sensorless algorithm, for example, a voltage equation, a magnetic flux equation, and an extended counter electromotive force equation using a motor driving current. Taking the SVPWM method, which is one of the sine wave energizing methods, as an example, a three-phase hexagonal vector diagram is used. In this case, current flows from one phase to another two phases or from two phases to another phase, and the duty changes of the three phase pulse width modulation are different from each other. The pulse width modulation duty according to the electric angle is changed for a constant output condition. As the phase angle control can be up to 90 degrees, the degree of freedom of control at high speed is high.

Referring to FIG. 5, the control unit 50 may include a sinusoidal wave conduction type control unit for controlling the inverter 40 in a sinusoidal conduction manner. The sinusoidal current conduction mode control unit includes a speed control unit 511 for receiving the speed command and the speed of the rotor and calculating and outputting a current command for reducing the speed error and a voltage control unit 511 for receiving the current command and the driving current, And a pulse width modulation controller 515 for generating the inverter control signal based on the voltage command. The sine wave conduction system control unit may further include an axial conversion unit 517 for converting the three phases into two phases of the dq axis. The sine wave conduction system control unit may further include a speed calculating unit 519 for calculating the rotor speed and outputting it to the speed control unit 511. [ FIG. 7 is a graph showing signal measurement values when a three-phase motor is driven by SVPWM, which is one of the sinusoidal energization methods. As shown in the figure, a drive current is detected to generate an inverter control signal, and a signal is output to the gates of the U, V, and W phases of the three-phase motor through the inverter. At this time, the graph of the phase current can have a sinusoidal waveform.

The speed control unit 511 includes a comparator for comparing the speed command? ^* _M desired by the user with the rotor speed, and a proportional integral controller (PI). The speed control unit 511 receives the speed command and the rotor speed and performs a proportional and integral calculation of the speed error to generate a q-axis current command (i ^* _q ) and output it to the current controller 513.

The current controller 513 receives the q-axis current command and the d-axis current command (i ^* _d ) generated by the speed controller 511 and generates and outputs a voltage command. The current control section 513 outputs the q-axis voltage command (V ^* _q ) to the pulse width modulation control section 515 via the current proportional integral controller and the filter through the q-axis current command. That is, the current controller 513 compares the q-axis detected current (i _q ) obtained by performing the axial conversion of the q-axis current command and the motor drive current through the axial conversion unit 517, and calculates the difference therebetween, And outputs the q-axis voltage command (V ^* _q ) to the pulse width modulation controller 515 via the controller and the filter. On the other hand, the current controller 513 outputs the d-axis voltage command V ^* _d to the pulse width modulation controller 515 via another current proportional integral controller and the d-axis current command. That is, the current control unit 513 compares the d-axis detected current i _d that is the axis-converted d-axis current command and the motor drive current and calculates the difference therebetween through the current proportional integral controller and the filter to the d- It is possible to output the command (V ^* _d ) to the pulse width modulation control section 515. [ Here, the voltages and currents are values on a synchronous coordinate system.

The pulse width modulation controller 515 first converts the voltage command of the synchronous coordinate system into the voltage command of the stationary coordinate system (?,?). That is, the pulse width modulation controller 515 converts (V ^* _d , V ^* _q ) into (V ^* _? , V ^* _? ). Further, the pulse width modulation controller 515 converts the voltage command of the stationary coordinate system to the motor type to be driven and outputs the converted voltage command. That is, the pulse width modulation control unit 515 can convert the voltage command in the stationary coordinate system into the three-phase voltage commands V ^* _u , V ^* _v , and V ^* _w and output it to the inverter 40.

Referring again to FIG. 4, the three-phase motor control apparatus further includes a drive voltage detection unit 70 for detecting a drive voltage applied to the three-phase motor 100 from the inverter 40. Although all of the three-phase driving voltages are shown as being detected, only one-phase driving voltages can be detected. In the case of controlling the three-phase motor by detecting the motor drive voltage, the control unit 50 generally uses the square-wave energizing method. In the case of the square wave energizing method, the control device detects a zero crossing point of the counter electromotive force appearing in the section not conducting with the phase voltage detection. The square-wave energizing method performs simple PWM on-duty control. That is, in the square-wave energizing method, current flows from 1 phase to 1 phase, and PWM switching is performed in only one phase, and the PWM duty variation according to the electric angle is constant at a constant output condition. The square-wave energizing method is advantageous for synchronous drive (operation) because it directly detects the electric angle position by the counter electromotive force.

Referring to FIG. 6, the control unit 50 may include a rectangular-wave power-supply-type control unit for controlling the inverter by the square-wave-current-supply method. The square wave conduction type control unit includes a duty controller 521 for calculating the duty of the inverter control signal that receives the speed command and the rotor speed and reduces the speed error, And a position detection unit 523.

The square wave conduction system control unit may further include a speed calculating unit 525 for calculating the rotor speed and outputting it to the duty controller 521. [ The square-wave-current-conduction-type control unit can output the inverter control signal for controlling the duty to the inverter 40 by setting the frequency of the driving current according to the speed command or the frequency command. 8 is a graph showing signal measured values when a three-phase motor is driven by a 120-degree energizing method which is one of square-wave energizing methods. 4, the waveform of the phase current has the form of a square wave. In some cases, gate signals are not applied to the U-phase gate. The control device detects the driving voltage and generates inverter control signals, and outputs signals to the gates of the U, V, and W phases of the three-phase motor through the inverter.

In the above description, the inverter is controlled by the sinusoidal wave current method using the drive current or the inverter is controlled by the square wave current method using the drive voltage. In the opposite case, that is, the drive current and the square wave current method And a drive voltage and a sinusoidal current conduction method may be used. In addition, the driving current detection unit and the driving voltage detection unit may be provided separately, but according to the technique disclosed in this specification, it is also possible to provide both detection units.

According to the embodiment disclosed herein, the control unit 50 (or the control unit) described above controls the speed of the motor based on the reference angular velocity, the angular velocity corresponding to the motor, and the input angular velocity corresponding to the input AC voltage A power controller for generating a reference current based on the reference inverter power and the inverter power corresponding to the inverter and a reference voltage for controlling the current of the motor based on the reference current, And a current control unit to generate a DC link capacitor, thereby minimizing the inrush current of the DC link capacitor through inverter current synchronization control.

Hereinafter, referring to FIGS. 9 to 16, a converter control function is performed based on the function of minimizing the inrush current of the DC link capacitor and / or restoring the phase current of the converter through inductor ripple current estimation according to the embodiments disclosed herein Will be described.

Description of a power conversion device having a function of minimizing the inrush current of a DC link capacitor

9 is an exemplary view showing an example of a power conversion apparatus having an interleaving converter.

Referring to FIG. 9, a control unit (not shown) for controlling an interleaved converter (or an interleaved converter) can independently control the converter side and the inverter side based on the DC link capacitor.

That is, the control unit controls the converter such that the harmonics regulation of the input current is satisfied, the required power factor correction is performed, and the fluctuation of the voltage (or the DC link voltage) applied to the DC link capacitor is minimized The interleaving converter can be controlled.

In this case, the controller may control the inverter to assume that there is no fluctuation of the DC link voltage, and to convert the DC link voltage into a motor drive voltage to be supplied to the motor.

According to the power conversion apparatus and the control method thereof disclosed in FIG. 9, since a converter and an inverter are respectively controlled based on a DC link capacitor, a current error may be required.

Here, Vin is the input voltage (or input AC voltage), Iin is the input current (or the input alternating current), Icon is the output current of the converter, Idc is the inrush current flowing into the DC link capacitor, May refer to the incoming input current.

10 is an exemplary view showing a current flowing into the DC link capacitor.

Referring to FIG. 10, according to the power conversion apparatus disclosed in FIG. 9, it can be seen that relatively large current ripple flows into the DC link capacitor because the current required by the converter is different from the current required by the inverter , The inrush current (Idc) of the DC link capacitor = the converter output current (Icon) - the inverter input current (Iinv))

Therefore, a DC link capacitor having a large current capacity (ripple) may be required to compensate the current error required by the converter and the inverter to be controlled, respectively.

In addition, since the inverter can be operated by the SVPWM method, there is a time when the 0 vector is applied. Therefore, a period in which the current becomes zero within one PWM PWM period of the inverter occurs, and a minimum DC link capacitor .

Also, the current flowing into the DC link capacitor causes the DC link voltage to fluctuate, resulting in degradation of the motor control performance, resulting in reduction in cooling capacity, vibration, and noise.

Thus, the techniques disclosed herein require the current required by the inverter to be equal to the type of current needed by the converter to minimize the current drawn into the DC link capacitor (or, ) We propose a power converter that controls converter and inverter synchronously.

Here, within a certain range, it may mean that the difference between the two currents is within ± 5%.

That is, if the form of the output current of the converter (the magnitude of each frequency component) is the same (or very similar) to the form of the inverter current consumption (the magnitude of each frequency component), the current entering the DC link capacitor is ideally 0 Or very close to 0) (i.e., if Icon - Iinv = 0, Idc = 0).

According to the technique disclosed in this specification, the amount of the current flowing into the DC link capacitor becomes small, so that it is possible to reduce the number or size (or the capacitance value) of the DC link capacitors required.

Possible control methods include a first method of allowing the output current type of the converter to follow the form of the inverter input current and a second method of allowing the input current type of the inverter to follow the form of the converter output current have.

Hereinafter, the second method will be described.

A power conversion apparatus having a function of minimizing an inrush current of a DC link capacitor according to an embodiment disclosed herein includes a converter for converting an input AC voltage into a DC voltage, a converter connected in parallel to the converter, An inverter for converting a DC link voltage of the DC link capacitor into a motor drive voltage according to a control signal and supplying the motor drive voltage to the motor, and a control unit for generating the control signal.

Here, the control unit may generate the control signal so that the type of the inverter input current flowing into the inverter tracks the shape of the converter output current output from the converter (i.e., the control unit generates the control signal The inverter can be controlled on the basis of the output voltage of the inverter.

According to an embodiment, the controller may control the inverter such that the current value corresponding to the inverter input current falls within a certain range of the current value corresponding to the converter output current.

Also, according to one embodiment, the predetermined range may be ± 5% of the converter output current value.

According to an embodiment of the present invention, the controller includes a speed controller for generating a reference inverter power for controlling a speed of the motor based on a reference angular speed, an angular speed corresponding to the motor, and an input angular speed corresponding to the input AC voltage, A power controller (or a power controller) for generating a reference current based on the reference inverter power and the inverter power corresponding to the inverter, and a reference voltage generator for controlling the current of the motor based on the reference current, (Or a power control section) that generates a current control signal.

According to an embodiment, the power conversion apparatus may further include an input voltage sensor for detecting the input angular velocity.

Further, according to one embodiment, the speed controller may include a PI controller.

Also, according to one embodiment, the power controller may include at least one of a proportional integral controller (PI), a weak field controller, and a maximum torque operating point per unit current (MTPA).

According to an embodiment, the power controller may generate the reference current based on the reference inverter power and the inverter power corresponding to the inverter.

11 is a configuration diagram showing a configuration of a power conversion apparatus according to an embodiment disclosed in this specification.

Referring to FIG. 11, a power conversion apparatus (PCU) according to an embodiment disclosed herein may include a converter CVR100, a DC link capacitor DC100, an inverter INV100, and a controller C100.

A motor (LOAD, M) which is a load may be connected to the power conversion unit (PCU).

The converter CVR100 may serve to convert an input AC voltage into a DC voltage. In addition, the functions of the converter CVR100 are similar to those of the converters described above, so a detailed description thereof will be omitted.

The DC link capacitor DC100 is connected to the converter CVR100 in parallel, and can generate a DC link voltage based on the DC voltage. In addition, since the DC link capacitor DC100 is similar to the DC link capacitors described above, a detailed description thereof will be omitted.

The inverter INV100 may convert the DC link voltage of the DC link capacitor DC100 into a motor drive voltage and supply the DC link voltage to the motor LOAD according to a control signal. In addition, since the inverter INV100 is similar to the inverters described above, a detailed description thereof will be omitted.

The controller C100 basically generates the control signal and controls the inverter INV100.

According to one embodiment, the controller C100 may generate the control signal so that the shape of the input current Iinv of the inverter INV100 follows the shape of the output current Icon of the converter CVR100.

Thus, the input current Iinv of the inverter INV100 is equal to or similar to the output current Icon of the converter CVR100, so that the DC link current flowing into the DC link capacitor DC100 is reduced .

In this case, as described above, the number and size of the DC link capacitors can be reduced, and a capacitorless inverter having excellent performance can be realized.

Also, the controller C100 may control the inverter such that the current value corresponding to the inverter input current falls within a certain range of the current value corresponding to the converter output current.

Here, the predetermined range may be ± 5% of the converter output current value.

12 is a configuration diagram showing a configuration of a control unit according to an embodiment disclosed in this specification.

According to one embodiment disclosed herein, the controller C100 may include a speed controller SC100 and a power controller PC100.

The controller C100 may further include a current controller (not shown).

)을 생성할 수 있다.The speed controller SC100 includes a reference inverter power control unit for controlling the speed of the motor based on a reference angular speed wm *, an angular speed wm corresponding to the motor, and an input angular speed win corresponding to the input AC voltage, (

Can be generated.

The power conversion unit PCU may further include an input voltage sensor (not shown) for detecting the input angular speed win.

According to one embodiment, the speed controller SC100 may include a proportional integral controller PI (see FIG. 12).

) 및 상기 인버터에 해당하는 인버터 전력(

)을 근거로 기준 전류(

,

)를 생성할 수 있다. The power controller (PC 100) compares the reference inverter power (

) And the inverter power corresponding to the inverter (

) Based on the reference current (

,

Can be generated.

) 및 q축 기준 전류(

)를 포함할 수 있다.Here, the reference current is a d-axis reference current (

) And q-axis reference current (

).

)은 d축 전압 및 전류(

,

), q축 전압 및 전류(

,

)를 근거로 검출되는 것일 수 있다.(예를 들어,

)Further, the inverter power (

) Is the d-axis voltage and current (

,

), q-axis voltage and current (

,

) (For example,

)

Here, e may be a synchronous coordinate system.

According to one embodiment, the power controller PC 100 may include at least one of a proportional integral controller (PI controller), a weak field controller, and a maximum torque operating point per unit current (MTPA).

The weak field controller is a controller used when driving the motor in the weak field region. In the case of a normal inverter using a large-capacity electrolytic capacitor, weak field control is implemented as a feedback loop. In the case of a capacitorless inverter, an open loop is implemented for fast operation. .

When weak field control is performed, it is possible to widen the controllable section by adding the d-axis current to the proper magnitude in the minus direction.

In addition, the weak field controller may perform semantics, functions, and roles commonly known in the art. A detailed description thereof will be omitted.

) 및 상기 인버터 전력(

)을 근거로 단위 전류당 최대 토크 운전점(MTPA)을 산출할 수 있다.Wherein the maximum torque operating point per unit current (MTPA)

) And the inverter power (

), The maximum torque operating point (MTPA) per unit current can be calculated.

In addition, the maximum torque operation point per unit current (MTPA) may perform a function, a role, and the like generally known in the art. A detailed description thereof will be omitted.

,

)를 근거로 상기 모터의 전류를 제어하기 위한 기준 전압을 생성하는 역할을 할 수 있다.The current controller may control the reference current

,

And a reference voltage for controlling the current of the motor.

In addition, since the role and function of the current controller are similar to those of the current controller described above, a detailed description thereof will be omitted.

,

)를 생성하여 상기 인버터(INV100)를 제어하기 때문에 상기 인버터 입력 전류(Iinv)의 형태는 상기 컨버터 출력 전류(Icon)의 형태를 추종할 수 있게 될 수 있다.Consequently, the control unit C100 determines the reference current (I) based on the input angular speed (win)

,

To control the inverter INV100 so that the form of the inverter input current Iinv can follow the form of the converter output current Icon.

Inductor ripple  Of the converter through current estimation Phase current  Description of a power conversion device that performs converter control functions based on restoration

Hereinafter, a power conversion apparatus that performs a converter control function based on phase current restoration of a converter through inductor ripple current estimation according to an embodiment disclosed herein will be described with reference to FIGS. 13 to 16. FIG.

The power conversion apparatus performing the converter control function based on the phase current restoration of the converter through the inductor ripple current estimation according to the embodiment disclosed herein may be implemented as a part or a combination of the configurations or steps included in the embodiments described above Or a combination of the embodiments. In order to clearly express the power conversion apparatus performing the converter control function based on the phase current restoration of the converter through the inductor ripple current estimation according to the embodiment disclosed herein, Can be omitted.

A power converter according to an embodiment disclosed herein includes a converter that converts an input AC voltage to a DC voltage and improves a power factor of power supplied by the input AC voltage based on a switching operation by a converter control signal, A DC link capacitor connected in parallel to the converter for generating a DC link voltage based on the DC voltage and an inverter for converting the DC link voltage into a load drive voltage and supplying the same to a motor, And a control unit for generating the converter control signal based on the control signal.

According to one embodiment, the power conversion apparatus may further include an input current sensor for detecting the input current.

According to an embodiment, the control unit may generate the converter control signal based on a fundamental wave component of the input current.

According to an embodiment of the present invention, the converter is an interleaved converter having two phases, and the controller can generate a converter control signal corresponding to each phase of the interleaved converter.

According to an embodiment of the present invention, the control unit detects a fundamental wave component of the input current from the input current, and generates a fundamental wave component corresponding to each phase of the interleaved converter based on the fundamental wave component of the input current And generates a converter control signal corresponding to each phase based on the fundamental wave component corresponding to the detected phase.

According to an embodiment, the converter may include a switching element that is switched by the converter control signal and a shunt resistor connected to the switching element.

In this case, the controller may generate the converter control signal based on the current flowing on the converter detected based on the shunt resistor.

According to an embodiment of the present invention, the converter is an interleaved converter having two phases, and the control unit controls the phase of each of the phases on the phase of the interleaved converter based on a current flowing on each phase detected based on the shunt resistor. The corresponding converter control signal can be generated.

According to still another embodiment of the present invention, the controller generates the converter control signal based on the input current when the turn-on time of the switching element is equal to or less than a reference time, and when the turn- If the time is exceeded, the converter control signal can be generated based on the currents flowing on each phase detected based on the shunt resistance.

Further, according to one embodiment, the reference time may be 2 [usec].

13 is an exemplary view showing a converter for controlling a switching element based on a current flowing on a converter detected through a shunt resistor.

Referring to FIG. 13, the power conversion apparatus includes the structure of the above-described interleaved converter.

The power conversion apparatus further includes switching elements S1 and S2, a shunt resistor connected to the switching elements S1 and S2 and converter control signals Sgate_a and Sgate_b applied to the switching elements, And a control unit C200 for generating the control signal.

The power conversion apparatus may further include amplifiers A100 and A200 amplifying a current flowing on the converter detected by the shunt resistor and providing the amplified current to the controller C200.

The power converter (or the control unit C200) can select the command of the converter phase current so that the current DC link voltage becomes the target DC link voltage.

The power converter (or controller C200) compares the command of each phase current with the current value of each phase current read through the shunt resistor and outputs a gate signal (or converter) (Or generate) the control signal, Sgate_a, Sgate_b.

Vsh_a is a shunt voltage, Vsh_b is a b-phase shunt voltage, is is an input current (or input alternating current), iph_a is a phase current, and iph_b is a b-phase current. It can mean.

According to the power conversion apparatus disclosed in Fig. 13, the current of each phase is sensed (or detected) by using the shunt resistor under the switching elements S1 and S2, so that only when the switch is turned on, can do.

In this case, when the turn-on time of the switching elements S1 and S2 is shorter than the sensing time of the control unit C200 (for example, Micom or the like), a current may not be sensed.

That is, if the turn-on time of the switching elements S1 and S2 is not secured for more than the reference time (for example, 2 [usec]), there is a problem that the current can not be recognized as flowing even though the phase current flows .

The technique disclosed in this specification is based on Kirchhoff's current law. The input current includes a component of a current flowing to each phase, and the gate current (switching turn-on time, duty ratio) The harmonic component of the fundamental wave component is removed.

That is, the power conversion apparatus according to an embodiment disclosed herein estimates a current flowing to each phase by using a fundamental wave component of an input current, and based on the fundamental wave component corresponding to the estimated phase, It is possible to generate an accurate converter control signal irrespective of the turn-on time of the switching device.

14 is an exemplary diagram illustrating a power conversion apparatus according to an embodiment disclosed herein.

14, a power conversion apparatus according to an embodiment disclosed herein converts an input AC voltage to a DC voltage and calculates a power factor of the power supplied by the input AC voltage based on a switching operation by the converter control signal A DC link capacitor (Cdc) connected in parallel to the converter to generate a DC link voltage based on the DC voltage, an inverter (not shown) for converting the DC link voltage into a load drive voltage and supplying the DC link voltage to the motor And a controller C300 for generating the converter control signal based on the input current supplied by the input AC voltage.

Here, Vs may be an input voltage (or input AC voltage), is is an input current (or input AC current), iph_a is a phase current, iph_b is a b phase current, and CT is an input current sensor.

The role functions of the converter, the DC link capacitor Cdc, and the inverter are similar to those described above, and a detailed description thereof will be omitted.

According to one embodiment, the power conversion apparatus may further include an input current sensor (CT) for detecting the input current. The input current sensor CT may be implemented in various ways. For example, the input current sensor CT may be implemented as a current transducer.

The converter disclosed in Fig. 14 may be an interleaved converter in which two phases (a phase, b phase) exist.

In this case, the controller C300 may generate the converter control signals Sgate_a and Sgate_b corresponding to the respective phases of the interleaved converter.

According to one embodiment, the control unit C300 detects a fundamental wave component of the input current from the input current, and calculates a fundamental wave component corresponding to each phase of the interleaved converter based on the fundamental wave component of the input current And generates converter control signals Sgate_a and Sgate_b corresponding to the respective phases based on the fundamental wave components corresponding to the detected phases.

Specifically, the method of detecting the fundamental wave component corresponding to each phase will be described. First, since the input current Is is the sum of the currents flowing through each phase, it can be expressed by the following equation (1).

Likewise, Is_1, which is the fundamental wave component of the input current, is also the sum of the fundamental wave components of each phase and can be expressed by the following equation (2).

Here, Is_1, which is a fundamental wave component, can be expressed by Equation (3) as it is necessary to subtract the ripple current from the input current Is.

이므로The currents of the respective phases are similar to each other

Because of

The fundamental wave component of each phase can be expressed by the following equation (4).

As a result, the phase current ripple value according to the input current and duty can be calculated to restore (or detect) the phase current fundamental wave component.

Here, the term after Equation (4) means the sum of the ripple current components of each phase and may correspond to the ripple value of the phase current.

15 is an exemplary diagram illustrating a power conversion apparatus according to another embodiment disclosed herein.

15, a power conversion apparatus according to another embodiment disclosed herein includes a shunt connected to switching elements S1 and S2 existing in respective phases (a and b phases) of the interleaved converter, And a controller C400 for generating a converter control signal Sgate_a, Sgate_b in the switching element.

The power conversion apparatus may further include amplifying units A100 and A200 for amplifying a current flowing on each of the converters detected by the shunt resistor and providing the amplified current to the controller C400.

That is, the power conversion apparatus disclosed in Fig. 15 further includes, in addition to the power conversion apparatus disclosed in Fig. 14 (having a function of generating a converter control signal based on the input current), based on the current flowing on the converter And a function of generating the converter control signal may be additionally provided.

Here, Vs is an input voltage (or input AC voltage), Vsh_a is a-phase shunt voltage, Vsh_b is a b-phase shunt voltage, is is an input current (or input AC current), iph_a is a- CT may refer to an input current sensor.

15 shows a case where the converter is an interleaved converter having two phases, and the controller C400 controls the phases of the interleaved converters based on the currents flowing on the respective phases detected based on the shunt resistors To generate the corresponding converter control signal.

According to one embodiment, the controller generates the converter control signal based on the input current when the turn-on time of the switching elements S1 and S2 is equal to or less than a reference time, and the switching elements S1 and S2 ) Of the shunt resistor exceeds the reference time, the converter control signal may be generated based on the current flowing in each phase detected based on the shunt resistor.

Here, the reference time may be 2 [usec].

That is, when the turn-on time of the switching elements S1 and S2 is equal to or less than the reference time (the first case) based on the reference time, Controls the converter and controls the converter based on the current on the converter detected by the shunt resistor when the turn-on time of the switching elements (S1, S2) exceeds the reference time (second case) Function can be provided.

The turn-on time of the switching elements S1 and S2 may be determined by the converter PWM period Tcarrier and the PWM duty.

으로 결정될 수 있고, 상기 스위칭 소자(S1, S2)의 턴-온 시간은

로 결정될 수 있다.That is, the PWM duty (D, duty)

, And the turn-on time of the switching elements (S1, S2) may be determined as

. ≪ / RTI >

값이 상기 기준 시간(예를 들어, 2 usec) 보다 작은 경우 상기 제 1 경우에 해당하고, 반대인 경우, 상기 제 2 경우에 해당할 수 있다.therefore,

Corresponds to the first case when the value is smaller than the reference time (for example, 2 usec), and corresponds to the second case when the value is opposite.

As described above, in order to detect the fundamental wave component of the input current, it may be necessary to detect the phase current ripple value Is.

16 is an exemplary diagram illustrating a method for detecting a phase current ripple value according to an embodiment disclosed herein.

16 (a) shows a method of detecting the phase current ripple value when the duty value of the PWM signal is 0.5 or less.

According to Fig. 16 (a), the phase current ripple value? Is can be determined by the following equation (5).

16 (b) shows a method of detecting the phase current ripple value when the duty value of the PWM signal is 0.5 or more.

According to Fig. 16 (g), the phase current ripple value? Is can be determined by the following Equation (6).

Here, L is the inductance value of the reactor, Vs is the input AC voltage, VDC is the DC link voltage, D is the duty of the PWM signal, Ts is the period corresponding to the PWM signal or the input power source (input voltage or input current).

The scope of the present invention is not limited to the embodiments disclosed herein, and the present invention can be modified, changed, or improved in various forms within the scope of the present invention and the claims.

Vin: Input power CVR100: Converter
INV100: Inverter DC100: DC link capacitor
C100: Control section LOAD: Motor or load

Claims (17)

A converter for converting an input AC voltage into a DC voltage;
A DC link capacitor connected in parallel to the converter and generating a DC link voltage based on the DC voltage;
An inverter for converting the DC link voltage of the DC link capacitor into a motor drive voltage according to a control signal and supplying the DC link voltage to the motor; And
And a control unit for generating the control signal,
Wherein,
Wherein the control signal generating unit generates the control signal so that the form of the inverter input current flowing into the inverter follows the form of the converter output current output from the converter. The apparatus of claim 1,
And controls the inverter such that the current value corresponding to the inverter input current falls within a certain range of the current value corresponding to the converter output current. 3. The method according to claim 2,
The current value being ± 5% of the converter output current value. The apparatus of claim 1,
A speed controller for generating a reference inverter power for controlling the speed of the motor based on a reference angular speed, an angular speed corresponding to the motor, and an input angular speed corresponding to the input ac voltage;
A power controller for generating a reference current based on the reference inverter power and the inverter power corresponding to the inverter; And
And a current controller for generating a reference voltage for controlling the current of the motor based on the reference current. 5. The method of claim 4,
Further comprising an input voltage sensor for detecting the input angular velocity. 5. The apparatus of claim 4,
And a proportional integral controller (PI). 5. The apparatus of claim 4, wherein the power controller comprises:
A proportional integral controller (PI), a weak field controller, and a maximum torque operating point per unit current (MTPA). 5. The apparatus of claim 4, wherein the power controller comprises:
And generates the reference current based on the reference inverter power and the inverter power corresponding to the inverter. 2. The apparatus of claim 1,
The power factor of the power supplied by the input AC voltage is improved based on the switching operation by the converter control signal,
Wherein,
And generates the converter control signal based on the input current supplied by the input AC voltage. 10. The method of claim 9,
Further comprising an input current sensor for detecting the input current. 10. The apparatus according to claim 9,
And generates the converter control signal based on the fundamental wave component of the input current. 10. The converter of claim 9,
Lt; / RTI > is an interleaved converter in which two phases exist,
Wherein,
And generates a converter control signal corresponding to each phase of the interleaved converter. [12] The apparatus of claim 12,
Detecting a fundamental wave component of the input current from the input current,
Detecting a fundamental wave component corresponding to each phase of the interleaved converter based on the fundamental wave component of the input current,
And generates a converter control signal corresponding to each phase on the basis of the fundamental wave component corresponding to each of the detected phases. 10. The converter of claim 9,
A switching element for performing switching operation by the converter control signal; And
And a shunt resistor connected to the switching element,
Wherein,
And generates the converter control signal based on the current flowing on the converter detected based on the shunt resistor. 15. The apparatus of claim 14,
Lt; / RTI > is an interleaved converter in which two phases exist,
Wherein,
And generates a converter control signal corresponding to each phase of the interleaved converter based on a current flowing in each phase detected based on the shunt resistor. 16. The apparatus of claim 15,
The converter control signal is generated based on the input current when the turn-on time of the switching element is equal to or less than a reference time,
And when the turn-on time of the switching element exceeds a reference time, generates the converter control signal based on a current flowing in each phase detected based on the shunt resistor. 17. The method of claim 16,
2 < / RTI > [usec].

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