JP2019122120A - Inverter device, booster circuit control method, and program - Google Patents

Abstract

To reduce the possibility of step-out at the time of switching between full wave rectification and voltage doubler rectification even when field weakening control is not performed.SOLUTION: An inverter device includes a booster circuit that supplies, to an inverter circuit that supplies power to a motor, any one DC voltage of a single DC voltage, a doubled DC voltage corresponding to twice the single DC voltage, and an intermediate voltage which is an intermediate voltage between the single and doubled DC voltages, and a booster circuit control unit that controls the booster circuit to supply the doubled DC voltage after having supplied the intermediate voltage from the state where the booster circuit supplies the single DC voltage to the inverter circuit.SELECTED DRAWING: Figure 1

Description

  The present invention relates to an inverter device, a booster circuit control method, and a program.

  In relation to power supply to the motor, the motor control device described in Patent Document 1 includes full-wave rectification and voltage doubler rectification that generates a voltage twice as high as that obtained by full-wave rectification and supplies it to the motor. Switch to supply voltage to the motor. Further, the motor control device described in Patent Document 1 performs field weakening control when the motor voltage exceeds a predetermined value, and switches between full wave rectification and voltage doubler rectification based on the current value of field weakening control. On the other hand, the motor control device described in Patent Document 1 does not perform field weakening control in a region where the operation becomes unstable, and full wave based on the modulation factor indicating the relationship between the voltage necessary for motor input and the voltage of the smoothing capacitor. Switch between rectification and voltage doubler rectification.

JP 2011-234466 A

In the motor control device described in Patent Document 1, switching between full-wave rectification and voltage doubler rectification is performed without field weakening control in a region where operation becomes unstable in order to avoid abnormal stop such as step out. , Avoid switching during field weakening control.
On the other hand, even in the case where field weakening control is not performed, it is preferable that the possibility of step-out at the time of switching between full wave rectification and voltage doubler rectification can be reduced.

  The present invention provides an inverter device, a booster circuit control method, and a program capable of reducing the possibility of step-out at the time of switching between full-wave rectification and voltage doubler rectification even when field weakening control is not performed.

  According to the first aspect of the present invention, the inverter device is a doubled DC voltage equivalent to a single-voltage DC voltage and a doubled DC voltage with respect to the inverter circuit for supplying power to the motor. And a booster circuit for supplying a DC voltage of any one of an intermediate voltage which is an intermediate voltage between the first and second DC voltages and the booster circuit includes the first DC voltage. And a booster circuit control unit configured to control the booster circuit so as to supply the doubled DC voltage after supplying the intermediate voltage from the state of supplying the inverter circuit.

  The booster circuit control unit is configured to supply the intermediate voltage from the state where the booster circuit supplies the doubled DC voltage to the inverter circuit, and then supply the one-fold DC voltage. May be controlled.

  The booster circuit is a circuit that connects a positive electrode side capacitor and a negative electrode side capacitor connected in series with the inverter, and both ends of a rectifier circuit that is a voltage supply source to both ends of the negative electrode side capacitor by being turned on by itself. And a negative side switching element forming a circuit connecting both ends of the rectifier circuit and both ends of the positive electrode side capacitor by being turned on by itself; The booster circuit supplies the intermediate voltage by repeating switching on / off of any one of the positive side switching element and the negative side switching element and turning off the other switching element. Control, and any one switch of the positive side switching element and the negative side switching element On a result other switching elements so is turned off, by repeating the switching of the on / off switching elements, the booster circuit may be controlled to provide the double 圧直 current voltage.

  According to the second aspect of the present invention, the step-up circuit control method is a doubled voltage corresponding to a single-folded DC voltage and twice the single-folded DC voltage with respect to an inverter circuit for supplying power to a motor. A booster circuit for supplying any one of a DC voltage and an intermediate voltage which is an intermediate voltage between the first and second DC voltages and the inverter circuit is configured to supply the first DC voltage to the inverter circuit. Controlling the booster circuit to supply the doubled DC voltage after supplying the intermediate voltage.

  According to the third aspect of the present invention, the program includes, for an inverter circuit for supplying electric power to the motor, a single-voltage DC voltage and a double-voltage DC voltage corresponding to twice the single-voltage DC voltage. A computer for controlling a boosting circuit for supplying a DC voltage of any one of an intermediate voltage which is an intermediate voltage between the DC doubled voltage and the DC doubled DC voltage, the inverter The program is for controlling the booster circuit so as to supply the doubled DC voltage after supplying the intermediate voltage from the state of supplying to the circuit.

  According to the above-described inverter device, step-up circuit control method, and program, even when field weakening control is not performed, the possibility of step-out at the time of switching between full-wave rectification and voltage doubler rectification can be reduced.

It is a figure showing the circuit composition of the inverter device concerning this embodiment. FIG. 7 is a schematic block diagram showing a functional configuration of a booster circuit control unit according to the same embodiment. It is a figure which shows the example of on / off of the positive electrode side switching element in the single voltage double mode in the same embodiment, and a negative electrode side switching element. It is a figure which shows the example of on / off of the positive electrode side switching element in the intermediate voltage mode in the embodiment, and a negative electrode side switching element. It is a figure which shows the example of on / off of the positive electrode side switching element in 2 double pressure mode in the embodiment, and a negative electrode side switching element. It is a figure which shows the example of the value of the DC voltage in the case of switching from a 1 voltage boosting mode to an intermediate voltage mode and a 2 voltage boosting mode by the same embodiment. It is a figure which shows the example of the value of DC voltage in the case of switching from a 2 voltage doubling mode to an intermediate voltage mode and a 1st voltage boosting mode by the embodiment.

  Hereinafter, although the embodiment of the present invention is described, the following embodiment does not limit the invention concerning a claim. Moreover, not all combinations of features described in the embodiments are essential to the solution of the invention.

(Circuit configuration of inverter device)
FIG. 1 is a diagram showing a circuit configuration of the inverter device according to the present embodiment.
The inverter device 1 is mounted on an outdoor unit of an air conditioner (air conditioner) 90. Inverter device 1 outputs a load driving AC voltage (three-phase AC voltage) according to a separately input rotational speed command to a three-phase AC motor (motor 4) for driving the compressor of the outdoor unit. Do. The inverter device 1 rotationally drives the three-phase AC motor (motor 4), which is a load, at a desired number of revolutions, based on the load driving AC voltage.
The inverter device 1 converts the three-phase AC voltage supplied from the three-phase AC power supply 3 which is a commercial power source into the load driving AC voltage and outputs it. Here, the three-phase AC power supply 3 is, for example, an AC voltage of 200 V AC (effective value 200 V) and a frequency of 50 Hz (or 60 Hz), and three phases consisting of R phase, S phase, and T phase different from each other by 120 °. Output the AC voltage of the phase. Hereinafter, the AC voltage of each phase which the three-phase AC power supply 3 outputs is also described as “R-phase AC voltage”, “S-phase AC voltage”, and “T-phase AC voltage”, respectively.

  As shown in FIG. 1, the inverter device 1 includes a three-phase voltage doubler rectifier circuit 1A, an inverter circuit 20, an inverter circuit control unit 21, and a rotation number detection unit 13.

The three-phase voltage doubler rectifier circuit 1A rectifies the three-phase AC voltage supplied from the three-phase AC power supply 3 and outputs "DC voltage Vdc". The DC voltage Vdc which is the output voltage of the three-phase voltage doubler rectifier circuit 1A is output between the positive output terminal Qa and the negative output terminal Qb shown in FIG.
The three-phase voltage doubler rectifier circuit 1A according to this embodiment has a function as a voltage doubler rectifier circuit that outputs a voltage doubled with the maximum value of the input three-phase AC voltage, as described later.

The inverter circuit 20 converts the DC voltage Vdc output from the three-phase voltage doubler rectifier circuit 1A into a load driving AC voltage for driving the motor 4 to rotate. The inverter circuit 20 includes three pairs of two switching elements connected in series between the positive output terminal Qa and the negative output terminal Qb. Here, the switching element is, for example, a power transistor such as an insulated gate bipolar transistor (IGBT). Each pair of switching elements connected in series is provided corresponding to each of three phases for rotationally driving a three-phase AC motor (motor 4).
The inverter circuit 20 further includes a motor current detection unit 22.
The motor current detection unit 22 detects a current (motor current) to be returned to the three-phase voltage doubler rectifier circuit 1A. The motor current detection unit 22 outputs the detection result of the detected motor current to the inverter circuit control unit 21 as a detection signal.

The inverter circuit control unit 21 is a control IC (a so-called microcomputer or the like) that controls on / off of each switching element constituting the inverter circuit 20.
The rotation number command is input to the inverter circuit control unit 21 from the host device. The inverter circuit control unit 21 receives a detection signal of the motor current from the motor current detection unit 22.
While monitoring the motor current, the inverter circuit control unit 21 drives the inverter circuit 20 so that the rotational speed of the motor 4 becomes the rotational speed indicated by the rotational speed command. Here, the inverter circuit control unit 21 controls the inverter circuit 20 based on generally known PWM (Pulse Width Modulation) control.

(Configuration of three-phase voltage doubler circuit)
The circuit configuration of the three-phase voltage doubler rectifier circuit 1A will be described in detail.
As shown in FIG. 1, the three-phase voltage doubler rectifier circuit 1A includes a rectifier circuit 10, a booster circuit 11, a booster circuit control unit 12, and a reactor L.

The rectifier circuit 10 rectifies the three-phase AC voltage supplied from the three-phase AC power supply 3 and outputs it as a rectified voltage Vac.
Under control of the booster circuit controller 12, the booster circuit 11 can output a voltage twice as high as the maximum value of the three-phase AC voltage input from the three-phase AC power supply 3 as a DC voltage Vdc.
The booster circuit control unit 12 is a control IC that controls the booster circuit 11. The specific functional configuration of the booster circuit control unit 12 will be described later.
The rectifier circuit 10 and the booster circuit 11 are connected to each other on the positive electrode side via the reactor L by the positive electrode output line α. The rectifier circuit 10 and the booster circuit 11 are connected to each other on the negative electrode side by the negative electrode output line β.

The reactor L smoothes the current flowing to the positive electrode output line α.
In the following description, the positive electrode output line α is a line in which the first positive electrode output line α1 and the second positive electrode output line α2 are connected in series via the reactor L.
Therefore, the rectifier circuit 10 outputs the rectified voltage Vac between the first positive electrode output line α1 and the negative electrode output line β.

(Rectification circuit configuration)
The rectifier circuit 10 will be described in detail.
The rectifier circuit 10 has three input terminals (R-phase input) corresponding to each phase of three-phase AC voltages (R-phase AC voltage, S-phase AC voltage and T-phase AC voltage) supplied from the three-phase AC power supply 3 Input from each of the terminal QR, the S-phase input terminal QS, and the T-phase input terminal QT) and rectified.

Each of the R-phase AC voltage, the S-phase AC voltage, and the T-phase AC voltage oscillates with a period Tc while being out of phase with each other by 120 °.
The rectifying circuit 10 includes six rectifying diodes (positive side R-phase rectifying diode 10Ra, negative side R-phase rectifying diode 10Rb, positive side S-phase rectifying diode 10Sa, negative side S-phase rectifying diode 10Sb, positive side T-phase rectifying diode 10Ta and It is comprised by negative electrode side T phase rectification diode 10Tb).

  The positive side R-phase rectifier diode 10Ra and the negative side R-phase rectifier diode 10Rb of the rectifier circuit 10 rectify the R-phase AC voltage input from the three-phase AC power supply 3 through the R-phase input terminal QR. Specifically, the positive side R phase rectifier diode 10Ra is connected in the forward direction from the R phase input terminal QR to the first positive output line α1. The negative electrode side R phase rectification diode 10Rb is connected in the forward direction from the negative electrode output line β to the R phase input terminal QR.

  The positive side S-phase rectifier diode 10Sa and the negative side S-phase rectifier diode 10Sb of the rectifier circuit 10 rectify the S-phase AC voltage input from the three-phase AC power supply 3 through the S-phase input terminal QS. Specifically, the positive side S-phase rectifying diode 10Sa is connected in the forward direction from the S-phase input terminal QS to the first positive output line α1. The negative side S-phase rectifier diode 10Sb is connected in the forward direction from the negative output line β to the S-phase input terminal QS.

  The positive side T-phase rectifier diode 10Ta and the negative side T-phase rectifier diode 10Tb of the rectifier circuit 10 rectify the T-phase AC voltage input from the three-phase AC power supply 3 through the T-phase input terminal QT. Specifically, the positive side T-phase rectifying diode 10Ta is forwardly connected from the T-phase input terminal QT to the first positive output line α1. Further, the negative electrode side T-phase rectifying diode 10Tb is connected in the forward direction from the negative electrode output line β to the T-phase input terminal QT.

(Boost circuit)
The booster circuit 11 will be described in detail.
The booster circuit 11 can output a voltage twice as high as the maximum value of the three-phase AC voltages input from the three-phase AC power supply 3 as the DC voltage Vdc which is the output voltage of the three-phase voltage doubler rectifier circuit 1A. .
Here, in the following description, the DC voltage Vdc corresponding to the amplitude of the three-phase AC voltage is described as “single-voltage DC voltage Vdc1”, and the DC voltage Vdc corresponding to twice the amplitude of the three-phase AC voltage Described as “double voltage DC voltage Vdc2” to distinguish (Vdc1 = 1⁄2 · Vdc2). For example, when the three-phase AC power supply 3 outputs an AC voltage of 200 V AC, the single-voltage DC voltage Vdc1 is 200√2 V, and the double DC voltage Vdc2 is 400√2 V. Further, a voltage intermediate between the first-doubled DC voltage Vdc1 and the second-doubled DC voltage Vdc2 will be referred to as "intermediate voltage Vdc3". It is Vdc1 <Vdc3 <Vdc2.
The single-voltage DC voltage Vdc1 corresponds to an example of a reference voltage which is a voltage before being boosted.

  The booster circuit 11 includes a positive side main diode Da, a negative side main diode Db, a positive side switching element 11a, a negative side switching element 11b, and two capacitors (a positive side capacitor Ca and a negative side capacitor Cb). Prepare.

The two capacitors (positive electrode side capacitor Ca and negative electrode side capacitor Cb) are connected in series between the output and the output side of the booster circuit 11.
Specifically, the positive electrode side capacitor Ca is connected between the cathode of the positive electrode side main diode Da and the connection point N. The negative electrode side capacitor Cb is connected between the anode of the negative electrode side main diode Db and the connection point N.
The positive electrode side capacitor Ca and the negative electrode side capacitor Cb have the same capacitance value. Therefore, the connection point N is an intermediate potential point of the potential difference between the positive electrode output line α and the negative electrode output line β.

The positive main diode Da is connected in the forward direction from the positive output line α of the rectifier circuit 10 to the positive capacitor Ca. Specifically, the anode of the positive electrode side main diode Da is connected to the second positive electrode output line α2, and the cathode of the positive electrode side main diode Da is connected to the positive electrode side capacitor Ca.
The negative main electrode Db is connected in the forward direction from the negative capacitor Cb to the negative output line β of the rectifier circuit 10. Specifically, the anode of the negative electrode side main diode Db is connected to the negative electrode side capacitor Cb, and the cathode of the negative electrode side main diode Db is connected to the negative electrode output line β.

The positive electrode side switching element 11a and the negative electrode side switching element 11b are each a power transistor.
The positive electrode side switching element 11a is connected between the positive electrode output line α (the second positive electrode output line α2) and the connection point N. The negative electrode side switching element 11 b is connected between the negative electrode output line β and the connection point N.
The positive side switching element 11 a and the negative side switching element 11 b are on / off controlled by a switching control signal output from a boosting circuit control unit 12 described later.

In the case of this embodiment, the positive electrode side switching element 11a and the negative electrode side switching element 11b are IGBTs, respectively.
In this case, the collector of the positive electrode side switching element 11a is connected to the second positive electrode output line α2, and the emitter of the positive electrode side switching element 11a is connected to the connection point N. Furthermore, the emitter of the negative electrode side switching element 11b is connected to the negative electrode output line β, and the collector of the negative electrode side switching element 11b is connected to the connection point N.
The switching control signal is applied to the gate of the positive electrode side switching element 11a from the booster circuit control unit 12 described later, whereby the positive electrode side switching element 11a is on / off controlled.
Similarly, the switching control signal is applied from the booster circuit control unit 12 to the gate of the negative electrode side switching element 11b, whereby the negative electrode side switching element 11b is on / off controlled.

(Boost circuit controller)
The booster circuit control unit 12 will be described in detail.
FIG. 2 is a schematic block diagram showing a functional configuration of the booster circuit control unit 12.
As shown in FIG. 2, the booster circuit control unit 12 includes a mode determination unit 12 d and a switching element control unit 12 g.
The mode determination unit 12d determines the control mode of the booster circuit 11 to be any one of a voltage doubling mode, an intermediate voltage mode, and a voltage doubling mode.
The switching element control unit 12 g controls on / off of the positive electrode side switching element 11 a and the negative electrode side switching element 11 b according to the mode determined by the mode determination unit 12 d.

Next, operation of the inverter device 1 will be described with reference to FIGS.
FIG. 3 is a diagram showing an example of on / off of the positive electrode side switching element 11a and the negative electrode side switching element 11b in the single pressure mode. The horizontal axis in FIG. 3 indicates time.
In the single voltage doubling mode, the switching element control unit 12 g keeps both the positive electrode side switching element 11 a and the negative electrode side switching element 11 b in the OFF state.
When the rotational speed of the motor 4 detected by the rotational speed detection unit 13 becomes larger than a predetermined threshold value in the single pressure boosting mode, the mode determination unit 12 d switches the control mode of the booster circuit 11 to the intermediate voltage mode.

FIG. 4 is a diagram showing an example of on / off of the positive electrode side switching element 11a and the negative electrode side switching element 11b in the intermediate voltage mode. The horizontal axis in FIG. 4 indicates time.
In the intermediate voltage mode, the switching element control unit 12g repeats switching on / off of the positive electrode side switching element 11a and keeps the negative electrode side switching element 11b in the off state. Alternatively, the switching element control section 12 g may keep the positive electrode side switching element 11 a in the off state, and repeat switching of the negative electrode side switching element 11 b on / off.
When a predetermined time elapses after switching from the first voltage boosting mode to the intermediate voltage mode, the switching element control unit 12 g switches from the intermediate voltage mode to the double voltage mode.

FIG. 5 is a diagram showing an example of on / off of the positive electrode side switching element 11a and the negative electrode side switching element 11b in the double pressure mode. The horizontal axis in FIG. 5 indicates time.
In the double pressure mode, the switching element control unit 12g alternately switches on / off so that one of the positive side switching element 11a and the negative side switching element 11b is turned on and the other is turned off. The switching element control unit 12 g repeats this on / off switching.

  When the rotational speed of the motor 4 detected by the rotational speed detection unit 13 becomes equal to or less than a predetermined threshold in the double pressure mode, the mode determination unit 12 d switches the control mode of the booster circuit 11 to the intermediate voltage mode. When a predetermined time elapses after switching from the double voltage mode to the intermediate voltage mode, the switching element control unit 12g switches from the intermediate voltage mode to the single voltage mode.

  The inverter circuit control unit 21 switches control on the inverter circuit 20 in accordance with switching between the first voltage doubling mode, the intermediate voltage mode, and the second voltage doubling mode. For example, the inverter circuit control unit 21 switches the calculation reference of the pulse width in PWM control. In the double pressure mode, using the standard that is calculated to be half the pulse width in the case of the double pressure mode, in the intermediate voltage mode, it is calculated to be an intermediate pulse width between the case of the single pressure mode and the case of the double pressure mode. Use the standard.

Thus, by switching the pulse width in PWM control according to the mode, the inverter circuit control unit 21 can switch the mode so that the pulse width becomes relatively wide, In this respect, the efficiency of the power supply to the motor 4 can be made relatively high.
Further, the inverter circuit control unit 21 can perform control of the inverter circuit 20 corresponding to the switching of the mode by a relatively simple process of switching the pulse width in PWM control in three steps.

FIG. 6 is a diagram showing an example of the value of the DC voltage Vdc when switching from the voltage doubling mode to the intermediate voltage mode and the voltage doubling mode. The horizontal axis of the graph of FIG. 6 indicates time, and the vertical axis indicates DC voltage Vdc. In the example of FIG. 6, the mode determination unit 12 d switches the control mode of the booster circuit 11 in the order of the first voltage doubling mode, the intermediate voltage mode, and the second voltage doubling mode.
As described above, when the number of rotations of the motor 4 detected by the number-of-rotations detection unit 13 becomes larger than a predetermined threshold in the first voltage boosting mode, the mode determination unit 12d switches the control mode of the booster circuit 11 to the intermediate voltage mode. . When a predetermined time elapses after switching from the first voltage boosting mode to the intermediate voltage mode, the switching element control unit 12 g switches from the intermediate voltage mode to the double voltage mode.

In the single voltage boosting mode, both the positive electrode side switching element 11a and the negative electrode side switching element 11b are turned off, and the DC voltage Vdc becomes the single voltage DC voltage Vdc1 corresponding to the amplitude of the three-phase AC voltage.
In the intermediate voltage mode, the switching element control unit 12g switches on / off of the positive electrode side switching element 11a. When the positive electrode side switching element 11a is turned on, a circuit connecting the both ends of the rectifier circuit 10 and the both ends of the negative electrode side capacitor Cb is formed, and the voltage of the negative electrode side capacitor Cb corresponds to the single-boost DC voltage Vdc1. Thus, the negative electrode side capacitor Cb is charged. As a result, the DC voltage Vdc becomes an intermediate voltage Vdc3 higher than the single-voltage DC voltage Vdc1.

In the double pressure mode, the switching element control unit 12g alternately switches on / off so that one of the positive side switching element 11a and the negative side switching element 11b is turned on and the other is turned off.
When the positive electrode side switching element 11a is turned on, a circuit connecting the both ends of the rectifier circuit 10 and the both ends of the negative electrode side capacitor Cb is formed, and the voltage of the negative electrode side capacitor Cb corresponds to the single-boost DC voltage Vdc1. Thus, the negative electrode side capacitor Cb is charged. Further, when the negative electrode side switching element 11b is turned on, a circuit connecting both ends of the rectifier circuit 10 and the both ends of the positive electrode side capacitor Ca is formed, and the voltage of the positive electrode side capacitor Ca corresponds to the single-voltage DC voltage Vdc1. The positive electrode side capacitor Ca is charged so as to obtain the above voltage.
As a result, the DC voltage Vdc becomes higher than the intermediate voltage Vdc3 and becomes a double DC voltage Vdc2 which is twice as high as the single-voltage DC voltage Vdc1.

  Compared with the case of switching from the double voltage DC voltage Vdc1 directly to the double voltage DC voltage Vdc2 by switching the double voltage DC voltage Vdc2 after switching the DC voltage Vdc from the single voltage DC voltage Vdc1 to the intermediate voltage Vdc3. Thus, sudden changes in the voltage supplied to the motor 4 can be suppressed. This can reduce the possibility of the motor 4 being out of step.

FIG. 7 is a diagram showing an example of the value of the DC voltage Vdc when switching from the double voltage mode to the intermediate voltage mode and the single voltage mode. The horizontal axis of the graph of FIG. 7 indicates time, and the vertical axis indicates DC voltage Vdc. In the example of FIG. 7, the mode determination unit 12 d switches the control mode of the booster circuit 11 in the order of the double voltage mode, the intermediate voltage mode, and the single voltage mode.
As described above, when the rotational speed of the motor 4 detected by the rotational speed detection unit 13 becomes equal to or less than the predetermined threshold in the double pressure mode, the mode determination unit 12 d switches the control mode of the booster circuit 11 to the intermediate voltage mode. . When a predetermined time elapses after switching from the double voltage mode to the intermediate voltage mode, the switching element control unit 12g switches from the intermediate voltage mode to the single voltage mode.
Compared with the case where the double voltage DC voltage Vdc2 is switched directly to the single voltage DC voltage Vdc1 by switching the DC voltage Vdc from the double voltage DC voltage Vdc2 to the intermediate voltage Vdc3 and then switching to the single voltage DC voltage Vdc1. Thus, sudden changes in the voltage supplied to the motor 4 can be suppressed. This can reduce the possibility of the motor 4 being out of step.

As described above, with respect to the inverter circuit 20 for supplying electric power to the motor 4, the booster circuit 11 has the single-voltage DC voltage Vdc1 and the double-voltage DC voltage Vdc2 equivalent to twice the single-voltage DC voltage Vdc1. An intermediate voltage Vdc3 which is an intermediate voltage between the first-doubled DC voltage Vdc1 and the second-doubled DC voltage Vdc2 is supplied. The booster circuit control unit 12 supplies the intermediate voltage Vdc3 from the state where the booster circuit 11 supplies the first boosted DC voltage Vdc1 to the inverter circuit 20, and then supplies the doubled DC voltage Vdc2. Control.
Compared with the case of switching from the double voltage DC voltage Vdc1 directly to the double voltage DC voltage Vdc2 by switching to the double voltage DC voltage Vdc2 after switching the DC voltage Vdc from the single voltage DC voltage Vdc1 to the intermediate voltage Vdc3. Thus, sudden changes in the voltage supplied to the motor 4 can be suppressed. This can reduce the possibility of the motor 4 being out of step. In particular, regardless of the presence or absence of field weakening control, the possibility that the motor 4 is out of step can be reduced.

Further, after the booster circuit 11 supplies the intermediate voltage Vdc3 from the state where the booster circuit 11 supplies the doubled DC voltage Vdc2 to the inverter circuit 20, the booster circuit control unit 12 boosts the voltage to supply the single-voltage DC voltage Vdc1. The circuit 11 is controlled.
Compared with the case where the double voltage DC voltage Vdc2 is switched directly to the single voltage DC voltage Vdc1 by switching the DC voltage Vdc from the double voltage DC voltage Vdc2 to the intermediate voltage Vdc3 and then switching to the single voltage DC voltage Vdc1. Thus, sudden changes in the voltage supplied to the motor 4 can be suppressed. This can reduce the possibility of the motor 4 being out of step. In particular, regardless of the presence or absence of field weakening control, the possibility that the motor 4 is out of step can be reduced.

  Further, the positive side capacitor Ca and the negative side capacitor Cb are connected in series to the inverter circuit 20. The positive electrode side switching element 11a forms a circuit which connects both ends of the rectifier circuit 10 which is a voltage supply source and both ends of the negative electrode side capacitor Cb by being turned on by itself. The negative electrode side switching element 11b forms a circuit which connects the both ends of the rectifier circuit 10 and the both ends of the positive electrode side capacitor Ca when the negative electrode side switching element 11b is turned on. The booster circuit control unit 12 repeats switching on / off of any one of the positive electrode side switching device 11 a and the negative electrode side switching device 11 b, and turns off the other switching device, whereby the booster circuit 11 is realized. Controls to supply the intermediate voltage. Further, the booster circuit control unit 12 turns on / off these switching elements so that one of the switches of the positive side switching element 11a and the negative side switching element 11b is turned on and the other switching element is turned off. By repeating the switching, the booster circuit 11 is controlled to supply the doubled DC voltage.

Thus, the booster circuit 11 uses the elements for supplying the doubled DC voltage (in particular, using the positive side switching element 11a, the negative side switching element 11b, the positive side capacitor Ca, and the negative side capacitor Cb) as an intermediate It can supply voltage. The booster circuit 11 does not need to further include an element for supplying the intermediate voltage, and in this respect, the complication of the booster circuit 11 can be avoided.
Further, the booster circuit control unit 12 is relatively simple in that switching on / off of any one of the positive side switching element 11a and the negative side switching element 11b is repeated, and the other switching element is turned off. The step-up circuit 11 can be controlled to supply the intermediate voltage by such control.

Note that a program for realizing all or part of functions of the booster circuit control unit 12 is recorded in a computer readable recording medium, and the computer system reads the program recorded in the recording medium and executes it. The processing of each part may be performed by Here, the “computer system” includes an OS and hardware such as peripheral devices.
The "computer system" also includes a homepage providing environment (or display environment) if the WWW system is used.
The term "computer-readable recording medium" refers to a storage medium such as a flexible disk, a magneto-optical disk, a ROM, a portable medium such as a ROM or a CD-ROM, or a hard disk built in a computer system. The program may be for realizing a part of the functions described above, or may be realized in combination with the program already recorded in the computer system.

  Although the embodiments of the present invention have been described in detail with reference to the drawings, the specific configuration is not limited to this embodiment, and design changes and the like within the scope of the present invention are also included.

DESCRIPTION OF SYMBOLS 1 inverter apparatus 1A three phase voltage doubler rectifier circuit 4 motor 10 rectifier circuit 11 step-up circuit 11a positive electrode side switching element 11b negative electrode side switching element Ca positive electrode side capacitor Cb negative electrode side capacitor 12 step-up circuit control part 12d mode determination part 12g switching element control part 13 Rotational Speed Detection Unit 20 Inverter Circuit 21 Inverter Circuit Control Unit

Claims (5)

For an inverter circuit for supplying electric power to a motor, a single boosting DC voltage, a double boosting DC voltage corresponding to twice the single boosting DC voltage, the single boosting DC voltage and a double boosting DC voltage A booster circuit for supplying any DC voltage out of an intermediate voltage which is an intermediate voltage of
A booster circuit control unit that controls the booster circuit to supply the intermediate voltage after supplying the intermediate voltage from the state where the booster circuit supplies the single-voltage DC voltage to the inverter circuit. When,
An inverter device comprising: The booster circuit control unit is configured to supply the intermediate voltage from the state where the booster circuit supplies the doubled DC voltage to the inverter circuit, and then supply the one-fold DC voltage. Control the
The inverter device according to claim 1. The booster circuit is
A positive side capacitor and a negative side capacitor connected in series with the inverter circuit;
A positive electrode side switching element forming a circuit which connects both ends of a rectifier circuit which is a voltage supply source and both ends of the negative electrode side capacitor by being turned on by itself;
A negative electrode side switching element forming a circuit which connects both ends of the rectifier circuit and both ends of the positive electrode side capacitor by turning on itself.
Equipped with
The step-up circuit control unit repeats switching on / off of any one of the positive-side switching element and the negative-side switching element, and turns off the other switching element, whereby the step-up circuit Control is performed to supply the intermediate voltage, and one of the positive and negative switching elements is turned on and the other switching element is turned off. Controlling the booster circuit to supply the doubled DC voltage by repeating the switching of
The inverter apparatus of Claim 1 or Claim 2. For an inverter circuit for supplying electric power to a motor, a single boosting DC voltage, a double boosting DC voltage corresponding to twice the single boosting DC voltage, the single boosting DC voltage and a double boosting DC voltage The booster circuit for supplying any one of the DC voltages among the intermediate voltages which are intermediate voltages of the voltage supply circuit supplies the intermediate voltage from the state where the single-voltage DC voltage is supplied to the inverter circuit. A control method of a booster circuit, comprising: controlling the booster circuit to supply a pressure DC voltage. For an inverter circuit for supplying electric power to a motor, a single boosting DC voltage, a double boosting DC voltage corresponding to twice the single boosting DC voltage, the single boosting DC voltage and a double boosting DC voltage A computer for controlling a booster circuit that supplies any DC voltage out of an intermediate voltage which is an intermediate voltage of
A program for controlling the step-up circuit to supply the intermediate voltage after supplying the intermediate voltage from the state where the single-voltage DC voltage is supplied to the inverter circuit.

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