Control device, motor drive device, control method and program

Abstract

To provide a control device capable of suppressing torque fluctuations, rotation speed fluctuations, and operating range reduction in a high-speed range of a motor even when a fluctuating voltage is input to an inverter.SOLUTION: A control device for a permanent magnet synchronous motor which includes means that sets a voltage command on two axes of a rotating orthogonal coordinate system, means that coordinate transforms a voltage command of two axes to three phases, means that applies a three-phase voltage command to a motor through power conversion by an inverter, means that feeds back a terminal current of the motor, means that determines a power factor angle from the feedback current, and means that adjusts the power factor angle to the phase used when the terminal current of the motor obtained in three phases is converted into rectangular coordinates, includes a holding unit that holds a relationship between the fluctuation of the DC voltage supplied to the inverter and a phase correction value, and complementary means that adds a correction value to at least one of the phase used when performing three-phase / two-phase conversion to convert three-phase into two-phase and the phase used when performing two-phase / three-phase conversion to convert two-phase into three-phase.SELECTED DRAWING: Figure 2

Description

[Technical field]

[0001] The present disclosure relates to a control device, a motor drive device, a control method, and a program. [Background technology]

[0002] In some cases, the DC voltage generated by the converter is supplied to an inverter, which is then controlled to drive a motor. In general, the voltage output from the converter is smoothed by a large-capacity capacitor. [Prior art documents] [Patent documents]

[0003] [Patent Document 1] Patent No. 4764124 Summary of the Invention [Problem to be solved by the invention]

[0004] Incidentally, if the capacitance of the capacitor for smoothing the converter output voltage is small, the device for driving the motor can be made smaller. However, if the capacitance of the capacitor is small, the output voltage of the converter is more likely to fluctuate than when the capacitance of the capacitor is larger. As a result, in the high-speed range where the motor voltage required to drive the motor is equal to or greater than the DC voltage, the motor voltage is affected by the fluctuation of the DC voltage, and the motor speed and torque fluctuations increase, which may make it impossible to drive the motor stably. In addition, the fluctuation of the motor current also increases, which may narrow the operating range.

[0005] Therefore, there is a demand for technology that can suppress torque fluctuations, rotational speed fluctuations, and narrowing of the operating range in the high speed range of the motor even when a fluctuating voltage is input to the inverter.

[0006] The present disclosure has been made to solve the above-mentioned problems, and aims to provide a control device, a motor drive device, a control method, and a program that can suppress torque fluctuations, rotation speed fluctuations, and narrowing of the operating range of a motor in the high-speed range even when a fluctuating voltage is input to an inverter. [Means for solving the problem]

[0007] In order to solve the above problems, the control device according to the present disclosure includes: a control device for a permanent magnet synchronous motor having a means for setting a voltage command on two axes of a rotating orthogonal coordinate system, a means for converting the voltage commands of the two axes into three phases, a means for applying the voltage commands of the three phases to a motor via power conversion by an inverter, a means for feeding back a terminal current of the motor, a power factor angle determining means for determining a power factor angle from the terminal current fed back, and a power factor angle adjusting means for adjusting the power factor angle to a phase used when converting the terminal current of the motor obtained in the three phases into an orthogonal coordinate system, the control device comprising: a holding unit for holding a relationship between a periodic fluctuation of a DC voltage supplied to the inverter by a capacitor connected to an input of the inverter and a correction value of a phase; and a correction value adding means for adding the correction value to at least one of a phase used when performing a 3-phase to 2-phase conversion for converting the three phases into two phases corresponding to the two axes and a phase used when performing a 2-phase to 3-phase conversion for converting the two phases into the three phases. .

[0008] A motor drive device according to the present disclosure includes the above control device and the inverter.

[0009] The control method according to the present disclosure includes: A control method for a permanent magnet synchronous motor using a control device having: means for setting voltage commands on two axes of a rotating orthogonal coordinate system; means for converting the voltage commands of the two axes into three phases; means for applying the three-phase voltage commands to a motor via power conversion by an inverter; means for feeding back a terminal current of the motor; power factor angle determining means for determining a power factor angle from the terminal current fed back; and power factor angle adjusting means for adjusting the power factor angle to a phase used when converting the terminal current of the motor obtained in the three phases into an orthogonal coordinate system, the control method including: maintaining a relationship between a periodic fluctuation of a DC voltage supplied to the inverter by a capacitor connected to an input of the inverter and a phase correction value; and adding the correction value to at least one of a phase used when performing a three-phase to two-phase conversion for converting the three phases into two phases corresponding to the two axes and a phase used when performing a two-phase to three-phase conversion for converting the two phases into the three phases. .

[0010] The program according to the present disclosure is a computer for a control device for a permanent magnet synchronous motor, the computer comprising: means for setting voltage commands on two axes of a rotating orthogonal coordinate system; means for converting the two-axis voltage commands into three phases; means for applying the three-phase voltage commands to a motor via power conversion by an inverter; means for feeding back a terminal current of the motor; a power factor angle determining means for determining a power factor angle from the terminal current that is fed back; and a power factor angle adjusting means for adjusting the power factor angle to a phase used when converting the terminal current of the motor obtained in the three phases into an orthogonal coordinate system, maintaining a relationship between a periodic fluctuation of a DC voltage supplied to the inverter by a capacitor connected to an input of the inverter and a phase correction value; and adding the correction value to at least one of a phase used when performing a three-phase to two-phase conversion for converting the three phases into two phases corresponding to the two axes and a phase used when performing a two-phase to three-phase conversion for converting the two phases into the three phases. . The control device according to the present disclosure is a control device for a permanent magnet synchronous motor having a means for setting voltage commands on two axes of a rotating orthogonal coordinate system, a means for coordinate transforming the two-axis voltage commands to three phases, a means for applying the three-phase voltage commands to a motor via power conversion by an inverter, and a means for feeding back a terminal current of the motor, and is equipped with a holding unit that holds a relationship between a phase correction value and a periodic fluctuation of a DC voltage supplied to the inverter by a capacitor connected to the input of the inverter, and a correction value adding means that adds the correction value to at least one of the phases used when performing a 3-phase to 2-phase conversion that converts the three phases into two phases corresponding to the two axes and the phases used when performing a 2-phase to 3-phase conversion that converts the two phases into the three phases. Effect of the Invention

[0011] According to the control device, motor drive device, control method, and program of the present disclosure, torque fluctuations, rotation speed fluctuations, and narrowing of the operating range of the motor in the high speed range can be suppressed even if a fluctuating voltage is input to the inverter. [Brief description of the drawings]

[0012] [Figure 1] 1 is a diagram illustrating an example of a configuration of a motor drive device according to an embodiment of the present disclosure. [Diagram 2] FIG. 2 is a diagram illustrating an example of a configuration of a control device according to an embodiment of the present disclosure. [Diagram 3] FIG. 4 illustrates an example of a first phase correction function according to an embodiment of the present disclosure. [Figure 4] FIG. 13 illustrates an example of a second phase correction function according to an embodiment of the present disclosure. [Diagram 5]FIG. 1 is a first diagram illustrating an example of a processing flow of a control device according to an embodiment of the present disclosure. [Figure 6] FIG. 2 is a second diagram illustrating an example of a processing flow of the control device according to an embodiment of the present disclosure. [Figure 7] FIG. 1 is a schematic block diagram illustrating a configuration of a computer according to at least one embodiment. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0013] <Embodiment> Hereinafter, the embodiments will be described in detail with reference to the drawings. A motor drive device according to an embodiment of the present disclosure will be described. (Configuration of the motor drive device) Fig. 1 is a diagram showing a configuration of a motor drive device 1 according to an embodiment of the present disclosure. As shown in Fig. 1, the motor drive device 1 includes a power supply 10, a converter 20, a reactor 30, a first capacitor 40, a second capacitor 50, an inverter 60, a motor 70, a current sensor 80, and a control device 90. The motor drive device 1 is a device that can suppress pulsations in the torque and rotation speed of the motor 70 by controlling the inverter 60 in accordance with the voltage fluctuations, even when there are large voltage fluctuations in the output voltage of the converter 20 in the high-speed range of the motor 70, and can also suppress a reduction in the operating range by suppressing pulsations in the motor current.

[0014] The power supply 10 is a power supply that outputs a three-phase AC voltage. The three-phase AC voltage output by the power supply 10 is input to the converter 20. The converter 20 converts a three-phase AC voltage into a DC voltage. The converter 20 is, for example, a diode rectifier circuit. However, the converter 20 is not limited to a diode rectifier circuit, and may be another rectifier circuit using a switching element or the like.

[0015] The reactor 30 and the first capacitor 40 constitute an LC filter. This LC filter removes voltage fluctuations of a frequency component determined by a resonance frequency due to the inductance of the reactor 30 and the capacitance of the first capacitor 40, among the voltage fluctuations in the voltage output by the converter 20. The first capacitor 40 is, for example, a film capacitor. Film capacitors generally have a smaller capacity than electrolytic capacitors, but are small, lightweight, and have a long life. When the first capacitor 40 is a small-capacity film capacitor, the voltage fluctuations at the input of the inverter 60 become larger than when the first capacitor 40 is a large, large-capacity electrolytic capacitor.

[0016] The second capacitor 50 is a snubber capacitor that suppresses voltage fluctuations caused by switching noise that occurs when the inverter 60 converts a DC voltage into an AC voltage using a switching element.

[0017] Under the control of the control device 90, the inverter 60 generates an AC voltage for driving the motor 70 from the DC voltage supplied from the converter 20 via the above-mentioned LC filter. The inverter 60 includes switching elements SW1, SW2, SW3, SW4, SW5, and SW6. The switching elements SW1 to SW6 are semiconductor elements having control terminals (gate terminals in the case of IGBTs and MOSFETs), such as IGBTs (Insulated Gate Bipolar Transistors) and MOSFETs (Metal-Oxide-Semiconductor Field Effect Transistors).

[0018] The motor 70 rotates in response to the AC voltage supplied to the inverter 60. The motor 70 is, for example, a compressor motor used in an air conditioner. The current sensor 80 detects motor currents iu, iv, and iw. iu is a motor current corresponding to the u-phase of the inverter 60. iv is a motor current corresponding to the v-phase of the inverter 60. iw is a motor current corresponding to the w-phase of the inverter 60.

[0019] (Control device configuration) The control device 90 generates a control signal for controlling the inverter 60. As shown in Fig. 2, the control device 90 includes a voltage detection circuit 110a, a current detection circuit 110b, a voltage command generation unit 110c, and a PWM (Pulse Width Modulation) duty calculation unit 110d (an example of a calculation unit). An example of a specific method of motor control by the control device 90 includes V / F (Variable Frequency) control.

[0020] The voltage detection circuit 110a identifies the voltage Vx between both terminals of the first capacitor 40. For example, the voltage detection circuit 110a includes an A / D (Analog to Digital) converter 110a1. The A / D converter 110a1 receives the voltage Vx between both terminals of the first capacitor 40. The A / D converter 110a1 converts the received voltage Vx into a digital value that corresponds one-to-one to the received voltage Vx (i.e., a digital value that indicates the value of the received voltage).

[0021] The current detection circuit 110b identifies the values ​​of the motor currents iu, iv, and iw detected by the current sensor 80.

[0022] (Configuration of voltage command generation unit) In FIG. 2, ω_cmd is a speed command (electrical angle). ω is the output frequency of the inverter 60. vd is a d-axis voltage command. vq is a q-axis voltage command. vu is a u-phase voltage command. vv is a v-phase voltage command. vw is a w-phase voltage command. id is the d-axis inverter output current. iq is the q-axis inverter output current. Vx is the voltage between both terminals of the first capacitor 40 detected by the voltage detection circuit 110a. θc1 is a phase correction amount when generating voltage commands vu, vv, and vw from the d-axis voltage command vd and the q-axis voltage command vq.

[0023] As shown in FIG. 2, the voltage command generating unit 110c has a first functional unit f1, a second functional unit f2, a third functional unit f3, a fourth functional unit f4, a fifth functional unit f5, a sixth functional unit f6, a seventh functional unit f7, an eighth functional unit f8, a ninth functional unit f9, and a tenth functional unit f10.

[0024] The first functional unit f1 receives the inverter output current iq from the tenth functional unit f10. The first functional unit f1 has a proportional constant k ω The inverter output current iq is a current that contributes to the generation of torque by the motor 70. (Proportionality constant k ω and the inverter output current iq multiplied by k ω Iq is as described in Patent Document 1, and is used to prevent loss of synchronization by feeding back torque fluctuations to the rotation speed.

[0025] The second functional unit f2 receives the output of the first functional unit f1. The second functional unit f2 also receives a speed command ω_cmd. The second functional unit f2 subtracts the output of the first functional unit f1 from the speed command ω_cmd. The second functional unit f2 outputs the subtraction result as the output frequency ω of the inverter 60 to the third functional unit f3, the fourth functional unit f4, and the eighth functional unit f8.

[0026] The third functional unit f3 receives the output frequency ω of the inverter 60 from the second functional unit f2. The third functional unit f3 also receives the inverter output current id from the tenth functional unit f10. The third functional unit f3 generates a d-axis voltage command vd by substituting the inverter output current id into the following equation (1). The third functional unit f3 outputs the generated d-axis voltage command vd to the fifth functional unit f5.

[0027]

number

[0028] Here, Kpd is a proportionality constant. Moreover, the third functional unit f3 generates a q-axis voltage command vq by substituting the output frequency ω of the inverter 60 into the following equation (2). The third functional unit f3 outputs the generated q-axis voltage command vq to the fifth functional unit f5.

[0029]

number

[0030] Here, λd is an induced voltage coefficient, and Vqofs is a q-axis voltage offset value. The q-axis voltage offset value Vqofs can be expressed as the following equation (3) using a proportionality constant K.

[0031]

number

[0032] According to the above formulas (1) and (2), the inverter output current id is controlled to be zero. When the inverter output current id on the d axis becomes zero, the inverter output voltage on the d axis also becomes zero.

[0033] The fourth functional unit f4 receives the output frequency ω of the inverter 60 from the second functional unit f2. The fourth functional unit d4 integrates the output frequency ω of the inverter 60 in the time axis direction. The fourth functional unit f4 outputs the integration result to the sixth functional unit f6 and the seventh functional unit f7.

[0034] The eighth functional unit f8 receives a digital value indicating the voltage Vx between both terminals of the first capacitor 40 from the voltage detection circuit 110a. The eighth functional unit f8 also receives the output frequency ω of the inverter 60 from the second functional unit f2. The eighth functional unit f8 determines a correction value θc1 based on the received digital value, the received output frequency ω, and a first phase correction function Fn1 (an example of a relationship between a fluctuation in a DC voltage supplied to the inverter and a correction value for the phase). The eighth functional unit f8 also determines a correction value θc2 based on the received digital value, the received output frequency ω, and a second phase correction function Fn2 (an example of a relationship between a fluctuation in a DC voltage supplied to the inverter and a correction value for the phase). The correction value θc1 is a correction value for correcting a phase used when the fifth functional unit f5 performs a two-phase to three-phase conversion. The correction value θc2 is a correction value for correcting a phase used when the tenth functional unit f10 performs a three-phase to two-phase conversion. These correction values ​​θc1 and θc2 are used to control the magnitude of the phase to change in accordance with the amount of change in the voltage Vx between both terminals of the first capacitor 40. FIG. 3 is a diagram showing an example of a first phase correction function Fn1 according to an embodiment. FIG. 4 is a diagram showing an example of a second phase correction function Fn2 according to an embodiment. The first phase correction function Fn1 is a function determined in advance by performing simulations and experiments, and is a function capable of specifying the correction value θc1 based on the DC voltage between both terminals of the first capacitor 40 and the voltage required to drive the motor 70. The second phase correction function Fn2 is a function determined in advance by performing simulations and experiments, and is a function capable of specifying the correction value θc2 based on the DC voltage between both terminals of the first capacitor 40 and the voltage required to drive the motor 70. The correction value θc1 is added to the phase at which the seventh function unit f7 performs the 2-phase to 3-phase conversion. The correction value θc2 is added to the phase at which the sixth function unit f6 performs the 3-phase to 2-phase conversion.

[0035] Specifically, the first phase correction function Fn1 is a function of the voltage Vx across the first capacitor and the voltage required for the motor 70, and is a function for determining a correction value. The voltage required for the motor 70 is obtained by multiplying the output frequency ω of the inverter 60 by the induced voltage coefficient λd. That is, the first phase correction function Fn1 is a function of the voltage Vx across the first capacitor and the output frequency ω of the inverter 60, and includes the induced voltage coefficient λd. Then, the voltage Vx across the first capacitor and the output frequency ω of the inverter 60 are substituted into the first phase correction function Fn1 to specify each correction value θc1. That is, the eighth functional unit f8 specifies the value of the first phase correction function Fn1 (i.e., the correction value θc1) by substituting the voltage Vx and the output frequency ω into the first phase correction function Fn1. The correction value θc1 specified by the eighth functional unit f8 in this manner becomes the correction value used in the seventh functional unit f7.

[0036] Specifically, the second phase correction function Fn2 is a function of the voltage Vx across the first capacitor and the voltage required for the motor 70, and is a function for determining a correction value. The voltage required for the motor 70 is obtained by multiplying the output frequency ω of the inverter 60 by the induced voltage coefficient λd. That is, the second phase correction function Fn2 is a function of the voltage Vx across the first capacitor and the output frequency ω of the inverter 60, and includes the induced voltage coefficient λd. Then, the voltage Vx across the first capacitor and the output frequency ω of the inverter 60 are substituted into the second phase correction function Fn2 to specify each correction value θc2. That is, the eighth functional unit f8 specifies the value of the second phase correction function Fn2 (i.e., the correction value θc2) by substituting the voltage Vx and the output frequency ω into the second phase correction function Fn2. The correction value θc2 specified by the eighth functional unit f8 in this manner becomes the correction value used in the sixth functional unit f6.

[0037] In addition, when calculating the voltage required for the motor 70 in more detail, the eighth functional unit f8 may add, for example, the product of the output frequency ω multiplied by the induced voltage coefficient λd, the product of the imaginary number j, the output frequency ω, the inductance of the q-axis, and the current of the q-axis. That is, the eighth functional unit f8 may calculate the voltage required for the motor 70 by performing a vector calculation expressed by a complex number (for example, by using the phasor method). In this case, the eighth functional unit f8 may store the inductance of the q-axis in advance, and may obtain and use the inverter output current iq output by the tenth functional unit f10 as the current of the q-axis. As a result, the first phase correction function Fn1 and the second phase correction function Fn2 may be the same function or different functions.

[0038] The correction value θc1 and the correction value θc2 are not limited to being specified using functions such as the above-mentioned first phase correction function Fn1 and the second phase correction function Fn2. For example, the voltage Vx across the first capacitor and the voltage required for the motor 70 may be associated with the corresponding correction values ​​and stored as, for example, a data table (an example of the relationship between the fluctuation of the DC voltage supplied to the inverter and the phase correction value), and the eighth functional unit f8 may specify the voltage Vx across the first capacitor and the voltage required for the motor 70, and specify the correction value stored in the data table associated with the specified voltage Vx across the first capacitor and the voltage required for the motor 70 as the desired correction value.

[0039] The sixth functional unit f6 receives the integration result from the fourth functional unit f4. The sixth functional unit f6 also receives the correction value θc2 from the eighth functional unit f8. The sixth functional unit f6 adds the correction value θc2 to the integration result. In other words, the sixth functional unit f6 corrects the integration result of the output frequency ω of the inverter 60 using the correction value θc2. The sixth functional unit f6 outputs the addition result θes to the tenth functional unit f10.

[0040] The tenth functional unit f10 receives the sum θes from the sixth functional unit f6. The tenth functional unit f10 also receives the motor currents iu, iv, and iw of the u-phase, v-phase, and w-phase, respectively, from the current detection circuit 110b at a predetermined time interval. The tenth functional unit f10 converts the motor currents iu, iv, and iw into inverter output currents id and iq from three-phase to two-phase using, for example, the following equation (4) with the sum θes as the phase. The tenth functional unit f10 outputs the inverter output current id to the third functional unit f3. The tenth functional unit f10 also outputs the inverter output current iq to the first functional unit f1 and the ninth functional unit.

[0041]

number

[0042] The ninth functional unit f9 specifies the power factor angle φv using the inverter output current iq. This specification may be performed, for example, in the same manner as described in Patent Document 1. The ninth functional unit f9 outputs the specified power factor angle φv to the seventh functional unit f7.

[0043] The seventh functional unit f7 receives the integration result from the fourth functional unit f4. The seventh functional unit f7 also receives the correction value θc1 from the eighth functional unit f8. The seventh functional unit f7 also receives the power factor angle φv from the ninth functional unit f9. The seventh functional unit f7 adds the integration result, the correction value θc1, and the power factor angle φv. The seventh functional unit f7 outputs the addition result θv23 to the fifth functional unit f5.

[0044] The fifth functional unit f5 receives the d-axis voltage command vd and the q-axis voltage command vq from the third functional unit f3. The fifth functional unit f5 also receives the addition result θv23 from the seventh functional unit f7. The fifth functional unit f5 converts the d-axis voltage command vd and the q-axis voltage command vq into a u-phase voltage command vu, a v-phase voltage command vv, and a w-phase voltage command vw, for example, using the following equation (5).

[0045]

number

[0046] The PWM duty calculation unit 110d generates a PWM signal for controlling the inverter 60, the duty ratio of which is determined based on the DC voltage between both terminals of the first capacitor 40 and the voltage commands vu, vv, and vw. For example, in the high speed range of the motor 70, the PWM duty calculation unit 110d uses the phase θv23 corrected using the correction value θc1 to generate a PWM signal for controlling the inverter 60, the duty ratio of which is determined based on the u-phase voltage command vu, the v-phase voltage command vv, and the w-phase voltage command vw that are output by the fifth functional unit f5 after 2-phase to 3-phase conversion, and the DC voltage between both terminals of the first capacitor 40.

[0047] (Processing performed by the control device) Next, the processing of 2-phase to 3-phase conversion and 3-phase to 2-phase conversion performed when the control device 90 generates a PWM signal for controlling the inverter 60 in the high speed range of the motor 70 will be described with reference to Figures 5 and 6. First, the processing of 2-phase to 3-phase conversion performed by the control device 90 will be described.

[0048] The voltage detection circuit 110a determines the voltage Vx between both terminals of the first capacitor 40. The voltage detection circuit 110a outputs the determined voltage Vx to the eighth functional unit f8. The eighth functional unit f8 acquires the voltage Vx output by the voltage detection circuit 110a (step S1).

[0049] Furthermore, the second functional unit f2 outputs the output frequency ω of the inverter 60 to the eighth functional unit f8. The eighth functional unit f8 acquires the output frequency ω output by the second functional unit f2. The eighth functional unit f8 calculates the voltage required for the motor 70 based on the acquired output frequency ω (step S2). For example, the eighth functional unit f8 multiplies the output frequency ω by an induced voltage coefficient λd to calculate the voltage required for the motor 70.

[0050] The eighth functional unit f8 specifies the correction value θc1 from the first phase correction function Fn1. For example, the eighth functional unit f8 assigns the acquired voltage Vx and the calculated voltage required for the motor 70 to the first phase correction function Fn1 to specify the value of the first phase correction function Fn1, that is, the correction value θc1 (step S3). The eighth functional unit f8 outputs the specified correction value θc1 to the seventh functional unit f7.

[0051] The seventh functional unit f7 acquires the correction value θc1 output by the eighth functional unit f8. The seventh functional unit f7 also acquires the integration result output by the fourth functional unit f4. The seventh functional unit f7 also acquires the power factor angle φv output by the ninth functional unit f9. The seventh functional unit f7 adds the integration result, the power factor angle φv, and the correction value θc1 to calculate the addition result θv23. That is, the seventh functional unit f7 changes the phase used in the two-phase to three-phase conversion to θv23 by adding the correction value θc1 to the phase used in the two-phase to three-phase conversion (step S4). The seventh functional unit f7 outputs the phase θv23 to the fifth functional unit f5.

[0052] The fifth functional unit f5 acquires the phase θv23 output by the seventh functional unit f7. The fifth functional unit f5 acquires the phase θv23 output by the seventh functional unit f7. The fifth functional unit f5 also acquires the d-axis voltage command vd and the q-axis voltage command vq output by the third functional unit f3. The fifth functional unit f5 converts the voltage commands of two axes (i.e., the d-axis voltage command vd and the q-axis voltage command vq) into voltage commands of three axes (i.e., the voltage command vu, the voltage command vv, and the voltage command vw) using the phase θv23 (step S5). The fifth functional unit f5 outputs the voltage commands of the three axes to the PWM duty calculation unit 110d.

[0053] The PWM duty calculation unit 110d acquires the three-axis voltage command output by the fifth functional unit f5. The PWM duty calculation unit 110d also acquires the DC voltage Vx output by the voltage detection circuit 110a. The PWM duty calculation unit 110d generates a PWM signal for controlling the inverter 60 based on the three-axis voltage command output by the fifth functional unit f5 and the DC voltage Vx output by the voltage detection circuit 110a. The PWM duty calculation unit 110d then outputs the generated PWM signal to the inverter 60.

[0054] Next, the three-phase to two-phase conversion process performed by the control device 90 will be described. The voltage detection circuit 110a determines the voltage Vx between both terminals of the first capacitor 40. The voltage detection circuit 110a outputs the determined voltage Vx to the eighth functional unit f8. The eighth functional unit f8 acquires the voltage Vx output by the voltage detection circuit 110a (step S6).

[0055] Furthermore, the second functional unit f2 outputs the output frequency ω of the inverter 60 to the eighth functional unit f8. The eighth functional unit f8 acquires the output frequency ω output by the second functional unit f2. The eighth functional unit f8 calculates the voltage required for the motor 70 based on the acquired output frequency ω (step S7). For example, the eighth functional unit f8 multiplies the output frequency ω by an induced voltage coefficient λd to calculate the voltage required for the motor 70.

[0056] The eighth functional unit f8 specifies the correction value θc2 from the second phase correction function Fn2. For example, the eighth functional unit f8 assigns the acquired voltage Vx and the calculated voltage required for the motor 70 to the second phase correction function Fn2 to specify the value of the second phase correction function Fn2, i.e., the correction value θc2 (step S8). The eighth functional unit f8 outputs the specified correction value θc2 to the sixth functional unit f6.

[0057] The sixth functional unit f6 acquires the correction value θc2 output by the eighth functional unit f8. The sixth functional unit f6 also acquires the integration result output by the fourth functional unit f4. The sixth functional unit f6 adds the integration result and the correction value θc2 to calculate the addition result θes. That is, the sixth functional unit f6 changes the phase used in the three-phase to two-phase conversion to θes by adding the correction value θc2 to the phase used in the three-phase to two-phase conversion (step S9). The sixth functional unit f6 outputs the phase θes to the tenth functional unit f10.

[0058] The tenth functional unit f10 acquires the phase θes output by the sixth functional unit f6. The tenth functional unit f10 acquires the phase θes output by the sixth functional unit f6. The tenth functional unit f10 also acquires the motor current iu, the motor current iv, and the motor current iw output by the current detection circuit 110b. The tenth functional unit f10 converts the three-axis motor currents (i.e., the motor currents iu, iv, and iw) into two-axis motor currents (i.e., the inverter output currents id and the inverter output currents iq) using the phase θes (step S10). The tenth functional unit f10 outputs the two-axis motor currents to the first functional unit f1 and the third functional unit f3.

[0059] (Action and effect) The motor driving device 1 according to the first embodiment of the present disclosure has been described above. In the motor driving device 1, the eighth functional unit f8 (an example of a holding unit) holds the relationship between the fluctuation of the voltage supplied to the inverter 60 and a phase correction value. The correction value adding means (f6, f7) adds the correction value to at least one of the phase used when performing a 3-phase to 2-phase conversion that converts the three phases into two phases and the phase used when performing a 2-phase to 3-phase conversion that converts the two phases into the three phases.

[0060] As a result, in the motor drive device 1, the control device 90 can suppress torque fluctuations in the high speed range of the motor and also suppress rotation speed fluctuations. Furthermore, when torque fluctuations and rotation speed fluctuations can be suppressed, the current pulsation can be suppressed and the peak value of the current can be lowered compared to when the torque fluctuations and rotation speed fluctuations cannot be suppressed, so the control device 90 can suppress torque fluctuations and rotation speed fluctuations while suppressing a reduction in the operating range.

[0061] In another embodiment of the present disclosure, the correction value θc1 and the correction value θc2 may be the same.

[0062] It should be noted that the order of the processes in the embodiments of the present disclosure may be changed as long as appropriate processes are performed.

[0063] Each of the memory units and storage devices (including registers and latches) in the embodiments of the present disclosure may be provided anywhere within the range where appropriate information is transmitted and received. Furthermore, each of the memory units and storage devices may be present in multiple locations within the range where appropriate information is transmitted and received, and data may be stored in a distributed manner.

[0064] Although the embodiment of the present disclosure has been described, the above-mentioned control device 90 and other control devices may have a computer system inside. The above-mentioned process steps are stored in a computer-readable recording medium in the form of a program, and the above-mentioned process is performed by the computer reading and executing the program. Specific examples of computers are shown below. FIG. 7 is a schematic block diagram illustrating a computer configuration according to at least one embodiment. As shown in FIG. 7, the computer 5 includes a CPU 6, a main memory 7, a storage 8, and an interface 9. For example, the above-mentioned control device 90 and each of the other control devices are implemented in the computer 5. The operations of each of the above-mentioned processing units are stored in the storage 8 in the form of a program. The CPU 6 reads the program from the storage 8, loads it in the main memory 7, and executes the above-mentioned processing in accordance with the program. The CPU 6 also secures storage areas in the main memory 7 corresponding to each of the above-mentioned storage units in accordance with the program.

[0065] Examples of the storage 8 include a hard disk drive (HDD), a solid state drive (SSD), a magnetic disk, a magneto-optical disk, a compact disc read only memory (CD-ROM), a digital versatile disc read only memory (DVD-ROM), and a semiconductor memory. The storage 8 may be an internal medium directly connected to the bus of the computer 5, or an external medium connected to the computer 5 via an interface 9 or a communication line. In addition, when the program is distributed to the computer 5 via a communication line, the computer 5 that receives the program may load the program into the main memory 7 and execute the above-mentioned process. In at least one embodiment, the storage 8 is a non-transitory tangible storage medium.

[0066] The program may also realize some of the functions described above. Furthermore, the program may be a file that can realize the functions described above in combination with a program already recorded in the computer system, that is, a so-called differential file (differential program).

[0067] Although some embodiments of the present disclosure have been described, these embodiments are merely examples and do not limit the scope of the disclosure. Various additions, omissions, substitutions, and modifications may be made to these embodiments without departing from the spirit of the disclosure.

[0068] <Additional Notes> The control device 90 described in each embodiment of the present disclosure can be understood, for example, as follows.

[0069] (1) A control device (90) according to a first aspect of the present invention comprises: A means (f3) for setting a voltage command on two axes of a rotating orthogonal coordinate system, and a means (f5) for converting the voltage command on the two axes into a three-phase coordinate system; a means (110d) for applying the three-phase voltage command to the motor (70) after power conversion by an inverter (60); a means (110b) for feeding back a terminal current of the motor (70); A power factor angle determining means (f9) for determining a power factor angle from the current to be fed back; a power factor angle adjusting means (f10) for adjusting the power factor angle to a phase used when converting the terminal current of the motor (70) obtained in the three phases into an orthogonal coordinate system; A control device (90) for a motor (70) having a holding unit (f8) that holds a relationship between a fluctuation in a DC voltage supplied to the inverter (60) and a phase correction value; and a correction value adding means (f6, f7) for adding the correction value to at least one of a phase used when performing a 3-to-2-phase conversion for converting the three phases into two phases and a phase used when performing a 2-to-3-phase conversion for converting the two phases into the three phases.

[0070] In the control device (90), a holding unit (f8) holds the relationship between the fluctuation of the DC voltage supplied to the inverter (60) and a phase correction value. Correction value adding means (f6, f7) adds the correction value to at least one of a phase used when performing a three-phase to two-phase conversion for converting the three phases into two phases and a phase used when performing a two-phase to three-phase conversion for converting the two phases into the three phases.

[0071] This allows the control device (90) to change the command using the relationship between the DC voltage fluctuation and the phase correction value, thereby making it possible to suppress torque fluctuation, rotation speed fluctuation, and narrowing of the operating range of the motor (70) in the high-speed range even if a fluctuating voltage is input to the inverter (60).

[0072] (2) A control device (90) according to a second aspect is the control device (90) of (1), further comprising a detection unit (110a1) that detects the fluctuation, and determines the correction value based on the detection result of the detection unit (110a1).

[0073] This allows the control device (90) to change the command based on the result detected by the detection unit (110a1).As a result, even if voltage fluctuations occur frequently, the control device (90) can always detect the voltage after the fluctuations, and therefore, even if the fluctuated voltage is input to the inverter (60), torque fluctuations, rotation speed fluctuations, and narrowing of the operating range of the motor (70) in the high speed range can always be suppressed.

[0074] (3) A control device (90) according to a third aspect is the control device (90) of (1) or (2), and includes a calculation unit (110d) that generates a control command to control the inverter (60) based on the phase to which the correction value has been added.

[0075] As a result, the control device (90) is expected to generate a control command for the inverter (60) that can always suppress torque fluctuations, rotation speed fluctuations, and narrowing of the operating range of the motor (70) in the high-speed range, even if a fluctuating voltage is input to the inverter (60).

[0076] (4) A control device (90) according to a fourth aspect is the control device (90) of (3), in which the calculation unit (110d) generates a control command for controlling the inverter (60) based on the fluctuation.

[0077] As a result, the control device (90) is expected to generate a control command for the inverter (60) that can always suppress torque fluctuations, rotation speed fluctuations, and narrowing of the operating range of the motor (70) in the high-speed range, even if a fluctuating voltage is input to the inverter (60).

[0078] (5) A control device (90) according to a fifth aspect is the control device (90) of (4), wherein the calculation unit (110d) generates the control command based on a voltage required to drive a load (70) of the inverter (60).

[0079] As a result, the control device (90) is expected to generate control commands for the inverter (60) that can always suppress torque fluctuations, rotation speed fluctuations, and narrowing of the operating range of the motor (70) in the high-speed range, even when a fluctuating voltage is input to the inverter (60).

[0080] (6) A drive device for a motor (70) according to a sixth aspect includes the above-described control device and the inverter.

[0081] This allows the drive device of the motor (70) to change the command using the relationship between the DC voltage fluctuation and the phase correction value, thereby making it possible to suppress torque fluctuation, rotation speed fluctuation, and narrowing of the operating range of the motor (70) in the high-speed range even if a fluctuating voltage is input to the inverter (60).

[0082] (7) A drive device (1) for a motor (70) according to a seventh aspect is the drive device (1) for a motor (70) of (6), and includes the control device (90) and the inverter (60).

[0083] This allows the drive device (1) of the motor (70) to change the command using the relationship between the DC voltage fluctuation and the phase correction value, and as a result, even if a fluctuating voltage is input to the inverter (60), it is possible to suppress torque fluctuation, rotation speed fluctuation, and narrowing of the operating range of the motor (70) in the high-speed range.

[0084] (8) A control method according to an eighth aspect includes: a means (f3) for setting a voltage command on two axes of a rotating orthogonal coordinate system, a means (f5) for performing coordinate conversion of the two-axis voltage command to three phases, a means (110d) for applying the three-phase voltage command to the motor (70) after power conversion by an inverter (60), a means (110b) for feeding back a terminal current of the motor (70), a power factor angle determination means (f9) for determining a power factor angle from the current to be fed back, and a power factor angle adjustment means (f10) for adding / subtracting the power factor angle to / from a phase used when converting the terminal current of the motor (70) obtained in the three phases into an orthogonal coordinate system, maintaining a relationship between a fluctuation in a DC voltage supplied to the inverter (60) and a phase correction value; adding the correction value to at least one of a phase used when performing a three-phase to two-phase conversion for converting the three phases into two phases and a phase used when performing a two-phase to three-phase conversion for converting the two phases into the three phases; Includes.

[0085] In this manner, the control method can change the command using the relationship between the DC voltage fluctuation and the phase correction value, and as a result, even if a fluctuating voltage is input to the inverter (60), it is possible to suppress torque fluctuation, rotational speed fluctuation, and narrowing of the operating range of the motor (70) in the high speed range.

[0086] (9) A program according to a ninth aspect, a means (f3) for setting a voltage command on two axes of a rotating orthogonal coordinate system, a means (f5) for converting the two-axis voltage commands into three phases, a means (110d) for applying the three-phase voltage command to the motor (70) after power conversion by an inverter (60), a means (110b) for feeding back a terminal current of the motor (70), a power factor angle determination means (f9) for determining a power factor angle from the current to be fed back, and a power factor angle adjustment means (f10) for adding / subtracting the power factor angle to / from a phase used when converting the terminal current of the motor (70) obtained in the three phases into an orthogonal coordinate system, maintaining a relationship between a fluctuation in a DC voltage supplied to the inverter (60) and a phase correction value; adding the correction value to at least one of a phase used when performing a three-phase to two-phase conversion for converting the three phases into two phases and a phase used when performing a two-phase to three-phase conversion for converting the two phases into the three phases; Execute the command.

[0087] This allows the program to change the command using the relationship between the DC voltage fluctuation and the phase correction value, thereby making it possible to suppress torque fluctuation, rotational speed fluctuation, and narrowing of the operating range of the motor (70) in the high-speed range even if a fluctuating voltage is input to the inverter (60). [Explanation of symbols]

[0088] 1. Motor drive device 5. Computers 6. CPU 7. Main memory 8. Storage 9. Interface 10...Power supply 20. Converter 30...Reactor 40 1st capacitor 50 Second capacitor 60...Inverter 70 Motor 80 Current sensor 90... Control device 110a Voltage detection circuit 110a1, 110b1...A / D converter 110b Current detection circuit 110c: Voltage command generating unit 110d PWM duty calculation section f1...1st functional section f2: Second function section f3...Third functional section f4: Fourth functional part f5: Fifth function f6...6th functional section f7: 7th functional part f8...8th functional section f9: 9th function unit f10...10th functional section

Claims

1. A means for setting a voltage command on two axes of a rotating orthogonal coordinate system; A means for converting the two-axis voltage command into a three-phase coordinate system; a means for applying the three-phase voltage command to a motor through power conversion by an inverter; A means for feeding back a terminal current of the motor; a power factor angle determining means for determining a power factor angle from the terminal current to be fed back; a power factor angle adjusting means for adjusting the power factor angle to a phase used when converting the terminal current of the motor obtained in the three phases into an orthogonal coordinate system; In a control device for a permanent magnet synchronous motor having a holding unit that holds a relationship between a periodic fluctuation of a DC voltage supplied to the inverter by a capacitor connected to an input of the inverter and a phase correction value; a correction value adding means for adding the correction value to at least one of a phase used when performing a three-phase to two-phase conversion for converting the three phases into two phases corresponding to the two axes and a phase used when performing a two-phase to three-phase conversion for converting the two phases into the three phases; A control device comprising:

2. A detection unit that detects the fluctuation; Equipped with determining the correction value based on a detection result of the detection unit; The control device according to claim 1 .

3. a calculation unit that generates a control command for controlling the inverter based on the phase to which the correction value has been added; The control device according to claim 1 or 2, comprising:

4. The calculation unit is generating a control command for controlling the inverter based on the fluctuation; The control device according to claim 3.

5. The calculation unit is generating the control command based on a voltage required to drive a load of the inverter; The control device according to claim 4.

6. A control device according to any one of claims 1 to 5; The inverter; A motor drive device comprising:

7. a film capacitor provided at an input of the inverter to suppress fluctuations in the voltage supplied to the inverter; The motor drive device according to claim 6 .

8. 1. A control method for a permanent magnet synchronous motor using a control device comprising: means for setting voltage commands on two axes of a rotating orthogonal coordinate system; means for converting the two-axis voltage commands into three phases; means for applying the three-phase voltage commands to a motor via power conversion by an inverter; means for feeding back a terminal current of the motor; power factor angle determining means for determining a power factor angle from the fed back terminal current; and power factor angle adjusting means for adding / subtracting the power factor angle to / from a phase used when converting the terminal current of the motor obtained in the three phases into an orthogonal coordinate system, maintaining a relationship between a periodic fluctuation of a DC voltage supplied to the inverter by a capacitor connected to an input of the inverter and a phase correction value; adding the correction value to at least one of a phase used when performing a three-phase to two-phase conversion in which the three phases are converted into two phases corresponding to the two axes and a phase used when performing a two-phase to three-phase conversion in which the two phases are converted into the three phases; A control method comprising:

9. a computer for a control device for a permanent magnet synchronous motor, the computer comprising: means for setting voltage commands on two axes of a rotating orthogonal coordinate system; means for converting the two-axis voltage commands into three phases; means for applying the three-phase voltage commands to a motor via power conversion by an inverter; means for feeding back a terminal current of the motor; a power factor angle determining means for determining a power factor angle from the fed back terminal current; and a power factor angle adjusting means for adjusting the power factor angle to a phase used when converting the terminal current of the motor obtained in the three phases into an orthogonal coordinate system, maintaining a relationship between a periodic fluctuation of a DC voltage supplied to the inverter by a capacitor connected to an input of the inverter and a phase correction value; adding the correction value to at least one of a phase used when performing a three-phase to two-phase conversion in which the three phases are converted into two phases corresponding to the two axes and a phase used when performing a two-phase to three-phase conversion in which the two phases are converted into the three phases; A program that executes the following.

10. A means for setting a voltage command on two axes of a rotating Cartesian coordinate system; A means for converting the two-axis voltage command into a three-phase coordinate system; a means for applying the three-phase voltage command to a motor through power conversion by an inverter; A means for feeding back a terminal current of the motor; In a control device for a permanent magnet synchronous motor having a holding unit that holds a relationship between a periodic fluctuation of a DC voltage supplied to the inverter by a capacitor connected to an input of the inverter and a phase correction value; a correction value adding means for adding the correction value to at least one of a phase used when performing a three-phase to two-phase conversion for converting the three phases into two phases corresponding to the two axes and a phase used when performing a two-phase to three-phase conversion for converting the two phases into the three phases; A control device comprising:

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