Motor control units, motors, compressors, refrigeration systems, and vehicles.

Abstract

DEPCT67 A motor control unit designed to convert the input power fed from the power source. The power is supplied as an alternating current output with a predetermined voltage and frequency. As predetermined, the motor control unit will consist of an inversion circuit which is... It is configured to supply AC power to the motor and is designed to operate. Controlled to suppress the amplitude of the first harmonic component, which occurs in rhythm with the rate. The motor rotates under a power condition where the power supplied to the motor is lower than or equal to a predetermined value. Predetermined and designed to suppress the amplitude of the second harmonic component that arises in the force. To reduce the electromagnetic interference of the motor at the same frequency to a level lower than the first harmonic component. The amplitude of the second harmonic component in the case where the amplitude of the first harmonic component is equal. Suspended to the lowest level;

Description

Motor control device, motor, compressor, refrigeration device and vehicle

[0001] The present disclosure relates to a motor control device, a motor, a compressor, a refrigeration device, and a vehicle.

[0002] A motor drive control device is known that converts a constant DC voltage from a DC power supply into an arbitrary pseudo three-phase AC voltage using a three-phase bridge circuit to drive a three-phase motor with a permanent magnet in the rotor. This motor drive control device detects the average value of the DC current in the three-phase bridge circuit and controls the desired current value of the rotation control system so that the component of the detected average value that is six times the current frequency of the three-phase motor is reduced, thereby reducing the torque ripple of the motor (see, for example, Patent Document 1).

[0003] JP 2010-88228 A

[0004] If harmonic components are contained in the induced voltage of the motor, harmonic components will also be generated in the input power to the motor, and harmonics of the same order as the harmonic components generated in the input power to the motor may be generated in the DC part on the input side of the inverter circuit that supplies power to the motor.

[0005] However, even if the harmonic components occurring in the input power of the motor are reduced, there are cases where the harmonic components occurring in the electromagnetic excitation force, such as torque ripple of the motor, cannot be reduced.

[0006] The present disclosure provides a motor control device and a motor that are capable of reducing harmonic components that occur in the input power of the motor and harmonic components that occur in the electromagnetic excitation force of the motor.

[0007] The present disclosure provides a motor control device that converts input power supplied from a power source into output AC power of a predetermined voltage and frequency, comprising an inverter circuit that supplies the output AC power to a motor, and that performs control to suppress the amplitude of a first harmonic component that occurs in the input power of the motor in synchronization with the rotation speed of the motor to be equal to or less than a predetermined value, and to reduce the amplitude of a second harmonic component that occurs in the electromagnetic excitation force of the motor at the same frequency as the first harmonic component, compared to when the amplitude of the first harmonic component is suppressed to the smallest.

[0008] This makes it possible to reduce harmonic components occurring in the input power of the motor and harmonic components occurring in the electromagnetic excitation force of the motor.

[0009] In the motor control device, the power supply may be an AC power supply.

[0010] This reduces the harmonics that flow into the AC power supply.

[0011] In the motor control device, the frequencies of the first harmonic component and the second harmonic component may be a multiple of six of a fundamental frequency of the input voltage to the motor.

[0012] This makes it possible to reduce harmonic components (harmonic components having frequencies that are six times the fundamental frequency of the input voltage of the motor) that occur in the input power and electromagnetic excitation force of the motor.

[0013] The motor control device may further include a control unit that performs the control, wherein the control unit may superimpose a compensation amount that changes in synchronization with the rotation speed of the motor on an operation amount of the motor control device.

[0014] This makes it possible to easily reduce the harmonic components occurring in the input power of the motor and the harmonic components occurring in the electromagnetic excitation force of the motor.

[0015] In the motor control device, the manipulated variable may be at least one of a modulation factor of the inverter circuit, an amplitude of a voltage vector of an input voltage to the motor, a phase of the voltage vector, an amplitude of a current vector of an input current to the motor, and a phase of the current vector.

[0016] This makes it possible to more easily reduce the harmonic components occurring in the input power of the motor and the harmonic components occurring in the electromagnetic excitation force of the motor.

[0017] In the above motor control device, the control unit may detect a value correlated with the first harmonic component, and determine at least one of the amplitude and phase of the compensation amount based on the relationship between the first harmonic component and the second harmonic component.

[0018] This makes it possible to easily reduce the harmonic components occurring in the input power of the motor and the harmonic components occurring in the electromagnetic excitation force of the motor.

[0019] In the above motor control device, the control unit may detect a value correlated with the second harmonic component, and determine at least one of the amplitude and phase of the compensation amount based on the relationship between the first harmonic component and the second harmonic component.

[0020] This makes it possible to easily reduce the harmonic components occurring in the input power of the motor and the harmonic components occurring in the electromagnetic excitation force of the motor.

[0021] In the motor control device, the relationship may be held in the form of a table or an equation.

[0022] This makes it possible to easily reduce the harmonic components occurring in the input power of the motor and the harmonic components occurring in the electromagnetic excitation force of the motor.

[0023] In the motor control device, the control unit may detect a value correlated with the first harmonic component and a value correlated with the second harmonic component, and determine at least one of the amplitude and phase of the compensation amount.

[0024] This makes it possible to easily reduce the harmonic components occurring in the input power of the motor and the harmonic components occurring in the electromagnetic excitation force of the motor.

[0025] In the motor control device, the control unit may determine at least one of the amplitude and phase of the compensation amount using a stored table or equation.

[0026] This makes it possible to easily reduce the harmonic components occurring in the input power of the motor and the harmonic components occurring in the electromagnetic excitation force of the motor.

[0027] In the above motor control device, when the control is performed, the magnitude of fluctuation of the frequency component of the stored energy of the motor, which is the same as the first harmonic component, may be smaller than the magnitude of fluctuation of the frequency component of the output energy due to the torque of the motor, which is the same as the second harmonic component.

[0028] This makes it possible to easily reduce the harmonic components occurring in the input power of the motor and the harmonic components occurring in the electromagnetic excitation force of the motor.

[0029] The present disclosure provides a motor controlled by a motor control device that suppresses a first harmonic component that occurs in the input power of the motor in synchronization with the rotation speed of the motor, or a second harmonic component that occurs in the electromagnetic excitation force of the motor at the same frequency as the first harmonic component, wherein when the suppression is performed, the magnitude of fluctuation of the frequency component that is the same as the first harmonic component in the stored energy of the motor is smaller than the magnitude of fluctuation of the frequency component that is the same as the second harmonic component in the output energy due to the torque of the motor.

[0030] This makes it possible to reduce harmonic components occurring in the input power of the motor and harmonic components occurring in the electromagnetic excitation force of the motor.

[0031] The above motor may be a surface permanent magnet synchronous motor including a rotor and a stator, wherein the rotor has a rotor core and a plurality of magnets arranged in the circumferential direction of the rotor core.

[0032] This makes it possible to reduce harmonic components occurring in the input power of the motor and harmonic components occurring in the electromagnetic excitation force of the motor.

[0033] The above motor may be an interior permanent magnet synchronous motor having a rotor and a stator, wherein the rotor has a rotor core and a plurality of magnets, the rotor core has a plurality of magnet insertion holes, and a magnetic resistance portion is provided to obstruct the main magnetic flux of the magnets.

[0034] This makes it possible to reduce harmonic components occurring in the input power of the motor and harmonic components occurring in the electromagnetic excitation force of the motor.

[0035] The present disclosure provides a compressor driven by the above motor.

[0036] This makes it possible to provide a compressor equipped with a motor that can reduce harmonic components generated in the input power of the motor and harmonic components generated in the electromagnetic excitation force of the motor.

[0037] The present disclosure provides a refrigeration device including the above compressor.

[0038] This makes it possible to provide a refrigeration system equipped with a compressor incorporating a motor that can reduce harmonic components generated in the input power of the motor and harmonic components generated in the electromagnetic excitation force of the motor.

[0039] The present disclosure provides a vehicle equipped with the above motor.

[0040] This makes it possible to provide a vehicle equipped with a motor that can reduce harmonic components generated in the input power of the motor and harmonic components generated in the electromagnetic excitation force of the motor.

[0041] 1 is a graph illustrating harmonics occurring in a power supply current.

[0023] FIG. 1 is an example of the results of analyzing the magnitudes of harmonics occurring in the input power of a motor (motor input power harmonics) and motor torque ripple when the amplitude and phase of a fifth-order harmonic superimposed on the phase current of the motor are changed.

[0024] FIG. 1 is an example of the results of deriving, from magnetic field analysis, the power and output (= torque × rotation speed) relative to the electrical angle of a motor.

[0025] FIG. 2 is a diagram for explaining a motor control method, which is one of the techniques disclosed herein, for reducing harmonic components occurring in the input power of a motor and harmonic components occurring in the electromagnetic excitation force of a motor.

[0026] FIG. 3 is a diagram for explaining a motor structure, which is one of the techniques disclosed herein, for reducing harmonic components occurring in the input power of a motor and harmonic components occurring in the electromagnetic excitation force of a motor.

[0027] FIG. 4 is a diagram illustrating a first configuration example of a motor control device.

[0028] FIG. 5 is a diagram for explaining the derivation of a compensation amount to be superimposed on a manipulation amount of the motor control device.

[0029] FIG. 6 is a block diagram illustrating a first configuration example of a control unit.

[0030] FIG. 7 is an example of the results of deriving, from magnetic field analysis, the power and output (= torque × rotation speed) relative to the electrical angle of a motor. 1 is a cross-sectional view illustrating a surface permanent magnet synchronous motor having a rotor and a stator; 2 is a cross-sectional view illustrating an interior permanent magnet synchronous motor having a rotor and a stator; 3 is a diagram illustrating an example of a refrigeration device including a motor controlled by the motor control device of the embodiment or a compressor driven by the motor of the embodiment; 4 is a diagram illustrating an example of a vehicle equipped with a motor controlled by the motor control device of the embodiment or the motor of the embodiment.

[0042] The embodiments will be described below: First, harmonics generated on the input side of the inverter circuit will be described.

[0043] Because the magnetomotive force and gap permeance of a motor change depending on the rotational position of the motor, the magnetic flux linkage changes in synchronization with the motor's rotation speed, and the induced voltage of the motor may contain harmonic components such as five or seven times the fundamental frequency. If these harmonic components are included in the induced voltage of the motor, harmonic components with frequencies that are six times the fundamental frequency of the induced voltage may appear in the input power to the motor.

[0044] For example, when using a motor control device that does not have an internal energy storage element, such as a capacitorless inverter, harmonic components may be generated in the motor's input power, resulting in harmonics of the same order as the harmonic components generated in the motor's input power being generated in the power at the input side of the inverter circuit. If these harmonics flow into the AC power supply on the input side of the inverter circuit, the current on the power supply side will contain harmonics (power supply harmonics) with frequencies equal to or greater than the frequency of the motor's input power plus or minus the power supply voltage. Therefore, it is necessary to reduce the harmonic components of the motor's input power so that each power supply harmonics generated by the harmonic components of the motor's input power are below the power supply harmonic regulation value. Furthermore, even in the case of DC power sources such as automotive batteries, harmonic currents with the frequency of the motor's input power are generated on the input side. Because harmonic currents accelerate battery degradation, it is necessary to reduce the harmonics of the motor's input power, just as with AC power sources.

[0045] Fig. 1 is a graph illustrating harmonics generated on the input side of a power conversion circuit, with the horizontal axis representing the harmonic order (multiples of the power supply voltage frequency). Fig. 1 illustrates that the 30th and 32nd power supply harmonics are power supply harmonics resulting from harmonic components generated in the motor's input power and exceed the power supply harmonic regulation value. In this case, it is necessary to reduce the harmonic components of the motor's input power so that the 30th and 32nd power supply harmonics are equal to or less than the power supply harmonic regulation value.

[0046] On the other hand, as described above, the technology of Patent Document 1 detects the average value of the current in the DC portion of the three-phase bridge circuit and controls the current so that the component of the detected average value that is six times the current frequency of the three-phase motor is reduced, thereby reducing the torque ripple of the motor.

[0047] Here, we used magnetic field analysis to confirm whether superimposing a harmonic compensation waveform on the current reduces both the harmonics generated in the motor's input power and the motor's torque ripple, and obtained the results shown in Figure 2. Figure 2 shows an example of the results of analyzing the magnitude of the harmonics generated in the motor's input power (motor input power harmonics) and the motor's torque ripple when the amplitude and phase of the fifth harmonic (equivalent to the sixth harmonic generated in the motor's input power) superimposed on the motor's phase current is changed.

[0048] As shown in Figure 2, the amplitude and phase of the compensation current waveform that minimizes the motor input power harmonics are different from the amplitude and phase of the compensation current waveform that minimizes the torque ripple. Furthermore, in the current waveform that minimizes the magnitude of the motor input power harmonics when the fifth harmonic is superimposed, the magnitude of the torque ripple is slightly larger than in the case of a sinusoidal current without the fifth harmonic superimposed. Thus, even if a harmonic compensation waveform that reduces the motor input power harmonics is superimposed, there are cases where the motor torque ripple cannot be reduced.

[0049] Let's consider this point. If we ignore losses, we believe that the equation "power = torque x rotation speed" holds true for the average value of power. However, as shown in Figure 3, when we perform a magnetic field analysis, we find that the waveform of the power supplied to the motor does not match the waveform of the motor's output (= torque x rotation speed), and therefore the equation "power = torque x rotation speed" does not hold true for the instantaneous value of power. We believe that this is because the motor's coils store instantaneous energy. The energy stored instantaneously in this motor's coils is called the motor's stored energy.

[0050] Figure 3 shows an example of the results of magnetic field analysis of the power and output (= torque x rotation speed) versus the motor's electrical angle. Losses are ignored in Figure 3. As shown in Figure 3, the waveform of the power supplied to the motor and the waveform of the motor's output match in average power, but do not match in instantaneous power values. Therefore, it can be said that simply minimizing the motor's input power harmonics does not necessarily reduce motor torque ripple.

[0051] The technology disclosed herein reduces both harmonic components generated in the input power of a motor (motor input power harmonics) and harmonic components generated in the electromagnetic excitation force of a motor (electromagnetic excitation force harmonics). The electromagnetic excitation force includes a rotational component (circumferential component), a radial component, and an axial component, and torque ripple corresponds to the harmonic components of the rotational component of the electromagnetic excitation force.

[0052] FIG. 4 is a diagram for explaining a motor control method, which is one of the techniques disclosed herein, for reducing motor input power harmonics and electromagnetic excitation force harmonics.

[0053] The motor control method disclosed herein reduces motor input power harmonics and electromagnetic excitation force harmonics by suppressing the amplitude of motor input power harmonics to a predetermined value or less and reducing the amplitude of electromagnetic excitation force harmonics having the same frequency as the motor input power harmonics compared to when the amplitude of the motor input power harmonics is minimized. The motor input power harmonics are an example of first harmonic components that occur in the motor's input power in synchronization with the motor's rotation speed. The electromagnetic excitation force harmonics having the same frequency as the motor input power harmonics are an example of second harmonic components that occur in the motor's electromagnetic excitation force at the same frequency as the first harmonic components. According to the motor control method disclosed herein, by setting a predetermined value as the limit value for the harmonic components of the motor input power calculated from the power supply harmonic regulation value, power supply harmonics can be reduced to a value below the power supply harmonic regulation value and the amplitude of the electromagnetic excitation force harmonics can be reduced below a value below the power supply harmonic regulation value.

[0054] Note that "when the amplitude of the first harmonic component (in this example, the motor input power harmonic) is suppressed to the smallest value" refers to when the amplitude of the first harmonic component is suppressed to a minimum value by controlling the motor. If there are multiple minimum values, the minimum value may be the smallest of the multiple minimum values. Theoretically, the minimum value is the value (zero) when the harmonic is completely suppressed, but it may not become zero due to control limits. FIG. 4 illustrates an example of a state in which the amplitude of the electromagnetic excitation force harmonic is suppressed to an amplitude value b2, which is smaller than the amplitude value b1 when the amplitude of the motor input power harmonic is suppressed to the smallest amplitude value a1. In the example shown in FIG. 4, the amplitude of the motor input power harmonic is suppressed to an amplitude value a2 so as not to exceed a reference value, and the amplitude of the electromagnetic excitation force harmonic is suppressed to an amplitude value b2.

[0055] 5 is a diagram illustrating a motor structure that is one of the techniques disclosed herein for reducing motor input power harmonics and electromagnetic excitation force harmonics. As described above, it is difficult to reduce the amplitude of electromagnetic excitation force harmonics simply by minimizing the amplitude of motor input power harmonics.

[0056] The motor disclosed herein has a motor structure in which the conditions for minimizing the amplitude of the motor input power harmonics and the conditions for minimizing the amplitude of the electromagnetic excitation force harmonics are close to each other. With this motor structure, the amplitude of the electromagnetic excitation force harmonics can be reduced by reducing the amplitude of the motor input power harmonics. For example, the motor disclosed herein has a motor structure in which the phase difference between the compensation waveform that minimizes the amplitude of the motor input power harmonics and the compensation waveform that minimizes the amplitude of the electromagnetic excitation force harmonics is less than 90°. With this motor structure, as shown in FIG. 5 , reducing the amplitude of the motor input power harmonics to amplitude value a1 reduces the amplitude of the electromagnetic excitation force harmonics from amplitude value b1 to amplitude value b3.

[0057] To achieve a motor structure that meets the conditions for minimizing the amplitude of the motor input power harmonics and the electromagnetic excitation force harmonics, it is preferable to make the motor inductance as small as possible so that the energy stored in the motor coil is small. To reduce inductance, it is effective to use a motor with a reduced number of coil turns or a surface permanent magnet synchronous motor.

[0058] Next, a configuration example of a motor control device to which the technology of the present disclosure is applied will be described.

[0059] Fig. 6 is a block diagram showing a first configuration example of a motor control device to which the technology of the present disclosure is applied. The motor control device 1A shown in Fig. 6 includes a converter circuit 2, a DC link unit 3, an inverter circuit 4, and a control unit 5, and converts input AC power supplied from a three-phase AC power supply 6 into output AC power of a predetermined voltage and a predetermined frequency, and supplies the output AC power to a motor 7.

[0060] The motor 7 is, for example, a three-phase AC motor. Specific examples of the motor 7 include an electric motor that drives a compressor provided in the refrigerant circuit of an air conditioner. The motor 7 is, for example, a concentrated winding motor such as a 4-pole, 6-slot or 6-pole, 9-slot motor. The harmonic components of the induced voltage of this motor 7 tend to include many 5th and 7th order components of the fundamental frequency. Higher order (e.g., 6th order) harmonic components resulting from this motor voltage distortion (5th and 7th order harmonic components of the fundamental frequency) may appear in the input power of the motor 7 and on the input side of the inverter circuit 4. These higher order harmonic components are generated by the power supply current i of the AC power supply 6. ｉｎ , the DC link voltage v in the DC link section 3 ｄｃ , reactor voltage v across reactor 8 Ｌ , the reactor current i flowing through the reactor 8 Ｌ , or the DC current i flowing through the DC link section 3 ｄｃ It may appear in.

[0061] The converter circuit 2 is connected to an AC power supply 6 and converts the AC output from the AC power supply 6 into DC. The converter circuit 2 is, for example, a diode bridge circuit in which a plurality of diodes (six in this example) are connected in a bridge configuration. These diodes full-wave rectify the AC voltage of the AC power supply 6 and convert it into a DC voltage. The converter circuit 2 may be a voltage conversion circuit of a circuit type other than a diode bridge, as long as it supplies the converted DC power to the inverter circuit 4 via the DC link unit 3.

[0062] The DC link unit 3 includes a capacitor 3a connected between the converter circuit 2 and the inverter circuit 4. The capacitor 3a is connected in parallel to the output of the converter circuit 2, and a DC voltage (DC link voltage v ｄｃ ) is input to the input node of the inverter circuit 4. The capacitor 3a will be further described later.

[0063] The DC link unit 3 includes a reactor 8 connected between the converter circuit 2 and the inverter circuit 4. The reactor 8 is inserted in series in a DC bus between the output of the converter circuit 2 and the input of the inverter circuit 4.

[0064] The inverter circuit 4 has an input node connected in parallel to the capacitor 3a of the DC link unit 3, and switches the output of the DC link unit 3 to convert it into three-phase AC and supply it to the connected motor 7. In this embodiment, the inverter circuit 4 is configured with a plurality of switching elements connected in a bridge connection. Since the inverter circuit 4 outputs three-phase AC to the motor 7, it has six switching elements. More specifically, the inverter circuit 4 has three switching legs connected in parallel, and each switching leg has two switching elements connected in series. In each switching leg, the midpoint between the upper arm switching element and the lower arm switching element is connected to the coil of each phase of the motor 7. In addition, a freewheeling diode is connected in anti-parallel to each switching element. The inverter circuit 4 converts the DC link voltage v input from the DC link unit 3 into a DC link voltage v , by the on / off operation of these switching elements. ｄｃ is switched to convert it into a three-phase AC voltage and supplied to the motor 7. The control unit 5 controls this on / off operation.

[0065] The control unit 5 controls the amplitude of a first harmonic component that occurs in the input power of the motor 7 in synchronization with the rotation speed of the motor 7 to be equal to or less than a predetermined value, and controls the amplitude of a second harmonic component that occurs in the electromagnetic excitation force of the motor 7 at the same frequency as the first harmonic component to be smaller than when the amplitude of the first harmonic component is minimized. The control unit 5 controls the switching (on / off operation) of the inverter circuit 4 so that the amplitudes of the first harmonic component and the second harmonic component are suppressed in this manner.

[0066] 7 is a diagram showing a second configuration example of a motor control device to which the technology of the present disclosure is applied. Description of the same configuration as in the first configuration example will be omitted, as the above description is incorporated herein. The motor control device 1B shown in FIG. 7 includes a converter circuit 2, a DC link unit 3, an inverter circuit 4, and a control unit 5, and converts input AC power supplied from a single-phase AC power supply 6 into output AC power of a predetermined voltage and a predetermined frequency, and supplies the converted power to a motor 7.

[0067] The converter circuit 2 is connected to the AC power supply 6 via a reactor 8 and rectifies (converts) the AC output from the AC power supply 6 into DC. The converter circuit 2 is, for example, a diode bridge circuit in which a plurality of diodes (four in this example) are connected in a bridge configuration. These diodes full-wave rectify the AC voltage of the AC power supply 6 and convert it into a DC voltage. The converter circuit 2 may be a voltage conversion circuit of a circuit type other than a diode bridge, as long as it supplies the converted DC power to the inverter circuit 4 via the DC link unit 3.

[0068] The reactor 8 is connected between the AC power supply 6 and the converter circuit 2, and more specifically, is inserted in series between the AC output side of the AC power supply 6 and the AC input side of the converter circuit 2.

[0069] 6 and 7, the capacitance value of the capacitor 3a is such that it can hardly smooth the output of the converter circuit 2, while it can suppress the ripple voltage (switching frequency f ｃSpecifically, the capacitor 3a is configured as a small-capacity capacitor (for example, a film capacitor) having a capacitance value (for example, on the order of several tens to several hundreds of μF) that is approximately 0.01 times the capacitance value of a smoothing capacitor (for example, an electrolytic capacitor) used to smooth the output of the converter circuit 2 in a general power conversion device or motor control device.

[0070] Since the capacitance value of the capacitor 3a is so small, the output of the converter circuit 2 is hardly smoothed in the DC link unit 3, and as a result, the power supply voltage v of the AC power supply 6 ｉｎ The pulsating component corresponding to the frequency of the DC voltage (DC link voltage v ｄｃ ) remains. For example, the DC link voltage v ｄｃ In the case of the three-phase AC power supply 6 shown in FIG. ｉｎ In the case of the single-phase AC power supply 6 of FIG. 7, the power supply voltage v ｉｎ It has a pulsating component with a frequency twice that of the frequency of the

[0071] Furthermore, when the power conversion device uses not only the capacitor 3a but also the reactor 8, an LC filter is formed by the reactor 8 and the capacitor 3a. The resonant frequency f ｒ is the commercial frequency f of the N-phase AC power supply 6. ｉｎ The inductance of the reactor 8 and the capacitance of the capacitor 3 a are set so that the frequency is N times or more of the frequency of the inverter circuit 4 and the ripple voltage caused by the switching operation of the inverter circuit 4 is attenuated.

[0072] N × f ｉｎ ≦f ｒ ≦f ｃ / 4 f ｒ =1 / (2π√(LC)) where L represents the inductance of the reactor 8, and C represents the capacitance of the capacitor 3a.

[0073] When the motor control device is a capacitor-less inverter (more specifically, an electrolytic capacitor-less inverter) in which the capacitance value of the capacitor 3a in the DC link unit 3 is thus small, there is a risk that harmonics caused by distortion components (harmonic components) occurring in the input power of the motor 7 will leak out to the power supply. Similarly, when the motor control device is a matrix converter, there is a risk that harmonics caused by distortion components occurring in the input power of the motor will leak out to the power supply.

[0074] The control unit 5 illustrated in Figure 6 or 7 performs control to suppress the amplitude of a first harmonic component that occurs in the input power of the motor 7 in synchronization with the rotation speed of the motor 7 to a predetermined value or less, and to reduce the amplitude of a second harmonic component that occurs in the electromagnetic excitation force of the motor 7 at the same frequency as the first harmonic component, compared to when the amplitude of the first harmonic component is suppressed to the smallest possible value. This control is also referred to as harmonic suppression control. This harmonic suppression control reduces the amplitudes of the first harmonic component and the second harmonic component, thereby reducing harmonics generated on the input side of the inverter circuit 4 (e.g., power supply harmonics flowing to the power supply side) and vibrations caused by the electromagnetic excitation force.

[0075] The control unit 5 superimposes, for example, a compensation amount C that changes in synchronization with the rotation speed of the motor 7 on the operation amount D of the motor control device exemplified in Fig. 6 or 7. This makes it possible to easily reduce the amplitudes of the first harmonic component and the second harmonic component.

[0076] The control unit 5 detects, for example, by Fourier transform or the like, a value f that correlates with the first harmonic component that occurs in the input power of the motor 7 in synchronization with the rotation speed of the motor 7. Harmonics of the same order as the sixth-order harmonic component that occurs in the input power of the motor also occur in the power on the input side of the inverter circuit. Therefore, the value f that correlates with the first harmonic component that occurs in the input power of the motor 7 in synchronization with the rotation speed of the motor 7 is, for example, the reactor voltage v Ｌ , reactor current i Ｌ , DC link voltage v ｄｃ , DC current i ｄｃ or power supply current i ｉｎ is the amplitude of the harmonic components generated in synchronization with the rotation speed of the motor 7. Ｌ , reactor current i Ｌ , DC link voltage vｄｃ , DC current i ｄｃ The harmonic components generated in synchronization with the rotation speed of the motor 7 have the same frequency as the first harmonic component, for example. ｉｎ The harmonic components generated in synchronization with the rotation speed of the motor 7 have, for example, the frequency of the first harmonic component ± the frequency of the power supply voltage.

[0077] The control unit 5 detects a value f that correlates with a first harmonic component that occurs in the input power of the motor 7 in synchronization with the rotation speed of the motor 7, and derives at least one of the amplitude and phase of the correction amount C that minimizes the detected value f. Based on the relationship between the first harmonic component and the second harmonic component, the control unit 5 corrects at least one of the amplitude and phase of the correction amount C that minimizes the detected value f so that the amplitude of the first harmonic component becomes equal to or smaller than the reference value REF and the amplitude of the second harmonic component becomes smaller. In the example shown in FIG. 8 , the control unit 5 calculates the phase θ of the compensation amount C. Ｃ θ Ｃ１ From θ Ｃ２ Correct to.

[0078] The relationship between the first harmonic component and the second harmonic component is defined by data for determining at least one of the amplitude and phase of the correction amount C so that the amplitude of the first harmonic component is equal to or less than the reference value REF and the amplitude of the second harmonic component is reduced. This relationship is stored in memory in the form of a pre-calculated table or formula.

[0079] Next, a configuration example of the control unit 5 that performs harmonic suppression control will be described.

[0080] Fig. 9 is a block diagram showing a first configuration example of a control unit. A control unit 5A shown in Fig. 9 is an example of the control unit 5. The control unit 5A outputs a gate control signal G to the inverter circuit 4, which controls the on / off operation of each switching element in the inverter circuit 4. The control unit 5A includes a motor control unit 11, a compensation unit 20, and a PWM calculation unit 12.

[0081] The functions of the control unit 5A are realized by a processor such as a CPU (Central Processing Unit) operating according to a program readably stored in a memory. The functions of the units may also be realized by a FPGA (Field Programmable Gate Array) or an ASIC (Application Specific Integrated Circuit).

[0082] The motor control unit 11 generates and outputs the phase of the AC voltage output from the inverter circuit 4 (voltage phase δ [°]) and the voltage control rate K of the inverter circuit 4. The voltage control rate is also called a modulation rate. ＊ The superscript "*" in the above indicates the command value. The unit symbol in [ ] indicates an example of the unit.

[0083] The motor control unit 11 includes, for example, a speed control unit 14, a current command generation unit 15, a current control unit 16, an adder 13, and a modulation factor calculation unit 17. The speed control unit 14 calculates a command rotation speed ω of the motor 7. ｅ ＊ [rad / s] and the detected rotation speed ω of the motor 7 ｅ [rad / s], the command torque T of the motor 7 is set to zero. ＊ The current command generator 15 generates a command torque T ＊ Based on this, the amplitude I of the current vector of the input current of the motor 7 ａ ＊ [A] and phase β ＊ The current control unit 16 generates the amplitude I of the current vector. ａ ＊ and phase β ＊ and the d-axis current i of the motor 7 ｄ and q-axis current i ｑ Based on this, the amplitude V of the voltage vector of the input voltage (for example, line voltage) of the motor 7 is calculated. ａ ＊ [V] and phase δ ０ ＊ Generate [°]. δ ０ ＊ represents the zero-order component of the voltage phase δ. The adder 13 calculates the zero-order component of the voltage vector phase δ. ０＊ The command value δ of the voltage phase δ is obtained by adding the compensation amount C generated by the compensation unit 20 to the ＊ In this way, in the example shown in FIG. 9, the compensation amount C that changes in synchronization with the rotation speed of the motor 7 is superimposed on the voltage phase δ, which is an example of the manipulated variable D. The modulation factor calculation unit 17 calculates the amplitude V of the voltage vector. ａ ＊ and DC link voltage v ｄｃ and the command value K of the voltage control rate K ＊ Here, the detected rotation speed and the command rotation speed may be either a mechanical angular speed or an electrical angular speed. Note that the electrical angular speed is obtained by multiplying the mechanical angular speed by the number of pole pairs of the motor, and the mechanical angular speed is the rotation speed of the motor expressed as an angle advanced per unit time.

[0084] The compensator 20 calculates a compensation amount C for compensating for harmonics in the input power of the motor 7. The compensator 20 includes, for example, a reference phase calculator 22, a compensation phase calculator 21, an adder 24, a waveform generator 25, an amplitude calculator 26, and a multiplier 27.

[0085] In the example shown in FIG. 9, the reference phase calculation unit 22 calculates the reactor voltage v Ｌ The amplitude of the harmonic components generated in synchronization with the rotation speed of the motor 7 is detected by Fourier transform or the like as a value f that correlates with the motor input power harmonics generated in synchronization with the rotation speed of the motor 7 in the input power of the motor 7. The reference phase calculation unit 22 calculates the detected reactor voltage v Ｌ The reference phase θ that minimizes the amplitude of the harmonic components of ｖＬ＿ｍｉｎ is calculated using the hill-climbing method or the like.

[0086] The compensation phase calculation unit 21 calculates the detected rotation speed ω of the motor 7. ｅ , the command rotation speed ω of the motor 7 ｅ ＊ and the input power P of the motor 7 ｉｎ０ The reference phase θ ｖＬ＿ｍｉｎ Compensation phase θ ｃｏｍ The input power P ｉｎ０ represents, for example, the average value of the input power. The compensation phase calculation unit 21 calculates, for example, the detected rotation speed ωｅ and compensation phase θ ｃｏｍ Based on the correlation with the detected rotation speed ω ｅ The compensation phase θ corresponding to ｃｏｍ The correlation whereby the amplitude of the electromagnetic excitation force harmonics generated at the same frequency as the motor input power harmonics is equal to or less than a predetermined threshold is, for example, a relational law determined in advance by testing or the like, and is defined by a look-up table, an arithmetic expression, or the like. Similarly, the detected rotation speed ω ｅ The command speed ω ｅ ＊ or input power P ｉｎ０ Even if the above correlation is used, an appropriate compensation phase θ ｃｏｍ is obtained.

[0087] The adder 24 calculates the reference phase θ ｖＬ＿ｍｉｎ Compensation phase θ ｃｏｍ By adding δ Calculate.

[0088] The waveform generator 25 generates a rotation angle 6θ that is six times the electrical angle of the motor 7. ｅ Correction phase θ δ Adding these, we get the periodic waveform cos(6θ ｅ +θ δ ) to generate the

[0089] The amplitude calculation unit 26 calculates the detected rotation speed ω of the motor 7. ｅ , the command rotation speed ω of the motor 7 ｅ ＊ and the input power P of the motor 7 ｉｎ０ The amplitude δ of the compensation amount C is determined according to at least one of the following: ６ The amplitude calculation unit 26 calculates, for example, the detected rotation speed ω at which the amplitude of the motor input power harmonic and the amplitude of the electromagnetic vibration force harmonic generated at the same frequency as the motor input power harmonic are equal to or smaller than a predetermined threshold. ｅ and amplitude δ ６ Based on the correlation with the detected rotation speed ω ｅ The amplitude δ corresponding to ６The correlation between the amplitude of the motor input power harmonic and the amplitude of the electromagnetic excitation force harmonic generated at the same frequency as the motor input power harmonic is equal to or less than a predetermined threshold value, and is a relational law determined in advance by testing, for example, and is defined by a look-up table, an arithmetic expression, or the like. Similarly, the detected rotation speed ω ｅ The output torque T ｅ or input power P ｉｎ０ Even if we replace ６ is obtained.

[0090] The multiplier 27 multiplies cos(6θ ｅ +θ δ ) and amplitude δ ６ By multiplying this, the compensation amount C (= δ ６ sin (6θ ｅ +θ δ ) is calculated by the motor control unit 11. ０ ＊ The compensation amount C generated by the compensation unit 20 is added to the voltage phase δ by the adder 13, whereby the command value δ of the voltage phase δ is obtained. ＊ is generated.

[0091] The PWM calculation unit 12 calculates a command value K of the voltage control rate K. ＊ and the command value δ of the voltage phase δ ＊ From the above, voltage command values ​​for three phases, u, v, and w, are generated using polar coordinate transformation, inverse Park transformation, space vector transformation, etc. The three-phase voltage command values ​​are PWM (pulse width modulation) signals. The PWM calculation unit 12 calculates the amplitudes of the three-phase voltage command values ​​by multiplying the command value K of the voltage control ratio K by the voltage command value K. ＊ The PWM calculation unit 12 converts the three-phase voltage command values ​​into gate control signals G and outputs them to the inverter circuit 4.

[0092] In this way, the control unit 5A detects values ​​correlated with the motor input power harmonics, and determines at least one of the amplitude and phase of the compensation amount C based on the relationship between the motor input power harmonics and the electromagnetic excitation force harmonics that occur at the same frequencies as the motor input power harmonics. This makes it possible to reduce the motor input power harmonics and the electromagnetic excitation force harmonics.

[0093] 9, the compensator 20 superimposes the compensation amount C on the voltage phase δ, which is an example of the manipulated variable D. Alternatively, the compensator 20 superimposes the compensation amount C on the voltage phase δ, which is an example of the manipulated variable D. ａ , phase δ, amplitude I ａ and phase β.

[0094] In the example shown in FIG. 9, the reference phase calculation unit 22 calculates the reactor voltage v Ｌ The amplitude of the harmonic components generated in synchronization with the rotation speed of the motor 7 is detected by Fourier transform or the like as a value f that correlates with the motor input power harmonics generated in synchronization with the rotation speed of the motor 7. However, the reactor voltage v detected by the reference phase calculation unit 22 Ｌ The amplitude of the harmonic components generated in the DC link voltage v ｄｃ etc. may be substituted for the value f listed above.

[0095] The reference phase calculation unit 22 detects a value g that correlates with the electromagnetic vibration force harmonics that occur at the same frequency as the motor input power harmonics, and calculates a reference phase θ that minimizes the amplitude of the detected value g. ｖＬ＿ｍｉｎ Alternatively, the reference phase calculation unit 22 detects a value f that correlates with the motor input power harmonics and a value g that correlates with the electromagnetic vibration force harmonics that occur at the same frequency as the motor input power harmonics, and calculates a reference phase θ at which the amplitudes of the detected values ​​f and g become equal to or smaller than a predetermined value. ｖＬ＿ｍｉｎ may be calculated using a hill-climbing method or the like.

[0096] 10 shows an example of the results of magnetic field analysis of the motor's power and output (= torque × rotation speed) versus electrical angle. The motor 7 according to the present disclosure is an electric motor controlled by a motor control device that suppresses a first harmonic component that occurs in the input power of the motor 7 in synchronization with the rotation speed of the motor 7 or a second harmonic component that occurs in the electromagnetic excitation force of the motor 7 at the same frequency as the first harmonic component. In this motor 7, it is preferable that the magnitude p1 of the fluctuation of the frequency component that is the same as the first harmonic component in the stored energy of the motor 7 when the correction amount C is superimposed on the operation amount D is smaller than the magnitude p2 of the fluctuation of the frequency component that is the same as the second harmonic component in the output energy due to the torque of the motor 7. This results in the compensation amount C that reduces the amplitude of the harmonics of the input power of the motor 7 being similar to the compensation amount C that reduces the amplitude of the harmonics of the electromagnetic excitation force. Therefore, simply by superimposing the compensation amount C that reduces the amplitude of the harmonics of the input power of the motor 7, the amplitude of the harmonics of the electromagnetic excitation force can be reduced.

[0097] FIG. 11 is a cross-sectional view illustrating a surface permanent magnet synchronous motor 7A including a rotor 31 and a stator 32. The rotor 31 includes a rotor core 33 and a plurality of magnets 34 arranged circumferentially around the rotor core 33. The stator 32 includes a stator core 37 and coils 38. The stator core 37 includes a back yoke portion 39 and a plurality of teeth 40. The back yoke portion 39 is a substantially cylindrical portion. The back yoke portion 39 is made of a magnetic material (e.g., electromagnetic steel sheet). The plurality of teeth 40 protrude radially inward from the inner periphery of the back yoke portion 39. The teeth 40 are integral with the back yoke portion 39. The teeth 40 are made of a magnetic material (e.g., electromagnetic steel sheet). Coils 38 are wound around the plurality of teeth 40. The coils 38 are made of an insulating conductor (e.g., copper). The coils 38 are wound around each tooth 40 using a concentrated winding method. The coil 38 may be wound around a plurality of teeth 40 using a distributed winding method.

[0098] Because the inductance of the surface permanent magnet synchronous motor 7A is smaller than that of a typical interior permanent magnet synchronous motor, the energy stored in the coil 38 provided on the stator 32 of the motor 7A is smaller, and p1 shown in Fig. 10 is smaller. Therefore, the compensation amount C that reduces the amplitude of the harmonics of the input power of the motor 7A and the compensation amount C that reduces the amplitude of the harmonics of the electromagnetic excitation force are similar, so the amplitude of the harmonics of the electromagnetic excitation force can be reduced simply by superimposing the compensation amount C that reduces the amplitude of the harmonics of the input power of the motor 7A.

[0099] FIG. 12 is a cross-sectional view illustrating an interior permanent magnet synchronous motor 7B including a rotor 31 and a stator 32. The rotor 31 includes a rotor core 33 and a plurality of magnets 34 embedded in holes 35 formed in the rotor core 33. The holes 35 are slot-shaped gaps. The rotor core 33 has a magnetic resistance portion 36 arranged to interrupt the main magnetic flux generated by the magnets 34. The provision of the magnetic resistance portion 36 reduces the inductance of the motor 7B compared to a typical interior permanent magnet synchronous motor without the magnetic resistance portion 36. This reduces the energy stored in the coil 38 provided in the stator 32 of the motor 7B, thereby reducing p1 shown in FIG. 10. Therefore, the compensation amount C for reducing the amplitude of harmonics in the input power of the motor 7B is similar to the compensation amount C for reducing the amplitude of harmonics in the electromagnetic excitation force. Therefore, simply superimposing the compensation amount C for reducing the amplitude of harmonics in the input power of the motor 7B on the compensation amount C for reducing the amplitude of harmonics in the electromagnetic excitation force can reduce the amplitude of harmonics in the electromagnetic excitation force.

[0100] The magnetic resistance portion 36 is, for example, a cavity provided in the rotor core 33. Because the magnetic permeability of the air present in the cavity is lower than that of the material of the rotor core 33 (e.g., an electromagnetic steel sheet or a powder magnetic core), the magnetic resistance portion 36 obstructs the main magnetic flux of the magnet 34. Note that at least a portion of the magnetic resistance portion 36 may be replaced with a material (e.g., a non-magnetic material) having a lower magnetic permeability than the material of the rotor core 33. Even in this case, the main magnetic flux of the magnet 34 can be obstructed, just like the air present in the cavity.

[0101] FIG. 13 is a diagram illustrating an example of a refrigeration system including a motor controlled by the motor control device of the embodiment or a compressor driven by the motor of the embodiment. FIG. 13 is a diagram illustrating an example of a refrigerant circuit of an air conditioner 101 that uses a compressor 150 according to the embodiment. The air conditioner 101 is a refrigeration cycle device (refrigeration system) that includes the compressor 150. Examples of air conditioners 101 that use the compressor 150 include "air conditioners dedicated to cooling operation," "air conditioners dedicated to heating operation," "refrigeration systems dedicated to refrigeration operation," and "air conditioners that can be switched between cooling operation and heating operation using a four-way switching valve." Here, the "air conditioner that can be switched between cooling operation and heating operation using a four-way switching valve" will be used for explanation.

[0102] 13, the air conditioner 101 includes an indoor unit 102 and an outdoor unit 103, and the indoor unit 102 and the outdoor unit 103 are connected by a liquid refrigerant connection pipe 104 and a gas refrigerant connection pipe 105. As shown in Fig. 13, the air conditioner 101 is a pair type having one indoor unit 102 and one outdoor unit 103. However, the air conditioner is not limited to this, and the air conditioner 101 may also be a multi-type having a plurality of indoor units 102.

[0103] In the air conditioner 101, a refrigerant circuit 111 is formed by connecting devices such as an accumulator 115, a compressor 150, a four-way switching valve 116, an outdoor heat exchanger 117, an expansion valve 118, and an indoor heat exchanger 113 via piping.

[0104] In this embodiment, the refrigerant circuit 111 is filled with a refrigerant for operating a vapor compression refrigeration cycle. The refrigerant is a mixed refrigerant containing 1,2-difluoroethylene. The refrigerant circuit 111 is also filled with refrigerating machine oil together with the mixed refrigerant.

[0105] The indoor heat exchanger 113 mounted in the indoor unit 102 is, for example, a cross-fin type fin-and-tube heat exchanger composed of a heat transfer tube and a number of heat transfer fins. The indoor heat exchanger 113 has a liquid side connected to the liquid refrigerant connection pipe 104 and a gas side connected to the gas refrigerant connection pipe 105, and functions as a refrigerant evaporator during cooling operation.

[0106] The outdoor unit 103 is equipped with an accumulator 115 , a compressor 150 , an outdoor heat exchanger 117 , and an expansion valve 118 .

[0107] The outdoor heat exchanger 117 is, for example, a cross-fin type fin-and-tube heat exchanger configured with a heat transfer tube and a number of heat transfer fins. One end of the outdoor heat exchanger 117 is connected to the discharge pipe 124 side through which the refrigerant discharged from the compressor 150 flows, and the other end is connected to the liquid refrigerant connection pipe 104 side. The outdoor heat exchanger 117 functions as a condenser for the gas refrigerant supplied from the compressor 150 via the discharge pipe 124.

[0108] The expansion valve 118 is provided in a pipe connecting the outdoor heat exchanger 117 and the liquid refrigerant communication pipe 104. The expansion valve 118 is an electrically operated valve with an adjustable opening for adjusting the pressure and flow rate of the refrigerant flowing through the pipe.

[0109] The accumulator 115 is provided in the pipe connecting the gas refrigerant communication pipe 105 and the suction pipe 123 of the compressor 150. The accumulator 115 separates the refrigerant flowing from the indoor heat exchanger 113 through the gas refrigerant communication pipe 105 toward the suction pipe 123 into a gas phase and a liquid phase, in order to prevent liquid refrigerant from being supplied to the compressor 150. The compressor 150 is supplied with gas phase refrigerant that collects in the upper space of the accumulator 115.

[0110] <Four-way switching valve 116> Four-way switching valve 116 has first to fourth ports. In four-way switching valve 116, the first port is connected to the discharge side of compressor 150, the second port is connected to the suction side of compressor 150, the third port is connected to the gas-side end of outdoor heat exchanger 117, and the fourth port is connected to gas-side shut-off valve Vg.

[0111] The four-way selector valve 116 switches between a first state and a second state. In the first state of the four-way selector valve 116, the first port communicates with the third port and the second port communicates with the fourth port. In the second state of the four-way selector valve 116, the first port communicates with the fourth port and the second port communicates with the third port.

[0112] The compressor 150 is, for example, a scroll compressor. The compressor 150 includes a motor 170 controlled by a motor control device 160 and a compression mechanism driven by the motor 170. The compressor 150 compresses the refrigerant drawn in through a suction pipe 123 in a compression chamber by the rotational driving of the motor 170, and discharges the compressed refrigerant from a discharge pipe 124.

[0113] The motor control device 160 controls the motor 170 using AC power supplied from an AC power supply. The motor control device 160 corresponds to the motor control devices 1A, 1B, etc. in the above embodiments. The motor 170 corresponds to the motor 7, etc. controlled by the motor control devices 1A, 1B, etc. in the above embodiments or the motor 7A, 7B, etc. in the above embodiments. Therefore, an air conditioner 101 is provided that includes a compressor 150 equipped with a motor 170 that is capable of reducing harmonic components generated in the input power of the motor 170 and harmonic components generated in the electromagnetic excitation force of the motor 170.

[0114] The refrigeration device is not limited to an air conditioner, but may be an oil-cooled device or the like.

[0115] 14 is a diagram showing an example of a motor controlled by the motor control device of the embodiment or a vehicle equipped with the motor of the embodiment. The motor 180 transmits driving force to a drive shaft that drives the drive wheels of the vehicle 400. The vehicle 400 may be an EV (electric vehicle) powered only by the motor 180, or may be an HV (hybrid vehicle) or PHEV (plug-in hybrid electric vehicle) powered by both the motor 180 and an internal combustion engine or the like.

[0116] The vehicle 400 includes a motor control device 190 and a motor 180 controlled by the motor control device 190. Note that the mounting positions of the motor control device 190 and the motor 180 shown in the figure are shown for convenience and are not limited to the positions shown in the figure.

[0117] The motor control device 190 controls the motor 180 using DC power supplied from a DC power source such as an on-board battery. The motor control device 190 corresponds to the motor control devices 1A, 1B, etc. in the above embodiments. The motor 180 corresponds to the motor 7, etc. controlled by the motor control devices 1A, 1B, etc. in the above embodiments or the motor 7A, 7B, etc. in the above embodiments. Therefore, a vehicle 400 is provided that is equipped with a motor 180 that is capable of reducing harmonic components generated in the input power of the motor 180 and harmonic components generated in the electromagnetic excitation force of the motor 180.

[0118] Although the embodiments have been described above, it will be understood that various changes in form and details are possible without departing from the spirit and scope of the claims. Various modifications and improvements, such as combinations and substitutions with part or all of other embodiments, are possible.

[0119] This international application claims priority based on Japanese Patent Application No. 2021-059252, filed on March 31, 2021, and the entire contents of Japanese Patent Application No. 2021-059252 are incorporated herein by reference.

[0120] REFERENCE SIGNS LIST 1A, 1B Motor control device 4 Inverter circuit 5, 5A Control unit 6 AC power supply 7, 7A, 7B Motor 8 Reactor 20 Compensation unit 101 Air conditioner 111 Refrigerant circuit 150 Compressor 160, 190 Motor control device 170, 180 Motor 400 Vehicle

Claims

DEPCT671. A motor control unit configured to convert the input power supplied from a power source into an output AC power of a predetermined voltage and frequency, in which the motor control unit shall consist of: an inversion circuit configured to supply the output AC power to the motor, in which the motor control unit shall perform control to suppress the amplitude of the first harmonic component, which arises in sync with the motor's rotational speed under the applied power condition, to a predetermined value, and to suppress the amplitude of the second harmonic component, which arises in the motor's electromagnetic interference at the same frequency as the first harmonic component, to a value lower than the amplitude of the second harmonic component, where the amplitude of the first harmonic component is suppressed to a minimum.

2. A motor control unit according to claim 1, where the power source is an AC power source.3.A motor control unit under claim 1 or 2 where the frequency of the first and second harmonic components is the frequency which is the product of the fundamental frequency of the voltage supplied to the motor and is a product of 64. Any one of the motor control units under claim 1 to 3 shall also include: a control unit configured to perform control such that the control unit superimposes a compensation quantity that changes in sync with the motor rotation rate onto the operating quantity of the motor control unit.

5. A motor control unit under claim 4 where the operating quantity shall be at least one of the following, chosen from the modulation ratio of the inverse circuit, the amplitude of the voltage vector of the voltage supplied to the motor, the phase of the voltage vector, the amplitude of the current vector of the current supplied to the motor, and the phase of the current vector. 6.

7. A motor control unit under claim 4 or 5 where the control unit detects values ​​that correlate with the first harmonic component and determines the amplitude and phase of one or both compensation quantities based on the relationship between the first and second harmonic components.

8. A motor control unit under claim 6 or 7 where the motor control unit maintains the relationship in the form of a table or formula.

9. A motor control unit under claim 4 or 5 where the control unit detects values ​​that correlate with the first harmonic component and values ​​that correlate with the second harmonic component and determines the amplitude and phase of one or both compensation quantities based on the relationship between the first and second harmonic components.A motor control unit under claim 4 or 5 where the control unit determines the amplitude and phase of one or both compensation quantities based on a preserved table or formula.

11. A motor control unit under any of claims 1 through 10 where, when control is performed, the magnitude of the variation of the power component stored in the motor at the same frequency as the first harmonic component is less than the magnitude of the variation of the power component output through the motor torque at the same frequency as the second harmonic component.12.A motor controlled by a motor controller configured to suppress the first harmonic component, which arises in sync with the motor's rotational speed under the power supplied to the motor, or the second harmonic component, which arises in the motor's electromagnetic disturbance at the same frequency as the first harmonic component, such that when suppression is performed in the motor, the magnitude of the variation in the power component stored in the motor at the same frequency as the first harmonic component is less than the magnitude of the variation in the power component output through the motor's torque at the same frequency as the second harmonic component.

13. A motor under claim12 where the motor is a surface magneto-coupled motor consisting of a rotor and a stator, and the rotor consists of a rotor shaft and several magnets arranged in a direction along the circumference of the rotor shaft.14.A motor under claim 12 where the motor is a magnetically coupled type motor consisting of a rotor and a stator; the rotor consists of a rotor shaft and several magnets which are embedded in holes made in the rotor shaft; and the rotor shaft contains a magnetic resistance section which is provided to suppress the primary magnetic flux of the magnets.

15. A compressor driven by a motor which is controlled by any motor control unit under claims 1 to 11 or by any motor under claims 12 to 14.

16. A refrigeration unit which includes: a compressor under claim 15.

17. A vehicle fitted with a motor which is controlled by any motor control unit under claims 1 to 11 or with any motor under claims 12 to 14.

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