Control device for an alternating current rotating electric machine

Abstract

The present application provides a kind of control device of alternating current rotating electrical machine, when switching from full-phase short-circuit state to switch control, the control precision of current can be inhibited to deteriorate.Control device (1) of alternating current rotating electrical machine is based on current command value and the detection value of current to calculate voltage command value, based on voltage command value, switch control to the multiple switch elements that inverter has is carried out to switch on and off, and full-phase short-circuit control to the multiple switch elements is carried out to switch on and off to make multiple-phase winding mutual short circuit, when switching from full-phase short-circuit control to switch control, current command value is set to the value that is equivalent to the current that full-phase short-circuit control is carried out, i.e.switching current value.

Description

TECHNICAL FIELD

[0001] The present application relates to a control device of an alternating-current rotary electric machine. BACKGROUND

[0002] In a control device of an alternating-current rotary electric machine (hereinafter, also referred to as a motor), a sensorless system in which a motor is driven without using a position sensor of a rotor is widely popular. In the control device of the alternating-current rotary electric machine of the sensorless system as described above, a structure in which an inverter is restarted from a state in which the rotor is idling in a state in which the inverter is stopped is disclosed.

[0003] In the technology of Patent Literature 1, the winding is short-circuited for a certain time when the motor is idling, and the position and the speed of the rotor estimated based on the winding current at that time and the time until the restart are used to initialize the estimated value of the position, and the inverter is restarted.

[0004] In the technology of Patent Literature 2, the winding is short-circuited when the motor is idling, and the position of the rotor estimated based on the winding current at that time is used to initialize the estimated value of the position, and the inverter is restarted.

[0005] Further, in the technology of Patent Literature 3, a sensorless control device of an alternating-current motor in which high-speed and high-precision speed control can be performed by performing current feedback control and feedforward control is disclosed.

[0006] PRIOR ART DOCUMENTS

[0007] PATENT LITERATURE

[0008] Patent Literature 1: Japanese Patent Laid-Open No. 11-75394

[0009] Patent Literature 2: Japanese Patent Laid-Open No. 2018-7390

[0010] Patent Literature 3: Japanese Patent Laid-Open No. 2010-279095

[0011] Patent Literature 4: Japanese Patent No. 4672236

[0012] Patent Literature 5: Japanese Patent No. 6253850 SUMMARY

[0013] PROBLEMS TO BE SOLVED BY THE INVENTION

[0014] However, in the technology of Patent Literature 1, the inverter is stopped again after the winding is short-circuited once, and thus, in a system in which the induced voltage of the motor exceeds the power supply voltage, unintended regenerative current flows. Therefore, if applied to a system in which, for example, the motor is connected to an engine in a car, and a battery is used as a power supply, overcharging of the battery can occur.

[0015] Further, in the technology of Patent Literature 2, the inverter is restarted from the short-circuit state, and thus the estimation itself can be performed. However, when the inverter is restarted, the influence of the current flowing in the short-circuit state is not taken into account, and thus the control accuracy of the current deteriorates immediately after the restart, and the estimation accuracy can deteriorate.

[0016] Similarly, in Patent Literature 3, the case where the inverter is restarted from the three-phase short-circuit state is not taken into account.

[0017] Therefore, in the case where the technologies of these Patent Literatures are combined, since the influence of the current flowing in the three-phase short-circuit state is not taken into account, the control accuracy of the current deteriorates immediately after the restart from the three-phase short-circuit state, and torque fluctuation can occur. Further, in the case where sensorless control is performed, since the control accuracy of the current deteriorates, the estimation accuracy of the rotational angle and the rotational angular velocity deteriorates, and torque fluctuation can occur.

[0018] Therefore, an object of the present application is to provide a control device of an alternating-current rotary electric machine that can suppress deterioration of the control accuracy of a current when switching from full-phase short-circuit control in which a plurality of windings are short-circuited to each other to switching control in which a switching element is turned on and off based on a voltage command value.

[0019] Technical means for solving the technical problem

[0020] A control device of an alternating-current rotary electric machine according to the present application, which controls an alternating-current rotary electric machine having a stator and a rotor provided with a plurality of windings via an inverter, includes:

[0021] a current detection section that detects a current flowing through the plurality of windings;

[0022] a current command value calculation section that sets a current command value;

[0023] a voltage command value calculation section that calculates a voltage command value based on the current command value and a detected value of the current; and

[0024] an inverter control section that switchingly performs, based on the voltage command value, switching control of turning on and off a plurality of switching elements possessed by the inverter to apply a voltage to the plurality of windings, and full-phase short-circuit control of turning on and off the plurality of switching elements to short-circuit the plurality of windings to each other,

[0025] when switching from the full-phase short-circuit control to the switching control, the current command value calculation section sets the current command value to a switching current value that corresponds to the current flowing when the full-phase short-circuit control is performed.

[0026] Effects of the Invention

[0027] According to the control device for an AC rotating electric machine disclosed in this application, when switching from full-phase short-circuit control to switching control, the current command value is set to a switching current value, equivalent to the current flowing during full-phase short-circuit control. This reduces the deviation between the current immediately after full-phase short-circuit control and the current command value during switching control. Consequently, the current deviation between the current command value and the current detection value can be reduced during switching, preventing a transient increase in the manipulated variable and a significant fluctuation in the current value, thereby suppressing transient torque fluctuations. BRIEF DESCRIPTION OF THE DRAWINGS

[0028] Figure 1 This is a schematic configuration diagram of an AC rotating electric machine and a control device for the AC rotating electric machine according to the first embodiment.

[0029] Figure 2 This is a schematic block diagram of a control device for an AC rotating electric machine according to the first embodiment.

[0030] Figure 3 This is a hardware configuration diagram of the control device for the AC rotating electric machine according to the first embodiment.

[0031] Figure 4 This is a block diagram of a current command value calculation unit according to the first embodiment.

[0032] Figure 5 This is a flowchart for explaining the processing during handover according to the first embodiment.

[0033] Figure 6 It is a timing chart showing a control operation according to a comparative example.

[0034] Figure 7 This is a timing chart showing the control operation according to the first embodiment.

[0035] Figure 8 This is a block diagram of a current command value calculation unit according to the second embodiment.

[0036] Figure 9 This is a flowchart for explaining the processing during switching involved in the second embodiment.

[0037] Figure 10 This is a timing chart showing the control operation according to the second embodiment.

[0038] Figure 11 This is a diagram illustrating the effects of the second embodiment.

[0039] Figure 12 This is a block diagram of a current command value calculation unit according to the third embodiment. DETAILED DESCRIPTION

[0040] 1. Embodiment 1

[0041] A control device 1 (hereinafter simply referred to as control device 1) for an alternating-current rotary electric machine according to Embodiment 1 will be described with reference to the drawings. Figure 1 is a schematic configuration diagram of an alternating-current rotary electric machine 2 and the control device 1 according to the present embodiment.

[0042] 1-1. Alternating-current rotary electric machine

[0043] The alternating-current rotary electric machine 2 has a stator and a rotor provided with a multiphase winding. In the present embodiment, three-phase windings Cu, Cv, Cw of U phase, V phase, and W phase are provided. The three-phase windings Cu, Cv, Cw are star-connected. Alternatively, the three-phase windings can be delta-connected. The alternating-current rotary electric machine 2 is configured as a permanent magnet synchronous rotary electric machine, and a permanent magnet is provided on the rotor.

[0044] 1-2. Inverter and the like

[0045] The inverter 20 is a power converter that performs power conversion between the direct-current power supply 10 and the three-phase winding, and has a plurality of switching elements. The inverter 20 is provided with three sets of series circuits (legs) corresponding to the windings of the three phases, and the series circuits are connected in series with the positive-side switching elements 23H (upper arms) connected to the positive side of the direct-current power supply 10 and the negative-side switching elements 23L (lower arms) connected to the negative side of the direct-current power supply 10. The inverter 20 includes three positive-side switching elements 23H and three negative-side switching elements 23L, for a total of six switching elements. Furthermore, the connection points at which the positive-side switching elements 23H and the negative-side switching elements 23L are connected in series are connected to the windings of the corresponding phases.

[0046] Specifically, in the series circuit of each phase, the collector terminal of the positive-side switching element 23H is connected to the positive-side wire 14, the emitter terminal of the positive-side switching element 23H is connected to the collector terminal of the negative-side switching element 23L, and the emitter terminal of the negative-side switching element 23L is connected to the negative-side wire 15. The connection point between the positive-side switching element 23H and the negative-side switching element 23L is connected to the winding of the corresponding phase. For the switching elements, an IGBT (Insulated Gate Bipolar Transistor) with a diode 22 connected in antiparallel, or a MOSFET (Metal Oxide Semiconductor Field Effect Transistor) with the function of an antiparallel diode is used. The gate terminal of each switching element is connected to the control device 1. Each switching element is turned on or off by a control signal output from the control device 1.

[0047] The filter capacitor 12 is connected between the positive-side wire 14 and the negative-side wire 15. A power supply voltage sensor 13 is provided to detect the power supply voltage supplied from the DC power supply 10 to the inverter 20. The power supply voltage sensor 13 is connected between the positive-side wire 14 and the negative-side wire 15. The output signal of the power supply voltage sensor 13 is input to the control device 1.

[0048] Current sensor 17 outputs an electrical signal corresponding to the current flowing through each phase winding. Current sensor 17 is provided on the wires of each phase connecting the series circuit of the switching elements to the windings. The output signal of current sensor 17 is input to control device 1. Alternatively, current sensor 17 may be provided in the series circuit of each phase.

[0049] A rechargeable power storage device (eg, a lithium-ion battery, a nickel-metal hydride battery, or an electric double-layer capacitor) is used as the DC power supply 10. The DC power supply 10 may also include a DC-DC converter that steps up or down a DC voltage.

[0050] 1-3. Control device

[0051] The control device 1 controls the AC rotating electric machine 2 via the inverter 20. Figure 2 As shown in FIG. 1 , the control device 1 includes a voltage detection unit 31, a current detection unit 32, a current command value calculation unit 33, a voltage command value calculation unit 34, an inverter control unit 35, a rotation detection unit 36, and a switching control unit 37, which will be described later. Each function of the control device 1 is realized by a processing circuit provided by the control device 1. Specifically, the control device 1 is as follows. Figure 3As shown, as a processing circuit, it has an operation processing device 90 (computer) such as a CPU (Central Processing Unit), a storage device 91 for exchanging data with the operation processing device 90, an input circuit 92 for inputting external signals to the operation processing device 90, and an output circuit 93 for outputting signals from the operation processing device 90 to the outside.

[0052] The processing device 90 may include an ASIC (Application Specific Integrated Circuit), an IC (Integrated Circuit), a DSP (Digital Signal Processor), an FPGA (Field Programmable Gate Array), various logic circuits, and various signal processing circuits. Furthermore, the processing device 90 may include multiple processing devices of the same or different types to share the execution of various processes. The storage device 91 may include a RAM (Random Access Memory) configured to read and write data from the processing device 90, or a ROM (Read Only Memory) configured to read data from the processing device 90. The input circuit 92 is connected to various sensors and switches, such as the power supply voltage sensor 13 and the current sensor 17, and includes an A / D converter, etc., that inputs the output signals of these sensors and switches to the processing device 90. The output circuit 93 is connected to electrical loads, such as gate drive circuits that drive switching elements on and off, and includes a drive circuit, etc., that outputs control signals from the processing device 90 to these electrical loads.

[0053] Furthermore, the control device 1 has Figure 2 The functions of the control units 31 to 37 are realized by the arithmetic processing unit 90 executing software (programs) stored in a storage device 91, such as a ROM, in cooperation with other hardware components of the control device 1, such as the storage device 91, the input circuit 92, and the output circuit 93. Furthermore, the setting data used by the control units 31 to 37 is stored in the storage device 91, such as the ROM, as part of the software (programs). The functions of the control device 1 are described in detail below.

[0054] 1-3-1. Voltage Detection Unit 31

[0055] The voltage detection unit 31 detects the power supply voltage VDC supplied from the DC power supply 10 to the inverter 20. In the present embodiment, the voltage detection unit 31 detects the power supply voltage VDC based on the output signal of the power supply voltage sensor 13.

[0056] 1-3-2. Current detection section 32

[0057] The current detection section 32 detects currents Iur, Ivr, and Iwr flowing through the three-phase windings. In the present embodiment, the current detection section 32 detects the currents Iur, Ivr, Iwr flowing through the respective phase windings Cu, Cv, Cw from the inverter 20 based on the output signals of the current sensors 17. Here, Iur is the U-phase current detection value, Ivr is the V-phase current detection value, and Iwr is the W-phase current detection value. In addition, the current sensors 17 are configured to detect the winding currents of two phases, and the winding current of the remaining one phase can also be calculated based on the detection values of the winding currents of the two phases. For example, the current sensors 17 detect the winding currents Ivr and Iwr of the V-phase and W-phase, and the winding current Iur of the U-phase can be calculated by Iur = -Ivr - Iwr.

[0058] The current detection section 32 converts the three-phase current detection values Iur, Ivr, Iwr into a d-axis current detection value Idr and a q-axis current detection value Iqr in a rotating coordinate system of the d-axis and q-axis. The rotating coordinate system of the d-axis and q-axis is a 2-axis rotating coordinate constituted by a d-axis determined in the direction of the detected magnetic pole position θ and a q-axis determined in the direction that advances 90° in the electrical angle from the d-axis, and rotates in synchronization with the rotation of the magnetic pole position of the rotor. Specifically, the current detection section 32 performs three-phase to two-phase conversion and rotating coordinate conversion on the three-phase current detection values Iur, Ivr, Iwr based on the magnetic pole position θ, and converts into the d-axis current detection value Idr and the q-axis current detection value Iqr.

[0059] 1-3-3. Voltage command value calculation section 34

[0060] The voltage command value calculation section 34 calculates the voltage command values based on the current command values and the detection values of the currents. In the present embodiment, the voltage command value calculation section 34 calculates the voltage command values Vuo, Vvo, Vwo of the three phases as the voltage command values.

[0061] The voltage command value calculation section 34 performs current feedback control that changes the d-axis voltage command value Vdo and the q-axis voltage command value Vqo by PI control or the like, so that the d-axis current detection value Idr approaches the d-axis current command value Ido and the q-axis current detection value Iqr approaches the q-axis current command value Iqo. In addition, feedforward control can also be performed to make the d-axis current and the q-axis current less susceptible to disturbances or the like.

[0062] For example, the voltage command value calculation section 34 performs the operation shown in the following equation to calculate the d-axis and q-axis voltage command values Vdo, Vqo. In Equation (1), feedback control and feedforward control are performed.

[0063] [Math. 1]

[0064]

[0065] Here, R is winding resistance, Ld is inductance of the d-axis, Lq is inductance of the q-axis, ω is rotational angular velocity, Ψp is the flux linkage of the permanent magnet, ωcc is the response angular frequency of the target of current control, and s is the Laplace operator.

[0066] The voltage command value calculation section 34 performs fixed coordinate conversion and two-phase / three-phase conversion on the voltage command values Vdo, Vqo of the d-axis and the q-axis based on the magnetic pole position θ, and converts them into three-phase voltage command values Vuo, Vvo, Vwo. In addition, a zero-phase component such as a 3rd harmonic can be added to the three-phase voltage command values.

[0067] 1-3-4. Inverter control section 35

[0068] The inverter control section 35 performs switching control of switching the multiple switching elements possessed by the inverter on and off to apply a voltage to the three-phase winding, and all-phase short-circuit control of making the multiple switching elements on and off so that the three-phase winding is short-circuited to each other, based on the voltage command values, using PWM (Pulse Width Modulation) control.

[0069] In the present embodiment, the inverter control section 35 includes a switching control section 35a, an all-phase short-circuit control section 35b, and an output switching section 35c.

[0070] The switching control section 35a controls the multiple switching elements on and off using PWM based on the three-phase voltage command values Vuo, Vvo, Vwo. The switching control section 35a compares the three-phase voltage command values with a carrier wave respectively, thereby generating switching signals that turn the switching elements of each phase on and off. The carrier wave is set to a triangular wave that vibrates with an amplitude of the power supply voltage VDC / 2 centered on 0 in a carrier frequency. The switching control section 35a turns the switching signal on when the voltage command value exceeds the carrier wave, and turns the switching signal off when the voltage command value is less than the carrier wave. The switching signal is directly transmitted to the switching element on the positive side, and the switching signal obtained by inverting the switching signal is transmitted to the switching element on the negative side.

[0071] The all-phase short-circuit control section 35b generates each switching signal that turns the switching elements on the positive side of the three-phase all phases on and turns the switching elements on the negative side of the three-phase all phases off, or generates each switching signal that turns the switching elements on the positive side of the three-phase all phases off and turns the switching elements on the negative side of the three-phase all phases on. Thereby, the terminals of the three-phase winding are short-circuited to each other.

[0072] In a case where it is determined that switching control by the switching control section 37 described later is performed (switching signal STAT = 1), the output switching section 35c inputs each of the switching signals of the switching control section 35a to the gate terminal of each of the switching elements of the inverter 20 via the gate drive circuit to cause each of the switching elements to be turned on or off. In a case where it is determined that full-phase short-circuit control by the full-phase short-circuit control section 35b is performed (switching signal STAT = 0), the output switching section 35c inputs each of the switching signals of the full-phase short-circuit control section 35b to the gate terminal of each of the switching elements of the inverter 20 via the gate drive circuit to cause each of the switching elements to be turned on or off.

[0073] 1) STAT = 1: output the signals of the switching control section 35a to the inverter

[0074] 2) STAT = 0: output the signals of the full-phase short-circuit control section 35b to the inverter

[0075] 1-3-5. Current command value calculation section 33

[0076] The current command value calculation section 33 calculates a current command value. In the present embodiment, the current command value calculation section 33 calculates a current command value Id0 on the d-axis and a current command value Iq0 on the q-axis as the current command value.

[0077] As shown in Figure 4 , the current command value calculation section 33 calculates a target value Mo of a modulation factor. In the present embodiment, the target value Mo of the modulation factor is set to a constant value (for example, 1.21). In addition, the target value Mo of the modulation factor can vary based on the operation state such as the torque command value To and the rotational angular velocity ω. The modulation factor is a ratio of the amplitude of the fundamental wave component of the applied voltage of the three-phase winding with respect to the power supply voltage VDC / 2.

[0078] The current command value calculation section 33 calculates a flux linkage command value Ψ0 based on the target value Mo of the modulation factor. The flux linkage command value Ψ0 is a command value of the armature flux linkage. The current command value calculation section 33 multiplies the power supply voltage VDC by the target value Mo of the modulation factor and divides the result by the rotational angular velocity ω to calculate the flux linkage command value Ψ0. In detail, as shown in Figure 4 and the following equation, the current command value calculation section 33 multiplies 1 / 2 x √(3 / 2) by the power supply voltage VDC and the target value Mo of the modulation factor and divides the result by the rotational angular velocity ω to calculate the flux linkage command value Ψ0.

[0079] [Equation 2]

[0080]

[0081] In addition, the flux linkage command value Ψ0may be corrected by feedback control so that the difference between the target value Mo of the modulation rate and the actual modulation rate Mr becomes small. The actual modulation rate Mr is calculated, for example, based on the dq-axis voltage command values Vdo, Vqo.

[0082] The current command value calculating section 33 calculates the normal d-axis current command value IdoD and the normal q-axis current command value IqoD based on the flux linkage command value Ψ0and the torque command value To. The current command value calculating section 33 refers to the d-axis current setting data in which the relationship between the flux linkage command value Ψ0and the torque command value To and the d-axis current command value IdoD is set in advance, and calculates the normal d-axis current command value IdoD corresponding to the calculated flux linkage command value Ψ0and torque command value To. The current command value calculating section 33 refers to the q-axis current setting data in which the relationship between the flux linkage command value Ψ0and the torque command value To and the q-axis current command value IqoD is set in advance, and calculates the normal q-axis current command value IqoD corresponding to the calculated flux linkage command value Ψ0and torque command value To.

[0083] In addition, the torque command value To can be calculated within the control device 1 or can be transmitted from an external device.

[0084] <Setting of current command value at switching>

[0085] When switching from the full-phase short-circuit control to the switching control, the difference between the current value at the time of execution of the full-phase short-circuit control and the current command value of the switching control is large, and therefore the operation amount becomes excessively large in transition, and torque fluctuation can occur. Therefore, when switching from the full-phase short-circuit control to the switching control, it is desirable that torque fluctuation not occur in transition due to the current difference becoming large.

[0086] Therefore, when switching from the full-phase short-circuit control to the switching control, the current command value calculating section 33 sets the current command values to values corresponding to the current flowing at the time of execution of the full-phase short-circuit control, that is, switching current values. In the present embodiment, when switching from the full-phase short-circuit control to the switching control, the current command value calculating section 33 sets the d-axis and q-axis current command values Ido, Iqo to the d-axis switching current value IdPS and the q-axis switching current value IqPS, which are values corresponding to the current flowing at the time of execution of the full-phase short-circuit control.

[0087] According to this structure, when switching from the full-phase short-circuit control to the switching control, the difference between the current value at the time of execution of the full-phase short-circuit control and the current command value of the switching control can be made small. Therefore, the current difference between the current command value and the current detection value at the time of switching can be made small, and the situation in which the operation amount becomes excessively large in transition and the current value greatly fluctuates can be suppressed, and torque fluctuation can be suppressed from occurring in transition.

[0088] Setting of switching current values

[0089] The current values of the d-axis and the q-axis at the time of execution of the full-phase short-circuit control are derived. The voltage equation on the rotating coordinate system of the d-axis and the q-axis becomes equation (3).

[0090] [Math. 3]

[0091]

[0092] In the full-phase short-circuit control, the three-phase winding is short-circuited, and the voltage is not applied to the three-phase winding, and therefore, in equation (3), the d-axis voltage Vd = 0 and the q-axis voltage Vq = 0 are set. Further, assuming that it is in a steady state, the differential value of the d-axis current dId / dt = 0 and the differential value of the q-axis current dIq / dt = 0 are set. Therefore, if the simultaneous equations are solved with respect to the d-axis current Id and the q-axis current Iq, equation (4) is obtained. The d-axis current Id and the q-axis current Iq of equation (4) can be set to values equivalent to the currents flowing at the time of execution of the full-phase short-circuit control, that is, the switching current value of the d-axis IdPS and the switching current value of the q-axis IqPS.

[0093] [Math. 4]

[0094]

[0095] Therefore, in the present embodiment, the current command value calculation section 33 sets the switching current value of the d-axis IdPS and the switching current value of the q-axis IqPS based on the rotational angular velocity ω using equation (4). The d-axis inductance Ld, the q-axis inductance Lq, the magnet linkage flux Ψp, and the winding resistance value R of equation (4) use values set in advance. Instead of equation (4), setting data of the d-axis switching value in which the relationship between the rotational angular velocity ω and the switching current value of the d-axis IdPS is set in advance, and setting data of the q-axis switching value in which the relationship between the rotational angular velocity ω and the switching current value of the q-axis IqPS is set in advance can be used.

[0096] At the time of switching from the full-phase short-circuit control to the switching control, the current command value calculation section 33 sets the current command values Ido, Iqo of the d-axis and the q-axis to the switching current values IdPS, IqPS of the d-axis and the q-axis, and thereafter causes the current command values Ido, Iqo of the d-axis and the q-axis to gradually change from the switching current values IdPS, IqPS of the d-axis and the q-axis to the normal current command values IdoD, IqoD of the d-axis and the q-axis normally set in the switching control.

[0097] According to this structure, it is possible to suppress the deviation between the current detection value and the current command value of the switching control from becoming large, to suppress the occurrence of a torque variation transiently, and to smoothly switch to the switching control using the normal current command value.

[0098] When switching from the full-phase short-circuit control to the switching control, the current command value calculating section 33 sets the d-axis and q-axis current command values Id0, Iq0 to the d-axis and q-axis switching current values IdPS, IqPS, and after the standby time Tdly, gradually changes the d-axis and q-axis current command values Id0, Iq0 from the d-axis and q-axis switching current values IdPS, IqPS to the normal d-axis and q-axis current command values Id0D, Iq0D normally set in the switching control.

[0099] According to this structure, the current command value is set to the switching current value, and the standby time Tdly is set after the switching control is started, so the gradual change of the current command value can be started after the control values are stabilized, and the switching to the switching control using the normal current command value can be more stably performed.

[0100] The standby time Tdly can be set in correspondence with the period until the current is stabilized to the switching current value after the switching to the switching control.

[0101] 1-3-6. Rotation detecting section 36

[0102] The rotation detecting section 36 detects the rotation angle θ of the rotor (the magnetic pole position θ of the rotor) and the rotation angular velocity ω at the electrical angle. In the present embodiment, the rotation detecting section 36 estimates the rotation angle θ and the rotation angular velocity ω based on the current detection value. The rotation detecting section 36 switches the estimation method at the time of execution of the full-phase short-circuit control and at the time of execution of the switching control.

[0103] As shown in Figure 2 , the rotation detecting section 36 includes an estimation section 36a at the time of full-phase short-circuit, an estimation section 36b at the time of switching control, and an estimation value switching section 36c.

[0104] <Estimation at the time of full-phase short-circuit>

[0105] The estimation section 36a at the time of full-phase short-circuit estimates the 1st rotation angle θ1 and the 1st rotation angular velocity ω1 using the same estimation method as in Patent Literature 1 using the following formula at the time of execution of the full-phase short-circuit control.

[0106] [Formula 5]

[0107]

[0108]

[0109] For the first term on the right side of the first equation of formula (5), the estimation unit 36a at the time of the three-phase short-circuit performs three-phase two-phase conversion on the three-phase current detection values Iur, Ivr, Iwr to calculate the current value Ia of the a-axis and the current value Iβ of the β-axis. For the second term on the right side of the first equation of formula (5), Iq / Id is calculated by a table data or a function with the first rotational angular velocity ωl as an input. In addition, in a PLL (Phase Locked Loop) constituted by software, θl can be used as an input, and a value of an output of a controller input to an integrator can be set as ωl.

[0110] In particular, if it is assumed that the resistance value R of the winding is sufficiently small with respect to the impedance of the inductance of the winding, and R = 0 is set in formula (4), the current value Id of the d-axis and the current value Iq of the q-axis at the time of the three-phase short-circuit are represented by the following formula, the current vector is located near the d-axis on the negative side, and the phase of the current vector becomes -π.

[0111] [mathematical formula 6]

[0112]

[0113] Thus, the first rotational angle θl can be simply estimated by the following formula obtained by substituting -π into the second term on the right side of the first equation of formula (5). In this case, the table data described above is not necessary.

[0114] [mathematical formula 7]

[0115]

[0116] The estimation by the estimation unit 36a at the time of the three-phase short-circuit does not require the condition that the estimated value is near the true value, and thus even in the case where the rotational angular velocity of the motor is excessively large and becomes a three-phase short-circuit due to a fail-safe, the estimation of the angle can be performed more stably than the estimation unit 36b at the time of the switching control described later.

[0117] <Estimation at the time of switching control>

[0118] The estimation unit 36b at the time of the switching control estimates the second rotational angle θ2 and the second rotational angular velocity ω2 using a publicly known estimation method (for example, Patent Literature 4) at the time of execution of the switching control. For example, in the angle estimation using an adaptive observer, the current detection values Idr, Iqr of the d-axis and the q-axis and the voltage command values Vdo, Vqo of the d-axis and the q-axis are input to the adaptive observer, and the second rotational angle θ2 and the second rotational angular velocity ω2 are output from the adaptive observer. The estimation method is a publicly known technique, and thus a detailed description is omitted.

[0119] When switching from all-phase short-circuit control to switching control, the estimating unit 36 ​​b during switching control sets the first rotation angle θ1 and first rotation angular velocity ω1 estimated immediately before switching as initial values ​​of the second rotation angle θ2 and second rotation angular velocity ω2.

[0120] <Estimated Value Switching Unit 36c>

[0121] When the switching control unit 37 determines that switching control is to be executed (switching signal STAT = 1), the estimated value switching unit 36c outputs the second rotation angle θ2 and the second rotation angular velocity ω2 estimated by the estimating unit 36b during switching control as the final rotation angle θ and the rotation angular velocity ω. On the other hand, when the switching control unit 37 determines that all-phase short-circuit control is to be executed (switching signal STAT = 0), the estimated value switching unit 36c outputs the first rotation angle θ1 and the first rotation angular velocity ω1 estimated by the estimating unit 36a during all-phase short-circuit control as the final rotation angle θ and the rotation angular velocity ω.

[0122] 1) When STAT=1: θ=θ2, ω=ω2

[0123] 2) When STAT=0: θ=θ1, ω=ω1

[0124] 1-3-7. Switching Control Unit 37

[0125] The switching control unit 37 switches between switching control and full-phase short-circuit control. When executing switching control, the switching control unit 37 sets the switching signal STAT to 1, and when executing full-phase short-circuit control, the switching control unit 37 sets the switching signal STAT to 0. The switching control unit 37 switches based on instructions for executing switching control or full-phase short-circuit control transmitted from a higher-level control unit (not shown) or an external control device. For example, when the AC rotating electric machine 2 stops operating, an instruction to execute full-phase short-circuit control is issued.

[0126] 1) When the switch control is executed: STAT=1

[0127] 2) When executing full-phase short-circuit control: STAT=0

[0128] 1-3-8. Flowchart for switching

[0129] For the processing of the control device involving the switching of the full-phase short-circuit control and the switch control described above, use Figure 5 The flowchart is used to illustrate. Figure 5 The processing is performed, for example, in each predetermined operation cycle.

[0130] In step S01, the switching control section 37 determines which of the execution instruction of the full-phase short-circuit control and the execution instruction of the switching control is transmitted, and in the case where the execution instruction of the switching control is transmitted, proceeds to step S02, and in the case where the execution instruction of the full-phase short-circuit control is transmitted, proceeds to step S03.

[0131] In step S02, the switching control section 37 sets the switching signal STAT = 1, causes the current command value calculation section 33, the voltage command value calculation section 34, the inverter control section 35, and the like to execute the switching control, and causes the rotation detection section 36 to perform the estimation of the rotational angle and the rotational angular velocity at the time of the switching control.

[0132] On the other hand, in step S03, the switching control section 37 sets the switching signal STAT = 0, causes the inverter control section 35 to execute the full-phase short-circuit control, and causes the rotation detection section 36 to perform the estimation of the rotational angle and the rotational angular velocity at the time of the full-phase short-circuit.

[0133] In step S04, the current command value calculation section 33 determines whether or not it is the time when the switching signal STAT changes from 0 to 1, and in the case where it is the change time, proceeds to step S05, and in the case where it is not the change time, proceeds to step S07. In step S05, the rotation detection section 36 sets the first rotational angle θ1 and the first rotational angular velocity ω1 estimated immediately before the switching at the time of the full-phase short-circuit as initial values of the second rotational angle θ2 and the second rotational angular velocity ω2 at the time of the switching control.

[0134] Further, in step S06, the current command value calculation section 33 sets the current command values Id0, Iq0 of the d-axis and the q-axis to the switching current values IdPS, IqPS of the d-axis and the q-axis. In addition, in the case where the primary delay filter processing is performed in the process of calculating the current command values Id0, Iq0 of the d-axis and the q-axis, the current command value calculation section 33 can set the current command values Id0, Iq0 of the d-axis and the q-axis to the switching current values IdPS, IqPS of the d-axis and the q-axis in the execution of the full-phase short-circuit control so that the current command values Id0, Iq0 of the d-axis and the q-axis become the switching current values IdPS, IqPS of the d-axis and the q-axis when the switching from the full-phase short-circuit control to the switching control (the time when the switching signal STAT changes from 0 to 1). Alternatively, the current command value calculation section 33 can reset the internal operation values such as the last operation values of the primary delay filter processing to the switching current values IdPS, IqPS of the d-axis and the q-axis so that the current command values Id0, Iq0 of the d-axis and the q-axis become the switching current values IdPS, IqPS of the d-axis and the q-axis when the switching from the full-phase short-circuit control to the switching control (the time when the switching signal STAT changes from 0 to 1).

[0135] In step S07, the current command value calculation portion 33 determines whether the standby time Tdly has elapsed after the switching signal STAT changes from 0 to 1, and in the case where the standby time Tdly has not elapsed, proceeds to step S06, and in the case where the standby time Tdly has elapsed, proceeds to step S08. In step S06, the current command value calculation portion 33 sets the d-axis and q-axis current command values Ido, Iqo to the d-axis and q-axis switching current values IdPS, IqPS.

[0136] On the other hand, in step S08, the current command value calculation portion 33 determines whether the gradual change of the current command values from the switching current values to the normal current command values is completed after the standby time Tdly elapses, and in the case where the change is not completed, proceeds to step S09, and in the case where the change is completed, proceeds to step S10.

[0137] In step S09, the current command value calculation portion 33 performs processing of gradually changing the d-axis and q-axis current command values Ido, Iqo from the d-axis and q-axis switching current values IdPS, IqPS to the normal d-axis and q-axis current command values IdoD, IqoD.

[0138] On the other hand, in step S10, the current command value calculation portion 33 sets the d-axis and q-axis current command values Ido, Iqo to the normal d-axis and q-axis current command values IdoD, IqoD.

[0139] 1-3-9. Control Action and Effect

[0140] Next, the control action and effect related to the present embodiment will be described. If Laplace transformation is performed on the voltage equation, the following equation is obtained. Since the current flows in the full-phase short-circuit state, the third term on the right side appears.

[0141] [Equation 8]

[0142]

[0143] After the current command value is set to the switching current value and the switching control is started, if a sufficient time elapses, the current value stabilizes to the current command value (the switching current value), and therefore, as shown in the following equation, the transfer function of the target value response in the transfer function of the current controller of Equation (1) can be approximated to 1.

[0144] [Equation 9]

[0145]

[0146] If Equation (9) is substituted into Equation (1), Vdo = Vd and Vqo = Vq are set in Equation (1), and the right side of Equation (8) and the right side of Equation (1) are connected by an equal sign, the following equation is obtained.

[0147] [Math. 10]

[0148]

[0149] In a case where the current command values Id0, Iq0 on the d-axis and q-axis are set to the switching current values IdPS, IqPS on the d-axis and q-axis, the following equation holds.

[0150] [Math. 11]

[0151]

[0152] If equation (11) is substituted into equation (10) and arranged, the following equation is obtained.

[0153] [Math. 12]

[0154]

[0155] Equation (12) means the following case: if the current command values are set to the switching current values, the current values Id, Iq on the d-axis and q-axis after the start of the switching control become constant values of the switching current values IdPS, IqPS on the d-axis and q-axis, which are equivalent to the full-phase short-circuit current. Since the current values on the d-axis and q-axis become constant values, a torque fluctuation does not occur.

[0156] On the other hand, in the conventional method, if the torque command value To is set to 0, the current command values Id0, Iq0 on the d-axis and q-axis are generally set to 0 as shown in the following equation.

[0157] [Math. 13]

[0158]

[0159] Even if equation (13) is substituted into equation (10), the current values Id, Iq on the d-axis and q-axis do not become constant at the switching current values IdPS, IqPS on the d-axis and q-axis, which are equivalent to the full-phase short-circuit current.

[0160] <Comparative Example Control Action>

[0161] Figure 6 A control action involved in the comparative example is shown in FIG. 10. Before time t01, the full-phase short-circuit control is executed, and at the time point of time t01, the current values Id, Iq on the d-axis and q-axis are stabilized in the vicinity of the switching current values IdPS, IqPS on the d-axis and q-axis represented by equation (4). Further, the 1st rotation angle θ1 and the 1st rotation angular velocity ω1 estimated at the time of the full-phase short-circuit are also stabilized.

[0162] At time t02, the execution instruction of the switching control is transmitted, and the switching signal STAT changes from 0 to 1. Thus, the execution of the full-phase short-circuit control ends, the switching control is started to be executed, and the estimation of the rotational angle and the rotational angular velocity at the start of the switching control is started.

[0163] In the comparative example, after the start of the switching control (after time t02), the current command value calculation section 33 sets the d-axis and q-axis current command values Ido, Iqo to the normal d-axis and q-axis current command values IdoD, IqoD set on the basis of the torque command value To. Figure 6 In the example of IdoD = 0, IqoD = 0.

[0164] Thus, at time t02, the deviation of the current value from the current command value in the full-phase short-circuit state becomes large, and thus the manipulated variable based on the current feedback control becomes temporarily too large, and in particular, the q-axis current detection value Iqr greatly deviates from the q-axis current command value Iqo and varies. The torque T varies in proportion to the variation of the q-axis current detection value Iqr. Further, due to the variation of the current detection value with respect to the current command value, the variation of the estimated values of the rotational angle θ and the rotational angular velocity ω becomes large.

[0165] <Control Operation of the Present Embodiment>

[0166] Figure 7 The control operation related to the present embodiment is shown in the example of FIG. 12. Before time tll, the full-phase short-circuit control is executed, and at the time point of time tll, the d-axis and q-axis current values Id, Iq are stabilized in the vicinity of the d-axis and q-axis switching current values IdPS, IqPS represented by formula (4). Further, the first rotational angle θl and the first rotational angular velocity ωl estimated at the time of the full-phase short-circuit are also stabilized.

[0167] At time t12, the execution instruction of the switching control is transmitted, and the switching signal STAT changes from 0 to 1. Thus, the execution of the full-phase short-circuit control ends, the switching control is started to be executed, and the estimation of the rotational angle and the rotational angular velocity at the start of the switching control is started.

[0168] At the time of switching from the full-phase short-circuit control to the switching control (time t12), the current command value calculation section 33 sets the d-axis and q-axis current command values Ido, Iqo to the d-axis and q-axis switching current values IdPS, IqPS. Further, Figure 7In the example of FIG. 10, in a case where the primary delay filter process is considered in the process of calculating the current command values Id0, Iq0 of the d-axis and q-axis, the current command value calculation section 33 sets the current command values Id0, Iq0 of the d-axis and q-axis to the switching current values IdPS, IqPS of the d-axis and q-axis from the start of the execution of the full-phase short-circuit control until the time t12, so that when the switching from the full-phase short-circuit control to the switching control is made (the time when the switching signal STAT changes from 0 to 1), the current command values Id0, Iq0 of the d-axis and q-axis become the switching current values IdPS, IqPS of the d-axis and q-axis.

[0169] In the embodiment, during the period from the start of the switching control until the elapse of the standby time Tdly (the time t12 to the time t13), the current command value calculation section 33 sets the current command values Id0, Iq0 of the d-axis and q-axis to the switching current values IdPS, IqPS of the d-axis and q-axis.

[0170] Further, at the time of the switching from the full-phase short-circuit control to the switching control (the time t12), the initial values of the second rotational angle θ2 and the second rotational angular velocity ω2 at the time of the switching control are set to the first rotational angle θ1 and the first rotational angular velocity ω1 that have been estimated immediately before.

[0171] Therefore, after the switching to the switching control, the deviation of the current detection values of the d-axis and q-axis from the current command values of the d-axis and q-axis becomes small, and the current detection values of the d-axis and q-axis are tracked well without variation with respect to the current command values of the d-axis and q-axis. As a result, the variation of the torque is also suppressed.

[0172] In addition to the setting of the initial values, the tracking of the current detection values with respect to the current command values is also good, and therefore, the estimation accuracy of the first rotational angle θ1 and the first rotational angular velocity ω1 after the switching to the switching control becomes high.

[0173] During the standby time Tdly, the variation of the current values, the variation of the estimated values of the rotational angle θ and the rotational angular velocity ω converge. At the time t13 when the standby time Tdly has elapsed, the current command value calculation section 33 starts to gradually change the current command values Id0, Iq0 of the d-axis and q-axis from the switching current values IdPS, IqPS of the d-axis and q-axis to the normal current command values IdoD, IqoD of the d-axis and q-axis.

[0174] Since the current command values are gradually changed, the current detection values are tracked well with a prescribed control response without largely deviating from the current command values. Thus, the variation of the torque, the variation of the estimated values of the rotational angle θ and the rotational angular velocity ω are suppressed.

[0175] Then, at time t14, the gradual change of the current command value is completed, and after time t14, the switching control is performed in a state where the current command values Id0, Iq0 on the d-axis and q-axis are set to the ordinary current command values Id0D, Iq0D on the d-axis and q-axis.

[0176] 2. Embodiment 2

[0177] The control device 1 according to Embodiment 2 will be described with reference to the drawings. The same structural parts as those of Embodiment 1 described above will be omitted from the description. The basic structure of the alternating-current rotary electric machine 2 and the control device 1 according to this embodiment is the same as that of Embodiment 1, but the setting method of the current command value at the time of switching from the full-phase short-circuit control to the switching control is different from that of Embodiment 1.

[0178] As explained using Equation (6), assuming that the resistance value R of the winding is sufficiently small with respect to the impedance of the inductance of the winding, and R = 0 is set in Equation (4), the d-axis current value Id and the q-axis current value Iq at the time of full-phase short-circuit are expressed by the following equations. The d-axis and q-axis currents of the following equations are current values at which the armature-linkage fluxes interlinking the three-phase windings are minimum (for example, 0), and in this embodiment, the switching current value IdPS on the d-axis and the switching current value IqPS on the q-axis are set.

[0179] [Equation 14]

[0180]

[0181] That is, in this embodiment, when switching from the full-phase short-circuit control to the switching control, the current command value calculation unit 33 sets the current command value to the switching current value at which the magnitude of the armature-linkage fluxes interlinking the three-phase windings is minimum. Specifically, the current command value calculation unit 33 sets the switching current value IdPS on the d-axis and the switching current value IqPS on the q-axis set by Equation (14) as the switching current value.

[0182] According to this structure, the current value at which the armature-linkage fluxes are minimum is close to the current value in the full-phase short-circuit state, and thus at the time of switching, the deviation between the current detection value and the current command value of the switching control can be suppressed from becoming large. Therefore, at the time of switching, the current deviation between the current command value and the current detection value can be made small, the situation in which the operation amount becomes large transitionally and the current value is greatly changed can be suppressed, and the transitionally occurring torque variation can be suppressed.

[0183] In the present embodiment, when switching from the full-phase short-circuit control to the switching control, the current command value calculation section 33 sets the d-axis and q-axis current command values Id0, Iq0 to the switching current values IdPS, IqPS of the d-axis and q-axis, and then gradually changes the d-axis and q-axis current command values Id0, Iq0 from the switching current values IdPS, IqPS of the d-axis and q-axis to the normal d-axis and q-axis current command values IdoD, IqoD normally set in the switching control.

[0184] Further, when switching from the full-phase short-circuit control to the switching control, the current command value calculation section 33 sets the d-axis and q-axis current command values Id0, Iq0 to the switching current values IdPS, IqPS of the d-axis and q-axis, and after the standby time Tdly elapses, gradually changes the d-axis and q-axis current command values Id0, Iq0 from the switching current values IdPS, IqPS of the d-axis and q-axis to the normal d-axis and q-axis current command values IdoD, IqoD normally set in the switching control.

[0185] <Setting of switching current values based on target value Mo = 0 of modulation factor>

[0186] As shown in FIG. 6, the current command value calculation section 33 sets the target value Mo of the modulation factor, as with Embodiment 1. Figure 8

[0187] In the present embodiment, when switching from the full-phase short-circuit control to the switching control, the current command value calculation section 33 sets the target value Mo of the modulation factor to 0, thereby setting the current command value to the switching current value at which the size of the armature link magnetic flux is the smallest.

[0188] When switching from the full-phase short-circuit control to the switching control, the current command value calculation section 33 sets the target value Mo of the modulation factor to 0, and then gradually changes the target value Mo of the modulation factor from 0 to the normal target value MoD of the modulation factor normally set in the switching control.

[0189] When switching from the full-phase short-circuit control to the switching control, the current command value calculation section 33 sets the target value Mo of the modulation factor to 0, and after the standby time Tdly elapses, gradually changes the target value Mo of the modulation factor from 0 to the normal target value MoD of the modulation factor.

[0190] The normal target value MoD of the modulation factor is set to a constant value (for example, 1.2) larger than 0. In addition, the normal target value MoD of the modulation factor can vary based on the operating state such as the torque command value To and the rotational angular velocity ω.

[0191] ​As with Embodiment 1, the current command value calculation section 33 calculates the linkage flux command value Ψ0 based on the target value Mo of the modulation factor. The current command value calculation section 33 calculates the d-axis current command value Id0 and the q-axis current command value Iq0 based on the linkage flux command value Ψ0 and the torque command value To. The calculation method of the d-axis and q-axis current command values Id0, Iq0 is the same as that of the usual d-axis and q-axis current command values IdoD, IqoD of Embodiment 1.

[0192] The target value Mo of the modulation factor is set to 0, whereby the linkage flux command value Ψ0 is set to 0, and the armature linkage flux is set to 0 and the current command value corresponding to the switching current value. In addition, the linkage flux command value Ψ0 can be directly set to 0 without passing through the target value Mo of the modulation factor. Furthermore, the current command value can be directly set to the switching current value without passing through the target value Mo of the modulation factor and the linkage flux command value Ψ0.

[0193] <Flowchart>

[0194] The processing of the control device relating to the switching of the full-phase short-circuit control and the switching control explained above is explained using the flowchart of Figure 9 . The processing of the control device relating to the switching of the full-phase short-circuit control and the switching control explained above is explained using the flowchart of Figure 9 . The processing of the control device relating to the switching of the full-phase short-circuit control and the switching control explained above is explained using the flowchart of

[0195] In step S21, the switching control section 37 determines which of the execution command of the full-phase short-circuit control and the execution command of the switching control is transmitted, and in the case where the execution command of the switching control is transmitted, proceeds to step S22, and in the case where the execution command of the full-phase short-circuit control is transmitted, proceeds to step S23.

[0196] In step S22, the switching control section 37 sets the switching signal STAT = 1, causes the current command value calculation section 33, the voltage command value calculation section 34, and the inverter control section 35 and the like to execute the switching control, and causes the rotation detection section 36 to perform the estimation of the rotation angle and the rotation angular velocity at the time of the switching control.

[0197] In step S23, the switching control section 37 sets the switching signal STAT = 0, causes the inverter control section 35 to execute the full-phase short-circuit control, and causes the rotation detection section 36 to perform the estimation of the rotation angle and the rotation angular velocity at the time of the full-phase short-circuit.

[0198] In step S24, the current command value calculation portion 33 determines whether it is the timing at which the switching signal STAT changes from 0 to 1, and in the case of being the timing at which it changes, proceeds to step S25, and in the case of not being the timing at which it changes, proceeds to step S27. In step S25, the rotation detection portion 36 sets the first rotation angle θ1 and the first rotation angular velocity ω1 at the time of the full-phase short-circuit immediately before the switching as initial values of the second rotation angle θ2 and the second rotation angular velocity ω2 at the time of the switching control.

[0199] Further, in step S26, the current command value calculation portion 33 sets the target value Mo of the modulation factor to 0. In addition, in the case where the primary delay filter processing is performed in the process of calculating the current command values Id0, Iq0 of the d-axis and the q-axis in accordance with the target value Mo of the modulation factor, the current command value calculation portion 33 can set the target value Mo of the modulation factor to 0 in the execution of the full-phase short-circuit control so that when the switching from the full-phase short-circuit control to the switching control (the timing at which the switching signal STAT changes from 0 to 1), the current command values Id0, Iq0 of the d-axis and the q-axis become values corresponding to Mo = 0 (the switching current values IdPS, IqPS of the d-axis and the q-axis in the present example). Alternatively, the current command value calculation portion 33 can reset internal operation values such as the last operation value of the primary delay filter processing to values corresponding to Mo = 0 so that when the switching from the full-phase short-circuit control to the switching control (the timing at which the switching signal STAT changes from 0 to 1), the current command values Id0, Iq0 of the d-axis and the q-axis become values corresponding to Mo = 0 (the switching current values IdPS, IqPS of the d-axis and the q-axis in the present example).

[0200] In step S27, the current command value calculation portion 33 determines whether the standby time Tdly has elapsed after the switching signal STAT changes from 0 to 1, and in the case of not having elapsed, proceeds to step S26, and in the case of having elapsed, proceeds to step S28. In step S26, the current command value calculation portion 33 sets the target value Mo of the modulation factor to 0.

[0201] On the other hand, in step S28, the current command value calculation portion 33 determines whether the gradual change of the target value Mo of the modulation factor from 0 to the target value MoD of the normal modulation factor, which is performed after the standby time Tdly has elapsed, is completed, and in the case of not being completed, proceeds to step S29, and in the case of being completed, proceeds to step S30.

[0202] In step S29, the current command value calculation portion 33 performs processing of gradually changing the target value Mo of the modulation factor from 0 to the target value MoD of the normal modulation factor.

[0203] On the other hand, in step S30, the current command value calculation portion 33 sets the target value Mo of the modulation factor to the target value MoD of the normal modulation factor.

[0204] <Control Action>

[0205] Figure 10 The control action according to the present embodiment is shown in FIG. 34. Before time t31, the full-phase short-circuit control is executed, and at the time point of time t31, the current values Id, Iq of the d-axis and q-axis are stabilized in the vicinity of the current values of the d-axis and q-axis in the full-phase short-circuit state represented by Expression (4). Further, the 1st rotation angle θ1 and the 1st rotation angular velocity ω1 estimated at the time of the full-phase short-circuit are also stabilized.

[0206] At time t32, the execution instruction of the switching control is transmitted, and the switching signal STAT is changed from 0 to 1. Therefore, the execution of the full-phase short-circuit control ends, the switching control is started to be executed, and the estimation of the rotation angle and the rotation angular velocity at the time of the switching control is started.

[0207] At the time of switching from the full-phase short-circuit control to the switching control (time t32), the current command value calculation section 33 sets the target value Mo of the modulation factor to 0, and sets the current command values Ido, Iqo of the d-axis and q-axis to the switching current values IdPS, IqPS of the d-axis and q-axis in which the armature link magnetic flux is 0, represented by Expression (14). Further, the target value Mo of the modulation factor is set to 0 in the execution of the full-phase short-circuit control before time t32, so that when the switching control is switched from the full-phase short-circuit control (at the time when the switching signal STAT is changed from 0 to 1), the current command values Ido, Iqo of the d-axis and q-axis become the switching current values IdPS, IqPS of the d-axis and q-axis corresponding to Mo = 0. Figure 10 In the example of FIG. 34, a case where the primary delay filter processing is performed in the process of calculating the current command values Ido, Iqo of the d-axis and q-axis according to the target value Mo of the modulation factor is considered, the current command value calculation section 33 sets the target value Mo of the modulation factor to 0 in the execution of the full-phase short-circuit control before time t32, so that when the switching control is switched from the full-phase short-circuit control (at the time when the switching signal STAT is changed from 0 to 1), the current command values Ido, Iqo of the d-axis and q-axis become the switching current values IdPS, IqPS of the d-axis and q-axis corresponding to Mo = 0.

[0208] In the present embodiment, during the period from the start of the switching control to the elapse of the standby time Tdly (time t32 to time t33), the current command value calculation section 33 sets the target value Mo of the modulation factor to 0, and sets the current command values Ido, Iqo of the d-axis and q-axis to the switching current values IdPS, IqPS of the d-axis and q-axis.

[0209] Further, at the time of switching from the full-phase short-circuit control to the switching control (time t32), the initial values of the 2nd rotation angle θ2 and the 2nd rotation angular velocity ω2 at the time of the switching control are set to the 1st rotation angle θ1 and the 1st rotation angular velocity ω1 estimated at the time of the full-phase short-circuit before.

[0210] The current command values Id0, Iq0 of the d-axis and q-axis, particularly the current command value Id0 of the d-axis, are set near the current values of the d-axis and q-axis in the full-field short-circuit state, and after switching to the switching control, the deviation between the current detection values of the d-axis and q-axis and the current command values of the d-axis and q-axis becomes small, and the current detection values of the d-axis and q-axis are tracked well with respect to the current command values of the d-axis and q-axis. As a result, the variation in torque is also suppressed.

[0211] Further, after switching to the switching control, the torque becomes 0, which is closer to the torque command value To than in Embodiment 1.

[0212] In addition to the setting of the initial values, the tracking of the current detection values with respect to the current command values is also good, and therefore, the estimation accuracy of the 1st rotation angle θ1 and the 1st rotation speed ω1 after switching to the switching control becomes high.

[0213] During the standby time Tdly, the variation in the current values, the variation in the estimated values of the rotation angle θ and the rotation speed ω converge. At the time t33 after the passage of the standby time Tdly, the current command value calculation section 33 starts gradually changing the target value Mo of the modulation factor from 0 to the target value MoD of the normal modulation factor. As a result, the current command values Id0, Iq0 of the d-axis and q-axis gradually change from the values corresponding to Mo = 0 to the values corresponding to Mo = Mod.

[0214] Since the current command values gradually change, the current detection values are tracked well with a prescribed control response without greatly deviating from the current command values. Thus, the variation in torque, the variation in the estimated values of the rotation angle θ and the rotation speed ω are suppressed.

[0215] At the time t34, the gradual change of the target value Mo of the modulation factor is completed, and after the time t34, the switching control is performed in a state where the target value Mo of the modulation factor is set to the target value MoD of the normal modulation factor.

[0216] <Effect of Setting the Current Command Value to Minimize the Armature Flux>

[0217] Next, the additional effect obtained by setting the current command value to minimize the armature flux will be described. Figure 11 is an example showing the magnitude of the variation in the estimated value of the rotation speed ω after switching from the full-field short-circuit control to the switching control in the case where the q-axis inductance Lq used by the control device 1 has an error (hereinafter, referred to as the amount of variation in the estimated speed after switching). Figure 11The amount of variation in the post-switch estimated angular velocity when the current command value is set to the full-phase short-circuit current value (hereinafter, referred to as the full-phase short-circuit current value case) is shown in the graph in the case where the error in the q-axis inductance Lq is varied, in each of the error cases.

[0218] As is clear from the graph, in the case where there is no error in the q-axis inductance Lq or the error is in the positive direction, the amount of variation in the post-switch estimated angular velocity in the full-phase short-circuit current value case is smaller than that in the flux-linkage-minimum current value case. On the other hand, in the case where there is an error in the q-axis inductance Lq in the negative direction, the amount of variation in the post-switch estimated angular velocity in the flux-linkage-minimum current value case is smaller than that in the full-phase short-circuit current value case.

[0219] This has the following effect: setting the current command value to the flux-linkage-minimum current value causes the current command value to deviate from the full-phase short-circuit current value, and the variation in the estimated angular velocity is large. On the other hand, by setting the current command value to the flux-linkage-minimum current value, the estimation error of the q-axis current of the adaptive observer due to the error in the q-axis inductance Lq in the negative direction is small, and the variation in the estimated angular velocity also becomes small.

[0220] Overall, from the error in the positive direction and the error in the negative direction, the variation in the estimated angular velocity is smaller when the current command value is set to the flux-linkage-minimum current value, and therefore, the embodiment 2 has the advantage that it can be easily applied even in the case where the q-axis inductance Lq cannot be accurately obtained.

[0221] 3. Embodiment 3

[0222] The control device 1 according to the embodiment 3 will be described with reference to the accompanying drawings. The same structure as in the above-described embodiment 1 will not be described. The basic structure of the alternating-current rotary electric machine 2 and the control device 1 according to the embodiment 3 is the same as that of the embodiment 1, but the method of setting the switching current value is different from that of the embodiment 1.

[0223] In the embodiment, the current command value calculation unit 33 sets the switching current value based on the detected value of the current during execution of the full-phase short-circuit control.

[0224] According to this structure, even in the case where the characteristics of the alternating-current rotary electric machine 2 have varied due to variation factors such as chronological change, production deviation, temperature characteristics, and the like, the switching current value can be set with high precision based on the detected value of the current during execution of the full-phase short-circuit control.

[0225] In the present embodiment, as shown in FIG. 3, the current command value calculation section 33 learns the d-axis current detection value Idr and the q-axis current detection value Iqr in the execution of the full-phase short-circuit control. For example, the current command value calculation section 33 statistically processes the d-axis current detection value Idr and the q-axis current detection value Iqr in the execution of the full-phase short-circuit control, and calculates a d-axis current learning value IdL and a q-axis current learning value IqL in the execution of the full-phase short-circuit control. The d-axis current learning value IdL and the q-axis current learning value IqL correspond to the switching current values IdPS, IqPS of the d-axis and the q-axis. The statistical processing uses an averaging process, a low-pass filter process, a least square method, or the like. The learning values are stored in a storage device such as a RAM. Then, when switching from the full-phase short-circuit control to the switching control (at the time when the switching signal STAT changes from 0 to 1), the current command value calculation section 33 sets the d-axis and q-axis current command values Ido, Iqo to the d-axis current learning value IdL and the q-axis current learning value IqL as the switching current values of the d-axis and the q-axis. Figure 12

[0226] In addition, although the illustration of the flowchart relating to the present embodiment is omitted, in step S06 of Embodiment 1, Figure 5 the current command value calculation section 33 sets the d-axis and q-axis current command values Ido, Iqo to the d-axis current learning value IdL and the q-axis current learning value IqL as the switching current values IdPS, IqPS of the d-axis and the q-axis. Further, in step S03 of Embodiment 2, Figure 5 the current command value calculation section 33 statistically processes the d-axis current detection value Idr and the q-axis current detection value Iqr in the execution of the full-phase short-circuit control, and calculates a d-axis current learning value IdL and a q-axis current learning value IqL in the execution of the full-phase short-circuit control.

[0227] <Conversion Example>

[0228] (1) In each of the above embodiments, the use of the alternating-current rotary electric machine is not particularly specified. For example, the alternating-current rotary electric machine is preferably used as a driving source of a wheel of a vehicle. In the present application, the torque variation at the time of switching from the full-phase short-circuit control to the switching control is suppressed, so that the vibration felt by the driver is reduced, and the comfort of the driver is improved. In addition, the alternating-current rotary electric machine can be used as a driving source of various devices other than the wheel of the vehicle.

[0229] (2) In each of the above embodiments, the alternating-current rotary electric machine of the permanent magnet type is exemplified. However, if the alternating-current rotary electric machine of the field winding type or the like that generates an induced voltage at the time of rotation is used, an arbitrary structure of the alternating-current rotary electric machine can be used.

[0230] ​(3) In each of the above-described embodiments, the case where three-phase windings are provided is described as an example. However, if the number of phases of the windings is multiphase, the number of phases can be set to two, four, or any number of phases.

[0231] (4) In each of the above-described embodiments, the case where one set of three-phase windings and an inverter are provided is described as an example. However, two or more sets of multiphase windings and inverters can be provided, and each set of multiphase windings and inverters can be controlled in the same manner as in each of the embodiments.

[0232] (5) In each of the above-described embodiments, the case where the current command value calculation unit 33 uses the cross-linkage flux command value Ψo as an intermediate parameter, changes the cross-linkage flux command value Ψo based on the target value Mo of the modulation factor, and sets the current command value based on the cross-linkage flux command value Ψo is described as an example. However, the current command value calculation unit 33 can set the current command value without using the cross-linkage flux command value Ψo. For example, the current command value calculation unit 33 can use a voltage deficiency ratio as an intermediate parameter, change the voltage deficiency ratio based on the target value Mo of the modulation factor, and set the current command value based on the voltage deficiency ratio, as disclosed in Japanese Patent Application Publication No. 2012-200073.

[0233] In addition, the current command value calculation unit 33 can set a general current command value using various known current vector controls. For example, the current command value calculation unit 33 can set the general d-axis and q-axis current command values IdoD, IqoD based on the torque command value To, the rotational angular velocity ω, and the power supply voltage VDC, or the like, using maximum torque current control or flux-weakening control, and set the d-axis and q-axis current command values Ido, Iqo to the d-axis and q-axis switching current values IdPS, IqPS described in each of the above-described embodiments when switching from the full-phase short-circuit control to the switching control.

[0234] (6) In each of the above-described embodiments, the case where the rotational angle θ and the rotational angular velocity ω are estimated based on the current detection values and the like without using an angle sensor that detects the rotational angle is described as an example. However, a Hall element, an encoder, a resolver, or an angle sensor can be provided, and the rotational angle θ and the rotational angular velocity ω can be estimated based on the output signal of the angle sensor. In this case, the standby time Tdly can be set to 0.

[0235] The present application describes exemplary embodiments, but the various features, modes, and functions described in the embodiments are not limited to the application of specific embodiments and can be applied to the embodiments individually or in various combinations. Therefore, it can be considered that an infinite number of modifications not exemplified are also included in the technical scope disclosed in the present application. For example, a case where at least one structural element is modified, a case where something is added, or a case where something is omitted is included.

[0236] Description of labels

[0237] 1 Control device for AC rotating motor

[0238] 2 AC rotating motors

[0239] 20 Inverter

[0240] 32 Current detection unit

[0241] 33 Current command value calculation unit

[0242] 34 Voltage command value calculation unit

[0243] 35 Inverter control unit

[0244] IdPS d-axis switching current value

[0245] IqPS q-axis switching current value

[0246] IdoD Normal d-axis current command value

[0247] IqoD Normal q-axis current command value

[0248] Ido d-axis current command value

[0249] Iqo q-axis current command value

[0250] Idr d-axis current detection value

[0251] Iqr q-axis current detection value

[0252] Ld d-axis inductance

[0253] Lq q-axis inductance

[0254] Mo Target value of modulation rate

[0255] MoD Normal modulation rate target value

[0256] Tdly standby time

[0257] To torque command value

[0258] Ψo Interlinkage flux command value

[0259] θ rotation angle

[0260] ω is the angular velocity of rotation.

Claims

1. A control device of an alternating-current rotary electric machine, An alternating current rotating electric machine having a stator and a rotor provided with a multiphase winding is controlled via an inverter, characterized in that comprising: a current detection section that detects a current flowing through the multiphase winding; a current command value calculation section that sets a current command value; a voltage command value calculation section that calculates a voltage command value based on the current command value and a detected value of the current; and an inverter control section that, based on the voltage command value, switchingly performs switching control of applying a voltage to the multiphase winding by turning on and off a plurality of switching elements possessed by the inverter, and full-phase short-circuit control of turning on and off the plurality of switching elements to cause the multiphase winding to be short-circuited to each other, when switching from the full-phase short-circuit control to the switching control, the current command value calculation section sets the current command value to a value equivalent to a current flowing at the time of the full-phase short-circuit control, that is, a switching current value, the current command value calculation section sets a current command value of a d-axis and a current command value of a q-axis as the current command value, the voltage command value calculation section calculates the voltage command value based on the current command value of the d-axis, the current command value of the q-axis, a detected value of a current of the d-axis, and a detected value of a current of the q-axis, the current command value calculation section sets a rotational angular velocity at an electrical angle of the rotor to ω, sets an inductance of the d-axis to Ld, sets an inductance of the q-axis to Lq, sets a magnet linkage flux of the magnet of the rotor to Ψp, sets a resistance value of the winding to R, sets the switching current value of the d-axis to IdPS, and sets the switching current value of the q-axis to IqPS, and calculates the switching current value of the d-axis and the switching current value of the q-axis as the switching current value using a calculation formula of [Mathematical Formula 1]. [Mathematical Formula 1] 2. The control device of the alternating-current rotary electric machine according to claim 1, characterized in that the current command value calculation section sets the switching current value based on the rotational angular velocity of the rotor.

3. The control device of the alternating-current rotary electric machine according to claim 1, characterized in that the current command value calculation section sets the switching current value based on a detected value of the current in the execution of the full-phase short-circuit control.

4. A control device of an alternating-current rotary electric machine, comprising: An alternating current rotating electric machine having a stator and a rotor provided with a multiphase winding is controlled via an inverter, characterized in that a current detection section that detects a current flowing through the multiphase winding; a current command value calculation section that sets a current command value; a voltage command value calculation section that calculates a voltage command value based on the current command value and a detected value of the current; and an inverter control section that, based on the voltage command value, switchingly performs switching control of applying a voltage to the multiphase winding by turning on and off a plurality of switching elements possessed by the inverter, and full-phase short-circuit control of turning on and off the plurality of switching elements to cause the multiphase winding to be short-circuited to each other, when switching from the full-phase short-circuit control to the switching control, the current command value calculation section sets the current command value to a value in which a magnitude of an armature linkage flux of the multiphase winding is the smallest, that is, a switching current value, ​ The current command value calculation section sets a current command value of the d-axis and a current command value of the q-axis as the current command value, The voltage command value calculation section calculates the voltage command value based on the current command value of the d-axis, the current command value of the q-axis, a current detection value of the d-axis, and a current detection value of the q-axis, The current command value calculation section sets an inductance of the d-axis as Ld, sets a magnet linkage flux of the rotor as Ψp, sets a switching current value of the d-axis as IdPS, sets a switching current value of the q-axis as IqPS, sets the switching current value of the d-axis and the switching current value of the q-axis set by a formula of [Mathematical Formula 2] [Mathematical Formula 2] I qPS ＝0 as the switching current value.

5. The control device of the alternating-current rotary electric machine according to claim 4, wherein The current command value calculation section calculates the current command value based on a linkage flux command value and a torque command value, When switching from the full-phase short-circuit control to the switching control, the current command value is set to the switching current value by setting the linkage flux command value to 0.

6. The control device of the alternating-current rotary electric machine according to claim 4 or 5, wherein The current command value calculation section calculates a linkage flux command value based on a modulation factor target value, and calculates the current command value based on the linkage flux command value and a torque command value, When switching from the full-phase short-circuit control to the switching control, the current command value is set to the switching current value by setting the modulation factor target value to 0 to set the linkage flux command value to 0.

7. The control device of the alternating-current rotary electric machine according to any one of claims 1 to 5, wherein When switching from the full-phase short-circuit control to the switching control, the current command value calculation section gradually changes the current command value from the switching current value to a normal current command value normally set in the switching control after setting the current command value to the switching current value.

8. The control device of the alternating-current rotary electric machine according to any one of claims 1 to 5, wherein When switching from the full-phase short-circuit control to the switching control, the current command value calculation section sets the current command value to the switching current value, and gradually changes the current command value from the switching current value to a normal current command value normally set in the switching control after elapsing of a standby time.

9. The control device of the alternating-current rotary electric machine according to claim 8, wherein The standby time is set corresponding to a period from after the start of the switching control to when the current stabilizes to the switching current value.

10. The control device of the alternating-current rotary electric machine according to any one of claims 1 to 5, wherein The alternating-current rotary electric machine is a driving force source of a wheel of a vehicle.

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