Phase estimation device and vehicle

Abstract

To prevent a drive voltage from being limited in order to estimate a phase of a motor.SOLUTION: A phase estimation device 200 includes: a motor 14 in which a motor coil 14U, a motor coil 14V, and a motor coil 14W are delta-connected; a battery 11 that supplies a drive power of the motor 14; a motor driver 13 that converts a DC power input from a battery 11 into an AC power and supplies the AC power to each phase of the motor 14; and a phase estimation part 312 that estimates a phase θ of the motor 14. The motor coil 14U, the motor coil 14V, and the motor coil 14W are configured such that an impedance of the motor coil of at least one phase is different from the impedance of the motor coils of the other phases. The phase estimation part 312 estimates the phase θ of the motor 14 based on a current value of the current flowing through each of the motor coil 14U, the motor coil 14V, and the motor coil 14W.SELECTED DRAWING: Figure 1

Description

[Technical Field]

[0001] The present invention relates to a phase estimation device and a vehicle. [Background technology]

[0002] Conventionally, techniques for estimating the phase of a motor are known. For example, Patent Document 1 discloses high-frequency superposition sensorless control of a motor. Specifically, a three-phase voltage command value is output based on a signal obtained by superimposing a high-frequency voltage command output from a high-frequency frequency / amplitude setting means onto a voltage command signal output from a current control means. Also, the rotor magnetic pole position of the motor is estimated from the measured values ​​of the U-phase current and W-phase current among the currents flowing through the motor. Furthermore, in recent years, efforts to realize a low-carbon or carbon-free society have become more active, and research and development into electrification technologies is being conducted in order to reduce CO2 emissions and improve energy efficiency in vehicles. [Prior art documents] [Patent documents]

[0003] [Patent Document 1] Japanese Patent Application Laid-Open No. 2004-343833 Summary of the Invention [Problem to be solved by the invention]

[0004] However, the technique described in Patent Document 1 requires superimposing a high-frequency voltage command on a three-phase voltage command value in order to estimate the rotor magnetic pole position, which poses a problem in that the drive voltage is limited by the amount of the high frequency superimposed. The present invention aims to solve the above-mentioned problem by suppressing the limitation of the drive voltage due to the estimation of the motor phase, which in turn contributes to improving energy efficiency. [Means for solving the problem]

[0005] One aspect of the present invention is a motor having three-phase windings delta-connected, a battery that supplies drive power to the motor, a drive circuit that converts DC power input from the battery into AC power and supplies the AC power to each phase of the motor, and a phase estimator that estimates the phase of the motor, wherein the impedance of at least one of the three-phase windings is different from the impedance of the other phase windings. This leads to an unbalanced state The phase estimation unit is a phase estimation device configured as described above, and estimates the phase of the motor based on a current value corresponding to a harmonic of the rotation frequency of the motor that flows through the winding. [Effects of the Invention]

[0006] According to the present invention, it is possible to prevent the drive voltage from being limited in order to estimate the phase of the motor. [Brief explanation of the drawings]

[0007] [Figure 1] 1 is a diagram showing an example of the configuration of a vehicle drive control device according to an embodiment of the present invention; [Figure 2] FIG. 1 is a diagram showing an example of the configuration of a phase estimation apparatus according to an embodiment of the present invention. [Figure 3] FIG. 2 is a diagram showing an example of the configuration of a control device. [Figure 4] 6 is a flowchart showing an example of processing of the control device according to the present embodiment. [Figure 5] FIG. 10 is a diagram showing a first modified example of a motor coil that constitutes a motor. [Figure 6] FIG. 10 is a diagram showing a second modified example of a motor coil that constitutes a motor. [Figure 7] FIG. 1 is a diagram showing an example of the configuration of a conventional vehicle drive control device. [Figure 8] FIG. 1 is a diagram showing an example of the configuration of a conventional control device. DETAILED DESCRIPTION OF THE INVENTION

[0008] Hereinafter, an embodiment of the present invention will be described with reference to the drawings.

[0009] [1. Configuration of a conventional vehicle drive control device] First, the configuration of a conventional vehicle drive control device 100A that performs so-called sensorless control without a motor rotation angle sensor will be described with reference to Fig. 7. Fig. 7 is a diagram showing an example of the configuration of the conventional vehicle drive control device 100A. The vehicle drive control device 100A is mounted on a vehicle VC and controls the drive of the vehicle VC.

[0010] As shown in FIG. 7, the vehicle drive control device 100A includes a motor drive circuit 1A, a driver drive circuit 2A, and a control device 3A. The motor drive circuit 1A is a circuit that drives a motor 14A, and includes a battery 11, a capacitor 12, and a motor driver 13A.

[0011] The battery 11 supplies power to the motor 14A via the motor driver 13A.

[0012] Capacitor 12 is disposed between plus terminal 13P and minus terminal 13N of motor driver 13A. Capacitor 12 suppresses changes in the output voltage of battery 11 that accompany the opening and closing of the switching elements of motor driver 13A, as well as suppresses surge voltages and surge currents that accompany the opening and closing of the switching elements. Capacitor 12 is a so-called smoothing capacitor.

[0013] The motor driver 13A is composed of MOSFETs (Metal-Oxide-Semiconductor Field Effect Transistors) 13H1, 13H2, 13H3, 13L1, 13L2, and 13L3. Each of these six MOSFETs is turned on and off based on an instruction from the driver driving circuit 2A. The motor driver 13A has a positive terminal 13P and a negative terminal 13N. The positive terminal 13P is connected to the positive side of the battery 11. The negative terminal 13N is connected to the negative side of the battery 11.

[0014] The MOSFET 13H1, the MOSFET 13H2, and the MOSFET 13H3 are connected to the positive terminal 13P. The MOSFET 13L1, the MOSFET 13L2, and the MOSFET 13L3 are connected to the negative terminal 13N. The motor driver 13A corresponds to an example of a "drive circuit." The voltage sensor SV detects a voltage value V between the plus terminal 13P and the minus terminal 13N. The voltage value V detected by the voltage sensor SV is output to the control device 3A.

[0015] The motor 14A is, for example, a three-phase synchronous motor using permanent magnets. As shown in Fig. 7, the motor 14A includes a motor coil 14UA, a motor coil 14VA, and a motor coil 14WA. The motor coils 14UA, 14VA, and 14WA are delta-connected. The motor coils 14UA, 14VA, and 14WA are configured to be in a balanced state.

[0016] The balanced state is a state in which the impedances of motor coil 14UA, motor coil 14VA, and motor coil 14WA are all equal. That is, motor coil 14UA, motor coil 14VA, and motor coil 14WA have the same configuration. In other words, the number of parallel coils in motor coil 14UA, the number of parallel coils in motor coil 14VA, and the number of parallel coils in motor coil 14WA are the same ("4" in FIG. 7). Furthermore, the number of turns in each coil in motor coil 14UA, the number of turns in each coil in motor coil 14VA, and the number of turns in each coil in motor coil 14WA are the same.

[0017] Current sensors SA1, SA2, and SA3 are disposed between motor 14A and motor driver 13A. Current sensor SA1 detects a current value A1 of a current flowing through motor coil 14VA. Current sensor SA2 detects a current value A2 of a current flowing through motor coil 14UA. Current sensor SA3 detects a current value A3 of a current flowing through motor coil 14WA. The current values ​​A1, A2, and A3 detected by the current sensors SA1, SA2, and SA3 are output to the control device 3A.

[0018] The control device 3A acquires a voltage value V from the voltage sensor SV. The voltage value V is the voltage value of the drive voltage applied from the battery 11 to the motor 14A. The control device 3A acquires the current value A1, the current value A2, and the current value A3 from the current sensor SA1, the current sensor SA2, and the current sensor SA3. The control device 3A estimates the phase θ of the motor 14A based on the voltage value V, the current value A1, the current value A2, and the current value A3, and performs vector control on the driver circuit 2A. The driver driving circuit 2A performs vector control of the motor driver 13A in accordance with instructions from the control device 3A. That is, the driver driving circuit 2A controls the on / off of each of the six MOSFETs that make up the motor driver 13A in accordance with instructions from the control device 3A.

[0019] One terminal of motor coil 14UA (the upper right terminal in FIG. 1) is connected to plus terminal 13P via MOSFET 13H1, and the other terminal of motor coil 14UA is connected to minus terminal 13N via MOSFET 13L2. Therefore, when a current is to flow through the motor coil 14UA, the driver driving circuit 2A turns on the MOSFET 13H1 and MOSFET 13L2, and turns off the MOSFET 13H2, MOSFET 13H3, MOSFET 13L1, and MOSFET 13L3.

[0020] One terminal of the motor coil 14VA (the upper left terminal in FIG. 1) is connected to the plus terminal 13P via a MOSFET 13H3, and the other terminal of the motor coil 14VA is connected to the minus terminal 13N via a MOSFET 13L1. Therefore, when a current is to flow through the motor coil 14VA, the driver driving circuit 2A turns on the MOSFET 13H1 and the MOSFET 13L3, and turns off the MOSFET 13H2, the MOSFET 13H3, the MOSFET 13L1, and the MOSFET 13L2.

[0021] One terminal of motor coil 14WA (the terminal on the left side in FIG. 1) is connected to plus terminal 13P via MOSFET 13H2, and the other terminal of motor coil 14VA is connected to minus terminal 13N via MOSFET 13L3. 7, when a current is to flow through the motor coil 14WA, the driver driving circuit 2A turns on the MOSFET 13H2 and MOSFET 13L3, and turns off the MOSFET 13H1, MOSFET 13H3, MOSFET 13L1, and MOSFET 13L2.

[0022] As described above, by controlling the on / off of each of the six MOSFETs that make up motor driver 13A, the DC voltage of battery 11 is applied to each of motor coils 14UA, 14VA, and 14WA. Note that a square wave voltage is applied to each of motor coils 14UA, 14VA, and 14WA. The square wave voltage is expressed as the sum of an infinite series of sine waves containing odd-order frequencies of the fundamental frequency FM of the motor 14A. Therefore, the currents flowing through the motor coils 14UA, 14VA, and 14WA each contain a third harmonic.

[0023] Next, the configuration of the control device 3A in the conventional vehicle drive control device 100A will be described with reference to Fig. 8. Fig. 8 is a diagram showing an example of the configuration of the conventional control device 3A. As shown in FIG. 8, the control device 3A includes a three-phase / two-phase converter 331A, a current controller 332A, a phase estimator 333A, and a two-phase / three-phase converter 334A.

[0024] The three-phase / two-phase converter 331A receives a three-phase current I' UVW is input. Three-phase current I' UVW is composed of a current value A1, a current value A2, and a current value A3. The three-phase / two-phase converter 331A converts the three-phase current I' UVW γδ general coordinate system two-phase current I' γδ and convert it into two-phase current I' γδ Output. Two-phase current I' output from three-phase / two-phase converter 331A γδ is input to the phase estimator 333A. The phase estimator 333A calculates the two-phase current I' γδ Based on this, the phase θ of the motor 14A is estimated by synchronous detection processing and output. Furthermore, the phase estimator 333A calculates the drive voltage command value V γδ The harmonic command voltage V is added to γδh The phase estimator 333A calculates the torque command current I γδ and the two-phase current I' γδ and the harmonic command voltage V γδh is calculated, and the harmonic command voltage V γδh Output.

[0025] The current controller 332A receives a torque command current I calculated based on the voltage value V. γδ and the two-phase current I' output from the three-phase / two-phase converter 331A. γδ The current controller 332A receives the difference between the torque command current I γδ and two-phase current I' γδ From the difference between γδ Output. The two-phase / three-phase converter 334A receives the drive voltage command value V γδ and the harmonic command voltage V output from the phase estimator 333A. γδh The two-phase / three-phase converter 334A receives the phase θ output from the phase estimator 333A. The two-phase / three-phase converter 334A receives the driving voltage command value V γδ and harmonic command voltage V γδh and the phase θ, the three-phase voltage command value V UVWis calculated and output to the motor driver 13A via the driver drive circuit 2A. In addition, the three-phase current I' UVW , and two-phase current I' γδ Each of the harmonic command voltages V γδh The high frequency current corresponding to

[0026] Next, a vehicle drive control device 100 according to this embodiment will be described with reference to Fig. 1. Fig. 1 is a diagram showing an example of the configuration of the vehicle drive control device 100 according to this embodiment. First, with reference to FIG. 1, differences between the vehicle drive control device 100 and the vehicle drive control device 100A described with reference to FIG. 7 will be described.

[0027] The vehicle drive control device 100 includes a phase estimation device 200. The phase estimation device 200 estimates the phase θ of the motor 14. The phase estimation device 200 includes a phase estimation unit 312 .

[0028] 7 in that the motor 14 controlled by the vehicle drive control device 100 is configured so that the motor coils 14U, 14V, and 14W are in an unbalanced state. The unbalanced state of the motor coils 14U, 14V, and 14W is a state in which the impedance of at least one of the motor coils 14UA, 14VA, and 14WA differs from the impedance of the other two motor coils. That is, for example, as shown in FIG. 1, the number of coils connected in parallel in each of the motor coils 14U and 14V is "4", but the number of coils connected in parallel in the motor coil 14W is "5". The motor coil 14W is configured by connecting one coil X in parallel to the motor coil 14WA shown in FIG. The motor coil 14U corresponds to, for example, an example of a "first phase winding." The motor coil 14V corresponds to an example of a "second phase winding." The motor coil 14W corresponds to, for example, an example of a "third phase winding."

[0029] In this embodiment, a case will be described in which the number of parallel connections of the motor coil 14V matches the number of parallel connections of the motor coil 14U and the number of parallel connections of the motor coil 14W is greater than the number of parallel connections of the motor coil 14U, but the embodiment is not limited to this. For example, the number of parallel connections of the motor coil 14W may match the number of parallel connections of the motor coil 14U and the number of parallel connections of the motor coil 14V may be greater than the number of parallel connections of the motor coil 14U. Alternatively, the number of parallel connections of the motor coil 14W may match the number of parallel connections of the motor coil 14V and the number of parallel connections of the motor coil 14U may be greater than the number of parallel connections of the motor coil 14V.

[0030] Furthermore, in this embodiment, a case is described in which the number of parallel coils of motor coil 14W is one more than the number of parallel coils of motor coil 14U and the number of parallel coils of motor coil 14V, but the embodiment is not limited to this. For example, the number of parallel coils of motor coil 14W may be two more than the number of parallel coils of motor coil 14U and the number of parallel coils of motor coil 14V. Furthermore, for example, the number of parallel coils of motor coil 14W may be three or more more than the number of parallel coils of motor coil 14U and the number of parallel coils of motor coil 14V. The greater the difference between the number of parallel coils of motor coil 14W, the number of parallel coils of motor coil 14U, and the number of parallel coils of motor coil 14V, the more accurate the estimation by phase estimation device 200. The smaller the difference between the number of parallel coils of motor coil 14W, the number of parallel coils of motor coil 14U, and the number of parallel coils of motor coil 14V, the more efficient the driving of motor 14.

[0031] The motor coil 14U, the motor coil 14V, and the motor coil 14W correspond to an example of a "three-phase winding." The motor 14 drives the vehicle VC with power supplied from the battery 11 via the motor driver 13. The vehicle VC is, for example, a motorbike (motorcycle), a so-called "saddle-ride type vehicle."

[0032] In this embodiment, the vehicle VC is a motorbike (two-wheeled motor vehicle), a so-called "saddle-ride type vehicle," but is not limited to this. The vehicle VC may be, for example, a four-wheeled passenger car or a four-wheeled large vehicle. The vehicle VC may also be, for example, a work vehicle such as a tractor.

[0033] Next, the phase estimation device 200 will be described with reference to FIG. The phase estimation device 200 includes a phase estimation unit 312 . The control device 3 will be further described with reference to FIGS.

[0034] [2. Principle of phase estimation by phase estimator] As shown in Figure 7, when motor coil 14UA, motor coil 14VA, and motor coil 14WA are balanced, the currents (iua, iva, iwa) flowing through motor coil 14UA, motor coil 14VA, and motor coil 14WA, respectively, are as shown in the following equations (1), (2), and (3). Current value iua indicates the current value of the current flowing through motor coil 14UA at a frequency three times the rotational frequency FM of motor 14. Current value iva indicates the current value of the current flowing through motor coil 14VA at a frequency three times the rotational frequency FM of motor 14. Current value iwa indicates the current value of the current flowing through motor coil 14WA at a frequency three times the rotational frequency FM of motor 14. iua=I×sin3ωt (1) iva=I×sin(3ωt-2π)=I×sin3ωt (2) iwa=I×sin(3ωt-4π)=I×sin3ωt (3)

[0035] Here, coefficient I indicates the amplitude of the current, coefficient ω indicates the rotational angular velocity of motor 14, and coefficient t indicates time. The magnitude of the current amplitude I is determined based on the voltage applied across the motor coil of each phase and the impedance of the motor coil. Because the voltages applied to the motor coils of each of the three phases are equal and the impedances of the motor coils of each of the three phases are equal, the amplitude of the current flowing through the coils of each phase is equal. That is, among the currents flowing through motor coil 14UA, motor coil 14VA, and motor coil 14WA, the current values ​​at a frequency three times the rotation frequency FM of motor 14 match each other. Similarly, among the currents flowing through motor coil 14UA, motor coil 14VA, and motor coil 14WA, the current values ​​at a frequency that is an integer multiple of "3" the rotation frequency FM also match each other.

[0036] As a result, when motor coils 14UA, 14VA, and 14WA are balanced, a current with a frequency three times the rotational frequency FM of motor 14 circulates within the delta connection. The direction of the current circulating within the delta connection is the same as the direction of the current flowing from motor driver 13A. For example, in the case of FIG. 7, the current flowing from motor driver 13A to coil 14WA flows from between coils 14UA and 14WA to between coils 14WA and 14VA, so that the current with a frequency three times the rotational frequency FM of motor 14A circulates counterclockwise within the delta connection in FIG. 1. Furthermore, according to Kirchhoff's law, no current with a frequency three times the rotational frequency FM of motor 14A flows outside the delta connection formed by motor coils 14UA, 14VA, and 14WA.

[0037] Next, referring to Fig. 1, a description will be given of the current that flows through phase estimation device 200 when motor coil 14U, motor coil 14V, and motor coil 14W are unbalanced. Fig. 1 shows an example of the current that flows through phase estimation device 200 when motor coil 14U, motor coil 14V, and motor coil 14W are unbalanced. Fig. 1 describes a case where the number of parallel coils in motor coil 14W is one more than the number of parallel coils in motor coil 14U and the number of parallel coils in motor coil 14V.

[0038] If the number of parallel coils in motor coil 14W is greater than the number of parallel coils in motor coil 14U and the number of parallel coils in motor coil 14V, the impedance of motor coil 14U will decrease, and the current value of the current flowing through motor coil 14W at a frequency three times the rotational frequency FM of motor 14 will be greater than the current value of the current flowing through motor coil 14U at a frequency three times the rotational frequency FM of motor 14 and the current value of the current flowing through motor coil 14V at a frequency three times the rotational frequency FM of motor 14.

[0039] As a result, a current having a frequency three times the rotation frequency FM of motor 14 flows out from the coupling terminal between motor coils 14V and 14W, as shown by the dashed dotted line in Figure 1, and then flows into battery 11 via MOSFET 13L3.

[0040] The phase estimation unit 312 estimates the phase θ of the motor 14 based on the current value A1 of the current flowing through the motor coil 14V, the current value A2 of the current flowing through the motor coil 14U, and the current value A3 of the current flowing through the motor coil 14W.

[0041] [3. Configuration of the phase estimation device] Next, the configuration of the phase estimation device 200 will be described with reference to Fig. 2. Fig. 2 is a diagram showing an example of the configuration of the phase estimation device 200. As shown in FIG. 2, the phase estimation device 200 includes a control device 3.

[0042] The control device 3 is configured by, for example, an ECU (Electronic Control Unit), and includes a processor 31 such as a CPU (Central Processing Unit), and a memory 32 such as a ROM (Read Only Memory).

[0043] The memory 32 is a storage device that non-volatilely stores programs and data executed by the processor 31. The memory 32 is configured by a magnetic storage device, a semiconductor storage element such as a flash ROM, or other types of non-volatile storage device. The memory 32 may also include a RAM (Random Access Memory) that configures the work area of ​​the processor 31. The memory 32 stores data processed by the control device 3 and a control program 321 executed by the processor 31.

[0044] The processor 31 may be configured as a single processor, or a plurality of processors may function as the processor 31. The processor 31 executes a control program 321 to estimate the phase θ of the motor 14. The control device 3 includes an acquisition unit 311 and a phase estimation unit 312. Specifically, the processor 31 of the control device 3 executes a control program 321 to function as the acquisition unit 311 and the phase estimation unit 312. The control device 3 constitutes a "phase estimation device."

[0045] The acquisition unit 311 acquires the current value A1 of the motor coil 14V from the current sensor SA1. The acquisition unit 311 also acquires the current value A2 of the motor coil 14U from the current sensor SA2. The acquisition unit 311 also acquires the current value A3 of the motor coil 14W from the current sensor SA3. The acquisition unit 311 also acquires the voltage value V between the positive terminal 13P and the negative terminal 13N from the voltage sensor SV. The voltage value V is the value of the voltage applied to the motor 14.

[0046] The phase estimation unit 312 estimates the phase θ of the motor 14 based on the current value A1, the current value A2, the current value A3, and the voltage value V.

[0047] Next, the configuration of the control device 3 in the vehicle drive control device 100 according to this embodiment will be described with reference to Fig. 3. Fig. 3 is a diagram showing an example of the configuration of the control device 3. As shown in FIG. 3, the control device 3 includes a three-phase / two-phase converter 331, a current controller 332, a phase estimator 333, and a two-phase / three-phase converter 334. The phase estimator 333 constitutes a part of the phase estimation unit 312 .

[0048] The three-phase / two-phase converter 331 receives a three-phase current I' UVW3 is input. Three-phase current I' UVW3 is composed of current values ​​A1, A2, and A3. As described with reference to FIG. 1, the motor coils 14U, 14V, and 14W are unbalanced, so that the three-phase current I' UVW3 contains a current with a frequency three times the rotation frequency FM of the motor 14. The three-phase / two-phase converter 331 converts the three-phase current I' UVW3 γδ general coordinate system two-phase current I' γδ3 and convert it into two-phase current I' γδ3 The three-phase current I' is output. UVW3 contains a current with a frequency three times the rotation frequency FM of the motor 14, so the two-phase current I' γδ3 Also includes a current with a frequency three times the rotation frequency FM of the motor 14. The two-phase current I' output from the three-phase / two-phase converter 331 γδ3 is input to the phase estimator 333A. The phase estimator 333 calculates the two-phase current I' γδ3 Based on this, the phase θ of the motor 14A is estimated by synchronous detection processing and output.

[0049] The current controller 332 receives a torque command current I γδ and the two-phase current I' output from the three-phase / two-phase converter 331A. γδ3 The current controller 332A receives the difference between the torque command current Iγδ and two-phase current I' γδ3 From the difference between γδ Output. The two-phase / three-phase converter 334 receives the drive voltage command value V γδ The phase θ output from the phase estimator 333A is input to the two-phase / three-phase converter 334A. The two-phase / three-phase converter 334A calculates the drive voltage command value V γδ and the phase θ, the three-phase voltage command value V UVW is calculated and output to the motor driver 13 via the driver drive circuit 2A. In this way, in the control device 3 shown in FIG. 3, the three-phase voltage command value V UVW , the harmonic command voltage V γδh 8. The control device 3A differs from the control device 3A described with reference to FIG. 8 in that it does not include the above.

[0050] [4. Processing of the control device] Next, the processing of the control device 3 will be described with reference to Fig. 4. Fig. 4 is a flowchart showing an example of the processing of the control device 3. First, in step S101, the acquisition unit 311 acquires the voltage value V from the voltage sensor SV. The voltage value V is the value of the voltage applied to the motor 14. Next, in step S103, the acquisition unit 311 acquires current values ​​A1 to A3 of the currents flowing through the respective phases of the motor 14 from the current sensors SA1 to SA3.

[0051] Next, in step S105, the phase estimation unit 312 estimates the phase θ of the motor 14 based on the current value A1, the current value A2, the current value A3, and the voltage value V. Thereafter, the process returns to step S101.

[0052] [5.Motor coil deformation] Next, modified embodiments of the motor coils 14U to 14W that constitute the motor 14 will be described with reference to FIGS. Motor 14 is configured so that motor coil 14U, motor coil 14V, and motor coil 14W are unbalanced.

[0053] [5-1. First transformation form] FIG. 5 is a diagram showing a first modified embodiment of the motor coil 14U, the motor coil 14V, and the motor coil 14WB that constitute the motor 14B. In the motor 14 shown in FIG. 1, the number of parallel connections of the motor coil 14V is the same as the number of parallel connections of the motor coil 14U, and the number of parallel connections of the motor coil 14W is greater than the number of parallel connections of the motor coil 14U. In contrast, in the motor 14B shown in FIG. 5, the number of turns of the motor coil 14V is equal to the number of turns of the motor coil 14U, and the number of turns of the motor coil 14WB is greater than the number of turns of the motor coil 14U. The motor coil 14V corresponds to an example of a "second phase winding." The motor coil 14U corresponds to an example of a "first phase winding." The motor coil 14WB corresponds to an example of a "third phase winding."

[0054] As shown in FIG. 5, the number of parallel connections of each of the motor coils 14U, 14V, and 14WB is "4." 5, one of the four coils connected in parallel in motor coil 14WB has a greater number of turns than the other three coils. Note that the number of turns of each of the other three coils in motor coil 14WB matches the number of turns of each of the four coils connected in parallel in motor coil 14U and motor coil 14V.

[0055] 5 illustrates a case in which one of the four coils connected in parallel in motor coil 14WB has a greater number of turns than the other three coils, but the embodiment is not limited to this. The number of turns of motor coil 14WB may be greater than the number of turns of motor coil 14U and motor coil 14V. For example, in motor coil 14WB, two of the four coils connected in parallel may have more turns than the other two coils. Note that the number of turns of each of the other two coils in motor coil 14WB matches the number of turns of each of the four coils connected in parallel in motor coil 14U and motor coil 14V. Also, for example, in motor coil 14WB, three of the four coils connected in parallel may have more turns than the remaining coil. Note that the number of turns of the remaining coil in motor coil 14WB matches the number of turns of each of the four coils connected in parallel in motor coil 14U and motor coil 14V. Also, for example, in motor coil 14WB, the number of turns of each of the four coils connected in parallel may be greater than the number of turns of each of the four coils connected in parallel in each of motor coil 14U and motor coil 14V.

[0056] 5, when the number of turns of motor coil 14WB is greater than the number of turns of motor coil 14V and motor coil 14U, the impedance of motor coil 14WB is greater than the impedance of motor coil 14V and motor coil 14U. As a result, the current value of the current flowing through motor coil 14WB is smaller than the current value of the current flowing through motor coil 14V and motor coil 14U. Therefore, a current having a frequency three times the rotation frequency FM of the motor 14 flows out from the connecting terminal between the motor coil 14U and the motor coil 14WB or the connecting terminal between the motor coil 14V and the motor coil 14WB, and then flows into the battery 11 via the MOSFET 13L2 or the MOSFET 13L3.

[0057] [5-2. Second transformation form] FIG. 6 is a diagram showing a second modified embodiment of the motor coil 14U, the motor coil 14V, and the motor coil 14WC that constitute the motor 14C. In the motor 14 shown in FIG. 1, the number of parallel connections of the motor coil 14V is the same as the number of parallel connections of the motor coil 14U, and the number of parallel connections of the motor coil 14W is greater than the number of parallel connections of the motor coil 14U. In contrast to this, in a motor 14C shown in FIG. 6, a resistor 14R is arranged in series with a motor coil 14WA as a motor coil 14WC.

[0058] As shown in FIG. 6, the number of parallel connections of each of the motor coils 14U, 14V, and 14WA is "4." As shown in FIG. 6, the number of turns of each of the four coils connected in parallel in motor coil 14WA is the same as the number of turns of each of the four coils connected in parallel in motor coil 14U and motor coil 14V.

[0059] 6 illustrates a case where resistor 14R is arranged in series with motor coil 14WA, but the embodiment is not limited to this. It is sufficient to arrange a resistor in series with at least one of the four coils connected in parallel in motor coil 14WA. For example, in the motor coil 14WA, a resistor may be arranged in series with one of the four coils connected in parallel. Furthermore, for example, in the motor coil 14WA, of the four coils connected in parallel, a resistor may be arranged in series with each of two coils. Furthermore, for example, in the motor coil 14WA, of the four coils connected in parallel, resistors may be arranged in series with each of three coils.

[0060] 6, in motor 14C, when motor coil 14WC is configured by disposing resistor 14R in series with motor coil 14WA, the impedance between the connecting terminal between motor coils 14V and 14W and the connecting terminal between motor coils 14U and 14W, i.e., the impedance of motor coil 14WC, is greater than the impedance of each of motor coils 14V and 14U. As a result, the current value of the current flowing through motor coil 14WC, in other words, the current value of the current flowing through motor coil 14WA and resistor 14R, is smaller than the current value of the current flowing through motor coil 14V and motor coil 14U. Therefore, a current having a frequency three times the rotation frequency FM of the motor 14 flows out from the connecting terminal between the motor coil 14U and the motor coil 14WC or the connecting terminal between the motor coil 14V and the motor coil 14WC, and then flows into the battery 11 via the MOSFET 13L2.

[0061] [6. Composition and Effects] As described above, the phase estimation device 200 according to this embodiment includes a motor 14 in which motor coils 14U, 14V, and 14W are delta-connected, a battery 11 that supplies drive power to the motor 14, a motor driver 13 that converts DC power input from the battery 11 into AC power and supplies the AC power to each phase of the motor 14, and a phase estimation unit 312 that estimates the phase θ of the motor 14, wherein the motor coils 14U, 14V, and 14W are configured so that the impedance of at least one of the motor coils is different from the impedance of the motor coils of the other phases, and the phase estimation unit 312 estimates the phase θ of the motor 14 based on the current value A1 of the current flowing through the motor coil 14V, the current value A2 of the current flowing through the motor coil 14U, and the current value A3 of the current flowing through the motor coil 14W.

[0062] According to this configuration, there is no need to superimpose a high frequency voltage on the drive voltage of the motor 14, and therefore the drive voltage can be prevented from being limited.

[0063] Furthermore, in the phase estimation device 200, among the motor coils 14U, 14V, and 14W, the number of turns of the motor coil 14V matches the number of turns of the motor coil 14U, and the number of turns of the motor coil 14W is greater than the number of turns of the motor coil 14U.

[0064] This configuration allows motor coils 14U, 14V, and 14W to be configured to be unbalanced with a simple configuration. Furthermore, the smaller the difference between the number of turns of motor coil 14W and the number of turns of motor coil 14U, the more improved the driving efficiency of motor 14. Furthermore, the larger the difference between the number of turns of motor coil 14W and the number of turns of motor coil 14U, the more improved the estimation accuracy of phase θ.

[0065] Furthermore, in the phase estimation device 200, of the three-phase motor coils 14U, 14V, and 14W, the number of parallel connections of the motor coil 14V matches the number of parallel connections of the motor coil 14U, and the number of parallel connections of the motor coil 14W is greater than the number of parallel connections of the motor coil 14U.

[0066] This configuration allows the motor coils 14U, 14V, and 14W to be configured to be unbalanced with a simple configuration. Furthermore, the smaller the difference between the number of parallel connections of the motor coils 14W and the number of parallel connections of the motor coils 14U, the more the driving efficiency of the motor 14 can be improved. Furthermore, the larger the difference between the number of parallel connections of the motor coils 14W and the number of parallel connections of the motor coils 14U, the more the estimation accuracy of the phase θ can be improved.

[0067] Furthermore, in the phase estimation device 200, a resistor 14R is arranged in series with the motor coil 14W.

[0068] This configuration allows the motor coils 14U, 14V, and 14W to be unbalanced with a simple configuration. Furthermore, the smaller the resistance value of resistor 14R, the more improved the driving efficiency of motor 14. Furthermore, the larger the resistance value of resistor 14R, the more improved the estimation accuracy of phase θ.

[0069] The vehicle VC according to this embodiment comprises a motor 14 in which motor coils 14U, 14V, and 14W are delta-connected, a battery 11 that supplies drive power to the motor 14, a motor driver 13 that converts DC power input from the battery 11 into AC power and supplies the AC power to each phase of the motor 14, and a phase estimation unit 312 that estimates the phase θ of the motor 14, wherein the motor coils 14U, 14V, and 14W are configured so that the impedance of at least one of the motor coils is different from the impedance of the motor coils of the other phases, and the phase estimation unit 312 estimates the phase θ of the motor 14 based on a current value A1 of the current flowing through the motor coil 14V, a current value A2 of the current flowing through the motor coil 14U, and a current value A3 of the current flowing through the motor coil 14W.

[0070] This configuration provides the same effects as the phase estimation device 200 according to this embodiment.

[0071] 7. Other Embodiments The present invention is not limited to the configurations of the above-described embodiments, and can be implemented in various forms without departing from the spirit of the invention.

[0072] For example, in the above embodiment, the "switching element" is a MOSFET, but is not limited to this. The "switching element" may be, for example, a power transistor or an IGBT (Insulated Gate Bipolar Transistor).

[0073] At least some of the functional blocks shown in Figure 2 may be realized by hardware, or may be realized by a combination of hardware and software, and are not limited to a configuration in which independent hardware resources are arranged as shown in the figure. The control program 321 executed by the processor 31 of the control device 3 is stored in the memory 32, but the control program 321 may also be stored in an external HDD or the like.

[0074] The processing units in the flowchart shown in FIG. 4 are divided according to the main processing content to facilitate understanding of the processing of the control device 3 of the phase estimation device 200. The embodiment is not limited by the way in which the processing units are divided or the names of the processing units shown in the flowchart in FIG. 4. The processing of the control device 3 can be divided into more processing units depending on the processing content, or one processing unit can be divided so that it includes more processes. The processing order of the above flowchart is not limited to the example shown in the figure.

[0075] Each functional unit of the control device 3 can be realized by having the processor 31 execute a control program 321 corresponding to the control method of the control device 3. The control program 321 can be recorded on a computer-readable recording medium. The recording medium can be a magnetic or optical recording medium or a semiconductor memory device. Specifically, examples include portable or fixed recording media such as flexible disks, CD-ROMs (Compact Disk Read Only Memory), DVDs (Digital Versatile Discs), Blu-ray (registered trademark) Discs, magneto-optical disks, flash memories, and card-type recording media. The recording medium may be a non-volatile storage device such as a RAM, a ROM, or a HDD, which is an internal storage device provided in the control device 3. The control program 321 is stored in a server device or the like, and each functional unit of the control device 3 can be realized by downloading the control program 321 from the server device to the control device 3.

[0076] 8. Configurations Supported by the Above Embodiments The above embodiment supports the following configurations.

[0077] (Configuration 1) A phase estimation device comprising: a motor having three-phase windings delta-connected; a battery that supplies drive power to the motor; a drive circuit that converts DC power input from the battery into AC power and supplies the AC power to each phase of the motor; and a phase estimation unit that estimates the phase of the motor, wherein the three-phase windings are configured so that the impedance of at least one phase of the winding is different from the impedance of the other phases of the winding, and the phase estimation unit estimates the phase of the motor based on a current value that is included in a current flowing through each of the three-phase windings and corresponds to a harmonic of the rotational frequency of the motor.

[0078] The phase estimation device of configuration 1 detects current values ​​corresponding to harmonics of the motor's rotation frequency and estimates the motor phase based on the current values, eliminating the need for a sensor to detect the motor phase. Furthermore, since there is no need to superimpose high-frequency waves, limitations on the drive voltage can be suppressed.

[0079] (Configuration 2) The phase estimation device according to Configuration 1, wherein, of the three-phase windings, the number of turns of the second-phase winding is the same as the number of turns of the first-phase winding, and the number of turns of the third-phase winding is greater than the number of turns of the first-phase winding.

[0080] According to the phase estimation device of configuration 2, the three-phase windings can be configured to be unbalanced with a simple configuration. Furthermore, the greater the difference between the number of turns of the third-phase winding and the first-phase winding, the more accurate the phase estimation can be.

[0081] (Configuration 3) The phase estimation device according to Configuration 1, wherein, of the three-phase windings, the number of second-phase windings connected in parallel is equal to the number of first-phase windings connected in parallel, and the number of third-phase windings connected in parallel is greater than the number of first-phase windings connected in parallel. According to the phase estimation device of configuration 3, the three-phase windings can be configured to be unbalanced with a simple configuration. Furthermore, the greater the difference between the number of parallel connections of the third-phase windings and the number of parallel connections of the first-phase windings, the more accurate the estimation of the phase θ can be.

[0082] (Configuration 4) The phase estimation device according to any one of Configurations 1 to 3, wherein a resistor is arranged in series with one of the three-phase windings.

[0083] According to the phase estimation device of configuration 4, the three-phase windings can be configured to be unbalanced with a simple configuration. Furthermore, the greater the resistance value of the resistor, the more accurate the phase estimation can be.

[0084] (Configuration 5) A vehicle comprising: a motor having three-phase windings delta-connected; a battery that supplies drive power to the motor; a drive circuit that converts DC power input from the battery into AC power and supplies the AC power to each phase of the motor; and a phase estimation unit that estimates the phase of the motor, wherein the three-phase windings are configured so that the impedance of at least one phase of the winding is different from the impedance of the other phases of the winding, and the phase estimation unit estimates the phase of the motor based on a current value that is included in a current flowing through each of the three-phase windings and corresponds to a harmonic of the rotational frequency of the motor.

[0085] According to the vehicle of the fifth configuration, the same effects as those of the phase estimation device of the first configuration are achieved. [Explanation of symbols]

[0086] 100 Vehicle drive control device 200 Phase estimation device 1 Motor drive circuit 11 Battery 12 Capacitors 13 Motor driver (drive circuit) 13P positive terminal 13N negative terminal 13H1, 13H2, 13H3, 13L1, 13L2, 13L3 MOSFET 14, 14A, 14B, 14C motors 14U, 14V, 14W, 14WA, 14WB, 14WC motor coil (3-phase winding) 14R resistance 2 Driver drive circuit 3. Control device (phase estimation device) 31 processors 311 Acquisition Department 312 Phase estimation section 32 Memory 321 Control Program 331 3-phase / 2-phase converter 332 Phase estimator (part of the phase estimation section) 333 Current Controller 334 2-phase / 3-phase converter A1, A2, A3 current values SA1, SA2, SA3 Current Sensors SV voltage sensor V voltage value VC vehicle θ phase ω rotational angular velocity

Claims

1. A motor with three-phase windings in delta connection; a battery that supplies driving power to the motor; a drive circuit that converts DC power input from the battery into AC power and supplies the AC power to each phase of the motor; a phase estimation unit that estimates a phase of the motor; Equipped with the three-phase windings are configured so that the impedance of at least one phase winding is different from the impedance of the other phase windings, thereby creating an unbalanced state; the phase estimation unit estimates the phase of the motor based on a current value that is included in a current flowing through each of the three-phase windings and corresponds to a harmonic of a rotation frequency of the motor. Phase estimation device.

2. the number of turns of the second phase winding among the three phase windings is equal to the number of turns of the first phase winding; the number of turns of the third phase winding is greater than the number of turns of the first phase winding; The phase estimation device according to claim 1 .

3. the number of parallel windings of the second phase among the three phase windings is equal to the number of parallel windings of the first phase; the number of parallel windings of the third phase is greater than the number of parallel windings of the first phase; The phase estimation device according to claim 1 .

4. a resistor is disposed in series with one of the three-phase windings; The phase estimation device according to claim 1 .

5. A motor with three-phase windings delta-connected; a battery that supplies driving power to the motor; a drive circuit that converts DC power input from the battery into AC power and supplies the AC power to each phase of the motor; a phase estimation unit that estimates a phase of the motor; Equipped with the three-phase windings are configured so that the impedance of at least one phase winding is different from the impedance of the other phase windings, thereby creating an unbalanced state; the phase estimation unit estimates the phase of the motor based on a current value that is included in a current flowing through each of the three-phase windings and corresponds to a harmonic of a rotation frequency of the motor. vehicle.

Images