Electrical equipment

Abstract

To provide electrical equipment that can improve charging efficiency during AC charging. [Solution] The electrical equipment includes a power control unit that controls the power transfer between the energy storage device and the rotating electric machine, and an AC charging terminal that connects the power control unit to an external AC power source. The power control unit includes a first full-bridge circuit, a second full-bridge circuit, a first disconnector, a second disconnector, and a control device. The AC charging terminal is connected to both ends of the first and second disconnectors so that their magnetic fluxes cancel each other out when current supplied from an external AC power source flows through the first and second coils. During AC charging, when the energy storage device is charged by power supplied from an external AC power source, the control device controls the first and second disconnectors to be in an open state. When the charging torque generated during AC charging is greater than or equal to a predetermined value, the control device energizes both the first and second coils, and when the charging torque is less than a predetermined value, it energizes one of the first or second coils.

Description

Technical Field

[0001] The present invention relates to an electrical device.

Background Art

[0002] In recent years, research and development related to charging and power feeding in mobility equipped with secondary batteries that contribute to energy efficiency have been carried out, so as to ensure that more people can access affordable, reliable, sustainable and advanced energy.

[0003] Conventionally, for example, an electric vehicle is known that converts AC power supplied from an external power source into DC power by a combination of multi-phase stator windings of a motor and a multi-phase bridge circuit composed of switching elements (see, for example, Patent Document 1). In this electric vehicle, the current from the external power source is supplied to a connection point that divides the stator winding of each phase into two, so that the mutual magnetic fluxes in the magnetic circuit of the motor cancel each other out, and the generation of torque is suppressed.

Prior Art Documents

Patent Documents

[0004]

Patent Document 1

Summary of the Invention

Problems to be Solved by the Invention

[0005] Incidentally, in the technology for charging and supplying power to mobility devices equipped with secondary batteries, a challenge is to improve the charging efficiency of AC charging using an external power source. For example, in the case of the conventional electric vehicle described above, where multiple coils are provided in the divided stator windings of each phase to reduce the magnetic flux coupling between them and increase the effective inductance for ease of control, it may become difficult to increase the voltage boost ratio. If it is difficult to increase the voltage boost ratio when converting from AC power to DC power, other boosting operations will be required to secure the desired DC voltage, which may make it difficult to improve charging efficiency.

[0006] This invention aims to solve the above-mentioned problems by improving the charging efficiency during AC charging, and thereby contributing to energy efficiency. [Means for solving the problem]

[0007] To solve the above problems, the electrical equipment according to the present invention employs the following configuration.

[0008] (1): An electrical device according to one aspect of the present invention comprises: a power storage device; a rotating electric machine; a power control unit connected to the power storage device and the rotating electric machine for controlling the power transfer between the power storage device and the rotating electric machine; and an AC charging terminal for connecting the power control unit to an external AC power source, wherein the rotating electric machine comprises a first coil and a second coil, and the power control unit comprises: a first full-bridge circuit connected to both ends of the first coil; a second full-bridge circuit connected to both ends of the second coil; a first disconnector connected between one end of the first coil and the first full-bridge circuit; a second disconnector connected between one end of the second coil and the second full-bridge circuit; and the first coil The device comprises a control device for controlling the energization of the first coil and the second coil, wherein the AC charging terminals are connected to both ends of the first and second disconnectors such that when current supplied from the external AC power source flows through the magnetically coupled first and second coils, their magnetic fluxes cancel each other out. The control device controls the first and second disconnectors to a disconnected state during AC charging, in which the energy storage device is charged by power supplied from the external AC power source, and energizes both the first and second coils when the charging torque generated during AC charging is greater than or equal to a predetermined value, and energizes one of the first and second coils when the charging torque is less than the predetermined value.

[0009] (2) The electrical equipment according to the embodiment of (1) above further comprises a position sensor for detecting the rotor angle of the rotating electric machine, and the control device calculates the charging torque based on the rotor angle obtained from the output signal of the position sensor.

[0010] (3) In the embodiment of (1) above, in the rotating electric machine, the first coil and the second coil are wound in the same slot of the same phase, and the control device controls the direction of the current supplied from the external AC power supply so that when both the first coil and the second coil are energized, the magnetic fluxes of the first coil and the second coil cancel each other out.

[0011] (4): In any one embodiment of (1) to (3) above, the rotating electric machine comprises a third coil and a fourth coil whose phases are orthogonal to the first coil and the second coil, and the power control unit comprises a third full-bridge circuit connected to both ends of the third coil, a fourth full-bridge circuit connected to both ends of the fourth coil, a third disconnector connected between the positive terminals of the third full-bridge circuit and the fourth full-bridge circuit, and a fourth disconnector connected between the negative terminals of the third full-bridge circuit and the fourth full-bridge circuit.

[0012] (5) In the embodiment of (4) above, the third coil and the fourth coil are wound in the same slot in the rotating electric machine. [Effects of the Invention]

[0013] According to the embodiment of (1), when the charging torque during AC charging is greater than or equal to a predetermined value, both the first coil and the second coil are energized so that their magnetic fluxes cancel each other out, thereby suppressing vibrations in the charging torque generated in the rotating electric machine and increasing the voltage boosting rate due to the relatively small inductance. On the other hand, when the charging torque during AC charging is less than a predetermined value, the charging efficiency can be improved by energizing either the first coil or the second coil, while suppressing current ripple due to the relatively large inductance.

[0014] According to embodiment (2), the charging torque, which changes depending on the rotor angle, can be calculated with high accuracy, so the timing at which the charging torque exceeds a predetermined value can be detected with high accuracy.

[0015] According to embodiment (3), in a rotating electric machine, a structure is adopted in which the first coil and the second coil are wound in the same slot of the same phase, and both the first coil and the second coil are energized in such a way that their magnetic fields cancel each other out, thereby suppressing vibrations in the charging torque generated in the rotating electric machine and increasing the voltage boosting rate with a relatively small inductance.

[0016] (4) According to the aspect, when the rotating electric machine is driven by the power storage device, the power control unit can be caused to function as an inverter of a multiple full-bridge circuit. During AC charging of the power storage device by an external AC power supply, the combination of the third coil and the fourth coil with the third full-bridge circuit and the fourth full-bridge circuit can be caused to function as an insulated bidirectional DC-DC converter. For example, in the case of a boosting operation during AC charging, rapid charging can be performed for the voltage of the power storage device that is higher than the charging voltage from the external AC power supply.

[0017] (5) According to the aspect, by adopting a structure in which the third coil and the fourth coil are wound in the same slot in the rotating electric machine, the degree of magnetic coupling between the third coil and the fourth coil can be increased, so that the charging efficiency can be improved. [Brief Description of Drawings]

[0018] [Figure 1] It is a diagram showing a schematic configuration of an electric apparatus according to the present embodiment. [Figure 2] It is a diagram schematically showing a configuration of a rotating electric machine of the electric apparatus according to the present embodiment. [Figure 3] It is a block diagram showing a functional configuration of an electronic control unit of the electric apparatus according to the present embodiment. [Figure 4] It is a diagram showing a switching pattern of a second power conversion unit during two-coil driving. [Figure 5] It is a first timing chart showing the state of each element unit during two-coil driving. [Figure 6] It is a second timing chart showing the state of each element unit during two-coil driving. [Figure 7] It is a third timing chart showing the state of each element unit during two-coil driving. [Figure 8] It is a diagram showing the direction of magnetic flux generated in the rotating electric machine when the PWM control unit performs two-coil driving during AC charging. [Figure 9] It is a diagram showing a switching pattern of the second power conversion unit during single-coil driving. [Figure 10] This is a diagram showing the direction of magnetic flux generated in the rotating electric machine when the PWM control unit performs single-coil driving during AC charging. [Figure 11] This is a diagram showing the correspondence relationship between charging power and charging torque. [Figure 12] This is a flowchart showing a charging control process executed by the PWM control unit of the electrical device according to the present embodiment. [Figure 13] This is a diagram showing an example of the waveform of the current flowing through the β-phase first coil and the waveform of the current flowing through the β-phase second coil during single-coil driving. [Figure 14] This is a diagram showing an example of the waveform of the power supply current flowing during single-coil driving. [Figure 15] This is a diagram showing an example of the waveform of the current flowing through the β-phase first coil and the waveform of the current flowing through the β-phase second coil during two-coil driving. [Figure 16] This is a diagram showing an example of the waveform of the power supply current flowing during two-coil driving. [Mode for Carrying Out the Invention]

[0019] Hereinafter, one embodiment of the electrical device according to the present invention will be described with reference to the drawings.

[0020] FIG. 1 is a diagram showing a schematic configuration of an electrical device 10 according to the present embodiment. FIG. 2 is a diagram schematically showing the configuration of a rotating electric machine 16 of the electrical device 10. The electrical device 10 is mounted on, for example, electric vehicles, electric moving bodies, electric machines, and power supply devices. The electric vehicles are, for example, electric vehicles equipped with a rotating electric machine as a power source, saddle-type vehicles, kick scooters, hybrid vehicles using a combination of a rotating electric machine and an internal combustion engine, and fuel cell vehicles using a combination of a power storage device and a fuel cell. The electric moving bodies are, for example, robots, flying bodies, and water-surface and underwater moving bodies. The electric machines are, for example, construction machines equipped with a rotating electric machine as a power source. The power supply device is, for example, a stationary or mobile power supply device that performs discharging and charging of a power storage device.

[0021] (Electrical equipment) As shown in Figures 1 and 2, the electrical equipment 10 includes, for example, a power storage device 11, a first power conversion unit 12 and a second power conversion unit 13, a DC charging terminal 14 and an AC charging terminal 15, a rotating electric machine 16, a gate drive unit 17, an electronic control unit 18, and a position sensor 19. For example, the first power conversion unit 12, the second power conversion unit 13, the DC charging terminal 14, the AC charging terminal 15, the gate drive unit 17, and the electronic control unit 18 constitute a power control unit 10a.

[0022] The energy storage device 11 is connected to the first power conversion unit 12 and the second power conversion unit 13, which will be described later. The energy storage device 11 comprises, for example, a plurality of battery cells connected in series or in parallel. Each battery cell is, for example, a secondary battery such as a lead-acid battery, lithium-ion battery, nickel-metal hydride battery, and all-solid-state battery, a capacitor such as an electric double-layer capacitor, or a composite battery consisting of a secondary battery and a capacitor. Each battery cell undergoes repeated charging and discharging. The energy storage device 11 exchanges power with the rotating electric machine 16 via the power control unit 10a. The energy storage device 11 is charged by an external power source (external DC power source and external AC power source).

[0023] The first power conversion unit 12 includes a first full-bridge circuit 12a and a second full-bridge circuit 12b. Each of the first full-bridge circuit 12a and the second full-bridge circuit 12b includes a so-called H-bridge circuit formed by a plurality of switching elements connected in a two-phase bridge configuration, for example. Each switching element included in the first full-bridge circuit 12a and the second full-bridge circuit 12b is, for example, a MOSFET (Metal Oxide Semiconductor Field Effect Transistor) made of SiC (Silicon Carbide) or a transistor such as an IGBT (Insulated Gate Bipolar Transistor). Each switching element included in the first full-bridge circuit 12a and the second full-bridge circuit 12b is, for example, an N-channel type MOSFET.

[0024] The multiple switching elements included in the first full-bridge circuit 12a and the second full-bridge circuit 12b are, for example, pairs of transistors that form the high-side arm and low-side arm element sections 21a and 21b, respectively, which form a pair in each phase. Each pair of transistors in each element section 21a and 21b is connected in parallel, for example. Each full-bridge circuit 12a and 12b may also include rectifier elements such as freewheeling diodes that are connected in parallel in the forward direction from emitter to collector between the collector and emitter of each transistor.

[0025] The first power conversion unit 12 includes, for example, a first switch 22 connected between the second midpoint of the first full-bridge circuit 12a and the third midpoint of the second full-bridge circuit 12b. The second midpoint of the first full-bridge circuit 12a is, for example, the connection point between the high-side arm element section 21a(a2H) and the low-side arm element section 21b(a2L), which are connected in series in the second phase of the two phases of the first full-bridge circuit 12a. For example, the second midpoint of the first full-bridge circuit 12a is the connection point between the source of the high-side arm element section 21a(a2H) and the drain of the low-side arm element section 21b(a2L).

[0026] The third midpoint of the second full-bridge circuit 12b is, for example, the connection point between the high-side arm element section 21a(a3H) and the low-side arm element section 21b(a3L), which are connected in series in the first phase of the two-phase second phase of the second full-bridge circuit 12b. For example, the third midpoint of the second full-bridge circuit 12b is the connection point between the source of the high-side arm element section 21a(a3H) and the drain of the low-side arm element section 21b(a3L).

[0027] The first switch 22 is, for example, a bidirectional switch formed by two switching elements. Each switching element included in the first switch 22 is a transistor such as a MOSFET or IGBT, for example, an N-channel MOSFET. The first switch 22 comprises, for example, two transistors connected in reverse series. The two transistors are connected in series in opposite directions to each other, for example, by connecting their sources to each other. The first switch 22 switches the conduction and interruption of current between the second midpoint of the first full-bridge circuit 12a and the third midpoint of the second full-bridge circuit 12b by turning the two transistors on (conducting) and off (blocking). Each transistor included in the first switch 22 may be equipped with a rectifier element such as a freewheeling diode connected in parallel in the forward direction from the emitter to the collector between the collector and emitter.

[0028] The first power conversion unit 12 is connected to the α-phase first coil 23 (α1) and the α-phase second coil 24 (α2) of the rotating electric machine 16, which will be described later. The α-phase first coil 23 (α1) is connected between the first midpoint and the second midpoint in the first full-bridge circuit 12a. The first midpoint of the first full-bridge circuit 12a is, for example, the connection point between the element section 21a (a1H) of the high-side arm and the element section 21b (a1L) of the low-side arm, which are connected in series in the first phase of the first full-bridge circuit 12a. For example, the first midpoint of the first full-bridge circuit 12a is the connection point between the source of the element section 21a (a1H) of the high-side arm and the drain of the element section 21b (a1L) of the low-side arm.

[0029] The α-phase second coil 24(α2) is connected between the third midpoint and the fourth midpoint in the second full-bridge circuit 12b. The fourth midpoint of the second full-bridge circuit 12b is, for example, the connection point between the high-side arm element section 21a(a4H) and the low-side arm element section 21b(a4L), which are connected in series in the second phase of the second full-bridge circuit 12b. For example, the fourth midpoint of the second full-bridge circuit 12b is the connection point between the source of the high-side arm element section 21a(a4H) and the drain of the low-side arm element section 21b(a4L).

[0030] The first power conversion unit 12 includes a first disconnector 25 connected between the positive terminals of the first full-bridge circuit 12a and the second full-bridge circuit 12b, and a second disconnector 26 connected between the negative terminals of the first full-bridge circuit 12a and the second full-bridge circuit 12b. Each of the first disconnector 25 and the second disconnector 26 is, for example, a contactor that switches the connection between the first full-bridge circuit 12a and the second full-bridge circuit 12b on and off.

[0031] The first power conversion unit 12 includes, for example, a first capacitor 27 connected between the positive and negative electrodes. The first capacitor 27 smooths out voltage fluctuations that occur due to the on and off switching operation of each switching element of the first power conversion unit 12.

[0032] The first power conversion unit 12 includes a first current sensor 28a, a second current sensor 28b, and a third current sensor 28c. For example, the first current sensor 28a is positioned between the α-phase first coil 23 (α1) and the second midpoint of the first full-bridge circuit 12a. The second current sensor 28b is positioned between the α-phase second coil 24 (α2) and the fourth midpoint of the second full-bridge circuit 12b. The third current sensor 28c is positioned between the energy storage device 11 and the first power conversion unit 12.

[0033] For example, the first current sensor 28a detects the current flowing through the α-phase first coil 23 (α1). The second current sensor 28b detects the current flowing through the α-phase second coil 24 (α2). The third current sensor 28c detects the current flowing between the first power conversion unit 12 and the energy storage device 11.

[0034] The second power conversion unit 13 includes a third full-bridge circuit 13a and a fourth full-bridge circuit 13b. Each of the third full-bridge circuit 13a and the fourth full-bridge circuit 13b includes a so-called H-bridge circuit formed by a plurality of switching elements connected in a two-phase bridge configuration, for example. Each switching element included in the third full-bridge circuit 13a and the fourth full-bridge circuit 13b is, for example, a MOSFET such as a SiC or a transistor such as an IGBT. Each switching element included in the third full-bridge circuit 13a and the fourth full-bridge circuit 13b is, for example, an N-channel type MOSFET.

[0035] The multiple switching elements included in the third full-bridge circuit 13a and the fourth full-bridge circuit 13b are, for example, pairs of transistors that form the high-side arm and low-side arm element sections 31a and 31b, respectively, which form a pair in each phase. Each pair of transistors in each element section 31a and 31b is connected in parallel, for example. Each full-bridge circuit 13a, 13b may also include a rectifier element such as a freewheeling diode connected in parallel in the forward direction from the emitter to the collector between the collector and emitter of each transistor.

[0036] The second power conversion unit 13 includes, for example, a second switch 32 connected between the sixth midpoint of the third full-bridge circuit 13a and the seventh midpoint of the fourth full-bridge circuit 13b. The sixth midpoint of the third full-bridge circuit 13a is, for example, the connection point between the high-side arm element section 31a(b2H) and the low-side arm element section 31b(b2L), which are connected in series in the second phase of the two-phase third full-bridge circuit 13a. For example, the sixth midpoint of the third full-bridge circuit 13a is the connection point between the source of the high-side arm element section 31a(b2H) and the drain of the low-side arm element section 31b(b2L).

[0037] The seventh midpoint of the fourth full-bridge circuit 13b is, for example, the connection point between the high-side arm element section 31a(b3H) and the low-side arm element section 31b(b3L), which are connected in series in the first phase of the two-phase fourth full-bridge circuit 13b. For example, the seventh midpoint of the fourth full-bridge circuit 13b is the connection point between the source of the high-side arm element section 31a(b3H) and the drain of the low-side arm element section 31b(b3L).

[0038] The second switch 32 is, for example, a bidirectional switch formed by two switching elements. Each switching element in the second switch 32 is a transistor such as a MOSFET or IGBT, for example, an N-channel MOSFET. The second switch 32 comprises, for example, two transistors connected in reverse series. The two transistors are connected in series in opposite directions to each other, for example, by connecting their sources to each other. The second switch 32 switches the conduction and interruption of current between the sixth midpoint of the third full-bridge circuit 13a and the seventh midpoint of the fourth full-bridge circuit 13b by switching the two transistors on and off. Each transistor included in the second switch 32 may be equipped with a rectifier element such as a freewheeling diode connected in parallel in the forward direction from the emitter to the collector between the collector and emitter.

[0039] The second power conversion unit 13 is connected to the β-phase first coil 33 (β1) and the β-phase second coil 34 (β2) of the rotating electric machine 16, which will be described later. The β-phase first coil 33 is connected between the fifth midpoint and the sixth midpoint in the third full-bridge circuit 13a. The fifth midpoint of the third full-bridge circuit 13a is, for example, the connection point between the element section 31a (b1H) of the high-side arm and the element section 31b (b1L) of the low-side arm, which are connected in series in the first phase of the third full-bridge circuit 13a. For example, the fifth midpoint of the third full-bridge circuit 13a is the connection point between the source of the element section 31a (b1H) of the high-side arm and the drain of the element section 31b (b1L) of the low-side arm.

[0040] The β-phase second coil 34(β2) is connected between the 7th midpoint and the 8th midpoint in the fourth full-bridge circuit 13b. The 8th midpoint of the fourth full-bridge circuit 13b is, for example, the connection point between the high-side arm element section 31a(b4H) and the low-side arm element section 31b(b4L), which are connected in series in the second phase of the fourth full-bridge circuit 13b. For example, the 4th midpoint of the fourth full-bridge circuit 13b is the connection point between the source of the high-side arm element section 31a(b4H) and the drain of the low-side arm element section 31b(b4L).

[0041] The second power conversion unit 13 includes a third disconnector 35 and a fourth disconnector 36. The third disconnector 35 is connected between the β-phase first coil 33 (β1) and the fifth midpoint of the third full-bridge circuit 13a. The fourth disconnector 36 is connected between the β-phase second coil 34 (β2) and the eighth midpoint of the fourth full-bridge circuit 13b. Each of the third disconnector 35 and the fourth disconnector 36 is, for example, a contactor. The third disconnector 35 switches the connection between the β-phase first coil 33 (β1) and the fifth midpoint of the third full-bridge circuit 13a on and off. The fourth disconnector 36 switches the connection between the β-phase second coil 34 (β2) and the eighth midpoint of the fourth full-bridge circuit 13b on and off.

[0042] The second power conversion unit 13 includes, for example, a second capacitor 37 connected between the positive and negative electrodes. The second capacitor 37 smooths out voltage fluctuations that occur due to the on and off switching operation of each switching element of the second power conversion unit 13.

[0043] The second power conversion unit 13 includes a fourth current sensor 38a and a fifth current sensor 38b. The fourth current sensor 38a is positioned between the β-phase first coil 33 (β1) and the sixth midpoint of the third full-bridge circuit 13a. The fifth current sensor 38b is positioned between the β-phase second coil 34 (β2) and the eighth midpoint of the fourth full-bridge circuit 13b. For example, the fourth current sensor 38a detects the current flowing through the β-phase first coil 33 (β1). The fifth current sensor 38b detects the current flowing through the β-phase second coil 34 (β2).

[0044] The DC charging terminal 14 and AC charging terminal 15 are equipped with, for example, connectors for DC and AC power conforming to predetermined standards. The DC charging terminal 14 and AC charging terminal 15 are connected to an external DC power source (external DC power source) and an AC power source (external AC power source) based, for example, a commercial power source connected to a power grid.

[0045] The DC charging terminal 14 is connected to the negative terminal of the second power conversion unit 13 and to the midpoints of the first switch 22 and the second switch 32 (i.e., between the two transistors connected in reverse series). The AC charging terminal 15 is connected to the fifth midpoint of the third full-bridge circuit 13a and the eighth midpoint of the fourth full-bridge circuit 13b. The AC charging terminal 15 is also connected to the connection point between the β-phase first coil 33 (β1) and the third disconnector 35, and to the connection point between the β-phase second coil 34 (β2) and the fourth disconnector 36.

[0046] The rotating electric machine 16 is, for example, a two-phase AC brushless DC motor. As shown in Figure 2, the rotating electric machine 16 includes, for example, an α-phase first coil 23 (α1) and an α-phase second coil 24 (α2), a β-phase first coil 33 (β1) and a β-phase second coil 34 (β2), a rotor 41, and a stator core 42. The rotor 41 is equipped with permanent magnets for the field. The stator core 42 is fitted with the coils α1, α2, β1, and β2 that generate a rotating magnetic field to rotate the rotor 41.

[0047] The α-phase first coil 23 (α1) and the α-phase second coil 24 (α2), and the β-phase first coil 33 (β1) and the β-phase second coil 34 (β2) are so-called open-ended coils, and the ends of each coil α1, α2, β1, and β2 are not connected to each other (that is, each coil α1, α2, β1, and β2 are disconnected from each other) and are led out to the outside of the rotating electric machine 16.

[0048] The α-phase first coil 23 (α1) and the α-phase second coil 24 (α2) are, for example, made to have zero spatial phase difference with respect to each other and are wound around the teeth of the stator core 42 in the same direction when viewed from the axial direction along the central axis O of the rotating electric machine 16. The α-phase first coil 23 (α1) and the α-phase second coil 24 (α2) are arranged, for example, to share or each occupy a part of the slot 43 formed in the stator core 42, and are magnetically coupled to each other with the same polarity.

[0049] The β-phase first coil 33 (β1) and the β-phase second coil 34 (β2) are, for example, made to have zero spatial phase difference with respect to each other, and are wound around the teeth of the stator core 42 in the same direction when viewed from the axial direction along the central axis O of the rotating electric machine 16. The β-phase first coil 33 (β1) and the β-phase second coil 34 (β2) are arranged, for example, to share or each occupy a part of the slot 43 formed in the stator core 42, and are magnetically coupled to each other with the same polarity.

[0050] The α-phase first coil 23 (α1) and the α-phase second coil 24 (α2), and the β-phase first coil 33 (β1) and the β-phase second coil 34 (β2) are arranged so as not to interfere with each other magnetically by setting a spatial phase difference of 90° between them. For example, each coil α1, α2, β1, and β2 is mounted on the stator core 42 by concentrated winding or distributed winding, etc.

[0051] For example, in the rotating electric machine 16, the β-phase first coil 33 (β1) and the β-phase second coil 34 (β2) are wound in the same slot 43 of the same phase, and the α-phase first coil 23 (α1) and the α-phase second coil 24 (α2) are wound in the same slot 43. Specifically, the β-phase first coil 33 (β1) and the β-phase second coil 34 (β2) are wound in the first slot SL1 and the second slot SL2, as well as in the third slot SL3 and the fourth slot SL4. The α-phase first coil 23 (α1) and the α-phase second coil 24 (α2) are wound in the first slot SL1 and the fourth slot SL4, as well as in the second slot SL2 and the third slot SL3.

[0052] The rotating electric machine 16 generates rotational power by performing a motoring operation using power supplied from the first power conversion unit 12 and the second power conversion unit 13. When the rotating electric machine 16 is connected to the wheels of a vehicle, for example, it generates driving force using power supplied from the first power conversion unit 12 and the second power conversion unit 13. The rotating electric machine 16 may also generate electricity by performing a regenerative operation using rotational power input from the wheels of the vehicle. When the rotating electric machine 16 is connected to the internal combustion engine of a vehicle, for example, it may generate electricity using the power of the internal combustion engine.

[0053] The gate drive unit 17 switches the switching elements of the first power conversion unit 12 and the second power conversion unit 13, as well as the disconnectors 25, 26, 35, and 36, on and off based on the control signals received from the electronic control unit 18. For example, the gate drive unit 17 switches the switching elements of each full-bridge circuit 12a, 12b, 13a, and 13b on and off by outputting a gate signal generated by amplifying and level-shifting the control signal.

[0054] The position sensor 19 detects the rotation angle of the rotor 41 of the rotating electric machine 16 as the rotor angle θ, and outputs an analog signal indicating the detected rotor angle θ to the electronic control unit 18. For example, the position sensor 19 is a resolver attached to the rotor shaft (not shown) of the rotating electric machine 16.

[0055] The electronic control unit 18 integrally controls the operation of the power control unit 10a and the rotating electric machine 16. For example, the electronic control unit 18 is a software function unit that functions when a predetermined program is executed by a processor such as a CPU (Central Processing Unit). The software function unit is an ECU (Electronic Control Unit) equipped with a processor such as a CPU, a ROM (Read Only Memory) for storing programs, a RAM (Random Access Memory) for temporarily storing data, and electronic circuits such as timers. At least a part of the electronic control unit 18 may be an integrated circuit such as an LSI (Large Scale Integration).

[0056] The electronic control unit 18 generates control signals that indicate the timing for turning on and off the switching elements and disconnectors 25, 26, 35, and 36 of the first power conversion unit 12 and the second power conversion unit 13. The electronic control unit 18 outputs the generated control signals to the gate drive unit 17.

[0057] (Control operation of electrical equipment) The electronic control unit 18 sets the first disconnector 25 and the second disconnector 26 to the ON state when the rotating electric machine 16 is in powering or regenerative operation. The electronic control unit 18 switches between the series connection of each α-phase coil α1, α2 and each β-phase coil β1, β2, and the parallel connection of each α-phase coil α1, α2 and each β-phase coil β1, β2 by switching the first switch 22 and the second switch 32 on and off.

[0058] The electronic control unit 18 performs current feedback control, for example, using the current detection value of the rotating electric machine 16 and the current target value corresponding to the torque command value of the rotating electric machine 16, and generates control signals that instruct the driving of the switching elements of the first power conversion unit 12 and the second power conversion unit 13.

[0059] When charging with DC power, that is, when charging the energy storage device 11 with an external DC power supply connected to the DC charging terminal 14, the electronic control unit 18 sets the first disconnector 25 and the second disconnector 26 to the ON state. For example, the electronic control unit 18 makes each combination of the α-phase coils α1, α2 and the first power conversion unit 12, and each combination of the β-phase coils β1, β2 and the second power conversion unit 13, function as a non-isolated DC-DC converter that performs a boost operation by so-called chopper control for an external DC power supply with a voltage lower than that of the energy storage device 11.

[0060] When AC charging occurs, that is, when the energy storage device 11 is charged by an external AC power source connected to the AC charging terminal 15, the electronic control unit 18 sets the first disconnector 25 and the second disconnector 26 to the OFF state for insulation.

[0061] The electronic control unit 18 uses, for example, the α-phase first coil 23 (α1) and the α-phase second coil 24 (α2), which are magnetically coupled to each other with the same polarity, as coils for the DC conversion phase (α-phase) used for converting DC power. The electronic control unit 18 makes, for example, the combination of each α-phase coil α1, α2 and the first power conversion unit 12 function as a DAB (Dual Active Bridge) type DC-DC converter, which is an isolated bidirectional (boost and buck) converter.

[0062] The electronic control unit 18 uses, for example, a first β-phase coil 33 (β1) and a second β-phase coil 34 (β2), which are magnetically coupled to each other with the same polarity, as coils for the AC input phase (β-phase) connected to an external AC power source. The electronic control unit 18 uses, for example, the combination of each β-phase coil β1, β2 and the second power conversion unit 13 to function as a so-called full-bridgeless (or bridgeless and totem-pole) power factor correction (PFC) circuit that converts AC power to DC power. A so-called bridgeless PFC is a PFC that does not have a bridge rectifier made of multiple diodes connected in a bridge configuration, and a so-called totem-pole PFC is a PFC that has a pair of switching elements of the same conductivity connected in series in the same direction (totem-pole connection). The electronic control unit 18, for example, controls the switching of each switching element in each full-bridge circuit 13a, 13b of the second power conversion unit 13, thereby rectifying and boosting the AC power received from the external AC power source to DC power, while also improving the power factor of the input voltage Vac and input current Iac.

[0063] Figure 3 is a block diagram showing the functional configuration of the electronic control unit 18 during AC charging of the electrical equipment 10. As shown in Figure 3, the second power conversion unit 13 includes, for example, an input voltage sensor 51 that detects the input voltage Vac of the external AC power supply and an input current sensor 52 that detects the input current Iac of the external AC power supply.

[0064] In Figure 3, the symbol R1 indicates the fifth midpoint of the third full-bridge circuit 13a, and the symbol R2 indicates the sixth midpoint of the third full-bridge circuit 13a. Also in Figure 3, the symbol R3 indicates the seventh midpoint of the fourth full-bridge circuit 13b, and the symbol R4 indicates the eighth midpoint of the fourth full-bridge circuit 13b.

[0065] The electronic control unit 18 includes, for example, a power supply voltage acquisition unit 61, a power supply current acquisition unit 62, a phase calculation unit 63, a target current calculation unit 64, a current control unit 65, a power calculation unit 66, a PWM (Pulse Width Modulation) control unit 67, and a rotor angle acquisition unit 68.

[0066] The power supply voltage acquisition unit 61 outputs an input voltage Vac acquired from, for example, the input voltage sensor 51. The power supply current acquisition unit 62 outputs an input current Iac acquired from, for example, the input current sensor 53. The phase calculation unit 63 calculates the phase of the input voltage Vac output from the power supply voltage acquisition unit 61. The target current calculation unit 64 calculates a target current synchronized with the input voltage Vac based on, for example, the target current amplitude with respect to the input current Iac and the phase of the input voltage Vac output from the phase calculation unit 63.

[0067] The current control unit 65 outputs the duty cycle of the voltage command by means of PI (proportional-integral) control, for example, based on the current deviation obtained by subtracting the target current output from the target current calculation unit 64 and the input current Iac output from the power supply current acquisition unit 62. The duty cycle of the voltage command defines the ratio of the on time to the switching period of the switching elements (i.e., the high-side arm and low-side arm switching elements of each phase) in each phase of the full-bridge circuits 13a and 13b of the second power conversion unit 13. In the following description, the duty cycle of the voltage command may be referred to as the duty command value.

[0068] The power calculation unit 66 outputs power obtained by multiplying, for example, the input voltage Vac output from the power supply voltage acquisition unit 61 and the input current Iac output from the power supply current acquisition unit 62. The rotor angle acquisition unit 68 outputs a digital signal indicating the rotor angle θ (electrical angle) by converting the analog signal output from the position sensor 19 into a digital signal. For example, the rotor angle acquisition unit 68 is an R / D converter.

[0069] The PWM control unit 67 generates control signals that indicate the timing for turning on and off each element b1H, b1L, b2H, b2L, b3H, b3L, b4H, and b4L included in the second power conversion unit 13 by performing pulse width modulation based on the duty cycle command value and the carrier wave CW. For example, the carrier wave CW is a triangular wave.

[0070] The operation of the PWM control unit 67 during AC charging will be described in detail below. During AC charging, the third disconnector 35 and the fourth disconnector 36 included in the second power conversion unit 13 are controlled to the off state (disconnected state) by the electronic control unit 18.

[0071] During AC charging, the PWM control unit 67 charges the energy storage device 11 by switching between two-coil drive and one-coil drive according to the charging torque. Two-coil drive means energizing both the β-phase first coil 33 (β1) and the β-phase second coil 34 (β2). One-coil drive means energizing either the β-phase first coil 33 (β1) or the β-phase second coil 34 (β2). For example, in one-coil drive mode, the PWM control unit 67 energizes the β-phase first coil 33 (β1).

[0072] Figure 4 shows the switching pattern of the second power conversion unit 13 when two coils are driven. In the first mode, the elements b1H, b2H, b3H, and b4H of the high-side arm are in the ON state, and the elements b1L, b2L, b3L, and b4L of the low-side arm are in the OFF state. In this first mode, alternating current flows through both the β-phase first coil 33 (β1) and the β-phase second coil 34 (β2), and both the β-phase first coil 33 (β1) and the β-phase second coil 34 (β2) are charged. Here, "charging" means that magnetic energy generated by the flow of alternating current through each coil is stored in each coil.

[0073] In the second mode, elements b1H and b4H of the high-side arm are in the ON state, elements b2H and b3H of the high-side arm are in the OFF state, elements b1L and b4L of the low-side arm are in the OFF state, and elements b2L and b3L of the low-side arm are in the ON state. In this second mode, both the β-phase first coil 33 (β1) and the β-phase second coil 34 (β2) discharge. Here, "discharge" means that the magnetic energy stored in each coil is released as electrical energy (current).

[0074] In the third mode, the elements b1H and b4H of the high-side arm are in the off state, the elements b2H and b3H of the high-side arm are in the on state, the elements b1L and b4L of the low-side arm are in the on state, and the elements b2L and b3L of the low-side arm are in the off state. In this third mode, both the β-phase first coil 33 (β1) and the β-phase second coil 34 (β2) discharge.

[0075] In the fourth mode, the elements b1H, b2H, b3H, and b4H of the high-side arm are in the off state, while the elements b1L, b2L, b3L, and b4L of the low-side arm are in the on state. In this fourth mode, alternating current flows through both the β-phase first coil 33 (β1) and the β-phase second coil 34 (β2), and both the β-phase first coil 33 (β1) and the β-phase second coil 34 (β2) are charged.

[0076] Figure 5 is a first timing chart showing the state of each element when two coils are driven. In Figure 5, the period from time t1 to time t6 and the period from time t6 to time t11 correspond to one period Tc of the carrier wave CW. As shown in Figure 5, the duty cycle command value includes a first duty cycle command value D1 and a second duty cycle command value D2. Figure 5 shows the case where the first duty cycle command value D1 is greater than or equal to 0 and less than 0.5. The second duty cycle command value D2 is obtained by subtracting the first duty cycle command value D1 from 1.

[0077] When two coils are driven, the PWM control unit 67 compares the magnitude of the first duty cycle command value D1 with the carrier wave CW, and generates a control signal such that if the first duty cycle command value D1 is less than the value of the carrier wave CW, the elements b2H and b3H of the high-side arm are turned off, and the elements b2L and b3L of the low-side arm are turned on. Also when two coils are driven, the PWM control unit 67 generates a control signal such that if the first duty cycle command value D1 is greater than or equal to the value of the carrier wave CW, the elements b2H and b3H of the high-side arm are turned on, and the elements b2L and b3L of the low-side arm are turned off.

[0078] When two coils are driven, the PWM control unit 67 compares the second duty cycle command value D2 with the carrier wave CW value and generates a control signal such that if the second duty cycle command value D2 is less than the carrier wave CW value, the elements b1H and b4H of the high-side arm are turned off, and the elements b1L and b4L of the low-side arm are turned on. Also when two coils are driven, the PWM control unit 67 generates a control signal such that if the second duty cycle command value D2 is greater than or equal to the carrier wave CW value, the elements b1H and b4H of the high-side arm are turned on, and the elements b1L and b4L of the low-side arm are turned off.

[0079] As a result, when two coils are driven and the first duty cycle command value D1 is greater than or equal to 0 and less than 0.5, during the period from time t1 to time t2, both the β-phase first coil 33 (β1) and the β-phase second coil 34 (β2) are charged by the fourth mode switching pattern. During the period from time t2 to time t3, both the β-phase first coil 33 (β1) and the β-phase second coil 34 (β2) are discharged by the third mode switching pattern. During the period from time t3 to time t4, both the β-phase first coil 33 (β1) and the β-phase second coil 34 (β2) are charged by the first mode switching pattern. During the period from time t4 to time t5, both the β-phase first coil 33 (β1) and the β-phase second coil 34 (β2) are discharged by the third mode switching pattern. During the period from time t5 to time t6, both the β-phase first coil 33 (β1) and the β-phase second coil 34 (β2) are charged by the fourth mode switching pattern.

[0080] Similarly, when two coils are driven and the first duty cycle command value D1 is greater than or equal to 0 and less than 0.5, during the period from time t6 to time t7, both the β-phase first coil 33 (β1) and the β-phase second coil 34 (β2) are charged by the fourth mode switching pattern. During the period from time t7 to time t8, both the β-phase first coil 33 (β1) and the β-phase second coil 34 (β2) are discharged by the third mode switching pattern. During the period from time t8 to time t8, both the β-phase first coil 33 (β1) and the β-phase second coil 34 (β2) are charged by the first mode switching pattern. During the period from time t9 to time t10, both the β-phase first coil 33 (β1) and the β-phase second coil 34 (β2) are discharged by the third mode switching pattern. During the period from time t10 to time t11, both the β-phase first coil 33 (β1) and the β-phase second coil 34 (β2) are charged by the switching pattern of the fourth mode.

[0081] Figure 6 is a second timing chart showing the state of each element when two coils are driven. In Figure 6, the period from time t21 to time t24 and the period from time t24 to time t27 correspond to one period Tc of the carrier wave CW. Figure 6 shows the case where the first duty cycle command value D1 is 0.5. In other words, the second duty cycle command value D2 is also 0.5.

[0082] As shown in Figure 6, when the first duty cycle command value D1 is 0.5 while two coils are driven, during the period from time t21 to time t22, both the β-phase first coil 33 (β1) and the β-phase second coil 34 (β2) are charged by the fourth mode switching pattern. During the period from time t22 to time t23, both the β-phase first coil 33 (β1) and the β-phase second coil 34 (β2) are charged by the first mode switching pattern. During the period from time t23 to time t24, both the β-phase first coil 33 (β1) and the β-phase second coil 34 (β2) are charged by the fourth mode switching pattern.

[0083] Similarly, when the first duty cycle command value D1 is 0.5 while two coils are driven, during the period from time t24 to time t25, both the β-phase first coil 33 (β1) and the β-phase second coil 34 (β2) are charged by the fourth mode switching pattern. During the period from time t25 to time t26, both the β-phase first coil 33 (β1) and the β-phase second coil 34 (β2) are charged by the first mode switching pattern. During the period from time t26 to time t27, both the β-phase first coil 33 (β1) and the β-phase second coil 34 (β2) are charged by the fourth mode switching pattern.

[0084] Figure 7 is a third timing chart showing the state of each element when two coils are driven. In Figure 7, the period from time t31 to time t36 and the period from time t36 to time t41 correspond to one period Tc of the carrier wave CW. Figure 7 shows the case where the first duty command value D1 is 1 or less and greater than 0.5.

[0085] As shown in Figure 7, when two coils are driven and the first duty cycle command value D1 is 1 or less and greater than 0.5, during the period from time t31 to time t32, both the β-phase first coil 33 (β1) and the β-phase second coil 34 (β2) are charged by the fourth mode switching pattern. During the period from time t32 to time t33, both the β-phase first coil 33 (β1) and the β-phase second coil 34 (β2) are discharged by the second mode switching pattern. During the period from time t33 to time t34, both the β-phase first coil 33 (β1) and the β-phase second coil 34 (β2) are charged by the first mode switching pattern. During the period from time t34 to time t25, both the β-phase first coil 33 (β1) and the β-phase second coil 34 (β2) are discharged by the second mode switching pattern. During the period from time t35 to time t36, both the β-phase first coil 33 (β1) and the β-phase second coil 34 (β2) are charged by the fourth mode switching pattern.

[0086] Similarly, when two coils are driven and the first duty cycle command value D1 is 1 or less and greater than 0.5, during the period from time t36 to time t37, both the β-phase first coil 33 (β1) and the β-phase second coil 34 (β2) are charged by the fourth mode switching pattern. During the period from time t37 to time t38, both the β-phase first coil 33 (β1) and the β-phase second coil 34 (β2) are discharged by the second mode switching pattern. During the period from time t38 to time t39, both the β-phase first coil 33 (β1) and the β-phase second coil 34 (β2) are charged by the first mode switching pattern. During the period from time t39 to time t40, both the β-phase first coil 33 (β1) and the β-phase second coil 34 (β2) are discharged by the second mode switching pattern. During the period from time t40 to time t41, both the β-phase first coil 33 (β1) and the β-phase second coil 34 (β2) are charged by the switching pattern of the fourth mode.

[0087] As can be understood from the above explanation, as the first duty cycle command value D1 decreases from 1 to 0.5, the first and fourth modes that charge each β-phase coil 33(β1) and 34(β2) increase, while the second mode that discharges from each β-phase coil 33(β1) and 34(β2) decreases. For example, when the first duty cycle command value D1 is 0.5, only the first and fourth modes that charge each β-phase coil 33(β1) and 34(β2) remain. For example, as the first duty cycle command value D1 decreases from 0.5 to 0, the first and fourth modes that charge each β-phase coil 33(β1) and 34(β2) decrease, while the third mode that discharges from each β-phase coil 33(β1) and 34(β2) increases.

[0088] Figure 8 shows the direction of the magnetic flux generated in the rotating electric machine 16 when the PWM control unit 67 drives the two coils as described above during AC charging. In Figure 8, the reference numerals A11 and A21 indicate the direction of the magnetic flux generated in the β-phase first coil 33 (β1), and the reference numerals A12 and A22 indicate the direction of the magnetic flux generated in the β-phase second coil 34 (β2).

[0089] When AC charging, the PWM control unit 67 drives two coils, causing out-of-phase currents (currents flowing in opposite directions) to flow through the β-phase first coil 33 (β1) and the β-phase second coil 34 (β2). As a result, as shown in Figure 8, magnetic fluxes are generated in the β-phase first coil 33 (β1) and the β-phase second coil 34 (β2) in opposing directions, resulting in zero charging torque during AC charging. Thus, by having the PWM control unit 67 drive two coils during AC charging, fluctuations in the charging torque during AC charging can be suppressed. However, when the PWM control unit 67 drives two coils, the inductance of the rotating electric machine 16 decreases, increasing the ripple of the current flowing during AC charging.

[0090] Figure 9 shows the switching pattern of the second power conversion unit 13 when one coil is driven. As can be understood by comparing Figure 4 and Figure 9, the switching pattern of the second power conversion unit 13 when one coil is driven differs from the switching pattern of the second power conversion unit 13 when two coils are driven, in that the elements b3H, b3L, b4H, and b4L included in the fourth full bridge circuit 13b are in the off state in all modes.

[0091] The timing chart for the case where the first duty cycle command value D1 is greater than or equal to 0 and less than 0.5 when one coil is driven corresponds to the timing chart in Figure 5 with "b3H", "b3L", "b4H", and "b4L" removed. Therefore, the states of the elements b1H, b1L, b2H, and b2L included in the third full-bridge circuit 13a when the first duty cycle command value D1 is greater than or equal to 0 and less than 0.5 when one coil is driven will be explained below with reference to Figure 5.

[0092] When driving one coil, the PWM control unit 67 compares the magnitude of the first duty cycle command value D1 with the carrier wave CW, and generates a control signal such that if the first duty cycle command value D1 is less than the value of the carrier wave CW, the element b2H of the high-side arm turns off and the element b2L of the low-side arm turns on. Also, when driving one coil, the PWM control unit 67 generates a control signal such that if the first duty cycle command value D1 is greater than or equal to the value of the carrier wave CW, the element b2H of the high-side arm turns on and the element b2L of the low-side arm turns off.

[0093] When driving one coil, the PWM control unit 67 compares the second duty cycle command value D2 with the carrier wave CW, and generates a control signal such that if the second duty cycle command value D2 is less than the value of the carrier wave CW, the element b1H of the high-side arm turns off and the element b1L of the low-side arm turns on. Also, when driving one coil, the PWM control unit 67 generates a control signal such that if the second duty cycle command value D2 is greater than or equal to the value of the carrier wave CW, the element b1H of the high-side arm turns on and the element b1L of the low-side arm turns off.

[0094] When driving one coil, the PWM control unit 67 generates a control signal such that all of the element sections b3H, b3L, b4H, and b4L included in the fourth full-bridge circuit 13b are turned off, regardless of the first duty cycle command value D1 and the second duty cycle command value D2.

[0095] Referring to Figure 5, when one coil is driven and the first duty cycle command value D1 is greater than or equal to 0 and less than 0.5, during the period from time t1 to time t2, only the β-phase first coil 33 (β1) is charged by the fourth mode switching pattern shown in Figure 9. During the period from time t2 to time t3, only the β-phase first coil 33 (β1) is discharged by the third mode switching pattern. During the period from time t3 to time t4, only the β-phase first coil 33 (β1) is charged by the first mode switching pattern shown in Figure 9. During the period from time t4 to time t5, only the β-phase first coil 33 (β1) is discharged by the third mode switching pattern shown in Figure 9. During the period from time t5 to time t6, only the β-phase first coil 33 (β1) is charged by the fourth mode switching pattern shown in Figure 9.

[0096] The state of element sections b1H, b1L, b2H, and b2L during the period from time t6 to time t11 is the same as the state of element sections b1H, b1L, b2H, and b2L during the period from time t1 to time t6.

[0097] The timing chart when the first duty cycle command value D1 is 0.5 while driving one coil corresponds to the timing chart in Figure 6 with "b3H", "b3L", "b4H", and "b4L" removed. Therefore, the states of elements b1H, b1L, b2H, and b2L included in the third full-bridge circuit 13a when the first duty cycle command value D1 is 0.5 while driving one coil will be explained below with reference to Figure 6.

[0098] Referring to Figure 6, when one coil is driven and the first duty cycle command value D1 is 0.5, during the period from time t21 to time t22, only the β-phase first coil 33 (β1) is charged by the fourth mode switching pattern shown in Figure 9. During the period from time t22 to time t23, only the β-phase first coil 33 (β1) is charged by the first mode switching pattern shown in Figure 9. During the period from time t23 to time t24, only the β-phase first coil 33 (β1) is charged by the fourth mode switching pattern shown in Figure 9.

[0099] The state of element sections b1H, b1L, b2H, and b2L during the period from time t24 to time t27 is the same as the state of element sections b1H, b1L, b2H, and b2L during the period from time t21 to time t24.

[0100] The timing chart for the case where the first duty cycle command value D1 is 1 or less and greater than 0.5 when one coil is driven corresponds to the timing chart in Figure 7 with "b3H", "b3L", "b4H", and "b4L" removed. Therefore, the states of the elements b1H, b1L, b2H, and b2L included in the third full-bridge circuit 13a when the first duty cycle command value D1 is 1 or less and greater than 0.5 when one coil is driven will be explained below with reference to Figure 7.

[0101] Referring to Figure 7, when one coil is driven and the first duty cycle command value D1 is 1 or less and greater than 0.5, during the period from time t31 to time t32, only the β-phase first coil 33 (β1) is charged by the fourth mode switching pattern shown in Figure 9. During the period from time t32 to time t33, only the β-phase first coil 33 (β1) is discharged by the second mode switching pattern shown in Figure 9. During the period from time t33 to time t34, only the β-phase first coil 33 (β1) is charged by the first mode switching pattern shown in Figure 9. During the period from time t34 to time t25, only the β-phase first coil 33 (β1) is discharged by the second mode switching pattern shown in Figure 9. During the period from time t35 to time t36, only the β-phase first coil 33 (β1) is charged by the fourth mode switching pattern shown in Figure 9.

[0102] The state of element sections b1H, b1L, b2H, and b2L during the period from time t36 to time t41 is the same as the state of element sections b1H, b1L, b2H, and b2L during the period from time t31 to time t36.

[0103] Figure 10 shows the direction of the magnetic flux generated in the rotating electric machine 16 when the PWM control unit 67 drives the single coil as described above during AC charging. In Figure 10, the symbol A30 indicates the direction of the magnetic flux generated in the rotating electric machine 16.

[0104] During AC charging, the PWM control unit 67 drives one coil, causing current to flow only through the β-phase first coil 33 (β1). As a result, as shown in Figure 10, a magnetic flux is generated from the β-phase first coil 33 (β1) wound on one of the pair of teeth facing each other across the rotor 31, toward the β-phase first coil 33 (β1) wound on the other tooth. In this way, the PWM control unit 67 driving one coil during AC charging generates charging torque, but the inductance of the rotating electric machine 16 increases, thus reducing the ripple of the current flowing during AC charging.

[0105] As described above, when the PWM control unit 67 drives two coils during AC charging, fluctuations in the charging torque during AC charging can be suppressed, but the ripple of the current flowing during AC charging increases. On the other hand, when the PWM control unit 67 drives one coil during AC charging, charging torque is generated, but the ripple of the current flowing during AC charging decreases. Thus, there are mutually exclusive advantages and disadvantages to driving two coils and driving one coil.

[0106] Therefore, during AC charging, the PWM control unit 67 charges the energy storage device 11 by switching between two-coil drive and one-coil drive according to the charging torque. More specifically, for example, the PWM control unit 67 charges the energy storage device 11 by one-coil drive when the charging torque T is less than a predetermined value Ta, and charges the energy storage device 11 by two-coil drive when the charging torque T is equal to or greater than the predetermined value Ta.

[0107] Figure 11 shows the relationship between charging power P and charging torque T. In Figure 11, line 101 shows the charging torque T with respect to charging power P when the rotor angle θ is 90 degrees, and line 102 shows the charging torque T with respect to charging power P when the rotor angle θ is 45 degrees. When the rotor angle θ is 90 degrees, the charging torque T is greater than a predetermined value Ta when the charging power P is greater than P1. Also, when the rotor angle θ is 45 degrees, the charging torque T is greater than a predetermined value Ta when the charging power P is greater than P2.

[0108] As described above, the magnitude of the charging torque T relative to the charging power P changes depending on the rotor angle θ. Therefore, the PWM control unit 67 calculates the charging torque T based on the rotor angle θ and compares the calculated charging torque T with a predetermined value Ta. For example, the PWM control unit 67 calculates the charging torque T based on the following equation (1). In the following equation (1), I is the charging current and K is a coefficient determined by the specifications of the rotating electric machine 16. T = K × I × sinθ …(1)

[0109] Based on the operation of the PWM control unit 67 described above, the charging control process performed by the PWM control unit 67 during AC charging will now be explained with reference to Figure 12. Figure 12 is a flowchart showing the charging control process performed by the PWM control unit 67 during AC charging.

[0110] For example, during AC charging, the PWM control unit 67 executes the charging control process shown in Figure 12 each time the trough of the carrier wave CW, which is a triangular wave, arrives. In other words, the PWM control unit 67 executes the charging control process each time the start of one cycle Tc of the carrier wave CW arrives.

[0111] As shown in Figure 12, when the PWM control unit 67 starts the charge control process, it first calculates the charge current I from the requested charge power (step S1). Next, the PWM control unit 67 obtains the rotor angle θ from the rotor angle acquisition unit 68 (step S2). Subsequently, the PWM control unit 67 calculates the charge torque T by substituting the charge current I and the rotor angle θ into equation (1) above (step S3).

[0112] Next, the PWM control unit 67 determines whether the calculated charging torque T is less than a predetermined value Ta (step S4). If the PWM control unit 67 determines that the charging torque T is less than the predetermined value Ta (step S4: YES), it charges the energy storage device 11 by driving one coil based on the duty command values ​​(first duty command value D1 and second duty command value D2) obtained from the current control unit 65 (step S5).

[0113] On the other hand, if the PWM control unit 67 determines that the charging torque T is equal to or greater than a predetermined value Ta (step S4: NO), it drives two coils based on the duty command values ​​(first duty command value D1 and second duty command value D2) obtained from the current control unit 65 to charge the energy storage device 11 (step S6).

[0114] As described above, during AC charging, the PWM control unit 67 charges the energy storage device 11 by driving one coil when the charging torque T is less than a predetermined value Ta, and charges the energy storage device 11 by driving two coils when the charging torque T is equal to or greater than the predetermined value Ta.

[0115] Figure 13 shows an example of the waveform 111 of the current flowing through the β-phase first coil 33 (β1) and the waveform 112 of the current flowing through the β-phase second coil 33 (β2) when one coil is driven. Figure 14 shows an example of the waveform 121 of the power supply current flowing when one coil is driven. As shown in Figures 13 and 14, when the PWM control unit 67 drives one coil, charging torque is generated, but the ripple of the current flowing through the β-phase first coil 33 (β1) and the power supply current becomes relatively small. Note that, as shown in Figure 13, when one coil is driven, the value of the current flowing through the β-phase second coil 33 (β2) is zero.

[0116] Figure 15 shows an example of the waveform 131 of the current flowing through the β-phase first coil 33 (β1) and the waveform 132 of the current flowing through the β-phase second coil 33 (β2) when two coils are driven. Figure 16 shows an example of the waveform 141 of the power supply current flowing when two coils are driven. As shown in Figures 15 and 16, when the PWM control unit 67 drives two coils, the charging torque becomes zero, but the ripple of the current flowing through the β-phase first coil 33 (β1) and the β-phase second coil 33 (β2) and the power supply current becomes relatively large.

[0117] As described above, according to the electrical equipment 10 of this embodiment, when the charging torque T during AC charging is greater than or equal to a predetermined value Ta, both the β-phase first coil 33 (β1) and the β-phase second coil 34 (β2) are energized so that their magnetic fluxes cancel each other out, thereby suppressing vibrations in the charging torque generated in the rotating electric machine 16 and increasing the voltage boosting rate due to the relatively small inductance. On the other hand, when the charging torque T during AC charging is less than the predetermined value Ta, by energizing either the β-phase first coil 33 (β1) or the β-phase second coil 34 (β2), the charging efficiency can be improved while suppressing current ripple due to the relatively large inductance.

[0118] Furthermore, according to the electrical device 10 of this embodiment, the charging torque T, which changes depending on the rotor angle θ, can be calculated with high accuracy, so the timing when the charging torque T exceeds a predetermined value Ta can be detected with high accuracy.

[0119] Furthermore, according to the electrical equipment 10 of this embodiment, the rotating electric machine 16 employs a structure in which the β-phase first coil 33 (β1) and the β-phase second coil 34 (β2) are wound in the same slot of the same phase. By energizing both the β-phase first coil 33 (β1) and the β-phase second coil 34 (β2) so that their magnetic fields cancel each other out, it is possible to suppress vibrations in the charging torque generated in the rotating electric machine 16 and increase the voltage boosting rate with a relatively small inductance.

[0120] Furthermore, according to the electrical equipment 10 of this embodiment, when the rotating electric machine 16 is driven by the energy storage device 11, the power control unit 10a can function as an inverter of a multiple full-bridge circuit. When the energy storage device 11 is AC-charged by an external AC power source, the combination of the α-phase first coil 23 (α1) and the α-phase second coil 24 (α2), and the first full-bridge circuit 12a and the second full-bridge circuit 12b can function as an isolated bidirectional DC-DC converter. For example, in the case of boost operation during AC charging, rapid charging can be performed for the voltage of the energy storage device 11, which is higher than the charging voltage from the external AC power source.

[0121] Furthermore, according to the electrical equipment 10 of this embodiment, by adopting a structure in which the α-phase first coil 23 (α1) and the α-phase second coil 24 (α2) are wound in the same slot in the rotating electric machine 16, the degree of magnetic coupling between the α-phase first coil 23 (α1) and the α-phase second coil 24 (α2) can be increased, thereby improving charging efficiency.

[0122] Although one embodiment of the present invention has been described above, the present invention is not limited to the above embodiment, and various modifications and substitutions can be made without departing from the spirit of the present invention.

[0123] For example, in the above embodiment, the PWM control unit 67 is shown to switch between two-coil drive and one-coil drive according to the charging torque T. However, the two-coil drive and one-coil drive may be switched according to the charging power or charging current determined from charger information, battery information, rotor angle, and torque threshold, etc.

[0124] Furthermore, in the above embodiment, the PWM control unit 67 is shown as energizing the β-phase first coil 33 (β1) when driving one coil, but the PWM control unit 67 may also energize the β-phase second coil 33 (β2) when driving one coil.

[0125] The embodiments of the present invention are presented as examples and are not intended to limit the scope of the invention. These embodiments can be carried out in various other forms, and various omissions, substitutions, and modifications can be made without departing from the spirit of the invention. These embodiments and their variations are included in the scope and spirit of the invention, as well as in the claims and their equivalents. [Explanation of Symbols]

[0126] 10...Electrical equipment, 10a...Power control unit, 11...Energy storage device, 12...First power conversion unit, 12a...First full-bridge circuit (third full-bridge circuit), 12b...Second full-bridge circuit (fourth full-bridge circuit), 13...Second power conversion unit, 13a...Third full-bridge circuit (first full-bridge circuit), 13b...Fourth full-bridge circuit (second full-bridge circuit), 14...DC charging terminal, 15...AC charging terminal, 16...Rotating electric machine, 17...Gate drive unit, 18...Electronic control unit (control device), 22...First switch, 23…α-phase 1st coil (α1) (3rd coil), 24…α-phase 2nd coil (α2) (4th coil), 25…1st disconnector (3rd disconnector), 26…2nd disconnector (4th disconnector), 32…2nd switch, 33…β-phase 1st coil (β1) (1st coil), 34…β-phase 2nd coil (β2) (2nd coil), 35…3rd disconnector (1st disconnector), 36…4th disconnector (2nd disconnector), 41…Rotor, 42…Stator core, 43…Slot, SL1…1st slot, SL2…2nd slot, SL3…3rd slot, SL4…4th slot

Claims

1. Energy storage device, Rotating electric machines and, A power control unit connected to the energy storage device and the rotating electric machine, which controls the power transfer between the energy storage device and the rotating electric machine, The aforementioned power control unit has an AC charging terminal for connecting to an external AC power source, Electrical equipment equipped with, The aforementioned rotating electric machine comprises a first coil and a second coil, The aforementioned power control unit is A first full-bridge circuit connected to both ends of the first coil, A second full-bridge circuit connected to both ends of the second coil, A first disconnecting connector is connected between one end of the first coil and the first full-bridge circuit, A second disconnecting connector is connected between one end of the second coil and the second full-bridge circuit, A control device for controlling the energization of the first coil and the second coil, Equipped with, The AC charging terminals are connected to both ends of the first and second disconnectors, respectively, so that when current supplied from the external AC power source flows through the magnetically coupled first and second coils, their magnetic fluxes cancel each other out. The control device is During AC charging, in which the energy storage device is charged by power supplied from the external AC power source, the first disconnector and the second disconnector are controlled to be in a disconnected state. When the charging torque generated during AC charging exceeds a predetermined value, both the first coil and the second coil are energized. If the charging torque is less than the predetermined value, energize one of the first coil and the second coil. Electrical equipment.

2. The aforementioned rotating electric machine further includes a position sensor for detecting the rotor angle, The control device calculates the charging torque based on the rotor angle obtained from the output signal of the position sensor. The electrical equipment according to claim 1.

3. In the aforementioned rotating electric machine, the first coil and the second coil are wound in the same slot of the same phase. The control device controls the direction of current flow supplied from the external AC power source so that, when both the first coil and the second coil are energized, the magnetic fluxes of the first coil and the second coil cancel each other out. The electrical equipment according to claim 1.

4. The rotating electric machine comprises a third coil and a fourth coil whose phases are orthogonal to the first coil and the second coil, The aforementioned power control unit is A third full-bridge circuit connected to both ends of the third coil, A fourth full-bridge circuit connected to both ends of the fourth coil, A third disconnecting connector connected between the positive terminals of the third full-bridge circuit and the fourth full-bridge circuit, A fourth disconnector connected between the negative terminals of the third full-bridge circuit and the fourth full-bridge circuit, Equipped with, The electrical equipment according to any one of claims 1 to 3.

5. In the aforementioned rotating electric machine, the third coil and the fourth coil are wound in the same slot. The electrical equipment according to claim 4.

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