Straddled vehicle

Abstract

The present invention provides a straddled vehicle equipped with a small and lightweight high-voltage hybrid system. The straddled vehicle includes an engine, a drive wheel, a high-voltage power supply system, a permanent magnet motor generator, a first MG control device, and a first power transfer device electrically connected to the high-voltage power supply system without a secondary battery that is electrically connected to the high-voltage power supply system and that functions at the high voltage. The first MG control device performs field weakening control on the first permanent magnet motor generator having the rotor which is provided with more magnetic poles than 2 / 3 of the number of teeth and which rotates at the same speed as the engine of the straddled vehicle so that, via field-weakening control using the high voltage as a power source, a current component of the field-weakening control is supplied to the winding to overcome reluctance that increases in the high-rotation range of the engine of the straddled vehicle, while the amount of voltage suppression caused by the field-weakening control is increased as a result of an increase in reluctance due to an increase in the magnetic poles of the first permanent magnet motor generator. The field-weakening control is performed using the high voltage higher than the low voltage of the low-voltage battery as a power supply.

Description

Straddled Vehicle

[0001] The present invention relates to a straddled vehicle.

[0002] For example, Patent Document 1 discloses a vehicle equipped with a motor generator connected to an engine. The vehicle shown in Patent Document 1 is an automobile (see FIG. 2 of Patent Document 1). The motor generator is connected to a high-voltage battery via an inverter.

[0003] Patent Document 2 also shows a vehicle equipped with a motor generator. The motor generator shown in Patent Document 2 is connected to an engine via a reduction mechanism such as a belt or chain. The motor generator is supplied with high-voltage electric power from a power storage device. The electric power generated by the motor generator is also supplied to the power storage device at high voltage.

[0004] For example, Patent Document 3 discloses a saddle-ride type vehicle. The saddle-ride type vehicle disclosed in Patent Document 3 includes an engine, a starter-generator, a battery, and a control device. The battery is a low-voltage battery that drives the starter-generator. The control device disclosed in Patent Document 3 performs field-weakening control of the starter-generator so as not to apply a voltage higher than the battery voltage to the low-voltage battery.

[0005] Japanese Patent Laid-Open No. 9-084210 Japanese Patent Laid-Open No. 2005-180254 Japanese Patent Laid-Open No. 2017-129065

[0006] In some cases, it is desirable for a saddle-type vehicle to have a high-voltage hybrid system that is small, lightweight, and compatible with the rotational speed range of the engine of the saddle-type vehicle.

[0007] An object of the present invention is to provide a saddle-type vehicle equipped with a high-voltage hybrid system that is small, lightweight, and compatible with the rotational speed range of the engine of the saddle-type vehicle.

[0008] A straddle-type vehicle is configured so that the vehicle's posture is controlled by the driver's weight shift while driving. Therefore, from the standpoint of operability and driving performance, there is a trend toward straddle-type vehicles being required to be small and lightweight. Accordingly, there is a trend toward hybrid systems and their components being mounted on straddle-type vehicles being small and lightweight.

[0009] A motor generator capable of handling high voltages has a structure that allows it to generate the required power even at low rotation speeds, such as the engine's idle speed. For example, a motor generator capable of handling high voltages may have a stronger magnet than a motor generator that does not handle high voltages.

[0010] For example, it is conceivable to apply the motor generator of an automobile capable of handling high voltages, as disclosed in Patent Documents 1 and 2, to a straddle-type vehicle.

[0011] However, saddle-type vehicle engines tend to operate over a wider range of rotational speeds, including higher rotational speeds, than automobile engines. This is because, while automobile engines are designed to output large torque at low rotational speeds in order to start and accelerate heavy automobiles, saddle-type vehicle engines are designed to start and accelerate relatively light saddle-type vehicles, and are therefore required to be small and lightweight in order to be installed in small and lightweight saddle-type vehicles.

[0012] When a motor generator configured to handle high voltages is driven by a saddle-ride vehicle engine that operates over a wide range of rotational speeds, the induced voltage of the motor generator may become excessive at high rotational speeds of the saddle-ride vehicle engine, causing the terminal voltage of the motor generator to exceed the range that can be controlled by the control device. For example, when the terminal voltage of the motor generator exceeds the controllable range, it is necessary to stop the control of power generation.

[0013] In order to suppress the voltage of the motor generator, it is conceivable to connect the engine of the saddle-ride type vehicle to the motor generator via a reduction mechanism such as a belt or chain as shown in Patent Document 2. However, providing a reduction mechanism for the motor generator increases the size and weight of the hybrid system of the saddle-ride type vehicle.

[0014] The inventors conducted extensive research into a compact, lightweight motor generator that can accommodate the rotational speed range of the engine of a saddle-ride type vehicle. As a result, they discovered a configuration that uses a high voltage as a power source to perform field-weakening control on a permanent magnet motor generator that rotates at the same speed as the engine of the saddle-ride type vehicle and has magnetic poles with more than two-thirds the number of teeth. The high voltage is higher than the low voltage of the low-voltage battery.

[0015] When the number of magnetic poles in a permanent magnet motor generator is large, the angular velocity in electrical angle is large. This large reluctance increases the amount of voltage suppression by field-weakening control. On the other hand, when the number of magnetic poles is large, the angular velocity increases even more at high rotational speeds of the engine of a saddle-ride vehicle. The reluctance, which increases with increasing angular speed, is an impedance component, and the impedance, which increases at high rotational speeds, opposes the current component of field-weakening control. However, by using a high-voltage power source, the current can be controlled to the field-weakening target, regardless of the large impedance at high rotational speeds caused by the large number of magnetic poles. In other words, by using a high-voltage power source for field-weakening control, the current component of field-weakening control overcomes the increased impedance at high rotational speeds and is supplied to the winding.

[0016] More specifically, the induced electromotive force E in the winding of a permanent magnet motor generator depends mainly on the product φ·ω of the magnetic flux φ interlinked with the winding and the angular velocity ω in electrical angle. In contrast, the main effective component for generating a terminal voltage suppressed from the induced electromotive force by field-weakening control (also simply referred to as "suppressing the induced electromotive force") is expressed as L·ω·Id. L·ω is the reluctance of the winding. L is the inductance, and is usually a fixed value that depends on the structure of the winding, etc. Id is the field-weakening current generated by field-weakening control, and the magnitude of the field-weakening current Id is controlled by a control device. Angular velocity ω is the speed based on the period in which a pair of magnetic poles passes near a certain tooth. Angular velocity ω can be expressed, for example, by the following equation: ω = (P / 2) × (N rpm / 60) × 2π (P: number of magnetic poles, N: crankshaft rotation speed) At high rotation speeds of a saddle-type vehicle engine, a high induced electromotive force E is generated in the winding due to an increase in φ and ω. Note that when the number of magnetic poles is more than two-thirds the number of teeth, the induced electromotive force E appears to increase in proportion to the increase in angular velocity ω. However, if the number of magnetic poles is increased to more than two-thirds the number of teeth while maintaining the size and weight of the permanent magnet motor generator, the physical size of each magnetic pole becomes smaller, and the magnetic flux φ in the winding decreases accordingly. In other words, the decrease in magnetic flux φ changes in a direction that offsets the increase in angular velocity ω. For this reason, the change in induced electromotive force E caused by increasing the number of magnetic poles is suppressed.

[0017] Field-weakening control by a control device can suppress induced electromotive force that increases in the high rotation range. When the number of magnetic poles is more than two-thirds of the number of teeth, the angular velocity ω of the component L·ω·Id suppressed by field-weakening control is larger than when the number of magnetic poles is two-thirds or less of the number of teeth. Therefore, in a permanent magnet motor generator in which the number of magnetic poles is more than two-thirds of the number of teeth, the amount of suppression of induced electromotive force by field-weakening control is large.

[0018] The reluctance L·ω of the winding, together with pure resistance, constitutes the internal impedance Z of the winding. The impedance Z is an element that resists the winding current. The field-weakening current Id is a component of the current controlled by the control device. The field-weakening current Id also flows against the impedance Z of the winding. As described above, the reluctance that constitutes the impedance of the winding is L·ω, and an increase in angular velocity ω increases the reluctance component, which appears as an increase in impedance. The control device performs control, for example, by the duty ratio of the on-time, so that the field-weakening current Id reaches a target value regardless of changes in impedance Z. However, if the impedance Z increases and exceeds a controllable range, such as the upper limit of the duty ratio, the field-weakening current Id cannot maintain the required target value. The control device of the present disclosure performs field-weakening control using a high voltage power source, and can control the field-weakening current Id to reach the target value by overcoming the large impedance Z caused by the large reluctance L·ω. That is, regardless of the reluctance L·ω that increases when the number of magnetic poles is more than two-thirds the number of teeth, the field weakening current Id can be maintained at the target value even in the high rotation speed range of the engine of the saddle-ride type vehicle.

[0019] In this way, by performing field-weakening control on a permanent magnet motor generator having more than two-thirds the number of teeth using a high voltage as a power source, a synergistic effect is achieved in which greater voltage suppression by field-weakening control can be achieved at higher engine speeds. Due to the synergistic effect of greater voltage suppression by field-weakening control at higher engine speeds, the high-voltage permanent magnet motor generator can suppress fluctuations in terminal output voltage over a wide rotational speed range, from low to high, of the saddle-ride vehicle engine. This suppresses fluctuations in the voltage supplied from the permanent magnet motor generator to the high-voltage power supply system via the control device in response to changes in rotational speed. Therefore, it is possible to supply high voltage with suppressed fluctuations over a wide rotational speed range of the saddle-ride vehicle engine without providing a high-voltage battery in the high-voltage power supply system or a reduction mechanism such as a belt or chain in the engine.

[0020] Patent Document 3 discloses an example of field-weakening control of a motor-generator having a rotor fixed to a crankshaft and magnetic poles with 4 / 3 the number of slots. However, Patent Document 3 uses a control device to control the starter-generator so as not to apply a voltage higher than the battery voltage of the low-voltage battery. In contrast, the technology disclosed herein reverses the concept of Patent Document 3, which controls the starter-generator so as not to apply a voltage higher than the battery voltage of the low-voltage battery. By using a high voltage higher than the low-voltage battery as a power source, field-weakening control is performed on a permanent magnet motor-generator having magnetic poles with more than two-thirds the number of teeth. This allows the field-weakening current Id to be maintained even at high rotation speeds, regardless of the reluctance L·ω that increases when the number of magnetic poles is greater than two-thirds the number of teeth. In other words, the effect of large field-weakening control due to a large angular velocity ω can be exerted over a wide rotation speed range of the saddle-ride vehicle engine, regardless of the large angular velocity ω.

[0021] According to the technology disclosed herein, greater voltage suppression by field weakening control is exerted at higher rotational speeds, resulting in a synergistic effect that suppresses voltage fluctuations over a wide rotational speed range, including the high rotational speed range of the engine of a saddle-ride type vehicle. Therefore, according to the technology disclosed herein, it is possible to realize a high-voltage hybrid system that is small, lightweight, and compatible with the rotational speed range of the engine of a saddle-ride type vehicle.

[0022] In order to achieve the above object, according to one aspect of the present invention, a vehicle has the following configuration.

[0023] (1) An engine having a crankshaft and outputting torque via the crankshaft; drive wheels to which at least a portion of the torque output from the engine is mechanically transmitted and which drive a saddle-ride type vehicle; a high-voltage power supply system operating at a high voltage higher than the low voltage of a low-voltage power supply system connected to a low-voltage battery; a first permanent magnet motor generator comprising: a stator having a plurality of teeth arranged in the circumferential direction and windings wound on each of the plurality of teeth; and a rotor having magnetic poles provided on a rotating shaft that is coaxial with and rotates at the same speed as the crankshaft, and which applies torque to the drive wheels by powering while receiving and sending electric power to and from the high-voltage power supply system, and which generates electricity by receiving torque from the engine or the drive wheels; and a first MG control device that is not connected to a battery but is electrically connected to the high-voltage power supply system and is electrically connected to the first permanent magnet motor generator, and which controls the powering and power generation of the first permanent magnet motor generator. a first power transfer device which is one of a capacitor for transferring power, a permanent magnet turbo motor generator provided in an electric turbocharger, a permanent magnet supercharger motor generator provided in an electric supercharger, and a second permanent magnet motor generator which is separate from the first permanent magnet motor generator and performs power running and generates electricity, electrically connected to the high-voltage power supply system without being connected to the battery which functions at high voltage, wherein the first MG control device increases the amount of voltage suppression by field weakening control due to an increase in reluctance caused by an increase in magnetic poles of the first permanent magnet motor generator, and by field weakening control using the high voltage as a power source, overcomes the reluctance which increases in the high rotation speed range of the engine of the saddle-ride type vehicle and supplies a current component of the field weakening control to the windings; The first permanent magnet motor generator rotates at the same speed as the engine of the saddle-ride vehicle and has a rotor with magnetic poles that are greater than two-thirds the number of teeth, and the field-weakening control is performed using the high voltage, which is higher than the low voltage of the low-voltage battery, as a power source.

[0024] (1) A saddle-ride type vehicle includes an engine, drive wheels, a high-voltage power supply system, a first permanent magnet motor generator, and a first MG control device. The engine has a crankshaft. The engine outputs torque via the crankshaft. The drive wheels drive the saddle-ride type vehicle. At least a portion of the torque output from the engine is mechanically transmitted to the drive wheels. The high-voltage power supply system operates at a high voltage. The high voltage is higher than the low voltage of a low-voltage power supply system to which a low-voltage battery is connected. The first permanent magnet motor generator includes a stator and a rotor. The stator has a plurality of teeth and a winding. The plurality of teeth are arranged circumferentially. A winding is wound around each of the plurality of teeth. The rotor is provided on a rotating shaft that is coaxial with the crankshaft and rotates at the same speed. The rotor has magnetic poles. The first permanent magnet motor generator exchanges electric power with the high-voltage power supply system. The first permanent magnet motor generator applies torque to the drive wheels by powering them. The first permanent magnet motor generator receives torque from the engine or the drive wheels and generates electricity. The first MG control device is electrically connected to a high-voltage power supply system without being connected to a battery. The battery is a secondary battery. The first MG control device is also electrically connected to the first permanent magnet motor generator. The first MG control device controls the powering and power generation of the first permanent magnet motor generator. The saddle-ride type vehicle is a hybrid vehicle. The engine, drive wheels, high-voltage power supply system, first permanent magnet motor generator, and first MG control device are included in a high-voltage hybrid system of the saddle-ride type vehicle. The saddle-ride type vehicle also includes a first power transfer device. The first power transfer device is electrically connected to the high-voltage power supply system without being connected to a battery. The first power transfer device is one of a capacitor that transfers power, a permanent magnet turbo motor generator provided in the electric turbocharger, a permanent magnet supercharger motor generator provided in the electric supercharger, and a second permanent magnet motor generator. The second permanent magnet motor generator is a motor generator that is separate from the first permanent magnet motor generator and performs power running and generates electricity.

[0025] Saddle-ride type vehicles are configured so that the vehicle's posture is controlled in accordance with the driver's weight shift while driving. Therefore, from the standpoints of operability and driving performance, saddle-ride type vehicles tend to be small and lightweight. Accordingly, hybrid systems and their components mounted on saddle-ride type vehicles also tend to be small and lightweight. Furthermore, when a motor generator configured to handle high voltages is driven by a saddle-ride type vehicle engine that operates over a wide rotational speed range, the induced electromotive force of the motor generator may become excessively large at high rotational speeds of the saddle-ride type vehicle engine, potentially causing the terminal voltage of the motor generator to exceed the range controllable by the control device. The first MG control device in the saddle-ride type vehicle (1) performs field-weakening control on a first permanent magnet motor generator that rotates at the same speed as the saddle-ride type vehicle engine and has a rotor with magnetic poles that number more than two-thirds the number of teeth, using a high voltage that is higher than the low voltage of a low-voltage battery as a power source. As a result, the first MG control device increases the amount of voltage suppression by field weakening control due to the increase in reluctance caused by the increase in magnetic poles of the first permanent magnet motor generator, and performs field weakening control using a high voltage as a power source to overcome the reluctance that increases in the high rotation speed range of the engine of the saddle-ride type vehicle and supply a current component of field weakening control to the winding. Here, the increase in reluctance due to the increase in magnetic poles means that there are more magnetic poles than two-thirds the number of teeth.

[0026] Field-weakening control by a control device can suppress induced electromotive force that increases in the high rotation range. When the number of magnetic poles is more than two-thirds of the number of teeth, the angular velocity ω of the suppression component L·ω·Id by field-weakening control is larger than when the number of magnetic poles is two-thirds or less of the number of teeth. Therefore, in a permanent magnet motor generator in which the number of magnetic poles is more than two-thirds of the number of teeth, the amount of suppression of induced electromotive force by field-weakening control is large. Here, L is inductance. Id is the field-weakening current by field-weakening control. ω is the angular velocity in electrical angle. L·ω is the reluctance of the winding.

[0027] The reluctance L·ω of the winding, together with pure resistance, constitutes the internal impedance Z of the winding. The impedance Z is an element that resists the winding current. The field weakening current Id is a component of the current controlled by the control device. The field weakening current Id also flows against the impedance Z of the winding. As described above, the reluctance that constitutes the impedance of the winding is L·ω, and it increases as the angular velocity ω increases. The control device performs control, for example, by the duty ratio of the on-time, so that the field weakening current Id reaches a target value regardless of changes in the impedance Z. However, if the impedance Z increases and exceeds a controllable range, such as the upper limit of the duty ratio, the field weakening current Id cannot maintain the required target value. The control device of the present disclosure performs field weakening control using a high voltage power source, and can control the field weakening current Id to reach the target value by overcoming the large impedance Z caused by the large reluctance L·ω. That is, even if the reluctance L·ω is large because the number of magnetic poles is more than two-thirds the number of teeth, the field weakening current Id can be maintained at the target value in the high rotation speed range of the engine of the saddle-ride type vehicle.

[0028] In this way, by performing field-weakening control on a permanent magnet motor generator having more than two-thirds the number of teeth using a high voltage as a power source, a synergistic effect is achieved in which greater voltage suppression by field-weakening control can be achieved at higher engine speeds. Due to the synergistic effect of greater voltage suppression by field-weakening control at higher engine speeds, the high-voltage permanent magnet motor generator can suppress fluctuations in terminal output voltage over a wide rotational speed range, from low to high, of the saddle-ride vehicle engine. This suppresses fluctuations in the voltage supplied from the permanent magnet motor generator to the high-voltage power supply system via the control device in response to changes in rotational speed. Therefore, it is possible to supply high voltage with suppressed fluctuations over a wide rotational speed range of the saddle-ride vehicle engine without providing a high-voltage battery in the high-voltage power supply system or a reduction mechanism such as a belt or chain in the engine.

[0029] In the saddle-type vehicle (1), the field-weakening control exerts a synergistic effect of greater voltage suppression at higher engine speeds, thereby suppressing voltage fluctuations over a wide range of engine speeds, including the high-speed range of the saddle-type vehicle's engine. This makes it possible to realize a high-voltage hybrid system that is compact, lightweight, and compatible with the engine's wide range of engine speeds.

[0030] According to one aspect of the present invention, a vehicle can employ the following configuration: (2) The saddle-ride type vehicle of (1), further comprising a starter motor that operates on the low voltage of the low-voltage power supply system and starts the engine without powering the first permanent magnet motor generator, and the first MG control device performs the field-weakening control on the first permanent magnet motor generator that rotates at the same speed as the engine of the saddle-ride type vehicle and has a rotor with magnetic poles that number more than two-thirds of the teeth, using as a power source the high voltage that is higher than the low voltage of the low-voltage battery that operates the starter motor.

[0031] The straddle-type vehicle (2) includes a starter motor that operates at a low voltage and starts the engine. Therefore, the engine can be started even if the first permanent magnet motor generator does not have an engine-starting function. Generally, engine-starting motors output a torque large enough to start the engine, and therefore often require, for example, a stronger magnetic flux. However, omitting the starting function from the first permanent magnet motor generator increases structural flexibility, allowing, for example, the use of a weaker magnet compared to a motor with a starting function. The first MG control device uses a high voltage, which is higher than the low-voltage battery that operates the starter motor, as its power source and performs field-weakening control on the first permanent magnet motor generator, which has a rotor with more than two-thirds the number of magnetic poles. Because there is a high degree of design freedom for the induced electromotive force at high rotational speeds, which is the target of field-weakening control using a high-voltage power source, a wider rotational speed range of the straddle-type vehicle engine can be accommodated. As a result, a small, lightweight, and high-voltage hybrid system capable of accommodating a wider rotational speed range can be realized.

[0032] According to one aspect of the present invention, the vehicle can employ the following configuration: (3) In the saddle-ride type vehicle of (1) or (2), the first power transfer device is the capacitor, the first permanent magnet motor generator receives power from the capacitor to power itself and apply torque to the crankshaft, and the first MG control device performs the field-weakening control on the first permanent magnet motor generator, which rotates at the same speed as the engine of the saddle-ride type vehicle and has a rotor with magnetic poles that number more than two-thirds of the teeth, using the high voltage, to which the capacitor is connected, as a power source that is higher than the low voltage of the low-voltage battery.

[0033] Unlike secondary batteries, capacitors charge and discharge without chemical reactions at their electrodes. Therefore, they can be made smaller and lighter than secondary batteries that can input and output the same current at the same voltage. The first MG control device performs the field-weakening control on a first permanent magnet motor-generator having a rotor with magnetic poles that are more than two-thirds the number of teeth. The high voltage, which is higher than the low voltage of the low-voltage battery and to which the capacitor is connected, is used as a power source. Because the first permanent magnet motor-generator supplies power to the capacitor rather than the secondary battery and charges the capacitor, a high-voltage hybrid system can be realized that is compact, lightweight, and capable of operating at a wider range of rotational speeds while expanding the range of high-voltage applications.

[0034] According to one aspect of the present invention, the vehicle can employ the following configuration: (4) The saddle-ride type vehicle of any one of (1) to (3), wherein the first power transfer device is the permanent magnet turbo motor generator provided on the electric turbocharger, the first permanent magnet motor generator receives electric power generated by the permanent magnet turbo motor generator to power and apply torque to the crankshaft, and the first MG control device performs the field-weakening control on the first permanent magnet motor generator, which rotates at the same speed as the engine of the saddle-ride type vehicle and has a rotor with magnetic poles that have more than two-thirds the number of teeth, using the high voltage, which is higher than the low voltage of the low-voltage battery and to which the electric turbocharger is connected, as a power source.

[0035] According to (4), the power generated by the first permanent magnet motor generator can be used to increase the capacity of the electric turbocharger. This allows for increased engine capacity and a more compact engine. Furthermore, for example, when the engine output is high, the electric turbocharger is driven by engine exhaust gas, allowing the permanent magnet turbo motor generator to generate power. The first permanent magnet motor generator receives the power generated by the permanent magnet turbo motor generator and powers the crankshaft, applying torque to the crankshaft. The first permanent magnet motor generator can assist the engine without a secondary battery that operates at high voltage. This not only eliminates the need for a secondary battery, but also allows for a more compact engine. Therefore, a compact, lightweight, and high-voltage hybrid system capable of operating over a wide range of rotational speeds can be realized, while minimizing the reduction in torque or power transmitted to the drive wheels.

[0036] According to one aspect of the present invention, the vehicle can employ the following configuration: (5) The saddle-ride type vehicle of any one of (1) to (4), wherein the first power transfer device is the permanent magnet supercharger motor generator provided on the electric supercharger, the first permanent magnet motor generator receives electric power generated by the permanent magnet supercharger motor generator to power and apply torque to the crankshaft, and the first MG control device performs the field-weakening control on the first permanent magnet motor generator, which rotates at the same speed as the engine of the saddle-ride type vehicle and has a rotor with magnetic poles that number more than two-thirds of the number of teeth, using the high voltage, which is higher than the low voltage of the low-voltage battery and to which the electric supercharger is connected, as a power source.

[0037] According to (5), the power generated by the first permanent magnet motor generator can be used to increase the capacity of the electric supercharger. This allows for increased engine capacity and a more compact engine. Furthermore, when the speed of the electric supercharger is reduced, the permanent magnet supercharger motor generator can generate power by utilizing the rotational inertia of the electric supercharger. The first permanent magnet motor generator receives the power generated by the permanent magnet supercharger motor generator and applies torque to the crankshaft. The first permanent magnet motor generator can assist the engine without a secondary battery that operates at high voltage. This not only eliminates the need for a secondary battery, but also allows for a more compact engine. Therefore, a compact, lightweight, and high-voltage hybrid system that can accommodate a wide range of rotational speeds can be realized while minimizing the reduction in torque or power transmitted to the drive wheels.

[0038] According to one aspect of the present invention, the vehicle can employ the following configuration: (6) The saddle-ride type vehicle of any one of (1) to (5), wherein the first power transfer device is the second permanent magnet motor generator, and the first permanent magnet motor generator receives electric power generated by the second permanent magnet motor generator to power the first permanent magnet motor generator and apply torque to the crankshaft, and the first MG control device performs the field-weakening control on the first permanent magnet motor generator, which rotates at the same speed as the engine of the saddle-ride type vehicle and has a rotor with magnetic poles that have more than two-thirds the number of teeth, using the high voltage, which is higher than the low voltage of the low-voltage battery and to which the second permanent magnet motor generator is connected, as a power source.

[0039] According to (6), the second permanent magnet motor generator can be powered by the electric power generated by the first permanent magnet motor generator. Furthermore, when the second permanent magnet motor generator receives torque, the second permanent magnet motor generator can generate electricity. The first permanent magnet motor generator receives the electric power generated by the second permanent magnet motor generator and powers the engine, applying torque to the crankshaft. The first permanent magnet motor generator can assist the engine without a secondary battery that functions at high voltage. This not only eliminates the need for a secondary battery, but also allows the engine to be made smaller. Therefore, the high-voltage hybrid system provided in the saddle-type vehicle can be made smaller and lighter, and can be adapted to a wide range of rotational speeds.

[0040] According to one aspect of the present invention, the vehicle can employ the following configuration: (7) The saddle-ride type vehicle of any one of (1) to (6), wherein the first power transfer device is the second permanent magnet motor generator mechanically connected to a rotating shaft provided in a torque transmission path between the crankshaft and the drive wheels, the first permanent magnet motor generator receives electric power generated by the second permanent magnet motor generator and powers to apply torque to the crankshaft, and the first MG control device performs the field-weakening control on the first permanent magnet motor generator, which rotates at the same speed as the engine of the saddle-ride type vehicle and has a rotor with magnetic poles that have more than two-thirds the number of teeth, using the high voltage, which is higher than the low voltage of the low-voltage battery and to which the second permanent magnet motor generator is connected, as a power source.

[0041] According to (7), the second permanent magnet motor generator can be powered by the electric power generated by the first permanent magnet motor generator. This allows, for example, drive wheels to be driven from a position on a transmission path different from that of the engine. This allows for greater design flexibility in the running state of a saddle-type vehicle. Furthermore, when the second permanent magnet motor generator is rotating at a high speed, the second permanent magnet motor generator can generate electricity. The first permanent magnet motor generator receives the electric power generated by the second permanent magnet motor generator and powers the engine, applying torque to the crankshaft. The first permanent magnet motor generator can assist the engine at high voltage without a secondary battery that functions at high voltage. This not only eliminates the need for a secondary battery, but also allows for a smaller engine. This allows for a compact, lightweight, and high-voltage hybrid system that can accommodate a wide range of rotational speeds.

[0042] According to one aspect of the present invention, the vehicle can employ the following configuration: (8) The saddle-ride type vehicle of any one of (1) to (7), wherein the first power transfer device is the capacitor, and the saddle-ride type vehicle further includes a second power transfer device that is one of the permanent magnet turbo motor generator provided in the electric turbocharger, the permanent magnet supercharger motor generator provided in the electric supercharger, and the second permanent magnet motor generator that is separate from the first permanent magnet motor generator and performs power running and generates electricity, and the first MG control device performs the field-weakening control on the first permanent magnet motor generator, which rotates at the same speed as the engine of the saddle-ride type vehicle and has a rotor with magnetic poles that have more than two-thirds the number of teeth, using the high voltage, which is higher than the low voltage of the low-voltage battery and to which the capacitor is connected, as a power source.

[0043] Unlike secondary batteries, capacitors charge and discharge without chemical reactions at the electrodes. Therefore, they can be made smaller and lighter than secondary batteries that can input and output the same current at the same voltage. The first MG control device performs field-weakening control on a first permanent magnet motor-generator having a rotor with magnetic poles that are more than two-thirds the number of teeth, using a high voltage that is higher than the low voltage of the low-voltage battery and at least the high voltage to which the capacitor is connected as a power source. Because the first permanent magnet motor-generator supplies power to the capacitor, rather than the secondary battery, and the capacitor is charged, a high-voltage hybrid system can be realized that is small, lightweight, and capable of operating at a wider range of rotational speeds while expanding the range of high-voltage applications.

[0044] According to one aspect of the present invention, the vehicle can employ the following configuration: (9) The saddle-ride type vehicle of (8), wherein the second power transfer device receives electric power from both the capacitor and the first permanent magnet motor generator for power running, and the first MG control device performs the field-weakening control on the first permanent magnet motor generator, which rotates at the same speed as the engine of the saddle-ride type vehicle and has a rotor with magnetic poles that number more than two-thirds of the teeth, using the high voltage, which is higher than the low voltage of the low-voltage battery and to which the capacitor is connected, as a power source.

[0045] (9) The second power transfer device can receive large amounts of power from both the capacitor and the first permanent magnet motor generator for power running. The first permanent magnet motor generator supplies power to the capacitor instead of the secondary battery, and the capacitor is charged. This makes it possible to realize a high-voltage hybrid system that is compact, lightweight, and compatible with a wider range of rotational speeds while expanding the range of high-voltage applications.

[0046] The terminology used herein is for the purpose of defining particular embodiments only and is not intended to limit the invention. As used herein, the term "and / or" includes any and all combinations of one or more of the associated listed components. As used herein, the use of the terms "including," "comprising," or "having," and variations thereof, identifies the presence of stated features, steps, operations, elements, components, and / or equivalents thereof, but may include one or more of the steps, operations, elements, components, and / or groups thereof. As used herein, the terms "attached," "connected," "coupled," and / or equivalents thereof are used broadly and encompass both direct and indirect attachments, connections, and couplings. Furthermore, "connected" and "coupled" are not limited to physical or mechanical connections or couplings, but can include direct or indirect electrical connections or couplings. Unless otherwise defined, all terms (including technical and scientific terms) used herein have the same meaning as commonly understood by one of ordinary skill in the art to which this invention belongs. Terms, such as those defined in commonly used dictionaries, should be interpreted to have a meaning consistent with the relevant technology and the context of this disclosure, and should not be interpreted in an idealized or overly formal sense unless explicitly defined herein. It is understood that numerous techniques and processes are disclosed in the description of the present invention. Each of these has distinct advantages, and each can be used with one or more, or in some cases all, of the other disclosed technologies. Therefore, for the sake of clarity, this description will refrain from unnecessarily repeating all possible combinations of individual steps. Nevertheless, the specification and claims should be read with the understanding that all such combinations are within the scope of the present invention and claims. A novel straddle-type vehicle is described herein. In the following description, for purposes of explanation, numerous specific details are set forth to provide a thorough understanding of the present invention.However, it will be apparent to one skilled in the art that the present invention may be practiced without these specific details. The present disclosure is to be considered as an example of the present invention and is not intended to limit the invention to the specific embodiments illustrated by the following drawings or description.

[0047] A straddle-type vehicle or straddled vehicle is a vehicle in which a driver sits astride a saddle. A straddle-type vehicle is configured so that the vehicle's posture is controlled by the driver's weight shift while traveling. Examples of straddle-type vehicles include scooter-type, moped-type, off-road-type, and on-road-type motorcycles. Furthermore, a straddle-type vehicle is not limited to motorcycles, but may also be, for example, a three-wheeled or four-wheeled buggy known as an ATV (All Terrain Vehicle), a snowmobile, or the like. A straddle-type vehicle is, for example, a leaning vehicle that turns in a leaning position. A leaning vehicle leans toward the center of a turn when turning. A leaning vehicle is, for example, a motorcycle or a tricycle. A straddle-type vehicle in the present disclosure is a vehicle driven by the output of an engine. A straddle-type vehicle does not include, for example, a bicycle. A leaning vehicle leans toward the center of a curve through operations including the driver's weight shift. Since the attitude of a saddle-type vehicle is controlled by the driver, it is preferable that the saddle-type vehicle be as small and light as possible.

[0048] The engine is an internal combustion engine. The engine may be, for example, a single-cylinder engine or an engine with multiple cylinders. The engine may be, for example, a four-stroke engine or a two-stroke engine. The saddle-ride type vehicle engine is an engine mounted on the saddle-ride type vehicle.

[0049] A drive wheel is a wheel that drives a saddle-riding vehicle. A saddle-riding vehicle may also have wheels other than drive wheels. A saddle-riding vehicle may have, for example, front wheels and rear wheels. In this case, the drive wheels may be rear wheels, front wheels, or both front and rear wheels.

[0050] The high-voltage power supply system is a system that transmits a high voltage. The high voltage is a voltage higher than the low voltage of the low-voltage power supply system. When a saddle-ride type vehicle has a system that transmits a high voltage and a system that transmits a low voltage, the system that transmits the high voltage is the high-voltage power supply system. The high voltage in the high-voltage power supply system means the voltage when at least the engine is in combustion operation. When the engine is stopped, the voltage in the high-voltage power supply system may be a low voltage including zero. The high voltage in a saddle-ride type vehicle is, for example, a voltage exceeding 24 V. In this case, the low voltage is a voltage equal to or less than 24 V. The high voltage may be, for example, a voltage exceeding 12 V. In this case, the low voltage is a voltage equal to or less than 12 V. If the high voltage in a saddle-type vehicle does not exceed, for example, 60 V, the saddle-type vehicle operates within the "extra low voltage (ELV)" or "safety extra low voltage (SELV)" range defined in the IEC 60950 standard of the International Electrotechnical Commission (IEC). In this case, the level of insulation in the power supply system is sufficient within the "operational insulation" range, allowing the wiring area to be reduced in size. However, the high voltage in a saddle-type vehicle is not particularly limited and may be, for example, 60 V or higher.

[0051] Secondary batteries and capacitors are devices that charge and discharge. Secondary batteries are storage batteries. Secondary batteries charge and discharge through chemical reactions at the electrodes. Secondary batteries charge and discharge through oxidation and reduction reactions at the electrodes. Secondary batteries store charged power as chemical energy. Secondary batteries convert stored chemical energy into electrical energy. Capacitors charge and discharge without chemical reactions at the electrodes. Capacitors store supplied power as an electric charge.

[0052] A permanent magnet motor generator is a rotating electric machine that combines the functions of a motor and a generator. A permanent magnet motor generator generates a magnetic field using permanent magnets. This does not include induction machines or alternators, which generate a magnetic field using electromagnets. A permanent magnet motor generator is, for example, an outer rotor type. However, the permanent magnet motor generator is not particularly limited and may be, for example, an inner rotor type. A permanent magnet motor generator is, for example, a surface permanent magnet motor (SPM). However, the permanent magnet motor generator is not particularly limited and may be, for example, an interior permanent magnet motor (IPM). A first permanent magnet motor generator having magnetic poles more than two-thirds the number of teeth is, for example, a permanent magnet motor generator having magnetic poles equal to or greater than four-thirds the number of teeth. Such a permanent magnet motor generator is, for example, a permanent magnet motor generator having magnetic poles equal to four-thirds the number of teeth. However, the relationship between the number of teeth and the number of magnetic poles of a permanent magnet motor generator is not particularly limited as long as the number of magnetic poles is greater than two-thirds the number of teeth. Examples of such relationships include configurations in which the number of magnetic poles is 5 / 6, 8 / 9, 11 / 12, 13 / 12, and 14 / 12 relative to the number of teeth. When the number of magnetic poles is greater than 2 / 3 of the number of teeth, the angular velocity ω increases, resulting in a large reluctance at high rotation speeds. This effectively suppresses voltage fluctuations through field-weakening control. For example, when the number of magnetic poles is a multiple of 2, such as when the number of magnetic poles is 4 / 3 of the number of teeth, circumferentially aligned magnetic pole pairs are easily formed. Furthermore, when the number of teeth is a multiple of 3, the first permanent magnet motor-generator can operate with high efficiency using a three-phase drive current. When the number of magnetic poles is 4 / 3 or less of the number of teeth, sufficient magnetic flux density can be maintained in each magnetic pole while maintaining the size and weight of the permanent magnet motor-generator.

[0053] The rotating shaft on which the rotor is provided, i.e., the rotating shaft that rotates coaxially with and at the same speed as the crankshaft, is, for example, the crankshaft itself. In this case, the rotor is provided on a part of the crankshaft. However, the rotating shaft is not particularly limited and may be, for example, a rotating shaft that is separate from the crankshaft, arranged coaxially with the crankshaft, and connected to the crankshaft by a connecting member such as a connecting sleeve. However, for example, a shaft connected to the crankshaft via a planetary gear does not rotate at the same speed as the crankshaft, and therefore does not fall under the category of a rotating shaft that is coaxial with and rotates at the same speed as the crankshaft.

[0054] A turbocharger is a device that uses the engine's exhaust gas as a power source to supercharge the engine. An electric turbocharger is a turbocharger that has a permanent magnet turbo motor generator attached to the rotating shaft of a turbine that rotates using the power of the exhaust gas and a compressor that compresses the intake air. An electric supercharger is a device that supercharges the engine by operating the compressor using a permanent magnet supercharger motor generator. An electric supercharger may operate using power other than exhaust gas in addition to the power of the permanent magnet supercharger motor generator.

[0055] The first MG control device includes, for example, a processor that executes a program and a memory that stores the program and data. The control device is realized, for example, by the processor executing a program stored in the memory. However, the structure of the control device is not particularly limited, and may be, for example, a logic circuit that processes data without relying on a processor or a program. The first MG control device may also have, for example, a function to control the engine. However, the first MG control device is not particularly limited, and may be, for example, a separate entity from the control device that controls the engine.

[0056] Field-weakening control is a method of controlling the current in a winding so that a component of current that weakens the field generated by the permanent magnet of the motor generator flows through the winding. The component of current that weakens the field corresponds to the d-axis component of the q-axis and d-axis components in a vector control method. However, the control method is not particularly limited, and any method may be used as long as the component of current that weakens the field flows through the winding as a result of the control. The control method may be, for example, phase control, in which the d-axis component is not explicitly processed and the phase of the current is directly controlled relative to the phase of the electrical angle.

[0057] The rotating shaft provided in the torque transmission path between the crankshaft and the drive wheels is, for example, an input shaft or an output shaft of a transmission. However, the rotating shaft is not particularly limited and may be a rotating shaft other than that of the transmission.

[0058] According to the present invention, it is possible to provide a saddle-type vehicle equipped with a high-voltage hybrid system that is small, lightweight, and compatible with the rotational speed range of the engine of the saddle-type vehicle.

[0059] Fig. 1 is a diagram illustrating a saddle-ride type vehicle according to a first embodiment; Fig. 2 is a chart schematically illustrating the operation of field-weakening control in the first permanent magnet motor generator shown in Fig. 1; Fig. 3 is a block diagram illustrating a second embodiment, which is a block diagram showing the flow of current in the high-voltage hybrid system shown in Fig. 1; Fig. 4 is a block diagram illustrating a third embodiment; Fig. 5 is a block diagram illustrating a fifth embodiment; Fig. 6 is a block diagram illustrating a sixth embodiment;

[0060] Hereinafter, a saddle-type vehicle according to an embodiment will be described with reference to the drawings. Note that the embodiment described below is merely an example. The present invention should not be construed as being limited in any way by the embodiment described below.

[0061] [First Embodiment] Fig. 1 is a diagram illustrating a saddle-ride type vehicle according to a first embodiment. Part (a) of Fig. 1 is a schematic side view of the saddle-ride type vehicle. Part (b) of Fig. 1 is a block diagram illustrating a schematic configuration of a high-voltage hybrid system for the saddle-ride type vehicle. Part (c) of Fig. 1 is a side view showing a detailed configuration example of the first permanent magnet motor generator shown in part (b) of Fig. 1. Part (d) of Fig. 1 is a block diagram showing an equivalent circuit of windings in the first permanent magnet motor generator. Part (e) of Fig. 1 is a vector diagram illustrating the operation of field-weakening control. Part (f) of Fig. 1 is a graph showing reluctance characteristics versus rotational speed. Part (g) of Fig. 1 is a graph showing field-weakening current characteristics versus rotational speed.

[0062] The straddle-type vehicle 10 shown in FIG. 1 includes an engine (EG) 11 , drive wheels 12 a , a high-voltage power supply system 13 , a first permanent magnet motor generator 14 , and a first MG control unit (MGCU) 15 .

[0063] The engine 11 has a crankshaft 11a. The engine 11 generates power by combusting an air-fuel mixture containing air and fuel. The engine 11 outputs power as rotational torque. The engine 11 outputs torque via the crankshaft 11a. The drive wheels 12a drive the saddle-riding vehicle 10. The saddle-riding vehicle 10 has multiple wheels 12a, 12b. The wheel 12a functions as the drive wheel 12a. At least a portion of the torque output from the engine 11 is mechanically transmitted to the drive wheel 12a. The high-voltage power supply system 13 supplies electricity at a high voltage Vhigh that is higher than the low voltage Vlow of the low-voltage power supply system 17. No battery is connected to the high-voltage power supply system 13. The saddle-riding vehicle 10 does not have a battery that operates at the high voltage Vhigh. In the example shown in the figure, the low-voltage power supply system 17 is connected to the high-voltage power supply system 13 via a DC-DC converter 18. The high voltage Vhigh of the high-voltage power supply system 13 is converted to a low voltage Vlow by a DC-DC converter 18 and supplied to a low-voltage power supply system 17. A low-voltage device 19 that operates on the low voltage Vlow is connected to the low-voltage power supply system 17. A low-voltage battery 22 that operates on the low voltage Vlow is also connected to the low-voltage power supply system 17.

[0064] The first permanent magnet motor generator 14 is electrically connected to the high-voltage power supply system 13. More specifically, the first permanent magnet motor generator 14 is electrically connected to the high-voltage power supply system 13 via a first MG control unit (MGCU) 15. The first permanent magnet motor generator 14 applies torque to the drive wheels 12a by powering. More specifically, the first permanent magnet motor generator 14 applies torque to the crankshaft 11a by powering. For example, the first permanent magnet motor generator 14 assists the engine 11 in traveling by powering. The first permanent magnet motor generator 14 also receives torque from the engine 11 or the drive wheels 12a to generate electricity. The first MG control unit 15 controls the powering and power generation of the first permanent magnet motor generator 14. The saddle-ride type vehicle 10 is a hybrid vehicle. The saddle-ride type vehicle 10 is equipped with a high-voltage hybrid system HV. The engine 11 , the drive wheels 12 a , the high-voltage power supply system 13 , the first permanent magnet motor generator 14 , and the first MG control device 15 are included in a high-voltage hybrid system HV of the saddle-ride type vehicle 10 .

[0065] The saddle-ride type vehicle 10 further includes a first power transfer device 161. The first power transfer device 161 is electrically connected to the high-voltage power supply system 13 without being connected to a battery that operates at the high voltage Vhigh. In this embodiment, the first power transfer device 161 is, for example, a permanent magnet turbo motor generator (eTC) 161 of the electric turbocharger 16. In this embodiment, the first power transfer device 161 is also referred to as a permanent magnet turbo motor generator 161. The electric turbocharger 16 is a device that uses the exhaust gas of the engine 11 as a power source to supercharge the engine 11. The electric turbocharger 16 includes the permanent magnet turbo motor generator (eTC) 161. The permanent magnet turbo motor generator 161 is provided on a rotating shaft of a turbine (not shown) that rotates using the force of the exhaust gas and a compressor (not shown) that compresses intake air. The first power transfer device 161 also includes a control unit (CU). For example, the electric turbocharger 16 serving as the first power transfer device 161 also includes a turbo control unit (eTCCU) 162 that controls the permanent magnet turbo motor generator 161. More specifically, the first power transfer device 161 is electrically connected to the high-voltage power supply system 13 via the turbo control unit 162.

[0066] As shown in part (c) of Fig. 1, the first permanent magnet motor generator 14 in the saddle-ride type vehicle 10 includes a stator 141 and a rotor 142. The stator 141 has a plurality of teeth 141T arranged in the circumferential direction, i.e., the rotational direction of the rotor 142, and windings 141W wound around each of the plurality of teeth 141T. More specifically, the plurality of teeth 141T are arranged so as to be separated by slots 141S.

[0067] The rotor 142 is provided on a rotating shaft that is coaxial with and rotates at the same speed as the crankshaft 11a. In this embodiment, the rotating shaft that is coaxial with and rotates at the same speed as the crankshaft 11a is the crankshaft 11a. The rotor 142 is mechanically connected to an end of the crankshaft 11a. In other words, the first permanent magnet motor-generator 14 is connected to an end of the crankshaft 11a. The rotor 142 has magnetic poles 142a that are greater than two-thirds the number of teeth 141T. In this embodiment, the rotor 142 has magnetic poles 142a that are four-thirds the number of teeth 141T. The magnetic poles 142a are arranged side by side in the rotational direction. The magnetic poles 142a are made of permanent magnets. In the example shown in the figure, a structure is shown in which the same number of permanent magnets as the magnetic poles 142a are arranged circumferentially. However, the structure of the magnetic poles 142a is not particularly limited, and may be, for example, a structure magnetized so that multiple magnetic poles 142a are generated in one cylindrical permanent magnet, or a structure magnetized so that multiple magnetic poles 142a are generated in each of a permanent magnet shaped like a cylinder divided into two or three blocks.

[0068] The first permanent magnet motor generator 14 is electrically connected to a permanent magnet turbo motor generator 161, which is a first power exchange device, via a first MG control device 15. The first MG control device 15 performs power running and power generation control, including field weakening control. The first permanent magnet motor generator 14 exchanges power with the permanent magnet turbo motor generator 161 via the first MG control device 15 without going through a battery.

[0069] In the first permanent magnet motor-generator 14 having magnetic poles 142a that are more than two-thirds the number of teeth 141T, the angular velocity ω in electrical angle is greater than the mechanical rotational speed of the rotor 142, compared to, for example, a case in which the number of magnetic poles 142a is two-thirds or less of the number of teeth 141T. The mechanical rotational speed is the number of rotations per unit time of the rotor 142. In contrast, the angular velocity in electrical angle is the rotation angle based on the repetition period of a pair of magnetic poles 142a passing near one tooth 141T.

[0070] The first MG control device 15 performs field weakening control on the first permanent magnet motor generator 14, which rotates at the same speed as the engine 11 of the saddle-ride type vehicle 10 and has a rotor 142 with magnetic poles 142a that are more than two-thirds the number of teeth 141T, using a high voltage Vhigh that is higher than the low voltage of the low-voltage battery 22 as a power source. As a result, the first MG control device 15 increases the amount of voltage suppression by field weakening control due to an increase in reluctance Lω caused by an increase in the magnetic poles 142a of the first permanent magnet motor generator 14, and performs field weakening control using the high voltage Vhigh as a power source to overcome the reluctance Lω that increases in the high rotation speed range of the engine 11 of the saddle-ride type vehicle 10 and supply a current component of the field weakening control to the winding 141W.

[0071] As shown in the equivalent circuit of part (d) of FIG. 1 , the winding 141W electrically includes an AC voltage source 141A, an inductor 141B, and a resistor 141R. The induced voltage E output by the AC voltage source 141A depends on the angular velocity ω. More specifically, the induced voltage E depends on the product of the angular velocity ω and the magnetic flux φ mainly interlinking with the winding 141W. The inductance L of the inductor 141B mainly depends on the magnetic flux interlinking with the winding 141W. The product L·ω of the angular velocity ω and the inductance L is the reluctance of the winding 141W. The reluctance is expressed as L·ω or Lω. The resistance value R of the resistor 141R is the winding resistance. The impedance Z of the winding 141W is roughly expressed as ((Lω)^2 + R^2)^1 / 2.

[0072] In the vector diagram of part (e) of Fig. 1, Vhigh represents the magnitude of the high voltage of the high-voltage power supply system 13. E represents the induced electromotive force. Id represents the d-axis current component, which is the field-weakening current. Iq represents the q-axis current component.

[0073] The induced voltage E depends on the product of the angular velocity ω and the magnetic flux φ interlinked mainly with the winding 141W, and therefore increases as the mechanical rotation speed of the first permanent magnet motor-generator 14 increases. The voltage output from the first permanent magnet motor-generator 14, i.e., the terminal voltage, is the result of the induced voltage E being affected by the current flowing through the winding 141W, i.e., the current flowing through the inductor 141B and the resistor 141R. The current flowing through the winding 141W includes a field-weakening current Id. The field-weakening current Id generates a magnetic flux oriented along the magnetic flux generated by the magnetic pole 142a and is also referred to as the d-axis current Id. In contrast, the q-axis current Iq generates a magnetic flux perpendicular to the field-weakening current Id in the vector diagram. The q-axis current generates a magnetic flux perpendicular to the magnetic flux generated by the magnetic pole 142a and is a current for directly controlling the torque of the first permanent magnet motor-generator 14. The induced electromotive force E is suppressed by the voltage drops Iq·R and Iq·Lω caused by the q-axis current Iq, and the voltage drops Id·R and Id·Lω caused by the field-weakening current Id. The q-axis current Iq is a main factor in generating torque of the first permanent magnet motor-generator 14, for example, and varies depending on the operating status of the first power transfer device 161 and the torque of the first permanent magnet motor-generator 14. For example, when the q-axis current Iq corresponding to the operating status of the first power transfer device 161 is small, suppression by the q-axis current Iq does not function. Therefore, suppression of the induced electromotive force E in the high rotation speed range is controlled particularly by the field-weakening current (d-axis current) Id by the field-weakening control of the first MG control device 15. In particular, the induced electromotive force E is suppressed by Id·Lω.

[0074] In the first permanent magnet motor generator 14 having magnetic poles 142a that are more than 2 / 3 of the number of teeth 141T, the angular velocity ω in electrical angle relative to the mechanical rotational speed of the rotor 142 is larger than in a case where the number of magnetic poles is less than 2 / 3 of the number of teeth, for example.

[0075] Part (f) of Fig. 1 shows the reluctance Lω in this embodiment and the reluctance (Lω)' in a comparative example in which the number of magnetic poles is less than two-thirds the number of teeth. As shown in part (f) of Fig. 1, when the number of magnetic poles 142a is more than two-thirds the number of teeth 141T, the reluctance Lω in the suppression component L·ω·Id by field-weakening control is larger than the reluctance (Lω)' when the number of magnetic poles is smaller (Y1 in part (f) of Fig. 1). Therefore, in the first permanent magnet motor-generator 14 in which the number of magnetic poles 142a is more than two-thirds the number of teeth 141T, the amount of suppression of terminal voltage by field-weakening control is large.

[0076] Part (g) of FIG. 1 shows the field weakening current Id in this embodiment and, as a comparative example, the field weakening current Id′ when controlled using the low voltage Vlow as a power source, as indicated by dashed lines. The field weakening current Id is a current component controlled by the first MG control device 15. The first MG control device 15 controls the field weakening current Id to a target value corresponding to the required amount of suppression. The field weakening current Id flows against the impedance Z of the winding 141W. As described above, the reluctance L·ω included in the impedance Z of the winding 141W increases according to the angular velocity ω. Within the controllable range, the control device controls the field weakening current Id to a target value corresponding to the suppression, regardless of changes in the impedance Z. For example, the control device performs control via the duty ratio of the on-time as a current command value.

[0077] For example, as shown by the dashed line in part (g) of FIG. 1, the field-weakening current Id' is controlled to a target value corresponding to the suppression of an increase in the induced electromotive force as the rotation speed N increases. However, once a control command value such as the duty ratio reaches its upper limit in the high rotation speed range, it cannot be increased any further. The current Id'max at the upper limit of the command value is based on the low voltage Vlow, which is the power supply voltage, and the impedance Z. If the rotation speed increases after the command value reaches its upper limit, the impedance Z increases while the command value remains at the upper limit.

[0078] The control device of this embodiment performs field-weakening control using high voltage Vhigh as a power source, thereby increasing the maximum value Idmax of field-weakening current Id that can be flowed by control, for example, as shown by the solid line in part (g) of Fig. 1. Therefore, the field-weakening current Id can be controlled to reach a target value, overcoming a large impedance Z resulting from a larger reluctance L·ω. In other words, even if the number of magnetic poles 142a is greater than two-thirds of the number of teeth 141T, resulting in a large reluctance L·ω, the field-weakening current Id in the high rotation speed range of the engine 11 of the saddle-ride type vehicle 10 can be maintained at the target value (arrow Y2).

[0079] In this way, by performing field-weakening control using a high voltage as a power source on the first permanent magnet motor-generator 14, which has more than two-thirds the number of magnetic poles 142a than the number of teeth 141T, greater voltage suppression can be achieved through field-weakening control, and a synergistic effect is achieved in which this voltage suppression can be exerted at higher rotational speeds of the engine 11 (the increase amount and increasing rotational speed range of the arrow Y1). This allows voltage fluctuations to be suppressed over a wide rotational speed range of the engine 11 of the saddle-riding vehicle 10, from low to high rotational speeds. This suppresses changes in the voltage supplied from the permanent magnet motor-generator 14 to the high-voltage power supply system 13 via the first MG control device 15 in response to changes in rotational speed. This makes it possible to supply a high voltage with suppressed fluctuations over a wide rotational speed range of the engine 11 of the saddle-riding vehicle 10, without providing a high-voltage battery in the high-voltage power supply system 13 or a reduction mechanism such as a belt or chain in the engine 11. Therefore, in the saddle-ride type vehicle 10 of this embodiment, a synergistic effect in which greater voltage suppression is exerted at higher rotational speeds by the field-weakening control makes it possible to suppress voltage fluctuations over a wide rotational speed range, including the high rotational speed range of the engine 11 of the saddle-ride type vehicle 10. As a result, a high-voltage hybrid system HV that is small, lightweight, and compatible with the rotational speed range of the engine 11 of the saddle-ride type vehicle 10 can be realized.

[0080] The effect of field weakening control using a high voltage as a power source for the first permanent magnet motor generator 14, which has magnetic poles 142a that are more than two-thirds the number of teeth 141T, can be achieved in both power generation and power running.

[0081] Figure 2 is a chart that schematically illustrates the effect of field-weakening control in the first permanent magnet motor generator shown in Figure 1. Part (a) of Figure 2 illustrates the maximum output torque characteristics and output power characteristics versus rotational speed during power running. Part (b) of Figure 2 illustrates the output power characteristics versus rotational speed during power generation. The output power of the motor generator during power running is mechanical, and the output power during power generation is electrical. The motor generator is a device that converts mechanical power and electrical power into each other.

[0082] First, with reference to part (a) of FIG. 2, an example of the characteristics during power running when the first permanent magnet motor generator 14 functions as a motor will be described.

[0083] In this embodiment, the first MG control device 15 performs field-weakening control. In the field-weakening control, the first MG control device 15 passes a current through the winding 141W to generate a magnetic field in the opposite direction to the magnetic field caused by the magnetic pole 142a, which generates the induced electromotive force. This is equivalent to a decrease in the magnetic force of the magnetic pole 142a. As a result, at the maximum output rotation speed NmaxP of the engine 11, a larger current that contributes to torque can be passed through the winding 141W. Note that the maximum output rotation speed NmaxP is the rotation speed at which the maximum output of the engine 11 can be obtained, and is one index representing the dynamic range of the rotation speed of the engine 11. The upper limit rotation speed Na of the engine 11 is even greater than the maximum output rotation speed NmaxP.

[0084] More specifically, the first MG control device 15 applies a d-axis current that contributes to the reverse magnetic flux as field-weakening control. The upper right portion of part (a) of Figure 2 shows a voltage vector diagram illustrating the voltage relationship during power running at the maximum output rotation speed NmaxP of the engine 11.

[0085] Through field-weakening control, the magnitude of the voltage Vt at the output switching unit of the first MG control device 15 is equal to the magnitude of the high voltage Vhigh of the high-voltage power supply system 13. Specifically, the magnitude of the voltage Vt obtained by combining the induced electromotive force E, the voltage drops Iq·R and Iq·Lω of the q-axis current Iq, and the voltage drops Id·R and Id·Lω of the field-weakening current Id, is equal to the magnitude of the high voltage Vhigh of the high-voltage power supply system 13. Here, R represents the resistance of the winding 141W, and L represents the inductance of the winding 141W. In this case, at the maximum output rotation speed NmaxP, the first MG control device 15 can use the voltage of the high-voltage power supply system 13 to cause the first permanent magnet motor-generator 14 to output torque that rotates the crankshaft 11a. In the example shown in the figure, the first permanent magnet motor-generator 14 can output power for power running even at a rotation speed Na that exceeds the maximum output rotation speed NmaxP of the engine 11. The number of magnetic poles 142a in the first permanent magnet motor-generator 14 is more than two-thirds the number of teeth 141T. Therefore, the angular velocity ω of the first permanent magnet motor-generator 14, based on the electrical angle of the starter-generator, is greater than, for example, a configuration having magnetic poles equal to or less than two-thirds the number of teeth 141T. This results in a high field-weakening effect. Furthermore, because the number of magnetic poles 142a is more than two-thirds the number of teeth 141T, the size of the magnetic poles 142a themselves is small. Therefore, the magnetic flux resulting from the magnetic poles 142a is easily weakened by the magnetic field of the winding 141W through which the d-axis current flows. Therefore, at the maximum output rotation speed NmaxP, the output torque Ta of the first permanent magnet motor-generator 14 is greater than the output torque Tc of a configuration having magnetic poles equal to or less than two-thirds the number of teeth 141T.

[0086] The output power Pma of the first permanent magnet motor-generator 14 depends on the product of the output torque and the rotational speed. The output power Pma of the first permanent magnet motor-generator 14, which is field-weakening controlled, can be obtained even at the maximum output rotational speed NmaxP. Therefore, the first permanent magnet motor-generator 14 receives power from the first power transfer device 16 via the high-voltage power supply system 13, and can provide sufficient driving force to the crankshaft 11a over a wide range of rotational speeds of the engine 11, including the maximum output rotational speed NmaxP. Furthermore, the first permanent magnet motor-generator 14 can absorb the power generated by the first power transfer device 16 over a wide range of rotational speeds of the engine 11, without using a secondary battery.

[0087] Next, an example of the characteristics when the first permanent magnet motor-generator 14 functions as a generator and generates power will be described with reference to part (b) of Fig. 2. The solid line Pma in part (b) of Fig. 1 represents the output power. Power generation by the first permanent magnet motor-generator 14 is affected by the reluctance L·ω of the winding 141W.

[0088] The first MG control device 15 causes the first permanent magnet motor-generator 14 to generate power while performing field-weakening control using a high voltage as a power source. The graph of the output power Pga during power generation is substantially symmetrical to part (a) of FIG. 2 . That is, at the maximum output rotational speed NmaxP, the output power Pga of the first permanent magnet motor-generator 14 under field-weakening control is greater than, for example, the output power without field-weakening control. Accordingly, the output power Pga of the first permanent magnet motor-generator 14 can output power exceeding the maximum power of the first power transfer device 16 over a wide range of rotational speeds including the maximum output rotational speed NmaxP. Therefore, the first permanent magnet motor-generator 14 can supply sufficient power for the operation of the first power transfer device 16 via the high-voltage power supply system 13.

[0089] The d-axis current and q-axis current described above can be easily controlled explicitly and independently by adopting vector control as the control method for the first MG control device 15. However, there are no particular limitations on the control method for implementing field weakening in the first MG control device 15. Field weakening control can be implemented by adjusting the timing at which current is received by the windings 141W of each phase.

[0090] According to this embodiment, the first permanent magnet motor-generator 14 can be operated over a wide rotational speed range, from low to high rotational speeds. The first permanent magnet motor-generator 14 can operate over a wide rotational speed range, including the maximum output rotational speed NmaxP. According to this embodiment, fluctuations in the generated voltage can be suppressed over a wide rotational speed range, from low to high rotational speeds, of the engine 11 of the saddle-riding vehicle 10. As a result, changes in the voltage supplied from the first permanent magnet motor-generator 14 to the high-voltage power supply system 13 via the first MG control device 15 in response to changes in rotational speed are suppressed. Therefore, a high voltage with suppressed fluctuations can be supplied to the engine 11 of the saddle-riding vehicle 10 over a wide rotational speed range, without providing a high-voltage battery in the high-voltage power supply system 13 or a reduction mechanism such as a belt or chain in the engine 11. Therefore, in the saddle-ride type vehicle 10 of this embodiment, greater voltage suppression by the field-weakening control is exerted at higher rotation speeds, resulting in a synergistic effect that makes it possible to suppress voltage fluctuations over a wide rotation speed range, including the high rotation speed range, of the engine 11 of the saddle-ride type vehicle 10. As a result, the high-voltage hybrid system HV is small and lightweight, and can accommodate the rotation speed range of the engine 11 of the saddle-ride type vehicle 10.

[0091] The first power transfer device according to this embodiment is a permanent magnet turbo motor generator 161 provided in the electric turbocharger 16. For example, when the engine 11 operates at high speed, the permanent magnet turbo motor generator 161 generates electricity. The first permanent magnet motor generator 14 receives the electric power generated by the permanent magnet turbo motor generator 161 and powers the first permanent magnet motor generator 14, applying torque to the crankshaft 11a.

[0092] According to this embodiment, the power generated by the first permanent magnet motor generator 14 can be used to increase the capacity of the electric turbocharger 16. This makes it possible to increase the capacity of the engine 11 or reduce the size of the engine 11, for example.

[0093] [Example of First Embodiment] Fig. 3 is a block diagram showing a current flow in the high-voltage hybrid system shown in Fig. 1. Part (a) of Fig. 3 shows an electric turbocharger assist state, and part (b) of Fig. 3 shows an exhaust energy recovery state.

[0094] As shown in part (a) of FIG. 3 , when an acceleration request is input while the engine 11 is operating, high-voltage electric power is supplied from the first permanent magnet motor generator 14 to the electric turbocharger 16 via the first MG control device 15 and the high-voltage power supply system 13. This electrically assists the operation of the electric turbocharger 16. This electrical assistance can achieve higher responsiveness of the supercharging function. As shown in part (b) of FIG. 3 , for example, when the engine 11 has a high output, the electric turbocharger 16 is driven by the exhaust gas from the engine 11. This causes the permanent magnet turbo motor generator 161 to generate electricity. The first permanent magnet motor generator 14 receives the electric power generated by the permanent magnet turbo motor generator 161 and applies torque to the crankshaft 11 a. In other words, the first permanent magnet motor generator 14 can assist the engine 11 without a secondary battery that operates at high voltage. This not only eliminates the need for a secondary battery, but also allows the engine 11 to be made smaller. Therefore, the high-voltage hybrid system HV provided in the saddle-type vehicle 10 can be made smaller and lighter while suppressing a decrease in the torque or power transmitted to the drive wheels 12a.

[0095] [Second embodiment] Fig. 4 is a block diagram showing a second embodiment, in which part (a) of Fig. 4 is a block diagram showing the current in the starting state, and part (b) of Fig. 4 is a block diagram showing the current in the charging state.

[0096] The saddle-type vehicle 10 shown in Figure 4 includes a starter motor 21 that starts the engine 11. The starter motor 21 drives, for example, the crankshaft 11a during starting. The starter motor 21 operates on the low voltage of the low-voltage power supply system 17 to start the engine 11 without powering the first permanent magnet motor-generator 14.

[0097] The above points are the main differences from the first embodiment. Hereinafter, the differences from the first embodiment will be mainly described, and the same reference numerals will be used to denote elements common to the first embodiment, and description thereof will be omitted.

[0098] The saddle-ride type vehicle 10 of this embodiment includes a starter motor 21 that operates at a low voltage and starts the engine 11. Therefore, the engine 11 can be started even if the first permanent magnet motor-generator 14 does not have the function of starting the engine 11. For example, as shown in part (a) of FIG. 4 , when starting the engine 11, current flows from the low-voltage battery 22 to the starter motor 21 to supply power. The starter motor 21 starts the engine 11 using power from the low-voltage battery 22. After the engine 11 starts, the first permanent magnet motor-generator 14 is driven by the engine 11 to generate electricity. As shown in part (b) of FIG. 4 , the current generated by the first permanent magnet motor-generator 14 flows from the high-voltage power supply system 13 to the low-voltage power supply system 17 via the DC-DC converter 18. The DC-DC converter 18 converts the high voltage generated by the first permanent magnet motor-generator 14 to a low voltage. The current supplied via the DC-DC converter 18 is stored in the low-voltage battery 22.

[0099] Generally, a motor that starts the engine 11 outputs a torque large enough to start the engine 11, and therefore, for example, it is often necessary to strengthen the magnetic flux of the magnet. However, in this embodiment, the starting function is omitted from the first permanent magnet motor-generator 14, which increases the structural freedom, for example, by allowing magnets with weak magnetic flux to be used as the magnets that make up the magnetic poles 142a. Therefore, the first permanent magnet motor-generator 14 can be configured to output power corresponding to the high-voltage power supply system 13 over a range that is closer to the dynamic range of the rotational speed of the engine 11. As a result, the high-voltage hybrid system HV included in the saddle-ride type vehicle 10 can be made smaller and lighter.

[0100] Third Embodiment FIG. 5 is a block diagram showing a third embodiment.

[0101] The saddle-ride type vehicle 10 shown in Figure 5 includes a capacitor 31 as a first power transfer device. The capacitor 31 stores electric power in the form of an electric charge. The capacitor 31 outputs the stored electric power in the form of an electric charge. The first permanent magnet motor generator 14 receives electric power from the capacitor 31 and powers the first permanent magnet motor generator 14, thereby applying torque to the crankshaft 11a. When the first permanent magnet motor generator 14 generates electric power, the electric power output from the first permanent magnet motor generator 14 is stored in the capacitor 31.

[0102] The above points are the main differences from the first embodiment. Hereinafter, the differences from the first embodiment will be mainly described, and the same reference numerals will be used to denote elements common to the first embodiment, and description thereof will be omitted.

[0103] Unlike a secondary battery, the capacitor 31 charges and discharges without chemical reactions at the electrodes. Therefore, it can be made smaller and lighter than a secondary battery that can input and output the same current at the same voltage. According to this embodiment, the first permanent magnet motor-generator 14 receives power from the capacitor 31 instead of the secondary battery, and applies torque to the crankshaft 11a. Therefore, the conditions under which torque can be applied to the crankshaft 11a can be expanded, while the high-voltage hybrid system HV included in the saddle-type vehicle 10 can be made smaller and lighter.

[0104] Fourth Embodiment FIG. 6 is a block diagram showing a fourth embodiment.

[0105] The saddle-type vehicle 10 shown in FIG. 6 includes an electric supercharger 46 instead of the electric turbocharger 16. The first electric power transfer device in this embodiment is a permanent magnet supercharger motor generator (eSC) 461 provided in the electric supercharger 46. In this embodiment, the first electric power transfer device may also be referred to as the permanent magnet supercharger motor generator 461. The permanent magnet supercharger motor generator 461 is controlled by a supercharger control device 462. The permanent magnet supercharger motor generator 461 receives electric power generated by the first permanent magnet motor generator 14 to power the engine 11 and supercharge it. The first permanent magnet motor generator 14 also receives electric power generated by the permanent magnet supercharger motor generator 461 to power the engine 11 and apply torque to the crankshaft 11a.

[0106] The above points are the main differences from the first embodiment. Hereinafter, the differences from the first embodiment will be mainly described, and the same reference numerals will be used to denote elements common to the first embodiment, and description thereof will be omitted.

[0107] According to this embodiment, the power generated by the first permanent magnet motor generator 14 can increase the capacity of the electric supercharger 46. The first permanent magnet motor generator 14 can supply power to the electric supercharger 46 without a high-voltage secondary battery. This allows the engine 11 to be increased in capacity and the engine 11 to be made smaller. Furthermore, when the electric supercharger 46 decelerates, the permanent magnet supercharger motor generator 461 can generate power by utilizing the rotational inertia of the electric supercharger 46. The first permanent magnet motor generator 14 receives the power generated by the permanent magnet supercharger motor generator 461 and applies torque to the crankshaft 11a. The permanent magnet turbo motor generator 161 can assist the engine 11 without a high-voltage secondary battery. According to this embodiment, in addition to eliminating the need for a secondary battery, the engine 11 can be made smaller. Therefore, the high-voltage hybrid system HV provided in the saddle-type vehicle 10 can be made smaller and lighter while suppressing a decrease in the torque or power transmitted to the drive wheels 12a.

[0108] Fifth Embodiment FIG. 7 is a block diagram showing a fifth embodiment.

[0109] The saddle-ride type vehicle 10 shown in FIG. 7 includes a second permanent magnet motor generator 56 instead of the electric turbocharger 16. The first power transfer device in this embodiment is a second permanent magnet motor generator 561. More specifically, the second permanent magnet motor generator 561 is mechanically connected to a rotating shaft provided in a torque transmission path PT between the crankshaft 11a and the drive wheels 12a. The rotating shaft provided in the torque transmission path PT is, for example, an input shaft or output shaft of a transmission (not shown). In this embodiment, the first power transfer device may also be referred to as the second permanent magnet motor generator 561. The first permanent magnet motor generator 14 receives electric power generated by the second permanent magnet motor generator 561 and applies torque to the crankshaft 11a.

[0110] The above points are the main differences from the first embodiment. Hereinafter, the differences from the first embodiment will be mainly described, and the same reference numerals will be used to denote elements common to the first embodiment, and description thereof will be omitted.

[0111] According to this embodiment, the second permanent magnet motor generator 561 can be powered by the electric power generated by the first permanent magnet motor generator 14. The first permanent magnet motor generator 14 can supply electric power to the second permanent magnet motor generator 561 without a secondary battery that operates at high voltage. Furthermore, when the second permanent magnet motor generator 561 receives torque, the second permanent magnet motor generator 561 can generate electric power. The first permanent magnet motor generator 14 receives the electric power generated by the second permanent magnet motor generator 561 and powers the crankshaft 11a, applying torque to the crankshaft 11a. The first permanent magnet motor generator 14 can assist the engine 11 without a secondary battery that operates at high voltage. This not only eliminates the need for a secondary battery, but also allows the engine 11 to be made smaller. This allows the high-voltage hybrid system HV included in the saddle-ride type vehicle 10 to be made smaller and lighter. Furthermore, the second permanent magnet motor generator 561 can drive the drive wheels 12a, for example, from a position on a transmission path different from that of the engine 11. This allows for a higher degree of freedom in setting the running state of the saddle-ride type vehicle 10. This allows for a higher degree of freedom in setting the running state of the saddle-ride type vehicle 10, while also making the high-voltage hybrid system HV included in the saddle-ride type vehicle 10 smaller and lighter.

[0112] Sixth Embodiment FIG. 8 is a block diagram showing a sixth embodiment.

[0113] The saddle-riding vehicle 10 shown in Figure 8 includes a capacitor 31 serving as a first power transfer device. The saddle-riding vehicle 10 also includes a second power transfer device. In this embodiment, the second power transfer device is a permanent magnet turbo motor generator 161 provided in the electric turbocharger 16. The permanent magnet turbo motor generator 161 serving as the second power transfer device receives electric power from both the capacitor 31 and the first permanent magnet motor generator 14 to perform power running.

[0114] The above points are the main differences from the first embodiment. Hereinafter, the differences from the first embodiment will be mainly described, and the same reference numerals will be used to denote elements common to the first embodiment, and description thereof will be omitted.

[0115] According to this embodiment, the first permanent magnet motor generator 14 receives power from the capacitor 31, not from the secondary battery, and applies torque to the crankshaft 11a. This expands the conditions under which torque can be applied to the crankshaft 11a, while making it possible to make the high-voltage hybrid system HV included in the saddle-ride type vehicle 10 smaller and lighter. Furthermore, even if there is a period when the period when the permanent magnet turbo motor generator 161, serving as the second power transfer device, generates electricity does not overlap with the period when the first permanent magnet motor generator 14 performs power transfer, the generated electricity is temporarily stored in the capacitor 31 and then used for power transfer. Conversely, even if there is a period when the period when the first permanent magnet motor generator 14 generates electricity does not overlap with the period when the permanent magnet turbo motor generator 161, serving as the second power transfer device, performs power transfer, the generated electricity is temporarily stored in the capacitor 31 and then used for power transfer. This allows the high-voltage hybrid system HV included in the saddle-riding type vehicle 10 to be made smaller and lighter while further expanding the conditions under which torque can be applied to the crankshaft 11a. Furthermore, the permanent magnet turbo motor generator 161 serving as the second power exchange device can receive electric power from both the capacitor 31 and the first permanent magnet motor generator 14 for power running. This allows the high-voltage hybrid system HV included in the saddle-riding type vehicle 10 to be made smaller and lighter while increasing the capacity of the second power exchange device without the need for a secondary battery that functions at high voltage.

[0116] In the sixth embodiment described above, an example of the second power transfer device has been described in which the permanent magnet turbo motor generator 161 is provided in the electric turbocharger 16. However, the second power transfer device in the disclosed technology is not particularly limited, and may be, for example, at least one of a permanent magnet supercharger motor generator 461 provided in the electric supercharger 46 as shown in FIG. 6 and a second permanent magnet motor generator 561 that is separate from the first permanent magnet motor generator 14 and performs power running and generates electricity as shown in FIG.

[0117] Furthermore, the contents of the above-described embodiments can be combined in any manner. For example, the first embodiment equipped with an electric turbocharger can be combined with the electric supercharger of the fourth embodiment. Furthermore, the second permanent magnet motor-generator of the fifth embodiment can be combined. Furthermore, the starter motor of the second embodiment and a battery operating at a low voltage can be combined. Furthermore, the capacitor of the third embodiment can be combined. Furthermore, the first embodiment equipped with an electric turbocharger can be combined with the second permanent magnet motor-generator of the fifth embodiment. Furthermore, the starter motor of the second embodiment and a battery operating at a low voltage can be combined. Furthermore, the capacitor of the third embodiment can be combined. Furthermore, the fourth embodiment equipped with an electric supercharger can be combined with the second permanent magnet motor-generator of the fifth embodiment. Furthermore, the starter motor of the second embodiment and a battery operating at a low voltage can be combined. Furthermore, the capacitor of the third embodiment can be combined. The second embodiment, which includes a starter motor and a battery that operates at a low voltage, can be combined with either the capacitor of the third embodiment, the electric supercharger of the fourth embodiment, or the second permanent magnet motor generator of the fifth embodiment. The third embodiment, which includes a capacitor, can be combined with either the starter motor and a battery that operates at a low voltage of the second embodiment, the electric supercharger of the fourth embodiment, or the second permanent magnet motor generator of the fifth embodiment.

[0118] 10 saddle-ride type vehicle 11 engine 11a crankshaft 12a drive wheel 13 high-voltage power supply system 14 first permanent magnet motor generator 15 first MG control device 16 electric turbocharger 17 low-voltage power supply system 21 starter motor 31 capacitor 46 electric supercharger 56 second permanent magnet motor generator 141 stator 141T teeth 141W winding 142 rotor 142a magnetic pole 161 permanent magnet turbo motor generator (first power transfer device) 461 permanent magnet supercharger motor generator (first power transfer device) 561 second permanent magnet motor generator (first power transfer device)

Claims

1. An engine having a crankshaft and outputting torque via the crankshaft; drive wheels to which at least a portion of the torque output from the engine is mechanically transmitted and which drive a saddle-type vehicle; a high-voltage power supply system which operates at a high voltage higher than the low voltage of a low-voltage power supply system to which a low-voltage battery is connected; a first permanent magnet motor generator comprising: a stator having a plurality of teeth arranged in the circumferential direction and windings wound around each of the plurality of teeth; and a rotor having magnetic poles provided on a rotating shaft which is coaxial with and rotates at the same speed as the crankshaft, the first permanent magnet motor generator providing torque to the drive wheels by powering while receiving and sending electric power to and from the high-voltage power supply system, and generating electricity by receiving torque from the engine or the drive wheels; and a first MG control device which is not connected to a battery and is electrically connected to the high-voltage power supply system and is electrically connected to the first permanent magnet motor generator, and which controls the powering and power generation of the first permanent magnet motor generator. a first power receiving / receiving device which is any one of a capacitor for receiving and transmitting electric power, which is electrically connected to the high-voltage power supply system without being connected to a battery that functions at a high voltage, a permanent magnet turbo motor generator provided in an electric turbocharger, a permanent magnet supercharger motor generator provided in an electric supercharger, and a second permanent magnet motor generator that performs power running and generates electricity separately from the first permanent magnet motor generator, wherein the first MG control device increases an amount of voltage suppression by field weakening control due to an increase in reluctance caused by an increase in magnetic poles of the first permanent magnet motor generator, while overcoming the reluctance that increases in a high rotation range of the engine of the saddle type vehicle by field weakening control using the high voltage as a power source, and supplies a current component of the field weakening control to the windings, The first permanent magnet motor generator rotates at the same speed as the engine of the saddle-type vehicle and has a rotor with magnetic poles that are more than 2 / 3 the number of teeth, and the field-weakening control is performed using the high voltage, which is higher than the low voltage of the low-voltage battery, as a power source.

2. A saddle-ride type vehicle as described in claim 1, further comprising a starter motor that operates at the low voltage of the low-voltage power supply system to start the engine without powering the first permanent magnet motor generator, and the first MG control device performs the field-weakening control on the first permanent magnet motor generator that rotates at the same speed as the engine of the saddle-ride type vehicle and has a rotor with magnetic poles that number more than 2 / 3 of the number of teeth, using as a power source the high voltage that is higher than the low voltage of the low-voltage battery that operates the starter motor.

3. A saddle-ride type vehicle as claimed in claim 1 or 2, wherein the first power transfer device is the capacitor, the first permanent magnet motor generator receives power from the capacitor to power it and apply torque to the crankshaft, and the first MG control device performs the field-weakening control on the first permanent magnet motor generator, which rotates at the same speed as the engine of the saddle-ride type vehicle and has a rotor with magnetic poles that have more than 2 / 3 the number of teeth, using the high voltage, to which the capacitor is connected, as a power source which is higher than the low voltage of the low-voltage battery.

4. A saddle-ride type vehicle as claimed in any one of claims 1 to 3, wherein the first power transfer device is the permanent magnet turbo motor generator provided on the electric turbocharger, and the first permanent magnet motor generator receives power generated by the permanent magnet turbo motor generator to power and apply torque to the crankshaft, and the first MG control device performs the field weakening control on the first permanent magnet motor generator, which rotates at the same speed as the engine of the saddle-ride type vehicle and has a rotor with magnetic poles that are greater than 2 / 3 of the number of teeth, using the high voltage, which is higher than the low voltage of the low-voltage battery and to which the electric turbocharger is connected, as a power source.

5. A saddle-ride type vehicle as claimed in any one of claims 1 to 4, wherein the first power transfer device is the permanent magnet type supercharger motor generator provided on the electric supercharger, and the first permanent magnet type motor generator receives power generated by the permanent magnet type supercharger motor generator to power and apply torque to the crankshaft, and the first MG control device performs the field weakening control on the first permanent magnet type motor generator, which rotates at the same speed as the engine of the saddle-ride type vehicle and has a rotor with magnetic poles that are greater than 2 / 3 of the number of teeth, using the high voltage, which is higher than the low voltage of the low-voltage battery and to which the electric supercharger is connected, as a power source.

6. A saddle-ride type vehicle as claimed in any one of claims 1 to 5, wherein the first power transfer device is the second permanent magnet motor generator, the first permanent magnet motor generator receives power generated by the second permanent magnet motor generator to power the crankshaft and apply torque to the crankshaft, and the first MG control device performs the field weakening control on the first permanent magnet motor generator, which rotates at the same speed as the engine of the saddle-ride type vehicle and has a rotor with magnetic poles that have more than 2 / 3 the number of teeth, using the high voltage, which is higher than the low voltage of the low-voltage battery and to which the second permanent magnet motor generator is connected, as a power source.

7. A saddle-ride type vehicle as claimed in any one of claims 1 to 6, wherein the first power transfer device is the second permanent magnet motor generator mechanically connected to a rotating shaft provided in a torque transmission path between the crankshaft and the drive wheels, and the first permanent magnet motor generator receives power generated by the second permanent magnet motor generator and powers it to apply torque to the crankshaft, and the first MG control device performs the field-weakening control on the first permanent magnet motor generator, which rotates at the same speed as the engine of the saddle-ride type vehicle and has a rotor with magnetic poles that are greater than 2 / 3 of the number of teeth, using the high voltage, which is higher than the low voltage of the low-voltage battery and to which the second permanent magnet motor generator is connected, as a power source.

8. A saddle-ride type vehicle as claimed in any one of claims 1 to 7, further comprising a second power transfer device which is one of the permanent magnet turbo motor generator provided in the electric turbocharger, the permanent magnet supercharger motor generator provided in the electric supercharger, and the second permanent magnet motor generator which is separate from the first permanent magnet motor generator and powers and generates electricity, and the first MG control device performs the field weakening control on the first permanent magnet motor generator which rotates at the same speed as the engine of the saddle-ride type vehicle and has a rotor with magnetic poles which number more than 2 / 3 of the number of teeth, using the high voltage which is higher than the low voltage of the low voltage battery and to which the capacitor is connected as a power source.

9. A saddle-ride type vehicle as described in claim 8, wherein the second power transfer device receives power from both the capacitor and the first permanent magnet motor generator to power it, and the first MG control device performs the field-weakening control on the first permanent magnet motor generator, which rotates at the same speed as the engine of the saddle-ride type vehicle and has a rotor with magnetic poles that are greater than 2 / 3 of the number of teeth, using the high voltage, to which the capacitor is connected, as a power source which is higher than the low voltage of the low-voltage battery.

Images