Multi-phase motor driving apparatus and method of controlling multi-phase motor

Abstract

To improve torque generation efficiency of a motor with respect to a current flowing through a polyphase motor when the polyphase motor is driven in a high-speed region.SOLUTION: The polyphase motor drive device 1 includes a polyphase motor 10 having five or more phases and including stator coils 20 and terminal portions 30 provided at both ends of each of the stator coils 20, a voltage switch 41 connected between each of the terminal portions 30 of the stator coils 20 and a voltage source 50, a ground switch 42 connected between each of the terminal portions of the stator coils 20 and a ground 51, and a controller 60 that controls opening and closing of the voltage switch 41 and the ground switch 42.SELECTED DRAWING: Figure 1

Description

[Technical Field]

[0001] The present invention relates to a polyphase motor drive device and a method for controlling a polyphase motor. [Background technology]

[0002] Known conventional polyphase motors include, for example, the polyphase motor described in Patent Document 1. The polyphase motor described in Patent Document 1 performs field weakening control when the polyphase motor is driven in the high-speed range, thereby reducing the back electromotive force generated in the coils and widening the usable speed range when driven in the high-speed range. [Prior art documents] [Patent documents]

[0003] [Patent Document 1] Japanese Patent Application Laid-Open No. 2006-141095 Summary of the Invention [Problem to be solved by the invention]

[0004] When performing field-weakening control in a multi-phase motor such as that described in Patent Document 1, a current is passed through the stator coil to reduce the rotor field. However, the current passed through the stator coil for this field-weakening control is not originally a current for generating torque in the motor, which causes a problem of reduced torque generation efficiency in the motor relative to the current passed through the multi-phase motor.

[0005] The present invention has been made to solve such problems, and aims to improve the torque generation efficiency of a polyphase motor in relation to the current flowing through it when the polyphase motor is driven at high speeds. [Means for solving the problem]

[0006] In order to solve the above problems, a polyphase motor drive device according to the present invention includes a polyphase motor having five or more phases, the polyphase motor having motor coils and terminal portions provided at both ends of each motor coil, each terminal portion of each motor coil being connected to each terminal portion of a motor coil of an adjacent phase, a voltage switch portion connected between each terminal portion of each motor coil and a voltage source, a ground switch portion connected between each terminal portion of each motor coil and ground, and a control portion for controlling opening and closing of the voltage switch portion and the ground switch portion, wherein when the rotation speed of the polyphase motor is a first speed, the control portion turns on the voltage switch portion connected to at least one first terminal portion and turns off the ground switch portion, and ... at least one voltage switch portion connected to at least one first terminal portion and turns off at least one ground switch portion located at a first electrical angle difference from the at least one first terminal portion. The control is performed as follows: a voltage switch unit connected to the second terminal unit is turned off and a ground switch unit is turned on; the voltage switch unit and the ground switch unit connected to each terminal unit other than at least one first terminal unit and at least one second terminal unit are turned off; when the rotation speed of the polyphase motor is a second speed higher than the first speed, the voltage switch unit connected to at least one first terminal unit is turned on and the ground switch unit is turned off; a voltage switch unit connected to at least one third terminal unit located at a second electrical angle difference smaller than the first electrical angle difference with respect to the at least one first terminal unit is turned off and the ground switch unit is turned on; and the voltage switch unit and the ground switch unit connected to each terminal unit other than the at least one first terminal unit and at least one third terminal unit are turned off.

[0007] Furthermore, in order to achieve the above object, a method for controlling a polyphase motor according to the present invention includes a polyphase motor having five or more phases, the polyphase motor having motor coils and terminal portions provided at both ends of each motor coil, each terminal portion of each motor coil being connected to each terminal portion of a motor coil of an adjacent phase, a voltage switch portion connected between each terminal portion of each motor coil and a voltage source, a ground switch portion connected between each terminal portion of each motor coil and ground, and a control portion for controlling opening and closing of the voltage switch portion and the ground switch portion, wherein, when the rotation speed of the polyphase motor is a first speed, the control portion turns on the voltage switch portion connected to at least one first terminal portion and turns off the ground switch portion, and connects at least one second terminal portion positioned at a first electrical angle difference from the at least one first terminal portion and a second step of controlling, when the rotation speed of the polyphase motor is a second speed higher than the first speed, the control unit to turn on the voltage switch unit connected to the at least one first terminal unit and turn off the ground switch unit, turn off the voltage switch unit connected to at least one third terminal unit positioned at a second electrical angle difference smaller than the first electrical angle difference with respect to the at least one first terminal unit and turn on the ground switch unit, and turn off the voltage switch unit and the ground switch unit connected to each terminal unit other than the at least one first terminal unit and the at least one third terminal unit. [Effects of the Invention]

[0008] The polyphase motor drive device and polyphase motor drive method according to the present invention are configured to, when the rotation speed of the polyphase motor is a first speed, turn on a voltage switch unit connected to at least one first terminal unit and turn off a ground switch unit, turn off a voltage switch unit connected to at least one second terminal unit positioned at a first electrical angle difference from the at least one first terminal unit and turn on a ground switch unit, and turn off the voltage switch unit and the ground switch unit connected to each terminal unit other than the at least one first terminal unit and the at least one second terminal unit, and when the rotation speed of the polyphase motor is a second speed higher than the first speed The purpose of the present invention is to control the voltage switch unit connected to at least one first terminal unit to be on and the ground switch unit to be off, to control the voltage switch unit connected to at least one third terminal unit that is positioned at a second electrical angle difference smaller than the first electrical angle difference from the at least one first terminal unit to be off and the ground switch unit to be on, and to control the voltage switch unit and ground switch unit connected to each terminal unit other than the at least one first terminal unit and the at least one third terminal unit to be off, thereby improving the torque generation efficiency of the motor with respect to the current flowing through the multi-phase motor when the multi-phase motor is driven in a high-speed range. [Brief explanation of the drawings]

[0009] [Figure 1] FIG. 2 is a schematic diagram showing a connection state of a stator coil of a polyphase motor. DETAILED DESCRIPTION OF THE INVENTION

[0010] A multi-phase motor according to an embodiment of the present invention will now be described with reference to the accompanying drawings. FIG. 1 is a schematic diagram showing the connection state of stator coils of a multi-phase motor. The multi-phase motor 10 of this embodiment is a brushless DC motor, which is a multi-phase motor with 12 phases per two poles. This multi-phase motor 10 has a total of 12 stator coils 20, one for each phase. The stator coils 20 form a motor coil. Each stator coil 20 has terminal portions 30 at both ends, and the terminal portions 30 of each stator coil 20 are connected to the terminal portions 30 of the stator coil 20 of an adjacent phase. In other words, the stator coils 20 are connected in a delta connection. In this embodiment, the terminal portions 30 connected to each other between the stator coils 20 of adjacent phases are represented in counterclockwise order as terminal portions 30a to 30l. Furthermore, adjacent stator coils 20 have a phase angle of 30°.

[0011] A voltage switch unit 41 and a ground switch unit 42, which constitute a switching circuit 40, are connected to terminal units 30a to 30l of each stator coil 20. The voltage switch unit 41 and the ground switch unit 42 are configured by MOSFETs, which are switching elements. The terminal units 30a to 30l are connected to a voltage source 50 via the voltage switch unit 41, and to ground 51 via the ground switch unit 42. When the voltage switch unit 41 is turned on, electrical continuity is established between the terminal unit 30 and the voltage source 50, and when the ground switch unit 42 is turned on, electrical continuity is established between the terminal unit 30 and the ground 51. The voltage switch unit 41 and the ground switch unit 42 are controlled to be turned on and off by a control unit 60 connected to the gates of the MOSFETs.

[0012] For ease of explanation, FIG. 1 shows only the voltage switch unit 41 and the ground switch unit 42 connected to the terminal portions 30a, 30b, 30l of each stator coil 20 of adjacent phases, but similar voltage switch units 41 and ground switch units 42 (not shown) are connected to the terminal portions 30b to 30k.

[0013] Next, a method for controlling the polyphase motor 10 using the polyphase motor drive device 1 according to this embodiment will be described. When driving the polyphase motor 10, a motor driver circuit (not shown) supplies drive power to each stator coil 20 using PWM control. The control unit 60 also controls the connected voltage switch unit 41 and ground switch unit 42 to perform switching such that a predetermined terminal corresponding to the rotor rotation angle is connected to the voltage source 50, and a terminal located a predetermined electrical angle away from that terminal is connected to the ground.

[0014] First, with reference to Table 1, switching of the voltage switch section 41 and the ground switch section 42 connected to each of the terminal sections 30a to 30l when the polyphase motor 10 is driven in the low speed range will be described.

[0015] [Table 1]

[0016] Table 1 shows the switching states of the energized phases of terminals 30a-30l when polyphase motor 1 is driven in the low-speed range. When the rotation angle of the rotor (not shown) is 0°, control unit 60 turns on voltage switch unit 41 connected to terminal 30a and turns off ground switch unit 42, connecting terminal 30a to voltage source 50. In Table 1 and Tables 2 and 3 described later, a switching state in which voltage switch unit 41 is turned on and ground switch unit 42 is turned off to connect terminal 30a to voltage source 50 is indicated by a + sign. In Table 1 and Tables 2 and 3 described later, control unit 60 turns off voltage switch unit 41 connected to terminal 30g, which is 180° apart from terminal 30a, and turns on ground switch unit 42 to connect terminal 30g to ground 51. In Table 1 and Tables 2 and 3 described later, a switching state in which voltage switch unit 41 is turned off and ground switch unit 42 is turned on to connect terminal 30g to ground 51 is indicated by a - sign. Furthermore, the control unit 60 turns off the voltage switch unit 41 and the ground switch unit 42 connected to the terminals 30b to 30f and 30h to 30l excluding the terminal unit 30a and the terminal unit 30g, thereby disconnecting the terminals 30b to 30f and 30h to 30l from the voltage source 50 and the ground 51. In Table 1 and Tables 2 and 3 described later, such a switching state in which the voltage switch unit 41 and the ground switch unit 42 are turned off and the terminals are not connected to the voltage source 50 and the ground 51 is shown as a blank cell with no reference numeral.

[0017] Next, the control unit 60 switches on and off the voltage switch unit 41 and the ground switch unit 42 connected to each of the terminals 30a to 30l in accordance with the rotor rotation angle. When the rotor rotation angle is 30°, the control unit 60 connects the terminal 30b to the voltage source 50, connects the terminal 30h, which has an electrical angle difference of 180° with respect to the terminal 30b, to the ground 51, and switches so that the terminals 30a, 30c to 30g, and 30i to 30l other than the terminals 30b and 30h are not connected to the voltage source 50 or the ground 51.

[0018] Next, when the rotor rotation angle is 60°, the control unit 60 switches so that the terminal 30c is connected to the voltage source 50, and the terminal 30i, which has an electrical angle difference of 180° from the terminal 30c, is connected to the ground 51, and the other terminals 30a, 30b, 30d to 30h, and 30j to 30l are not connected to the voltage source 50 or the ground 51.

[0019] Next, when the rotor rotation angle is 90°, control unit 60 performs switching to connect terminal 30d to voltage source 50 and terminal 30j, which has an electrical angle difference of 180° with respect to terminal 30d, to ground 51, and not to connect the other terminals 30a to 30c, 30e to 30i, 30k, and 30l to the voltage source 50 or the ground 51. Next, when the rotor rotation angle is 120°, control unit 60 performs switching to connect terminal 30e to voltage source 50 and terminal 30k, which has an electrical angle difference of 180° with respect to terminal 30e, to ground 51, and not to connect the other terminals 30a to 30d, 30f to 30j, and 30l to the voltage source 50 or the ground 51. Next, when the rotor rotation angle is 150°, the control unit 60 switches so that the terminal 30f is connected to the voltage source 50, and the terminal 30l, which has an electrical angle difference of 180° from the terminal 30f, is connected to the ground 51, and the other terminals 30a to 30e, 30g to 30k are not connected to the voltage source 50 or the ground 51.

[0020] Next, when the rotor rotation angle is 180°, the control unit 60 performs switching so that terminal 30g is connected to the voltage source 50 and terminal 30a, which has an electrical angle difference of 180° with respect to terminal 30g, is connected to ground 51, and the other terminals 30b to 30f and 30h to 30l are not connected to the voltage source 50 or ground 51. Next, when the rotor rotation angle is 210°, the control unit 60 performs switching so that terminal 30h is connected to the voltage source 50 and terminal 30b, which has an electrical angle difference of 180° with respect to terminal 30h, is connected to ground 51, and the other terminals are not connected to the voltage source 50 or ground 51. Next, when the rotor rotation angle is 240°, the control unit 60 switches so that the terminal 30i is connected to the voltage source 50, the terminal 30c, which has an electrical angle difference of 180° from the terminal 30i, is connected to the ground 51, and the other terminals 30a, 30b, 30d to 30h, and 30j to 30l are not connected to the voltage source 50 or the ground 51.

[0021] Next, when the rotor rotation angle is 270°, control unit 60 performs switching to connect terminal 30j to voltage source 50 and terminal 30d, which has an electrical angle difference of 180° with respect to terminal 30j, to ground 51, and not to connect the other terminals 30a to 30c, 30e to 30i, 30k, and 30l to the voltage source 50 or the ground 51. Next, when the rotor rotation angle is 300°, control unit 60 performs switching to connect terminal 30k to voltage source 50 and terminal 30e, which has an electrical angle difference of 180° with respect to terminal 30k, to ground 51, and not to connect the other terminals 30a to 30d, 30f to 30j, and 30l to the voltage source 50 or the ground 51. Next, when the rotor rotation angle is 330°, the control unit 60 switches so that terminal 30l is connected to the voltage source 50, and terminal 30f, which has an electrical angle difference of 180° from terminal 30l, is connected to ground 51, and the other terminals 30a to 30e, 30g to 30k are not connected to the voltage source 50 or ground 51.

[0022] As described above, as the rotor rotation angle changes sequentially from 0° to 30°, 60°, 90°, 120°, 150°, 210°, 240°, 270°, 300°, and 330°, the control unit 60 sequentially connects terminals 30a, 30b, 30c, 30d, 30e, 30f, 30g, 30h, 30i, 30j, 30k, and 30l to the voltage source 50, sequentially connects terminals 30g, 30h, 30i, 30j, 30k, 30l, 30a, 30b, 30c, 30d, 30e, and 30f that are positioned at an electrical angle difference of 180° from the above terminals to ground 51, and sequentially switches the other terminals so that they are not connected to the voltage source 50 or ground 51. This switches the phase to which current is supplied to the stator coil 20, and drives the polyphase motor 10.

[0023] When the polyphase motor 1 is driven in the low speed range, the control unit 60 switches the phase to which current is passed in the stator coil 20 so that a terminal connected to the voltage source 50 and having an electrical angle difference of 180° is connected to the ground 51, thereby maximizing the output torque of the polyphase motor 1. Note that the number of current-carrying coils in the stator coil 20 of the polyphase motor 1 at this time is 12 in total.

[0024] Next, with reference to Table 2, switching of the voltage switch section 41 and the ground switch section 42 connected to each of the terminal sections 30a to 30l when the polyphase motor 10 is driven in the medium speed range, which is higher than the low speed range, will be described.

[0025] [Table 2]

[0026] Table 2 shows the switching state of the energized phases of terminals 30a to 30l when polyphase motor 1 is driven in the medium speed range. When the rotation angle of the rotor (not shown) is 0°, control unit 60 turns on voltage switch unit 41 connected to terminal A and turns off ground switch unit 42, connecting terminal A to voltage source 50. Control unit 60 also turns off voltage switch unit 41 connected to terminal 30a, which is at an electrical angle difference of 120° from terminal 30a, and turns on ground switch unit 42, connecting terminal 30e to ground 51. Control unit 60 also turns off voltage switch unit 41 connected to terminal 30g, which is at an electrical angle difference of 180° from terminal 30a, and turns on ground switch unit 42, connecting terminal 30g to ground 51. Furthermore, the control unit 60 turns on the voltage switch unit 41 connected to the terminal 30k, which has an electrical angle difference of 120° with respect to the terminal 30g, and turns off the ground switch unit 42, thereby connecting the terminal 30k to the voltage source 50. Furthermore, the control unit 60 turns off the voltage switch unit 41 and the ground switch unit 42 connected to the terminals 30b to 30d, 30f, 30h to 30j, and 30l excluding the terminals 30a, 30e, 30g, and 30k, thereby disconnecting the terminals 30b to 30d, 30f, 30h to 30j, and 30l from the voltage source 50 and the ground 51.

[0027] Next, when the rotor rotation angle is 30°, the control unit 60 performs switching to connect terminals 30b and 30l to the voltage source 50, and to connect terminal 30f, which has an electrical angle difference of 120° with respect to terminal 30b, and terminal 30h, which has an electrical angle difference of 120° with respect to terminal 30l, to ground 51, and not to connect the other terminals to the voltage source 50 or ground 51. Next, when the rotor rotation angle is 60°, the control unit 60 performs switching to connect terminals 30c and 30a to the voltage source 50, and to connect terminal 30g, which has an electrical angle difference of 120° with respect to terminal 30c, and terminal 30i, which has an electrical angle difference of 120° with respect to terminal 30a, to ground 51, and not to connect the other terminals to the voltage source 50 or ground 51.

[0028] Thereafter, when the rotor rotation angle changes in the order of 90°, 120°, 150°, 210°, 240°, 270°, 300°, and 330°, the control unit 60 sequentially connects the terminals 30d and 30b, 30e and 30c, 30f and 30d, 30g and 30e, 30h and 30f, 30i and 30g, 30j and 30h, 30k and 30i, and 30l and 30j to the voltage source 50. , terminals 30h and 30j, 30i and 30k, 30j and 30l, 30k and 30a, 30l and 30b, 30a and 30c, 30b and 30d, 30c and 30e, and 30d and 30f, which are positioned at an electrical angle of 120° from these terminals, are successively connected to ground 51, and the other terminals are successively switched so as not to be connected to voltage source 50 or ground 51. This allows polyphase motor 10 to operate in the medium speed range.

[0029] In this manner, when the polyphase motor 10 is driven in the medium speed range, the control unit 60 performs switching so that a terminal located at an electrical angle difference of 120° with respect to one terminal connected to the voltage source 50 is connected to ground 51. The control unit 60 also performs switching so that a terminal located at an electrical angle difference of 180° with respect to one terminal connected to the voltage source 50 is connected to ground 51. The control unit 60 also performs switching so that a terminal located at an electrical angle difference of 120° with respect to one terminal connected to the voltage source 50 is connected to the voltage source 50. In other words, the control unit 60 performs switching so that the electrical angle difference between the terminal connected to the voltage source 50 and the terminal connected to ground 51 is 120° with respect to the terminal connected to the voltage source 50, and there are two pairs of terminals, one connected to the voltage source 50 and one connected to ground 51. Note that the total number of energized coils in the stator coil 20 of the polyphase motor 10 at this time is eight.

[0030] Next, with reference to Table 3, switching of the voltage switch unit 41 and the ground switch unit 42 connected to each of the terminals 30a to 30l when the polyphase motor 10 is driven in a high speed range higher than the medium speed range will be described.

[0031] [Table 3]

[0032] Table 3 shows the switching states of the energized phases of terminals 30a-30l when polyphase motor 1 is driven in the high-speed range. When the rotation angle of the rotor (not shown) is 0°, control unit 60 turns on voltage switch unit 41 connected to terminal 30a and turns off ground switch unit 42, connecting terminal 30a to voltage source 50. Control unit 60 also turns off voltage switch unit 41 connected to terminal 30d, which is at an electrical angle difference of 90° from terminal 30a, and turns on ground switch unit 42, connecting terminal 30d to ground 51. Control unit 60 also turns off voltage switch unit 41 connected to terminal 30g, which is at an electrical angle difference of 180° from terminal 30a, and turns on ground switch unit 42, connecting terminal 30g to ground 51. Furthermore, the control unit 60 turns on the voltage switch unit 41 connected to the terminal 30j that is at an electrical angle difference of 90° with respect to the terminal 30g, and turns off the ground switch unit 42, thereby connecting the terminal 30j to the voltage source 50. Furthermore, the control unit 60 turns off the voltage switch unit 41 and the ground switch unit 42 connected to the terminals 30b, 30c, 30e, 30f, 30h, 30i, 30k, and 30l other than the terminals 30a, 30d, 30g, and 30j, thereby disconnecting the terminals 30b, 30c, 30e, 30f, 30h, 30i, 30k, and 30l from the voltage source 50 and the ground 51.

[0033] Next, when the rotor rotation angle is 30°, the control unit 60 performs switching to connect terminals 30b and 30k to the voltage source 50, and to connect terminal 30e, which has an electrical angle difference of 90° with respect to terminal 30b, and terminal 30h, which has an electrical angle difference of 90° with respect to terminal 30k, to ground 51, and not to connect the other terminals to the voltage source 50 or ground 51. Next, when the rotor rotation angle is 60°, the control unit 60 performs switching to connect terminals 30c and 30l to the voltage source 50, and to connect terminal 30f, which has an electrical angle difference of 90° with respect to terminal 30c, and terminal 30i, which has an electrical angle difference of 90° with respect to terminal 30l, to ground 51, and not to connect the other terminals to the voltage source 50 or ground 51.

[0034] Thereafter, when the rotor rotation angle changes sequentially to 90°, 120°, 150°, 210°, 240°, 270°, 300°, and 330°, the control unit 60 sequentially connects terminals 30d and 30a, 30e and 30b, 30f and 30c, 30g and 30d, 30h and 30e, 30i and 30f, 30j and 30g, 30k and 30h, and 30l and 30i to the voltage source 50, sequentially connects terminals 30g and 30j, 30h and 30k, 30i and 30l, 30j and 30a, 30k and 30b, 30l and 30c, 30a and 30d, 30b and 30e, and 30c and 30f to the ground 51, and sequentially switches the other terminals so that they are not connected to the voltage source 50 or the ground 51. This allows the polyphase motor 10 to be driven in the high speed range.

[0035] In this manner, when the polyphase motor 10 is driven in the high-speed range, the control unit 60 performs switching so that a terminal located at an electrical angle difference of 90° with respect to one terminal connected to the voltage source 50 is connected to the ground 51. The control unit 60 also performs switching so that a terminal located at an electrical angle difference of 180° with respect to one terminal connected to the voltage source 50 is connected to the ground 51. The control unit 60 also performs switching so that a terminal located at an electrical angle difference of 90° with respect to one terminal connected to the voltage source 50 is connected to the voltage source 50. In other words, the control unit 60 performs switching so that the electrical angle difference between the terminal connected to the voltage source 50 and the terminal connected to the ground 51 is 90° with respect to the terminal connected to the voltage source 50, and so that there are two pairs of terminals, one connected to the voltage source 50 and one connected to the ground 51. Note that the total number of energized coils in the stator coil 20 of the polyphase motor 10 at this time is six.

[0036] As described above, in the polyphase motor drive device 1, the control unit 60 switches the voltage switch unit 41 and the ground switch unit 42 so that when the polyphase motor 10 is driven in the low-speed range, the number of current-carrying coils in the stator coil 20 is 12 in total, when the polyphase motor 10 is driven in the medium-speed range, the number of current-carrying coils in the stator coil 20 is 8 in total, and when the polyphase motor 10 is driven in the high-speed range, the number of current-carrying coils in the stator coil 20 is 6 in total. As a result, as the drive speed of the polyphase motor 1, i.e., the number of rotations, increases, the number of current-carrying coils in the stator coil 20 decreases, and the back electromotive force generated in the stator coil 20 due to the increase in rotation speed is reduced, making it possible to drive the polyphase motor 1 in the high-speed range. Furthermore, in the multi-phase motor 10 of this embodiment, when driven at high speeds, there is no need to flow current for field-weakening control in order to reduce back electromotive force, so the current consumption of the multi-phase motor is reduced compared to conventional multi-phase motor drive devices, and the torque generation efficiency of the motor relative to the current flowing through the multi-phase motor 10 is improved.

[0037] As described above, the polyphase motor drive device 1 according to this embodiment includes a polyphase motor 10 having five or more phases, the polyphase motor 10 having stator coils 20 and terminal portions 30 provided at both ends of each stator coil 20, each terminal portion 30 of each stator coil 20 being connected to each terminal portion 30 of each stator coil 20 of an adjacent phase, a voltage switch portion 41 connected between each terminal portion 30 of each stator coil 20 and a voltage source 50, a ground switch portion 42 connected between each terminal portion of each stator coil 20 and ground 51, and a control portion 60 that controls opening and closing of the voltage switch portion 41 and the ground switch portion 42, and when the rotation speed of the polyphase motor 10 is a first speed, the control portion 60 turns on the voltage switch portion 41 connected to at least one first terminal portion 30 and turns off the ground switch portion 42, and turns on the voltage switch portion 41 connected to at least one second terminal portion positioned at a first electrical angle difference from at least one first terminal portion 30. When the rotation speed of the polyphase motor 1 is a second speed that is faster than the first speed, the voltage switch unit 41 connected to at least one first terminal unit 30 is turned on and the ground switch unit 42 is turned off, the voltage switch unit 41 connected to at least one third terminal unit 30 that is positioned at a second electrical angle difference that is smaller than the first electrical angle difference with respect to the at least one first terminal unit 30 is turned off and the ground switch unit 42 is turned on, and the voltage switch unit 41 and the ground switch unit 42 of each terminal unit 30 connected to other than the at least one first terminal unit 30 and the at least one third terminal unit 30 are turned off. Therefore, when the polyphase motor is driven in a high-speed range, the torque generation efficiency of the motor with respect to the current flowing through the motor can be improved.

[0038] Furthermore, a method for controlling a polyphase motor according to the present embodiment includes a polyphase motor (10) having five or more phases, the polyphase motor (10) having stator coils (20) and terminal portions (30) provided at both ends of each stator coil (20), the terminal portions (30) of each stator coil (20) being connected to the terminal portions (30) of the stator coils (20) of adjacent phases, the terminal portions (30) of each stator coil (20) being connected to the terminal portions (30) of the stator coils (20) being connected to the terminal portions (30) of the stator coils (20) of adjacent phases, the polyphase motor drive device (1) having a voltage switch portion (41) connected between each terminal portion (30) of each motor coil and a voltage source (50), a ground switch portion (42) connected between each terminal portion of each motor coil and ground (51), and a control portion (60) that controls opening and closing of the voltage switch portion (41) and the ground switch portion (42), the control portion (60) controlling the control portion (60) when the rotation speed of the polyphase motor (10) is a first speed, the control portion (60) turning on the voltage switch portion (41) connected to at least one first terminal portion (30) and turning off the ground switch portion (42), and turning off the voltage switch portion (41) connected to at least one second terminal portion (30) positioned at a first electrical angle difference with respect to the at least one first terminal portion (30) and turning off the ground switch portion (42). and turning off the voltage switch unit 41 and the ground switch unit 42 connected to each terminal unit 30 other than the at least one first terminal unit 30 and the at least one second terminal unit 30; and a second step in which, when the rotation speed of the polyphase motor is a second speed higher than the first speed, the control unit 60 controls the voltage switch unit 41 connected to the at least one first terminal unit 30 to be turned on and the ground switch unit 42 to be turned off, the voltage switch unit 41 connected to at least one third terminal unit 30 that is positioned at a second electrical angle difference with respect to the at least one first terminal unit 30 that is smaller than the first electrical angle difference, to be turned off and the ground switch unit 42 to be turned on, and the voltage switch unit 41 and the ground switch unit 42 connected to each terminal unit 30 other than the at least one first terminal unit 30 and the at least one third terminal unit 30 to be turned off. Therefore, when the polyphase motor is driven at a high speed, the torque generation efficiency of the motor with respect to the current flowing through the motor can be improved.

[0039] In this embodiment, the voltage switch unit 41 and the ground switch unit 42 are configured by MOSFETs, but this is not limited to this and they may be configured by other types of switching elements, such as IGBTs or bipolar transistors.

[0040] Furthermore, in this embodiment, the polyphase motor 10 is a DC brushless motor, and is a polyphase motor with 12 phases per two poles, but is not limited to this, and may be a motor with other numbers of poles and phases as long as it has five or more phases per two poles, or may be a motor of other types.

[0041] Furthermore, in this embodiment, when driving the polyphase motor 10, drive power is supplied to each stator coil 20 by PWM control, but drive power may also be supplied to each stator coil 20 by control other than PWM control. [Industrial Applicability]

[0042] The polyphase motor drive device 1 according to this embodiment includes a polyphase motor 10 having five or more phases, the polyphase motor 10 having stator coils 20 and terminal portions 30 provided at both ends of each stator coil 20, each terminal portion 30 of each stator coil 20 being connected to each terminal portion 30 of each stator coil 20 of an adjacent phase, a voltage switch portion 41 connected between each terminal portion 30 of each stator coil 20 and a voltage source 50, a ground switch portion 42 connected between each terminal portion of each stator coil 20 and ground 51, and a control portion 60 that controls opening and closing of the voltage switch portion 41 and the ground switch portion 42, and when the rotation speed of the polyphase motor 10 is a first speed, the control portion 60 turns on the voltage switch portion 41 connected to at least one first terminal portion 30 and turns off the ground switch portion 42, turns off the voltage switch portion 41 connected to at least one second terminal portion located at a first electrical angle difference with respect to the at least one first terminal portion 30 and turns on the ground switch portion 42, When the rotation speed of the polyphase motor 1 is a second speed that is faster than the first speed, the voltage switch unit 41 connected to at least one first terminal unit 30 is turned on and the ground switch unit 42 is turned off, when the rotation speed of the polyphase motor 1 is a second speed that is faster than the first speed, the voltage switch unit 41 connected to at least one first terminal unit 30 is turned off and the ground switch unit 42 is turned off, when the rotation speed of the polyphase motor 1 is a second speed that is faster than the first speed, the voltage switch unit 41 connected to at least one third terminal unit 30 that is positioned at a second electrical angle difference that is smaller than the first electrical angle difference with respect to the at least one first terminal unit 30 is turned off and the ground switch unit 42 is turned on, and the voltage switch unit 41 and the ground switch unit 42 of each terminal unit 30 connected to other than the at least one first terminal unit 30 and the at least one third terminal unit 30 are turned off. Therefore, when the polyphase motor is driven in a high-speed range, the torque generation efficiency of the motor with respect to the current flowing through the polyphase motor can be improved, and the polyphase motor drive device 1 is suitable for use in a polyphase motor drive device 1 for a polyphase motor 10 that is driven in a high-speed range. [Explanation of symbols]

[0043] 10 polyphase motor, 20 stator coil (motor coil), 30, 30a to 30l terminal section, 41 voltage switch section, 42 ground switch section, 50 voltage source, 51 ground, 60 control section.

Claims

1. A polyphase motor (10) having five or more phases, A motor coil (20); Terminal portions (30) provided on both ends of each of the motor coils (20); a polyphase motor (10) having Each terminal portion (30) of each motor coil (20) is connected to each terminal portion (30) of each motor coil (20) of an adjacent phase, a voltage switch section (41) connected between each terminal section (30) of each motor coil (20) and a voltage source (50); a ground switch section (42) connected between each terminal section of each motor coil (20) and a ground (51); a control unit (60) that controls opening and closing of the voltage switch unit (41) and the ground switch unit (42); Equipped with The control unit (60) When the rotation speed of the polyphase motor (1) is a first speed, the voltage switch unit (41) connected to at least one first terminal unit (30) is turned on and the ground switch unit (42) is turned off, the voltage switch unit (41) connected to at least one second terminal unit located at a first electrical angle difference with respect to the at least one first terminal unit (30) is turned off and the ground switch unit (42) is turned on, and the voltage switch unit (41) and the ground switch unit (42) connected to each of the terminal units (30) other than the at least one first terminal unit (30) and the at least one second terminal unit (30) are turned off, When the rotation speed of the polyphase motor (1) is a second speed that is higher than the first speed, the polyphase motor drive device performs control so that the voltage switch unit (41) connected to the at least one first terminal unit (30) is turned on and the ground switch unit (42) is turned off, the voltage switch unit (41) connected to at least one third terminal unit (30) that is located at a second electrical angle difference that is smaller than the first electrical angle difference with respect to the at least one first terminal unit (30) is turned off and the ground switch unit (42) is turned on, and the voltage switch unit (41) and the ground switch unit (42) connected to each of the terminal units (30) other than the at least one first terminal unit (30) and the at least one third terminal unit (30) are turned off.

2. A polyphase motor (10) having five or more phases, A motor coil (20); Terminal portions (30) provided on both ends of each of the motor coils (20); a polyphase motor (10) having Each terminal portion (30) of each motor coil (20) is connected to each terminal portion (30) of each motor coil (20) of an adjacent phase, a voltage switch section (41) connected between each terminal section (30) of each motor coil and a voltage source (50); a ground switch section (42) connected between each terminal section of each motor coil and a ground (51); a control unit (60) that controls opening and closing of the voltage switch unit (41) and the ground switch unit (42); In a polyphase motor drive device (1) having a first step in which the control unit (60) controls, when the rotation speed of the polyphase motor (10) is a first speed, to turn on the voltage switch unit (41) connected to at least one first terminal unit (30) and turn off the ground switch unit (42), turn off the voltage switch unit (41) connected to at least one second terminal unit (30) positioned at a first electrical angle difference from the at least one first terminal unit (30) and turn on the ground switch unit (42), and turn off the voltage switch unit (41) and the ground switch unit (42) connected to each of the terminal units (30) other than the at least one first terminal unit (30) and the at least one second terminal unit (30); and a second step of controlling, by the control unit (60), when the rotation speed of the polyphase motor (10) is a second speed higher than the first speed, to turn on the voltage switch unit (41) connected to the at least one first terminal unit (30) and turn off the ground switch unit (42), turn off the voltage switch unit (41) connected to at least one third terminal unit (30) located at a second electrical angle difference smaller than the first electrical angle difference with respect to the at least one first terminal unit (30) and turn on the ground switch unit (42), and turn off the voltage switch unit (41) and the ground switch unit (42) connected to each of the terminal units (30) other than the at least one first terminal unit (30) and the at least one third terminal unit (30).

Images