JP2015109733A - Motor unit - Google Patents

Abstract

PROBLEM TO BE SOLVED: To reduce a dead space, while suppressing an installation space as an entire unit, by sufficiently suppressing temperature rise of a capacitor.SOLUTION: A motor unit includes: a cylindrical motor exterior wall 1; a motor 2 provided on an inner peripheral side of the motor exterior wall 1; and a coolant circulation path 3 positioned between an outer peripheral surface 1a of the motor exterior wall 1 and the motor 2. On a part of the outer peripheral surface 1a of the motor exterior wall 1 positioned in an outer peripheral side direction of the coolant circulation path 3, a capacitor 5 is protrusively provided that forms a part of an inverter circuit 41 of a motor driving device 4. The capacitor 5 functions as one of various electric components forming the inverter circuit 41 and has desired electric capacity. A box-like capacitor that is protrusively provided so as to cover a part of the outer peripheral surface 1a of the motor exterior wall 1 positioned in the outer peripheral side direction of the coolant circulation path 3 is applied. The shape of the capacitor 5 closer to the motor exterior wall 1 extends along the outer peripheral surface 1a of the motor exterior wall 1 covered by the capacitor 5.

Description

  The present invention relates to a motor unit that includes a motor drive device having an inverter circuit and is driven by desired AC power output from the motor drive device.

  In a motor unit having a motor drive device having an inverter circuit and driven by a motor (motor having a rotor and a stator) by a desired AC power output from the motor drive device, the motor unit is simply reduced in size. Instead of reducing the installation space for the application target (for example, an electric vehicle), it is required to efficiently install the motor unit to reduce the dead space. For example, a general capacitor (for example, an electrolytic capacitor) applied to an inverter circuit is an electrical component that has a relatively high height and easily forms a dead space. In other words, it is considered to reduce the installation space by an integrated configuration.

  In the case of Patent Document 1, an integrated configuration is disclosed in which a dead space caused by a motor and a capacitor is reduced by using a configuration in which a cylindrical capacitor and a motor that can be installed in a hollow portion inside the capacitor are used together. However, since the capacitor extends over the entire circumference of the motor exterior wall and the inverter circuit is expanded, the installation space occupied by the entire unit may be increased. On the other hand, in Patent Document 2, a motor driving device projects from a part of the outer peripheral surface of the motor outer wall, and a plurality of columnar capacitors are arranged in parallel along the outer peripheral surface of the motor outer wall (each of the motor driving devices). Compared with Patent Document 1, the inverter circuit is integrated (on the part of the outer peripheral surface of the motor exterior wall). The integrated configuration is such that the central axes of the capacitors are parallel to each other and parallel to the motor shaft. The dead space can be reduced while reducing the installation space occupied by the entire unit.

  In addition, the capacitor generates heat according to the operation state of the inverter circuit, and the electrical characteristics of the capacitor may change when the temperature rises. Therefore, it is desirable to configure a motor unit that can suppress the temperature rise. . In the case of Patent Document 2, it is disclosed that an elastic sheet is interposed between a plurality of cylindrical capacitors and a motor exterior wall, and heat of each capacitor is radiated through the elastic sheet to suppress temperature rise. ing.

JP 2004-153875 A JP 2004-44555 A

  However, the contact (or proximity) area between the elastic sheet and the columnar capacitor is small, and the heat of the capacitor cannot be sufficiently dissipated, and there is a possibility that the temperature rise cannot be suppressed. For example, a configuration that suppresses the rise in temperature by applying a capacitor (such as a small capacitor) that generates a small amount of heat can be considered, but the number of capacitors required to drive the motor increases, and the installation space occupied by the entire unit May be increased.

  The present invention has been made in view of such technical problems, and provides a motor drive device that can sufficiently suppress a rise in the temperature of a capacitor and can reduce a dead space while suppressing an installation space as a whole unit. It is to provide.

  The electronic control device according to the present invention is a creation that can solve the above-described problems. One aspect of the electronic control device includes a cylindrical motor exterior wall, a rotor and a stator, and is provided on the inner peripheral side of the motor exterior wall. The stator extending in the axial direction of the motor exterior wall, and a refrigerant circulation path positioned between the outer peripheral surface of the motor exterior wall and the motor, the motor having an inverter circuit A motor unit driven by AC power output from a motor driving device, wherein the inverter circuit covers a part of an outer peripheral surface of a motor outer wall located in an outer peripheral side direction of the refrigerant circulation path And the shape of the capacitor on the motor exterior wall side is a shape extending along the outer peripheral surface of the motor exterior wall covered with the capacitor.

  The refrigerant circulation path may be cylindrical and provided coaxially with the motor exterior wall. The refrigerant circulation path may extend in a coil shape with the axis of the motor exterior wall as an axis. Furthermore, a sheet-like elastic material having thermal conductivity may be interposed between the outer peripheral surface of the motor exterior wall and the motor exterior wall side of the capacitor.

  As described above, according to the present invention, the temperature rise of the capacitor can be sufficiently suppressed, and the dead space can be reduced while suppressing the installation space of the entire unit.

BRIEF DESCRIPTION OF THE DRAWINGS Schematic explanatory drawing which shows an example of the motor unit in this embodiment ((A) is a cross-sectional view, (B) is a longitudinal cross-sectional view). The schematic circuit diagram which shows an example of the inverter circuit of the motor drive device applied to the motor unit of FIG.

  In the motor unit of the embodiment of the present invention, a refrigerant circulation path is provided between the outer peripheral surface of the motor outer wall and the motor, and a simple cylindrical capacitor is applied in the inverter circuit of the motor drive device. Instead, a box-like capacitor is used that projects so as to cover a part of the outer peripheral surface of the motor exterior wall located in the outer peripheral side direction of the refrigerant circulation path. The shape of the motor exterior wall side in the capacitor of this embodiment is a shape that extends along the outer peripheral surface of the motor exterior wall that is covered by the capacitor (hereinafter, the outer peripheral surface of the coated portion is the coated surface). ing.

  According to such a motor unit of the present embodiment, the inverter circuits are easily aggregated (eg, aggregated from Patent Document 1) on the covering surface side of the motor exterior wall, and the entire unit is reduced in size and the installation space is suppressed. It is possible to reduce the dead space.

  Further, the contact (or proximity) area between the motor exterior wall side of the capacitor and the covering surface of the motor exterior wall can be made larger than that of the conventional motor unit, and the heat exchange efficiency between the two can be improved. It will be. As a result, for example, the heat of the condenser that can generate heat according to the operating state of the inverter circuit is easily removed by the refrigerant circulation path located between the outer peripheral surface of the motor exterior wall and the motor, and the temperature rise in the condenser is sufficient. It is possible to suppress and exert desired electrical characteristics. If the electrical characteristics of the capacitor can be exhibited sufficiently in this way, it will lead to a reduction in the size of the capacitor (or reduction in the number when multiple capacitors are applied), and the motor unit will be further reduced in size and weight. There is a possibility that it can contribute to conversion.

  The motor unit according to the present embodiment only needs to be applied with the box-shaped capacitor as described above, and is generally known in various fields such as the motor field, the refrigerant circuit field, and the inverter circuit field. It is possible to make appropriate changes by applying the technology, and specific examples shown below are given as an example.

<Example of motor unit>
A motor unit 10 shown in FIG. 1 (A: schematic cross-sectional view) and (B: schematic vertical cross-sectional view) is an example of this embodiment, and mainly includes a cylindrical motor exterior wall 1 and a motor exterior wall. 1 is provided with a motor 2 provided on the inner peripheral side of the motor 1, and a refrigerant circulation path 3 positioned between the outer peripheral surface 1a of the motor exterior wall 1 and the motor 2, and is positioned in the outer peripheral side direction of the refrigerant circulation path 3. A capacitor 5 that constitutes a part of the inverter circuit 41 of the motor drive device 4 protrudes from a part of the outer peripheral surface 1 a of the motor exterior wall 1.

  The motor outer wall 1 may be of various forms as long as it can cover and accommodate the target motor 2, the refrigerant circulation path 3, etc. on the inner peripheral side of the outer peripheral surface 1 a of the motor outer wall 1. For example, a stainless steel plate or the like is formed into a cylindrical shape and applied with an exterior wall to which desired characteristics (mechanical strength, corrosion resistance, etc.) are imparted. As a specific example, there is a motor exterior wall 1 formed in an annular cross section as shown in FIG. 1 (A). However, as long as the target motor 2 can be accommodated as described above, The surface may be formed into a rectangular shape, an elliptical shape, or the like.

  The motor 2 has a rotor (for example, a rotor formed of a permanent magnet or the like and rotated by a rotating magnetic field) 2a and a stator (for example, a stator coil) 2b and is disposed on the inner peripheral side of the motor exterior wall 1. As long as the rotor 2a is rotationally driven by the AC power output from the inverter circuit 41 of the motor driving device 4, various forms can be applied. For example, an electric vehicle, an elevator, etc. The thing of the form applied in various fields is mentioned. As a specific example, as shown in FIG. 1, a cylindrical rotor 2a made of a permanent magnet or the like and rotatably supported (for example, supported via a bearing or the like outside the figure), and a rotation A fixed output which is formed by using a rotation output shaft 2c protruding in the axial direction of the rotor 2a on one end side of the rotor 2a, a stator coil, etc., and covering the outer peripheral side of the rotor 2a. And a motor 2 having a child 2b.

  The refrigerant circulation path 3 is a circulation path provided between the outer peripheral surface 1a of the motor exterior wall 1 and the motor 2 so as not to obstruct the driving of the motor 2, and a refrigerant such as cooling water circulates to cause the motor 2 to circulate. As long as it can cool (heat from the motor 2 is removed), various forms can be applied. For example, a water-cooled jacket applied to a general water-cooled motor unit (For example, the water cooling jacket 20 of Unexamined-Japanese-Patent No. 8-298750 is mentioned.) As a specific example, as shown in FIG. 1, a cylindrical refrigerant circulation path 3 provided coaxially with the motor exterior wall 1 on the inner peripheral side of the motor exterior wall 1 can be mentioned. In addition, for example, a long linear circulation path is formed, and between the outer peripheral surface 1a of the motor exterior wall 1 and the motor 2, the motor exterior wall 1 is directed from one end side to the other end side direction. The thing of the form extended spirally toward is mentioned. Further, the refrigerant circulation path 3 may be formed separately from the motor exterior wall 1 and formed integrally with the motor exterior wall 1 (for example, between the outer peripheral surface 1a and the inner peripheral surface 1b of the motor exterior wall 1). It may be formed integrally so as to be buried in between. The means for circulating the refrigerant in the refrigerant circulation path 3 is not particularly limited. For example, as shown in FIG. 1, a refrigerant introduction port 3a and a refrigerant discharge port 3b are formed in the refrigerant circulation path 3, and a pump not shown in the figure. The method of circulating a refrigerant | coolant to the refrigerant circuit 3 through the above etc. is mentioned. The size of the refrigerant circulation path 3, the amount of refrigerant circulation, and the like may be set as appropriate so that the motor 2 and the condenser 5 and the like for cooling can be sufficiently cooled.

  The motor driving device 4 includes an inverter circuit 41 that is connected to various electrical components including the capacitor 5 and can output desired AC power to the motor 2 via the inverter circuit 41. Various forms can be applied. For example, an inverter circuit 41 as shown in FIG. 2 can be installed on the outer peripheral side of the motor exterior wall 1. In the case of the inverter circuit 41 in FIG. 2, the inverter circuit 41 is disposed between the input power source 42 and the motor 2, and is mainly a three-phase circuit composed of a plurality of (six in FIG. 2) switching elements 43a and the like. A forward converter 43 having a configuration in which the AC input side of the bridge circuit 43b is connected to the output side of the input power supply 42, a capacitor 5 connected in parallel to the DC output side of the forward converter 43, and a plurality of capacitors (in FIG. And a reverse conversion unit 44 in which the DC side of the three-phase bridge circuit 44b composed of six switching elements 44a and the like is connected to the output side of the capacitor 5 and the AC output side of the three-phase bridge circuit 44b is connected to the motor 2. Has been. Further, a filter reactor 45 and a filter capacitor 46 are connected between the input power source 42 and the forward conversion unit 43 and between the reverse conversion unit 44 and the motor 2, respectively.

  The capacitor 5 functions as one of various electric components constituting the inverter circuit 41 as shown in FIG. 2 and has a desired electric capacity. As shown in FIG. As long as it is a box-like thing projecting so as to cover a part (coating surface) of the outer peripheral surface 1a of the motor exterior wall 1 located in the outer peripheral side direction, various forms can be applied. For example, a conductor having a desired electric capacity in which a gap or a dielectric (for example, mica) is interposed between two conductors arranged to face each other. In the case of the capacitor 5 shown in FIG. 1, the capacitor 5 is formed in a box shape, and the shape on the motor exterior wall 1 side is along the coated surface covered by the capacitor 5 on the outer peripheral surface 1 a of the motor exterior wall 1. It has an extended shape, that is, a shape extending along the circumferential direction of the outer peripheral surface 1a of the motor exterior wall 1 (for example, a shape having a circular arc shape as shown in FIG. 1A). As a method for forming such a capacitor 5, for example, a box-shaped capacitor body 5 b is formed by bundling a laminated structure film in which sheet-like mica is interposed between two sheet-like conductors in, for example, a twisted shape or a roll shape. A method of covering the capacitor main body 5b with a box-shaped capacitor protective wall 5a can be mentioned. As the capacitor protection wall 5a, for example, a thin-walled box-shaped protection wall formed by molding a material such as an insulating or thermal conductive resin may be used, but it is not particularly limited.

  For example, a sheet-like elastic material (not shown) having thermal conductivity may be interposed between the motor exterior wall 1 and the capacitor 5. By interposing the sheet-like elastic material in this way, adhesion, vibration resistance, and impact resistance (for example, driving of the motor 2 etc.) are ensured while ensuring sufficient heat exchange efficiency between the motor exterior wall 1 and the capacitor 5. There is a possibility that it can contribute to an improvement in durability against vibrations and shocks caused by it.

  Although the present invention has been described in detail only for the specific examples described above, it is obvious to those skilled in the art that various modifications can be made within the scope of the technical idea of the present invention. It is natural that such changes and the like belong to the scope of the claims.

  For example, in this embodiment, the structure in which the capacitor 5 of the inverter circuit 41 protrudes from the motor exterior wall 1 has been specifically described. However, in another electrical component (for example, the filter capacitor 46 of the inverter circuit 41) related to the motor unit. Also, the temperature rise of the other electrical components can be sufficiently suppressed by designing the same as the capacitor 5 (for example, a box shape like the capacitor 5 shown in FIG. 1) and projecting it on the motor exterior wall 1. Or reducing the dead space while reducing the installation space of the entire unit.

DESCRIPTION OF SYMBOLS 1 ... Motor exterior wall 10 ... Motor unit 2 ... Motor 2a ... Rotor 2b ... Stator 2c ... Rotation output shaft 3 ... Refrigerant circuit 4 ... Motor drive device 41 ... Inverter circuit 5 ... Capacitor

Claims (4)

A cylindrical motor exterior wall, a motor having a rotor and a stator, provided on the inner peripheral side of the motor exterior wall, the stator extending in the axial direction of the motor exterior wall, and an outer periphery of the motor exterior wall A refrigerant circulation path located between the surface and the motor,
The motor is a motor unit that is driven by AC power output from a motor driving device having an inverter circuit,
The inverter circuit has a box-shaped capacitor that covers a part of the outer peripheral surface of the motor exterior wall located in the outer peripheral side direction of the refrigerant circuit,
The motor unit characterized in that the shape of the capacitor on the side of the motor outer wall extends along the outer peripheral surface of the motor outer wall covered by the capacitor.   The motor unit according to claim 1, wherein the refrigerant circulation path is cylindrical and provided coaxially with the motor exterior wall.   3. The motor unit according to claim 1, wherein the refrigerant circulation path extends in a coil shape about the axis of the motor exterior wall. 4.   The motor unit according to any one of claims 1 to 3, wherein a sheet-like elastic material having thermal conductivity is interposed between the outer peripheral surface of the motor exterior wall and the motor exterior wall side of the capacitor.

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