JP4039288B2 - Power converter - Google Patents

Description

[0001]
BACKGROUND OF THE INVENTION
The present invention relates to a driving power for driving an AC motor, and relates to a power converter that converts DC power into AC power.
[0002]
[Prior art]
[Patent Literature]
Japanese Patent Laid-Open No. 5-292703.
[0003]
In the above-mentioned patent document, a cooler that cools both the motor and the power conversion device is disposed between the motor and the power conversion device, and the motor and the power conversion device are integrally formed by the cooler. The power semiconductor module is forcibly cooled.
[0004]
[Problems to be solved by the invention]
In the above prior art, when the required power amount of the motor is large, the size of the power semiconductor module that converts DC power into AC power increases, and the cooler also increases accordingly. Further, the radial cross-sectional area required by the power converter increases, and there is a problem that the motor and the power converter are integrated more than necessary.
[0005]
The present invention has been made to solve the above-described problems, and an object of the present invention is to provide a power conversion device that is small and excellent in cooling performance even when the required power amount of the motor is large.
[0006]
[Means for Solving the Problems]
According to claim 1 of the present invention , at least one cylindrical flat or polygonal flat cooler centering on the motor shaft or drive shaft is provided, and the cooling surface of the cooler is perpendicular to the motor shaft or drive shaft. to, on both surfaces of the cooling surface of the cooler, equipped with a power semiconductor module for supplying power to the motor, and the terminal arrangement of the power semiconductor module between both surfaces of the cooling surfaces, to each other across the cooler It is configured to have a symmetric relationship.
According to a sixth aspect of the present invention, at least one cylindrical flat or polygonal flat cooler centered on the motor shaft or drive shaft is provided, and a cooling surface of the cooler is provided on the motor shaft or drive shaft. A power semiconductor module that supplies power to the motor is mounted on one or both sides of the cooling surface of the cooler at a right angle to the shaft, and the power semiconductor module mounted on the cooler is one of the cooling devices. One AC phase is arranged radially on the surface or on one of the coolers with the motor shaft or the drive shaft as the center .
[0007]
【The invention's effect】
According to the present invention, at least one cylindrical flat or polygonal flat cooler centered on the motor shaft or drive shaft is provided, and power is supplied to the motor on one or both surfaces of the cooling surface of the cooler. By mounting the power semiconductor module, the power converter can be downsized.
[0008]
DETAILED DESCRIPTION OF THE INVENTION
Hereinafter, embodiments of the present invention will be described with reference to the drawings. In the drawings described below, components having the same function are denoted by the same reference numerals, and repeated description thereof is omitted.
[0009]
FIG. 1 is an external configuration diagram of an integrated device of a power converter 1 and an electric vehicle motor 2 according to the present invention. The vehicle on which the integrated device of the power conversion device 1 and the motor 2 shown in FIG. 1 is mounted is not limited to a vehicle on which only the motor 2 is mounted as a drive source. The power converter 1 and the motor 2 are characterized by an integrated device. The power converter 1 is arranged in series with the motor 2 along the axis of the motor 2 and integrated with the drive shaft 4 at the center. It is to penetrate. A portion where the drive shaft 4 penetrates the center of the power conversion device 1 is covered with a cylindrical structural member 101 surrounding the drive shaft 4, and the cylindrical structural member 101 is connected to the structural member 102 on the end surface of the motor 2. It is integrated. The motor 2 is driven by the AC power of the power converter 1, and the mechanical output of the motor 2 is transmitted to the wheels via a gear 3 integrated with the motor 2 in the opposite direction to the power converter 1 and a drive shaft 4. The vehicle is driven. Here, the motor shaft and the drive shaft are formed on the same axis, and it is apparent that the present invention can be applied even when the motor shaft passes through the power conversion device 1.
[0010]
FIG. 2 is a schematic power system diagram of an electric vehicle drive system using the power conversion device 1 of the present invention. In FIG. 2, the power conversion device 1 converts the DC power supplied from the battery 5 through the power supply line 6 into AC power by the switching operation of the built-in power semiconductor modules 71 to 73 and supplies the motor 2 as drive power. Supply. As shown in FIG. 2, when the motor 2 is an AC motor having three phases of an AC U phase, a V phase, and a W phase, the power conversion device 1 includes a total of three power semiconductor modules 71 to 73, and the power semiconductor AC U-phase, V-phase, and W-phase power is extracted from each output terminal of modules 71 to 73 and input to each phase of motor 2 via current sensors 91 to 93. A DC voltage from the battery 5 is applied to each of the power semiconductor modules 71 to 73 through the feeder line 6. Further, smoothing capacitors 81 to 86 are connected to the power supply line 6 in parallel with the power semiconductor modules 71 to 73. The smoothing capacitors 81 to 86 are capacitors for smoothing the voltage from the battery 5, and since a large capacity is required, usually a plurality of capacitors are connected in parallel. The power semiconductor modules 71 to 73 are configured by a pair of power semiconductor elements such as IGBTs (Insulated Gate Bipolar Transistors), and the connection point of the pair is an AC output terminal. A diode is connected in antiparallel to each power semiconductor element. In FIG. 2, one power semiconductor module is connected for one AC phase. However, when it is necessary to supply high power to the motor 2, a plurality of power semiconductor modules are connected in parallel for one AC phase. . In FIG. 2, the control-related system for controlling the switching of the power semiconductor modules 71 to 73 and converting DC power to AC power is omitted, but three-phase is used for control to convert DC power to AC power. Since it is necessary to measure the current flowing in the alternating current (U phase, V phase, W phase), the current sensors 91 to 93 are arranged in the power converter 1.
[0011]
Next, a first embodiment of the present invention will be described with reference to FIGS. FIG. 3 is a side view showing the internal configuration of the power conversion apparatus 1 showing the first embodiment of the present invention. FIG. 3 illustrates the motor 2 as viewed from the side opposite to the side where the power converter 1 is mounted. The configuration of the present invention is shown using FIG.
[0012]
A cylindrical flat cooler 11 (the cooler 11 may be a polygonal flat shape having a circular center part and a polygonal outer peripheral part) for mounting the power semiconductor modules 71A, 72A, 73A on both sides. A plurality of cooling liquid passages 46 (FIG. 5) having a flat portion and through which the cooling liquid flows are provided, and there are cooling liquid piping paths 111 and 112 through which the cooling liquid enters and exits the plurality of cooling liquid passages 46. . The power semiconductor modules 71A, 72A, 73A have a positive power supply terminal 70p, a negative power supply terminal 70n, and an AC output terminal 70a (FIG. 6) as input / output terminals on the side surfaces, and are arranged in the outer peripheral direction. When using four power semiconductor modules (FIG. 7, for example, 71A to 71D in U phase) connected in parallel to output one phase of AC output as in the first embodiment of the present invention, They are connected by AC output electrodes 21 to 23 (bus bars) that connect the output terminals 70a of the four power semiconductor modules. The AC output from the AC output electrodes 21 to 23 is obtained by converting the AC output from the power conversion device 1 to a motor via current sensors 91 to 93 that detect output currents of the three-phase AC U phase, V phase, and W phase. 2 is supplied to the motor 2 from AC output terminals 31 to 33 supplied to the motor 2. Large DC capacitors 81 to 86 for smoothing the DC voltage from the battery 5 are arranged at the DC input. At the center of the cooler 11, there is a structural member 101 surrounding the drive shaft 4 on which the cooler 11 is mounted. When the motor shaft passes through the power converter, the structural member surrounding the drive shaft may be a structural member surrounding the motor shaft.
[0013]
Next, the connection of the component parts of the first embodiment will be described. Here, in order to facilitate the explanation of the cooler 11, FIG. 4 is a perspective view showing only the configuration of the cooler 11 portion. There is another cooler 12 below the cooler 11 (on the motor side). In the coolers 11 and 12, the cooling surface 50 and the coolant passage 46 are arranged at right angles to the drive shaft 4 (parallel to the motor end surface 102). The central portions of the coolers 11 and 12 are attached to the structural member 101 surrounding the drive shaft 4. The coolers 11 and 12 are connected to coolant pipe lines 111 and 112 that enter and exit the power converter 1 and a pipe line 113 that connects the coolers 11 and 12. As shown in FIG. 5, a plurality of circular coolant passages 46 around the drive shaft 4 are formed in the coolers 11 and 12 in the radial direction of the drive shaft 4.
[0014]
The power semiconductor modules 71A, 72A, 73A are mounted on one cooling surface 50 of the cooler 11 in a radial manner centered on the drive shaft 4 at intervals of 120 °, and input / output terminals (positive power supply terminal 70p, negative power supply) The terminals 70n and the AC output terminals 70a) are arranged in the outer peripheral direction. Although not shown in the side view of FIG. 3 hidden behind the cooler 11, each of the three cooling surfaces 50 on the opposite side of the cooler 11 and both surfaces of the cooling surface 50 of the cooler 12 are similarly provided. The power semiconductor modules 71B, 72B, 73B, 71C, 72C, 73C, and 71D, 72D, 73D are mounted radially around the drive shaft 4 at intervals of 120 ° so that the input / output terminals on the side faces in the outer peripheral direction. To place. At this time, each of the four power semiconductor modules 71A to 71D, 72A to 72D, 73A to 73D is disposed on the same position in the circumferential direction around the drive shaft 4, and each of the coolers 11 and 12 is arranged. As shown in FIG. 6, the power semiconductor modules 71A and 71B, 72A and 72B, 73A and 73B, 71C and 71D, 72C and 72D, and 73C and 73D mounted on both surfaces of the cooling surface 50 are connected to each other as shown in FIG. A power semiconductor module having a symmetrical relationship with the cooler 11 in between is used and mounted. AC output electrodes (bus bars) 21 to 23 are connected to the AC output terminals 70p of the power semiconductor modules 71A to 71D, 72A to 72D, and 73A to 73D, respectively, and AC power is supplied to the motor 2 via the current sensors 91 to 93. Are connected to AC output terminals 31-33. The current sensors 91 to 93 and the AC output terminals 31 to 33 are arranged in the outer peripheral direction from the coolers 11 and 12, and the AC output from the AC output terminals 31 to 33 uses electrodes (bus bars). Then, the structural member 102 on the end face of the motor 2 is passed through and connected to the winding of the motor 2. FIG. 7 shows a schematic power system diagram for the U phase of the AC three-phase power in the configuration of FIG. As shown in FIG. 7, four power semiconductor modules 71A to 71D are connected in parallel, and the AC output terminal 70a of each power semiconductor module 71A to 71D is connected by the AC output electrode 21, and this U-phase AC output is a current. It is supplied from the AC output terminal 31 to the U-phase winding of the motor 2 via the sensor 91.
[0015]
The smoothing capacitors 81 to 86 are also arranged in the outer peripheral direction from the coolers 11 and 12, and two smoothing capacitors are arranged so as to sandwich the current sensors 91 to 93 and the AC output terminals 31 to 33 for each AC phase. . Although not shown here, the positive and negative electrodes (bus bars) to which the DC voltage from the battery 5 is applied via the feeder line 6 are not provided except for the portions connected to the respective components of the power converter 1. Are disposed so as to have the shortest distance between the components.
[0016]
In addition, since the power semiconductor modules 71A to 71D, 72A to 72D, and 73A to 73D are arranged radially with the drive shaft 4 as the center at intervals of 120 °, the smoothing capacitors 81 to 86 and the current sensors 91 to 93 and the AC output The components including the terminals 31 to 33 can be arranged in an equal positional relationship between the three phases, and the surge voltage and heat generation can be all made uniform.
[0017]
Moreover, since the center part of the coolers 11 and 12 is attached to the structural member 101 surrounding the drive shaft, the strength (rigidity) of the power conversion device 1 can be ensured. Further, a plurality of coolant passages 46 through which the coolant flows inside the coolers 11 and 12 are formed in a circular shape around the drive shaft 4 in the radial direction of the drive shaft 4. There is an effect that the entire surface of the power semiconductor modules 71A to 71D, 72A to 72D, and 73A to 73D to be mounted on can be cooled uniformly.
[0018]
In addition, the power semiconductor module for AC three phases is mounted on one cooling surface of the cooler, the power semiconductor module is mounted on both surfaces of the cooler, and the number of mounted cooler power converters 1 is changed. Since the structure is made possible, the surface on which the power semiconductor module is mounted on the cooler can be changed to one side or both sides depending on the required power of the motor, or the number of the cooler mounted on the power converter 1 can be changed. There is an effect that the power conversion device 1 can be optimized and downsized.
[0019]
Further, the power semiconductor modules 71A and 71B, 72A and 72B, 73A and 73B, 71C and 71D, 72C and 72D, and 72C and 73D mounted on both sides of one cooler have input / output terminals sandwiching the cooler. Since the power semiconductor modules that are symmetrical to each other are used and mounted, the connection of the AC output electrodes (bus bars) 21 to 23 and the positive and negative electrodes (bus bars) of DC power can be minimized and facilitated.
[0020]
Next, as a second embodiment of the present invention, a case where a plurality of power semiconductor modules 71A to 71C for one phase of alternating current are mounted on one cooling surface 50 of the cooler 11 will be described. It demonstrates using FIG. 8 which is a side view of the internal structure of the power converter device 1 which shows a form. The power semiconductor modules 71A to 71C mounted on the cooling surface 50 of the cooler 11 are largely different from FIG. 3 in that three power semiconductor modules 71A to 71C that output the U phase among the three AC phases, Three power semiconductor modules 71A to 71C are connected in parallel. The AC output terminals 70a of the power semiconductor modules 71A to 71C protrude from the positive power supply terminal 70p and the negative electrode terminal 70n in the outer peripheral direction, and the AC output terminal 70a is connected to the annular AC output electrode (bus bar) 21. That is. An AC output terminal 31 is connected to the annular AC output electrode (bus bar) 21 via a current sensor 91, and the AC output from the AC output terminal 31 is a structural member on the end face of the motor 2 using the electrode (bus bar). It is the same as FIG. 3 that passes through 102 and is connected to the winding of the motor 2. Other AC output V-phase and W-phase power semiconductor modules 72A to 72C, 73A to 73C and annular AC output electrodes (busbars) 22 and 23 are not shown because they are not visible, but each annular AC The V-phase and W-phase outputs connected to the output electrodes (bus bars) 22 and 23 are connected to the AC output terminals 32 and 33 via the current sensors 92 and 93 shown in the figure, and from the AC output terminals 32 and 33. The electrode penetrates the structural member 102 on the end surface of the motor 2 and is connected to the winding of the motor 2 as in the first embodiment. However, in the second embodiment, six power semiconductor modules 71A to 71C and 72A to 72C for U-phase and V-phase are mounted on both surfaces of the cooler 11, but the cooler 12 is cooled on one side. Only the three power semiconductor modules 73A to 73C for the W phase are mounted on the surface, and the power semiconductor module is not mounted on the other cooling surface.
[0021]
Here, an embodiment has been shown in which three power semiconductor modules are mounted on one side of a cooler when three power semiconductor modules are connected in parallel to one phase of AC, but four power semiconductor modules are mounted on one phase of an AC. When used in parallel, two power semiconductor modules can be mounted on one side of the cooler, and one cooler can be assigned to one AC phase.
[0022]
Also in this case, since the power semiconductor modules 71A to 71C, 72A to 72C, and 73A to 73C are arranged radially around the drive shaft 4 at intervals of 120 °, the smoothing capacitors 81 to 86 and the current sensors 91 to 93 The components including the AC output terminals 31 to 33 can be arranged in an equal positional relationship between the three phases, and the surge voltage and heat generation can be all made uniform.
[0023]
Moreover, since the center part of the coolers 11 and 12 is attached to the structural member 101 surrounding the drive shaft, the strength (rigidity) of the power conversion device 1 can be ensured. Further, a plurality of coolant passages 46 through which the coolant flows inside the coolers 11 and 12 are formed in a circular shape around the drive shaft 4 in the radial direction of the drive shaft 4. There is an effect that the entire surface of the power semiconductor modules 71A to 71C, 72A to 72C, and 73A to 73C mounted on can be uniformly cooled.
[0024]
Moreover, the power semiconductor module for one phase of alternating current is mounted on one cooling surface of the cooler, the power semiconductor module is mounted on both surfaces of the cooler, and the number of mounted cooler power converters 1 is changed. Since the structure is made possible, the surface on which the power semiconductor module is mounted on the cooler can be changed to one side or both sides depending on the required power of the motor, or the number of the cooler mounted on the power converter 1 can be changed. There is an effect that the power conversion device 1 can be optimized and downsized. Further, power semiconductor modules 71A and 72A, 71B and 72B, 71C and 72C mounted on both surfaces of one cooler are used so that their input / output terminals are symmetrical with each other with the cooler interposed therebetween. Therefore, the connection of the positive and negative electrodes (bus bar) of DC power can be minimized and facilitated.
[0025]
Next, as a third embodiment of the present invention, a case where a plurality of power semiconductor modules 71A to 76D equal to the number of phases of the motor 2 is mounted on one cooling surface 50 of the cooler 11 will be described with reference to FIGS. I will explain. FIG. 9 is a schematic diagram of electric power when driving an AC three-phase six-pole motor (six phases), and a switching control circuit for outputting an AC is omitted. FIG. 10 is a side view of the internal configuration of the power conversion device 1 showing the third embodiment. A significant difference from FIG. 3 is that power semiconductor modules 71A to 76A for six phases are arranged at intervals of 60 ° on one cooling surface 50 of the cooler 11, but four to drive one phase. The two power semiconductor modules 71A to 71D are used in the same manner. AC output (U-1 phase, V-1 phase, W-1 phase, U-2 phase, V-2 phase, W-2 phase) from the power conversion device 1 is AC output via current sensors 91 to 96. The terminals 31 to 36 are connected to the windings of the motor 2 through the structural member 102 on the end face of the motor 2 using electrodes (bus bars), as in FIG.
[0026]
Also in this case, since the power semiconductor modules 71A to 71D, 72A to 72D, 73A to 73D, 74A to 74D, 75A to 75D, and 76A to 76D are arranged radially around the drive shaft 4 at intervals of 60 °, the current sensor 91 -96 and the AC output terminals 31-36, each component can be arranged in an equal positional relationship between the six phases, and there is an effect that all surge voltages and heat generation can be made uniform.
[0027]
Moreover, since the center part of the coolers 11 and 12 is attached to the structural member 101 surrounding the drive shaft, the strength (rigidity) of the power conversion device 1 can be ensured. Further, a plurality of coolant passages 46 through which the coolant flows inside the coolers 11 and 12 are formed in a circular shape around the drive shaft 4 in the radial direction of the drive shaft 4. The power semiconductor modules 71A to 71D, 72A to 72D, 73A to 73D, 74A to 74D, 75A to 75D, and 76A to 76D that are mounted on the surface can be uniformly cooled.
[0028]
Also, power semiconductor modules for 6 phases can be mounted on one cooling surface of the cooler, power semiconductor modules can be mounted on both sides of the cooler, and the number of coolers mounted on the power conversion device 1 can be changed. Therefore, depending on the required power of the motor, the surface on which the power semiconductor module is attached to the cooler can be changed to one side or both sides, or the number of the cooler attached to the power converter 1 can be changed. There is an effect that the power conversion device 1 can be optimized and downsized.
[0029]
Furthermore, power semiconductor modules 71A and 71B, 72A and 72B, 73A and 73B, 74A and 74B, 75A and 75B, 76A and 76B, 71C and 71D, 72C and 72D, and 73C and 73D mounted on both sides of one cooler. 74C and 74BD, 75C and 75D, and 76C and 76D are mounted with power semiconductor modules whose input / output terminals are symmetrical to each other with the cooler interposed therebetween, so that the AC output electrode (bus bar) 21 To 26 and the connection of positive and negative electrodes (busbars) of DC power can be minimized and facilitated.
[Brief description of the drawings]
FIG. 1 is an external configuration diagram of an integrated structure of a power conversion device and a motor according to the present invention.
FIG. 2 is a schematic power diagram of an electric vehicle drive system using the power conversion device of the present invention.
FIG. 3 is a side view of the internal configuration of the power conversion device according to the first embodiment of the present invention.
FIG. 4 is a perspective view of a cooler of the power conversion device according to the first embodiment of the present invention.
FIG. 5 is a diagram showing a coolant passage pattern of the cooler of the power conversion device showing the first embodiment of the present invention.
FIG. 6 is a diagram showing a terminal arrangement of a power semiconductor module.
FIG. 7 is a schematic power diagram of U-phase power generation showing the first embodiment of the present invention.
FIG. 8 is a side view of an internal configuration of a power conversion device showing a second embodiment of the present invention.
FIG. 9 is a schematic electric power system diagram of an electric vehicle drive system using a power converter according to a third embodiment of the present invention.
FIG. 10 is a side view of the internal configuration of a power conversion device showing a third embodiment of the present invention.
[Explanation of symbols]
DESCRIPTION OF SYMBOLS 1 ... Power converter 2 ... Motor 4 ... Drive shaft 11, 12 ... Cooler 46 ... Coolant passage 50 ... Cooling surface 70a ... AC output terminal 70n ... Negative power source terminal 70p ... Positive power source terminals 71-73, 71A-71D, 72A-72D, 73A-73D, 74A-74D, 75A-75D, 76A-76D ... Power semiconductor module 101 ... Structural member surrounding drive shaft

Claims (7)

In the power converter that is arranged in series with the motor and integrated, and the motor shaft or drive shaft penetrates,
At least one cylindrical flat or polygonal flat cooler centered on the motor shaft or the drive shaft is provided, and the cooling surface of the cooler is perpendicular to the motor shaft or the drive shaft. to both sides of the cooling surface, mounting the power semiconductor module for supplying power to said motor,
And the terminal arrangement | positioning of the said power semiconductor module between both surfaces of the said cooling surface is a mutually symmetrical relationship on both sides of the said cooler, The power converter device characterized by the above-mentioned .   The power converter according to claim 1, wherein the cooler is attached to a structural member surrounding the motor shaft or the drive shaft.   The cooler has a coolant passage for radiating heat, and the coolant passage is circular around the motor rod or the drive shaft, and a plurality of the coolant passages are formed in a radial direction of the drive shaft. The power converter device according to claim 1.   In the power semiconductor module mounted on the cooler, the power semiconductor modules of each phase of AC three-phase are arranged radially on the cooling surface of one of the coolers centered on the motor shaft or the drive shaft. The power converter according to any one of claims 1 to 3 characterized by things. The number of pre-Symbol cooler Ru is attached to the power converter, the power converter according to claim 4, characterized in that determined by the necessary power of the motor. In the power converter that is arranged in series with the motor and integrated, and the motor shaft or drive shaft penetrates ,
At least one cylindrical flat or polygonal flat cooler centered on the motor shaft or the drive shaft is provided, and the cooling surface of the cooler is perpendicular to the motor shaft or the drive shaft. A power semiconductor module that supplies power to the motor is mounted on one or both surfaces of the cooling surface ,
The power semiconductor module to be mounted on the cooler is arranged on one cooling surface or on one cooler so that one phase of AC is radially arranged around the motor shaft or the drive shaft. This is a power conversion device.   Whether the cooling surface on which the power semiconductor module is mounted on the cooler is only one surface or both surfaces, or the number of the cooling device mounted on the power converter is determined by the number of phases of the motor. The power conversion device according to claim 6.

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