JP2019092282A - Vehicle power conversion device and smoothing capacitor unit - Google Patents

Abstract

To reduce the number of components and assembly man hour of a vehicle power conversion device.SOLUTION: A vehicle power conversion device comprises: a plurality of element units having a semiconductor switching element and being capable of configuring an inverter; and a smoothing capacitor unit for smoothing an input DC current to output it to the element units, and converts the DC power into three-phase AC power and output it. The element units and smoothing capacitor are electrically coupled by being fixed with a screw with each other and have a terminal connection section for making them a fixed state with each other.SELECTED DRAWING: Figure 1

Description

  Embodiments of the present invention relate to a power converter for a vehicle and a smoothing capacitor unit.

  In recent years, as a power conversion device, power saving has become an element that is closely watched in the world, and by using low loss SiC (silicon carbide) from Si (silicon) conventionally used for elements of power semiconductor modules The power conversion device with a reduced size and weight of the device has been put to practical use.

  By the way, in a power conversion device for vehicles such as VVVF (Variable Voltage Variable = AVAF) for railway vehicles, a power conversion module that converts a DC voltage into an AC voltage causes spikes due to current interruption generated at the time of switching operation. A configuration is known in which a smoothing capacitor is attached to a semiconductor element module through a laminated conductor in order to reduce a spike voltage because a voltage is generated.

Patent No. 5269259 gazette

In such a configuration, the smoothing capacitor and the semiconductor element module are connected by a laminated conductor which is stacked in two layers via an insulator, thereby reducing the inductance component while suppressing the temperature rise of the smoothing capacitor. Is also proposed.
However, when connection is performed via a laminate conductor, the number of parts increases, the number of assembly steps increases, and the cost increases.

  This invention is made in view of the above, Comprising: It aims at providing the power converter for vehicles and smoothing capacitor unit which can reduce the number of parts and the number of assembly processes.

  The vehicle power converter according to the embodiment includes a plurality of element units having a semiconductor switching element, capable of forming an inverter, and a smoothing capacitor unit that smoothes input DC power and outputs the smoothed element unit to the element unit. It is an electric power converter for vehicles which converts and outputs said direct-current power into three-phase alternating current power, and an element unit and a smoothing capacitor unit are electrically connected by fastening mutually with a screw, Terminal connection parts are provided.

FIG. 1 is a schematic configuration block diagram of a power conversion apparatus for a vehicle according to an embodiment. FIG. 2 is a schematic configuration diagram of the inverter unit. FIG. 3 is an external view of the smoothing capacitor unit. FIG. 4 is an explanatory view of the structure of the element unit. FIG. 5 is an explanatory diagram of a circuit configuration example of the inverter unit. FIG. 6 is an external view of the assembled state of the power converter for a vehicle. FIG. 7 is an external view of the power converter for a vehicle according to the second embodiment. FIG. 8 is an external view of the smoothing capacitor unit of the third embodiment. FIG. 9 is an enlarged view of a mounting portion of the current sensor. FIG. 10 is an external view of the assembled state of the power converter for a vehicle according to the fourth embodiment.

Embodiments will now be described in detail with reference to the drawings.
FIG. 1 is a schematic configuration block diagram of a power conversion apparatus for a vehicle according to an embodiment.
The vehicle power converter 10 controls an inverter unit 12 which converts DC power supplied from a DC lead or an AC lead via a converter unit and supplies it as a three-phase AC power to the motor 11, and the inverter unit 12 And a gate amplifier substrate 13 for

FIG. 2 is a schematic configuration diagram of the inverter unit.
The inverter unit 12 is connected to a smoothing capacitor unit 21 for smoothing input DC power, an inverter main body 22 connected to the smoothing capacitor unit 21 and outputting a three-phase alternating current, and a three-phase alternating current A U-phase current sensor 23 for measuring a U-phase current and a W-phase current sensor 24 for measuring a W-phase current constituting a three-phase alternating current are provided.

  In this configuration, the inverter main body 22 includes a U-phase arm 41U, a V-phase arm 41V, and a W-phase arm 41W.

FIG. 3 is an external view of the smoothing capacitor unit.
3 (a) is a front view, FIG. 3 (b) is a plan view, and FIG. 3 (c) is a side view.
The smoothing capacitor unit 21 is a thin plate block-shaped capacitor 31 and a pair of DC side terminals 32P and 32N provided on one end side of the capacitor 31 and connected to the pair of terminals of the capacitor 31 and the other end of the capacitor 31. And three three-phase alternating current side terminals 33-1 to 33-6 connected to each of the pair of terminals of the capacitor 31.

  Here, the three three-phase alternating current terminals 33-1, 33-3, 33-5 function as three-phase alternating current first terminals, and the other three three-phase alternating current terminals 33-2, 33 -4, 33-6 function as a three-phase alternating current side second terminal.

The U-phase arm unit 41U includes an element unit 41UU configuring a U-phase upper arm unit and an element unit 41UL configuring a U-phase lower arm unit.
The V-phase arm 41V includes an element unit 41VU constituting a V-phase upper arm and an element unit 41VL constituting a V-phase lower arm.
The W-phase arm unit 41W includes an element unit 41WU configuring a U-phase upper arm unit and an element unit 41WL configuring a W-phase lower arm unit.

In the following description, when it is not necessary to identify the element unit 41UU, 41UL, 41VU, 41VL, 41WU, 41WL, the element unit is denoted by reference numeral 41X.
Here, since the element units 41UU, 41UL, 41VU, 41VL, 41WU, and 41WL have the same configuration, the element unit 41UU will be described below as an example.

FIG. 4 is an explanatory view of the structure of the element unit.
FIG. 4A is a plan view of the element unit 41U.
The element unit 41UU has a thin plate shape, and a pair of the element units 41UU that are provided so as to protrude from the substantially rectangular main body BD from the first direction (left direction in FIG. 4A) and are electrically connected to each other 1 A pair of input / output terminals T1 and a pair of electrical connections which are provided to protrude from the main body BD in a second direction (right direction in FIG. # (A) in the direction opposite to the first direction). And a second input / output terminal T2.

  Screw holes SC1 for fixing to the cooling member are provided at the four corners of the body BD of the element unit 41UU, and smoothing capacitors or three-phase AC outputs are provided for each of the first input / output terminal T1 and the second input / output terminal T2. A screw hole SC2 is provided in which the terminals are connected electrically and physically.

FIG. 4B is a circuit diagram of the element unit 41U.
The element unit 41UU includes an IGBT (Insulated Gate Bi-polar Transistor) 35 and a diode (return diode) 36 connected in parallel. The collector terminals of the IGBTs 35 are commonly connected to the first input / output terminal T1, and the emitters of the IGBTs 35 are connected. The terminal is commonly connected to the second input / output terminal T2.

FIG. 5 is an explanatory diagram of a circuit configuration example of the inverter unit.
The first input / output terminal T1 of the element unit 41U is screwed to the three-phase alternating current side terminal 33-1 of the smoothing capacitor unit 21. As a result, the collector terminal of the IGBT 35 and the cathode terminal of the diode 36 are connected to the three-phase AC terminal 33-1.

  The second input / output terminal T2 of the element unit 41UL is screwed to the three-phase alternating current side terminal 33-2 of the smoothing capacitor unit 21. As a result, the emitter terminal of the IGBT 35 and the anode terminal of the diode 36 are connected to the three-phase AC terminal 33-2.

  Furthermore, the second input / output terminal T2 of the element unit 41UU and the first input / output terminal T1 of the element unit 41UL are connected in common, and the element unit 41UU and the element unit 41UL constitute a U-phase arm portion.

The first input / output terminal T1 of the element unit 41VU is screwed to the three-phase alternating current side terminal 33-3 of the smoothing capacitor unit 21. As a result, the collector terminal of the IGBT 35 and the cathode terminal of the diode 36 are connected to the three-phase AC terminal 33-3.
The second input / output terminal T2 of the element unit 41VL is screwed to the three-phase alternating current side terminal 33-4 of the smoothing capacitor unit 21. As a result, the emitter terminal of the IGBT 35 and the anode terminal of the diode 36 are connected to the three-phase AC terminal 33-4.

  Further, the second input / output terminal T2 of the element unit 41VU and the first input / output terminal T1 of the element unit 41VL are commonly connected, and the element unit 41VU and the element unit 41VL constitute a V-phase arm portion.

  The first input / output terminal T1 of the element unit 41WU is screwed to the three-phase alternating current side terminal 33-5 of the smoothing capacitor unit 21. As a result, the collector terminal of the IGBT 35 and the cathode terminal of the diode 36 are connected to the three-phase AC terminal 33-5.

The second input / output terminal T2 of the element unit 41WL is screwed to the three-phase alternating current side terminal 33-6 of the smoothing capacitor unit 21. As a result, the emitter terminal of the IGBT 35 and the anode terminal of the diode 36 are connected to the three-phase AC terminal 33-6.
Further, the second input / output terminal T2 of the element unit 41WU and the first input / output terminal T1 of the element unit 41WL are commonly connected, and the element unit 41WU and the element unit 41WL constitute a W-phase arm portion.

FIG. 6 is an external view of the assembled state of the power converter for a vehicle.
6 (a) is a front view, FIG. 6 (b) is a plan view, and FIG. 6 (c) is a side view.
As shown in FIG. 6, the power conversion apparatus 10 for a vehicle has four screw holes SC1 so that the cooling surface 51 of the six element units 41UU, 41UL, 41VU, 41VL, 41WU, 41WL are on the cooling device 52 side. It is screwed to the cooling device via

  Furthermore, the first input / output terminal T1 or the second terminal in the element units 41UU, 41UL, 41VU, 41VL, 41WU, 41WL are connected in three phases of the gate amplifier substrate 13 and the smoothing capacitor unit 21 in the connection state shown in FIG. It is screwed integrally with the AC side terminal.

  As described above, according to the present embodiment (the first embodiment), the capacitor unit, the gate amplifier substrate 13 and the gate amplifier substrate perform physical fixing and circuit connection by screwing. Therefore, the number of parts and the number of assembling steps can be reduced without separately providing a wiring member such as a conventional laminated conductor, and as a result, the manufacturing cost can also be reduced.

FIG. 7 is an external view of the power converter for a vehicle according to the second embodiment.
In FIG. 7, the same parts as in FIG. 6 (c) are assigned the same reference numerals.
Power conversion device 10A for vehicles is via four screw holes so that the cooling surface of 12 element units (2 units of element units 41UU, 41UL, 41VU, 41VL, 41WU, 41WL) is on the cooling device side. While being screwed to the cooling device, the three-phase AC power side terminal of the smoothing capacitor unit 21 is screwed together with the gate amplifier substrate in each of two sets of six element units.
The second embodiment differs from the power conversion device according to the first embodiment in that three-phase AC power is supplied to a plurality of loads (for example, a plurality of motors). More specifically, two inverter units 12 are provided, ie, two smoothing capacitor units 21 and twelve element units 41.

  Also in the second embodiment, as in the first embodiment, the smoothing capacitor unit 21, the gate amplifier substrate 13, and the gate amplifier substrate perform physical fixing and circuit connection by screwing. It is possible to supply three-phase AC power to a plurality of loads while reducing the number of parts, the number of assembling steps, and the manufacturing cost without separately providing a wiring member such as the laminate conductor described above.

In each of the above embodiments, the U-phase current sensor 23 and the W-phase current sensor 24 are provided to measure the three-phase alternating current output from the three-phase alternating current power side terminal. The embodiment is an embodiment in which an alternating current detection sensor is provided in a smoothing capacitor unit having a three-phase alternating current power side terminal.
By the way, when providing a current sensor, there is a method of providing a sheet metal space for attaching the current sensor to the frame of the ceiling surface of the power conversion device and attaching the current sensor, but increasing the number of parts, upsizing of the device, wiring Due to the increase in the number of assembly steps due to the complexity of

FIG. 8 is an external view of the smoothing capacitor unit of the third embodiment.
FIG. 9 is an enlarged view of a mounting portion of the current sensor.
Therefore, in the third embodiment, two sets of screw seat plates 63 for attaching the two current sensors 61 and 62 are provided to the smoothing capacitor unit 60 having the same configuration as the smoothing capacitor unit 21. The fixing bolt 64 is fixed by a weld nut (welding nut) 65 and can be attached.

  Therefore, according to the third embodiment, since the current sensors 61 and 62 can be integrally attached only by attaching the smoothing capacitor unit 50, the number of parts can be reduced, the number of assembling steps can be reduced, the cost can be reduced, and the like. The device can be miniaturized.

The fourth embodiment is an embodiment in which a PWM control board is integrated with a power conversion apparatus for a vehicle.
FIG. 10 is an external view of the assembled state of the power converter for a vehicle according to the fourth embodiment.
In FIG. 10, parts similar to those in FIG. 6 (b) are given the same reference numerals.
As shown in FIG. 10, a plurality of (for example, six) power conversion devices 10B for a vehicle are screwed to the cooling device 52 via the four screw holes SC1 such that the cooling surface is on the cooling device side. The element unit, the PWM control board 72 connected to the plurality of element units 41X via the wiring board 71, and the plurality of elements integrally with the wiring board 71 via the wiring board 71 to the plurality of element units 41X It has a three-phase alternating current side terminal and a smoothing capacitor unit 21 screwed to be electrically connectable to the unit 41X.

As described above, according to the fourth embodiment, when the PWM control board 62 integrated with the wiring board 71 is electrically connected to the element unit and assembled, the smoothing capacitor unit 21 is attached simultaneously. Since the process can be performed, the number of assembling steps can be reduced.
Further, since the wiring substrate 71 is directly connected to the PWM control substrate 72 and integrally connected to the element unit 41X, the miniaturization can be facilitated.

  In the above description, the element unit 41X is configured to include the IGBT and the diode (reflux diode) capable of forming the upper arm or the lower arm, but to form an element unit integrally including the upper arm and the lower arm It is also possible to

  While certain embodiments have been described, these embodiments have been presented by way of example only, and are not intended to limit the scope of the invention. These novel embodiments can be implemented in various other forms, and various omissions, substitutions, and modifications can be made without departing from the scope of the invention. These embodiments and modifications thereof are included in the scope and the gist of the invention, and are included in the invention described in the claims and the equivalent scope thereof.

10, 10A, 10B Power converter for vehicle 11 Motor 12 Inverter unit 13 Gate amplifier board 21 Smoothing capacitor unit 22 Inverter main body 23 U phase current sensor 24 W phase current sensor 31 Capacitor 32P DC side terminal 33 Three phase AC side terminal 35 IGBT
36 diode 41 element unit 41 U U-phase arm part 41 V V-phase arm part 41 W W-phase arm part 41 UL, 41 UU, 41 VL, 41 VU, 41 WL, 41 WU element unit 41 X element unit 50 smoothing capacitor unit 51 cooling surface 52 cooling device 60 smoothing capacitor unit 61 current sensor 62 PWM control board 63 screw seat plate 64 fixing bolt 71 wiring board 72 PWM control board BD main body SC1 screw hole SC2 screw hole T1 first input / output terminal T2 second input / output terminal VVVF for railway vehicles

Claims (7)

The device includes: a plurality of element units each having a semiconductor switching element and capable of configuring an inverter; and a smoothing capacitor unit that smoothes input DC power and outputs the smoothed DC power to the element unit; Power conversion equipment for vehicles that convert to
The element unit and the smoothing capacitor unit are electrically connected by fastening them to each other with screws, and provided with terminal connection portions that fix each other.
Power converter for vehicles. The smoothing capacitor unit includes a pair of DC side terminals to which the DC power is input;
A three-phase alternating current side terminal for outputting the three-phase alternating current power;
The power converter for vehicles according to claim 1. A plurality of sets of the plurality of element units and the smoothing capacitor unit;
The DC terminals of the plurality of smoothing capacitor units are commonly connected,
The power converter for vehicles according to claim 2. The smoothing capacitor unit has a mounting screw, and includes a current sensor for detecting the current of the three-phase AC power, and a screw seat to which the current sensor is attached.
The power converter for vehicles according to any one of claims 1 to 3. The power converter for vehicles performs power conversion by PWM control,
A wiring board,
A PWM board connected to the element unit via the wiring board to control the element unit;
Equipped with
The power converter for vehicles according to any one of claims 1 to 4. A smoothing capacitor unit capable of supplying smooth DC power to a power conversion unit that receives DC power and is provided in a subsequent stage and converts the DC power into three-phase AC power,
A pair of DC side terminals to which the DC power is input;
A three-phase alternating current first terminal for outputting the three-phase alternating current power;
A three-phase alternating current second terminal that is paired with the three-phase alternating current first terminal and outputs the three-phase alternating current power;
A capacitor connected between the pair of DC side terminals;
One of the pair of DC side terminals is connected to the three-phase AC side first terminal,
The other of the pair of direct current side terminals is connected to the three-phase alternating current side second terminal,
Smoothing capacitor unit. The smoothing capacitor unit has a mounting screw, and includes a current sensor for detecting the current of the three-phase AC power, and a screw seat to which the current sensor is attached.
The smoothing capacitor unit according to claim 6.

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