JP6416061B2 - Power converter - Google Patents

Description

  The present invention relates to a power conversion device.

  A power conversion device for driving a vehicle such as a hybrid vehicle or an electric vehicle includes, for example, a power semiconductor module for three phases that incorporates an upper / lower arm series circuit of an inverter circuit. The power semiconductor module has a power supply terminal connected to the power supply board and a signal terminal connected to the control circuit board. The power supply board and the control circuit board are formed with openings through which the respective terminals are inserted, and the respective terminals of the power semiconductor module are joined by soldering or welding while being inserted into the openings. (For example, refer to Patent Document 1).

JP, 2014-050118, A

  In the configuration in which each terminal of the power semiconductor module is connected to the circuit board by soldering or welding, workability is not good. Therefore, productivity can be improved by using a connection structure such as a connector that maintains electrical holding only by inserting a terminal. However, in the connection using the connector, the insertion force when inserting and connecting a large number of terminals formed on the power semiconductor module into the connector increases, and the circuit board may be deformed or damaged. .

The power conversion device according to the present invention includes a power semiconductor module having a signal terminal, a current sensor having a current sensor terminal, a first connection connected to the signal terminal, and a second connected to the current sensor terminal. of a control circuit board having a connection portion, having the control circuit board and parallel-arranged flat upper surface, and a holding member for holding the power semiconductor module and the current sensor, the said retaining member The height position of the tip of the current sensor terminal with respect to the upper surface is set to a position higher than the height position of the tip of the signal terminal with respect to the upper surface of the holding member.

  ADVANTAGE OF THE INVENTION According to this invention, a deformation | transformation of the control circuit board at the time of inserting a signal terminal and a current sensor terminal in a connection part can be suppressed.

The disassembled perspective view which shows one Embodiment of the power converter device of this invention. (A) is an enlarged view of the vicinity of the terminal portion of the power semiconductor module shown in FIG. 1, (B) is a circuit diagram showing an example of a circuit built in the power semiconductor module. FIG. 2 is a top view of the control circuit board illustrated in FIG. 1. The figure seen from IV-IV of FIG. 1 which shows the state before inserting each terminal of a power semiconductor module and a current sensor in the connector provided in the control circuit board. The figure which shows the state which inserts each terminal of the power semiconductor module and current sensor which were illustrated by FIG. 4 in the connector provided in the control circuit board using the jig | tool. (A) is typical sectional drawing which shows the state which penetrates a terminal to a connector, (B) is a characteristic view which shows the relationship between the displacement amount of a terminal, and insertion force. (A), (B) is a figure for demonstrating the relationship between the amount of displacement of a terminal, and insertion force by one embodiment of this invention. (A), (B) is a figure for demonstrating the relationship between the displacement amount of a terminal and insertion force of a comparative product.

-First embodiment-
(Overall structure of power converter)
Hereinafter, an embodiment of the present invention will be described with reference to FIGS.
FIG. 1 is an exploded perspective view of an embodiment of a power conversion device of the present invention.
The power conversion apparatus 1 includes seven power semiconductor modules 100a to 100g (100g is not shown), three temperature sensors 300a to 300c, a boost reactor 700, a molded bus bar 500, and a control circuit board 400. Yes. Although not shown, power semiconductor modules 100a to 100g, temperature sensors 300a to 300c, step-up reactor 700, mold bus bar 500, and control circuit board 400 are formed with cooling passages for cooling power semiconductor modules 100a to 100g. Housed in a housing.

  Each of the power semiconductor modules 100a to 100c includes, for example, a U-phase, V-phase, and W-phase upper and lower arm series circuit that drives a motor generator (not shown). The power semiconductor modules 100d to 100f incorporate, for example, U-phase, V-phase, and W-phase upper and lower arm series circuits that drive auxiliary motors such as air conditioner compressors and hydraulic pumps. The power semiconductor module 100g is disposed below the molded bus bar 500, is connected to the boost reactor 700, and constitutes a boost chopper together with a switching device and a diode (not shown). Each of the power semiconductor modules 100a to 100g has a similar structure, and is hereinafter referred to as a power semiconductor module 100 as appropriate.

  Each of the current sensors 300a and 300b has three current sensor units (not shown) each having three current sensor terminals 301a to 301c. The current sensor 300c has one current sensor unit having three current sensor terminals 301a to 301c. The current sensors 300a to 300c basically have the same structure, and are hereinafter referred to as the current sensor 300 as appropriate.

Current sensors 300 a to 300 c are attached to molded bus bar 500.
Current sensors 300a to 300c each measure a current flowing through the bus bar of molded bus bar 500 in the current sensor unit.
As shown in FIG. 2, the power supply terminals 101 to 103 and the signal terminals 111 to 113 and 121 to 125 of the power semiconductor modules 100 a to 100 g are inserted through the opening of the mold bus bar 500 and above the mold bus bar 500. Is protruding. The power semiconductor modules 100a to 100g and the boost reactor 700 are fixed to the bottom inner surface of a casing having a cooling channel (not shown). The power semiconductor modules 100a to 100g and the boost reactor 700 may be held by the molded bus bar 500.

2A is an enlarged view of the vicinity of the terminal portion of the power semiconductor module shown in FIG. 1, and FIG. 2B is a circuit diagram showing an example of a circuit built in the power semiconductor module.
With reference to FIGS. 2A and 2B, the power semiconductor module 100 will be described in association with an electric circuit.
As illustrated in FIG. 2B, the power semiconductor module 100 includes two IGBTs 110 and 120 and two diodes 130 and 140. The IGBT 110 and the diode 130 constitute an upper arm circuit. The IGBT 120 and the diode 140 constitute a lower arm circuit.
The emitter of IGBT 110 and the collector of IGBT 120 are connected. The connection point is connected to the connection point of the anode of the diode 130 and the cathode of the diode 140, and the AC output terminal 102 is connected. The collector of IGBT 110 and the cathode of diode 130 are connected to DC positive input terminal 101. The emitter of IGBT 120 and the anode of diode 130 are connected to DC negative input terminal 103. The gates of the IGBTs 110 and 120 are connected to the gate terminals 111 and 121, respectively, and the emitters of the IGBTs 110 and 120 are connected to the emitter terminals 112 and 122, respectively.
Note that T in FIG. 2B represents an IGBT, and D represents a diode.

  The terminals 101 to 103, 111, 112, 121, and 122 illustrated in FIG. 2B are mounted on the power semiconductor module 100 as illustrated in FIG. However, as illustrated in FIG. 2A, two DC negative input terminals 103 are formed as 103 a and 103 b and are electrically connected inside the power semiconductor module 100. Further, two DC positive input terminals 101 are formed as 101 a and 101 b and are electrically connected inside the power semiconductor module 100. In FIG. 2A, four terminals 113, 123 to 125 not shown in FIG. 2B are sensor signal terminals for detecting overcurrent and overtemperature of the IGBTs 110 and 120. It is. Each of the terminals 101 to 103, 111 to 113, and 121 to 125 is insert-molded into the auxiliary mold body 134 with the tip side protruding. Although not shown, the upper and lower arm circuits connected to the terminals 101 to 103, 111 to 113, and 121 to 125 are fixed to the conductive plate and are placed on the upper part of the module case 131 (see FIGS. 1 and 4). It is accommodated in the module case 131 from the formed opening 133. In this state, the resin case 132 is filled in the module case 131 and sealed. Each terminal 101-103 for power supplies is connected to the bus bar not shown provided in the mold bus bar 500 by TIG welding, for example.

FIG. 3 is a top view of the control circuit board shown in FIG. In the following description, reference is also made to FIG.
On the control circuit board 400, seven first connectors 410 corresponding to the signal terminals 121 to 125 of the power semiconductor modules 100a to 100g and seven second connectors 420 corresponding to the signal terminals 111 to 113 are attached. ing. Further, seven third connectors 430 corresponding to the current sensor terminals 301a to 301c of the current sensors 300a to 300c are attached to the control circuit board 400.

  FIG. 1 shows an assembling jig 800. The assembling jig 800 is disposed above the control circuit board 400, and a plurality of positioning pins 801 projecting toward the control circuit board 400 are provided on the lower surface. The control circuit board 400 is provided with positioning holes 401 (see FIG. 3) at positions corresponding to the positioning pins 801 of the assembly jig 800. The mold bus bar 500 is provided with a boss 530 having a boss hole 531 formed at a position corresponding to each positioning pin 801 of the assembly jig 800. An assembling method using the assembling jig 800 will be described later.

4 is a view as seen from IV-IV in FIG. 1, showing a state before each terminal of the power semiconductor module and the current sensor is inserted into the connector provided on the control circuit board. It is a figure which shows the state which inserts each terminal of the power semiconductor module and current sensor which were illustrated in (2) into the connector provided in the control circuit board using the jig | tool.
When the signal terminals 121 to 125 and 111 to 113 of the power semiconductor module 100 and the current sensor terminals 301a to 301c of the current sensor 300 are connected to the first to third connectors 410, 420, and 430, respectively, the control circuit board 400 is used. Are arranged substantially parallel to the flat upper surface of the mold bus bar 500. At this time, in one embodiment of the present invention, the connection between the current sensor terminals 301 a to 301 c of the current sensor 300 and the third connector 430 is connected to the signal terminals 121 to 125 of the power semiconductor module 100 and the first connector 410. And the connection between the signal terminals 111 to 113 of the power semiconductor module 100 and the second connector 420 are performed.

For this reason, the positions of the tips of the current sensor terminals 301a to 301c are positioned higher than the positions of the tips of the signal terminals 121 to 125 and 111 to 113, that is, higher than the top surface of the mold bus bar 500. Yes. In order to do this, for example, the following configuration is adopted.
i) The length of the current sensor terminals 301a to 301c is made larger than the length of the signal terminals 111 to 113 and 121 to 125, or
ii) The height position of the side surface 311 where the current sensor terminals 301a to 301c of the current sensor 300 are exposed is higher than the height position of the side surface 135 where the signal terminals 111 to 113 and 121 to 125 of the auxiliary mold body 134 are exposed. Make it high.
It is good also as a structure which satisfies said i) and ii) simultaneously.

FIG. 6A is a schematic cross-sectional view showing a state where the terminal is inserted into the connector, and FIG. 6B is a characteristic diagram showing a relationship between the displacement amount of the terminal and the insertion force.
6A, the signal terminals 111 to 113 and 121 to 125 are represented as signal terminals 111, and the connection between the signal terminals 111 and the connector 420 will be described.
The connector 420 is fixed to the molded bus bar 500. The connector 420 has a pair of connection terminals 421 and 422 provided in the pin insertion hole 429. The connection terminal 422 is curved in a direction in which the lower end side is close to the connection terminal 421 side. A bent portion 425 that is bent in a “<” shape is formed at the tip of the curved portion. That is, the bent portion 425 has an inclined portion 425a at the tip thereof that is inclined in a direction away from the connection terminal 421. The signal terminal 111 is a pin-shaped member, and the upper end has a truncated cone shape. That is, an inclined portion 111 a is formed at the upper end of the signal terminal 111.

  When the signal terminal 111 is displaced upward from the position of the solid line in FIG. 6, that is, as shown by the dotted line, the inclined portion 111 a of the signal terminal 111 becomes the inclined portion 425 a of the connecting terminal 422. Abut. The signal terminal 111 is displaced while expanding the connection terminal 422. When the inclined portion 111a of the signal terminal 111 passes through the inclined portion 425a of the connection terminal 422, the insertion force is maximum, in other words, the insertion force peak. The relationship between the displacement of the connection terminal 422 and the insertion force of the connection terminal 422 at this time is shown in FIG.

FIGS. 7A and 7B are diagrams for explaining the relationship between the amount of displacement of the terminal and the insertion force according to one embodiment of the present invention.
In one embodiment of the present invention, as shown in FIG. 7A, the height positions of the tips of the current sensor terminals 301a to 301c are the heights of the tips of the signal terminals 111 to 113 and 121 to 125, respectively. It is located above the vertical position. Thereby, after the current sensor terminals 301a to 301c are connected to the third connector 430, the signal terminals 121 to 125 and 111 to 113 are connected to the first and second connectors 410 and 420, respectively. Therefore, the insertion force peak position between the current sensor terminals 301a to 301c and the third connector 430, and the insertion force peak position between the signal terminals 121 to 125 and 111 to 113 and the first and second connectors 410 and 420, Shift, in other words, do not overlap.

  In one embodiment of the present invention, the maximum load acting on the control circuit board 400 is the sum n = 3 of the insertion force peak values (three locations) between the current sensor terminals 301a to 301c and the third connector 430, or The sum n of the insertion force peak values (eight locations) between the signal terminals 121 to 125 and 111 to 113 of the power semiconductor module 100 and the first and second connectors 410 and 420 is n = 8.

  FIGS. 8A and 8B are diagrams for explaining the relationship between the displacement amount of the terminal and the insertion force in the comparative product. In the comparative product, as shown in FIG. 8A, the height positions of the tips of the current sensor terminals 301a to 301c are the same as the height positions of the tips of the signal terminals 111 to 113 and 121 to 125. It has a structure. In this structure, the connection between the current sensor terminals 301a to 301c and the third connector 430 and the connection between the signal terminals 121 to 125 and 111 to 113 and the first and second connectors 410 and 420 have the same timing. Become. That is, the insertion force peak position between the current sensor terminals 301a to 301c and the third connector 430 and the insertion force peak position between the signal terminals 121 to 125 and 111 to 113 and the first and second connectors 410 and 420 are determined. , Superimpose.

In the comparative product, the maximum load acting on the control circuit board 400 is the insertion force peak value (eight locations) between the signal terminals 121 to 125 and 111 to 113 of the power semiconductor module 100 and the first and second connectors 410 and 420. And the sum n of the insertion force peak values (three locations) of the current sensor terminals 301a to 301c and the third connector 430 is n = 11.
Therefore, the maximum load acting on the control circuit board 400 is larger in the comparative product than in the embodiment of the present invention. In FIG. 7B, the maximum load acting on the control circuit board 400 of the comparative product is shown by a dotted line in contrast to the maximum load acting on the control circuit board 400 in the embodiment of the present invention.

As described above, in the embodiment of the present invention, when the signal terminals 121 to 125 and 111 to 113 of the power semiconductor module 100 are connected to the first and second connectors 410 and 420, and the current sensor terminals 301a to 301c. When connecting the third connector 430 and the third connector 430, the load acting on the control circuit board 400 can be reduced. In the embodiment shown in FIG. 1, seven power semiconductor modules 100 a to 100 g and seven current sensor units (not shown) having current sensor terminals 301 a to 301 c are mounted on the control circuit board 400. Therefore, in the structure in which all the power semiconductor modules 100a to 100g and the current sensors 300a to 300c are simultaneously connected to the first to third connectors 410, 420, and 430 as in the comparative product, the total sum of the insertion force peak values is very large. It will be big.
However, according to the embodiment of the present invention, it is possible to prevent the control circuit board 400 from being greatly deformed or damaged due to such insertion force. In addition, when a large deformation occurs in the control circuit board 400, solder cracking or solder peeling occurs. However, since such solder cracking or solder peeling due to the deformation of the control circuit board 400 is suppressed, reliability is improved. Can be planned.

With reference to FIGS. 4 and 5, an efficient assembly method for assembling the control circuit board 400 to the power semiconductor modules 100a to 100g and the current sensors 100a to 100c will be described.
As shown in FIG. 4, the control circuit board 400 to which the first to third connectors 410, 420, and 430 are attached is disposed on the molded bus bar 500. Then, as shown in FIG. 5, an assembling jig 800 is disposed on the mold bus bar 500. A boss 530 having a plurality of boss holes 531 is formed in the mold bus bar 500. As shown in FIG. 1, the boss 530 having the boss hole 531 is in the vicinity of the signal terminals 111 to 113 and 121 to 125 of the power semiconductor modules 100a to 100g and the current sensor terminals 301a to 301c of the current sensors 300a to 300c. It is provided in the vicinity.

  As shown in FIG. 5, the positioning pins 801 of the assembly jig 800 are inserted into the positioning holes 401 of the control circuit board 400, and the positioning pins 801 protrude from the lower surface of the control circuit board 400. In this state, that is, with each positioning pin 801 of the assembly jig 800 protruding from the lower surface of the control circuit board 400, the assembly jig 800 and the control circuit board 400 are moved and assembled. The tips of the positioning pins 801 of the jig 800 are aligned with the boss holes 531 of the mold bus bar 500, and the tip portions of the positioning pins 801 are inserted into the boss holes 531. Then, the control circuit board 400 is pushed down using the positioning pins 801 of the assembly jig 800 as a guide. Thereby, the current sensor terminals 301a to 301c of the current sensors 300a to 300c are connected to the third connector 430. Further, the signal terminals 121 to 125 and 111 to 113 of the power semiconductor modules 100a to 100g are connected to the first and second connectors 410 and 420, respectively.

  At this time, as described above, the insertion force peak position between the current sensor terminals 301a to 301c and the third connector 430, the signal terminals 121 to 125, 111 to 113, and the first and second connectors 410 and 420 are connected. The insertion force peak position does not overlap. In this assembly, the control circuit board 400 is moved downward using the positioning pins 801 of the assembly jig 800 as a guide. For this reason, the inclination of the control circuit board 400 can be eliminated. Boss holes 531 through which the positioning pins 801 of the assembly jig 800 are inserted are formed in the vicinity of the signal terminals 111 to 113, 121 to 125 and the current sensor terminals 301a to 301c. For this reason, the connection between the signal terminals 121 to 125 and 111 to 113 and the first and second connectors 410 and 420 and the connection between the current sensor terminals 301 a to 301 c and the third connector 430 are accurate. That is, all seven insertion force peak positions are aligned.

According to one embodiment of the present invention, the following effects can be obtained.
(1) The tips of the signal terminals 111 to 113 and 121 to 125 of the power semiconductor modules 100a to 100g and the tips of the current sensor terminals 301a to 301c of the current sensors 300a to 300c are the tips of the signal terminals 111 to 113 and 121 to 125. Is superimposed on the insertion force peak position when the terminal is inserted into the first and second connectors 410 and 420 and the insertion force peak position when the tips of the current sensor terminals 301a to 301c are inserted into the third connector 430. It is set not to. For this reason, the load which acts on the control circuit board 400 can be reduced, and the deformation | transformation of the control circuit board 400 can be suppressed or a damage can be prevented. In addition, since deformation of the control circuit board 400 is suppressed, solder cracking and solder peeling that occur with the deformation of the control circuit board 400 can be prevented, and reliability can be improved.

(2) The height positions of the tips of the current sensor terminals 301a to 301c with respect to the upper surface of the mold bus bar 500 are set higher than the height positions of the tips of the signal terminals 111 to 113 and 121 to 1225 with respect to the upper surface of the mold bus bar 500. Has been. That is, the timing at which the current sensor terminals 301a to 301c are inserted into the third connector 430 is earlier than the timing at which the signal terminals 121 to 125 and 111 to 113 are inserted into the first and second connectors 410 and 420. . The current sensor needs to have a highly accurate set position in order to ensure detection accuracy. By setting the timing at which the current sensor terminals 301a to 301c are inserted into the third connector 430 first, the positional accuracy of the current sensor terminals 301a to 301c with respect to the current sensor portions of the current sensors 300a to 300c is increased, and the detection accuracy is increased. Can be secured.

  In the above-described embodiment, the timing at which the current sensor terminals 301a to 301c of all the current sensors 300a to 300c are inserted into the third connector 430 is the signal terminals 111 to 113 of all the power semiconductor modules 100a to 100g. , 121 to 125 are illustrated as a structure ahead of the timing of insertion through the first or second connector 410, 420. However, the timing at which the current sensor terminals 301a to 301c of only some of the current sensors 300a to 300c are inserted into the third connector 430 is the timing of all the power semiconductor modules 100a to 100g or some of the power semiconductor modules 100a to 100g. You may make it the signal terminals 111-113, 121-125 come ahead of the timing inserted in the 1st or 2nd connector 410,420.

  Alternatively, if current detection accuracy by the current sensors 300a to 300c can be ensured, the timing at which the current sensor terminals 301a to 301c of the current sensors 300a to 300c are inserted into the third connector 430 is the power semiconductor modules 100a to 100g. You may make it the signal terminals 111-113, 121-125 come after the timing inserted in the 1st or 2nd connector 410,420.

  In the said one Embodiment, it illustrated as a structure which has arrange | positioned the mold bus bar 500 on the power semiconductor modules 100a-100g. However, the bus bar that electrically connects the power semiconductor modules 100a to 100g and the holding member that holds the power semiconductor modules 100a to 100g may be separate members.

  In the one embodiment, the current sensors 300a to 300c are exemplified as a three-terminal structure having the current sensor terminals 301a to 301c. However, a current sensor having a terminal structure with three or more terminals can also be applied.

  In the above-described embodiment, the first to third connectors 410, 420, and 430 are illustrated as a structure attached to the control circuit board 400. However, the connector portion may be formed integrally with the control circuit board 400, or only the connection terminals 421 and 422 may be provided on the control circuit board 400. The point is that the control circuit board 400 may be provided with a connection portion.

  In the said one Embodiment, it illustrated as a power converter circuit provided with the three power semiconductor modules 100a-100c provided with the function as a three-phase arm circuit. However, the present invention can be applied to the power conversion device 1 including one power semiconductor module 100.

  In the said embodiment, it illustrated as an inverter circuit using IGBT. However, the present invention can be applied to an inverter circuit using a thyristor, a GTO (Gate Turn Off Thyristor) or the like instead of the IGBT.

  Further, the present invention can be applied not only to an inverter circuit that performs DC-AC conversion but also to a matrix converter that performs AC-AC conversion.

  The structure of the power semiconductor module 100 and the structure of the connection terminals 421 and 422 of the connectors 410, 420, and 430 are not limited to those exemplified in the above embodiment. Other embodiments conceivable within the scope of the technical idea of the present invention are also included in the scope of the present invention.

DESCRIPTION OF SYMBOLS 1 Power converter device 100, 100a-100g Power semiconductor module 101-103 Power supply terminal 101, 101a, 101b DC positive input terminal 103, 103a, 103b DC negative input terminal 111-113 Signal terminal 121-125 Signal terminal 135 Side (signal terminal exposed side)
300, 300a to 300c Current sensors 301a to 301c Current sensor terminal 400 Control circuit board 401 Positioning hole (positioning opening)
410 1st connector (1st connection part)
420 2nd connector (1st connection part)
430 Third connector (second connection portion)
500 Mold bus bar (holding member)
531 Boss hole (positioning opening)
800 Assembly jig 801 Positioning pin

Claims (4)

A power semiconductor module having a signal terminal;
A current sensor having a current sensor terminal;
A control circuit board having a first connection connected to the signal terminal and a second connection connected to the current sensor terminal ;
A holding member for holding the power semiconductor module and the current sensor; and a flat upper surface arranged in parallel with the control circuit board .
The power conversion device , wherein a height position of the tip of the current sensor terminal with respect to the upper surface of the holding member is set to a position higher than a height position of the tip of the signal terminal with respect to the upper surface of the holding member . The power conversion device according to claim 1 ,
The power semiconductor module has a signal terminal exposed side surface from which the signal terminal is exposed,
The current sensor has a current sensor terminal exposed side surface that exposes the current sensor terminal,
at least,
i) the height position of said signal terminals exposed side surface to said upper surface of said retaining member said current sensor terminals exposed sides are different, and ii) the length of the previous SL signal terminal exposed side surface to the tip of the signal terminals and said length to the tip of the front Symbol current sensor terminal exposed side the current sensor terminal from is provided with one different power conversion device. The power conversion device according to claim 2,
The height position of the current sensor terminal exposed side surface with respect to the upper surface of the holding member is higher than the height position of the signal terminal exposed side surface with respect to the upper surface of the holding member,
The length from the current sensor terminal exposed side surface to the tip of the current sensor terminal is shorter than the length from the signal terminal exposed side surface to the tip of the signal terminal. In the power converter device according to any one of claims 1 to 3 ,
A power converter, wherein the holding member and the control circuit board are each provided with a positioning opening for inserting a positioning pin of an assembly jig.

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