JP4236909B2 - Power semiconductor module - Google Patents

Description

[0001]
BACKGROUND OF THE INVENTION
The present invention relates to a power semiconductor module incorporating a shunt resistor for detecting a current flowing in a power element attached to an insulating substrate on a heat sink.
[0002]
[Prior art]
In a conventional structure in which a shunt resistor for high power is mounted on an insulating substrate, a minute resistor is used to reduce the amount of heat radiation. To obtain such a minute resistor, the shunt resistor has a width of Wide shape. In order to detect a voltage drop from the shunt resistor, a connection point provided at one end of the shunt resistor and another connection point on the substrate pattern on which the shunt resistor is mounted are provided, and wires are drawn from both connection points. .
[0003]
There is one in which a slit is formed to adjust the resistance of the shunt resistor (see, for example, Patent Document 1).
[0004]
In order to increase the detection accuracy of the shunt resistor, there is one in which no current is supplied to the voltage detection terminal (see, for example, Patent Document 2).
[0005]
[Patent Document 1]
Japanese Patent Laid-Open No. 2000-174202, “Current Detection Resistor” (paragraph number [0008], FIG. 1)
[0006]
[Patent Document 2]
Japanese Patent Laid-Open No. 7-191059 “Current Detector” (paragraph number [0009], FIG. 1)
[0007]
[Problems to be solved by the invention]
By the way, the wide shunt resistor flows so as to be widely distributed on the pattern, and therefore flows between the two connection points, and a new voltage drop occurs between the two connection points. In addition, a switching current flows in the vicinity of the connection point, and an induced voltage is generated in the wire. As a result, the current from the (P) side power source to the (P) side power element (P side operation) and ( The detected voltage of the shunt resistor varies depending on the direction of the current from the N) side power element to the (N) side power supply (N side operation) (direction of current between PN). The imbalance of the shunt resistance output value caused the resistance value accuracy to deteriorate. The P-side operation and N-side operation will be described later with reference to the drawings.
[0008]
Although the thing of patent document 1 forms the slit which is the characteristics of this invention, it is for adjusting a shunt resistance value, and the thing of patent document 2 is not what formed the slit. It has a complicated structure.
[0009]
The present invention provides a power semiconductor module including a shunt resistor with high detection accuracy.
[0010]
The power semiconductor module according to the present invention, first, second power insulating substrate having a circuit pattern, a first switching that will be connected in reverse parallel to each other is mounted on the first circuit pattern on the front main surface A first semiconductor element group comprising a semiconductor element and a first freewheel diode; a first semiconductor element group mounted on the second circuit pattern and connected in antiparallel to each other and connected in series to the first switching semiconductor element; second switching semiconductor element and the second semiconductor element group composed of the second freewheel diode, before Symbol first flow Ru current to each of the switching semiconductor element and the second switching semiconductor elements from each other selectively and a shunt resistor for current detection that flows in opposite directions, one end connected to said first circuit pattern, the second circuit pattern Shunt resistor wire passing a current passing through the second switching semiconductor elements of the emissions is connected to the vicinity of the one end, and, power with two voltage detecting electrode portion for detecting a voltage generated in said main current in the semiconductor module, said first switching semiconductor element and the path of the current flowing to the shunt resistor through the first circuit pattern, the current flowing in the second switching semiconductor element through the second circuit pattern from from the shunt resistor at a position deviated from both paths of the path of, provided with the voltage detection electrode unit in the first circuit pattern, so that the current is not shunted to the voltage detecting electrode portion, before Symbol current and path, between the voltage detecting electrode portion, a slit to equalize the impedance between the detection positions regardless of the current direction of the current Formation to.
[0011]
DETAILED DESCRIPTION OF THE INVENTION
FIG. 9 shows an internal circuit diagram of a power semiconductor device to which the present invention is applied. Six power elements 12 formed in a three-phase bridge are housed in a package, and include DC power supply terminals BP and PN and AC output terminals U, V, and W. A shunt resistor 4 for current detection is provided on each line of the output terminal.
[0012]
Embodiment 1 FIG.
FIG. 1A shows Embodiment 1 of the present invention, which shows only one phase (for example, U phase) in the power semiconductor device of FIG. 9, and the other two phases (V, W). Phase) has the same configuration. A bottom surface 4 a (when attached) of the “U” -shaped shunt resistor 4 as viewed from the side in the figure is mounted on the pattern 2 formed on the insulating substrate 11. Current is supplied to the upper surface 4b of the shunt resistor 4 through the aluminum wire 5a (extracted at another timing), and current is extracted from the aluminum wire 5b through the pattern 2 to the lower surface 4a of the shunt resistor 4 (another timing). Supplied at timing).
[0013]
On the upper surface 4b of the shunt resistor 4, a voltage detection terminal Ta is provided on the left side of the connection portion of the aluminum wire 5a, and a voltage detection terminal Tb is provided on the pattern 2 on the left side of the terminal. The voltage drop detected by Ta and Tb is supplied to the external relay terminal 8 through the voltage detection wire 13. A semiconductor element and other power modules 12 are mounted on the pattern 2.
[0014]
Here, as a result of a part of the current flowing through the shunt resistor 4 also flowing in the vicinity of the terminal Tb on the pattern 2, as described above, a voltage drop occurs between both terminals Ta and Tb, and is unnecessary. An induced voltage was also generated.
[0015]
Therefore, in the first embodiment, a slit (pattern notch) 16a extending in the vertical direction in the figure is formed on the pattern 2 on the right side of the terminal Tb so that no current flows in the vicinity of the terminal Tb. . The slit 16 a is preferably separated from the current path of the shunt resistor as an “L” shape extending further to the right from the lower end of the slit so as to wrap around the lower left end of the shunt resistor 4.
[0016]
1B shows the flow of current between the PNs in the semiconductor device of FIG. 1A, and the bold arrow 19 indicates the flow from the P-side power supply (BP in FIG. 9) to the P-side power element. A thin arrow 20 indicates a flow (N-side operation) from the N-side power element to the N-side power source (BN in FIG. 9), which is another timing.
[0017]
As described above, even if the direction of the current is changed in the P-side operation and the N-side operation, the current flowing in the vicinity of both terminals Ta and Tb is reduced, so that the above-described problem does not occur, and therefore the output of the shunt resistor. The voltage value can be balanced. In addition, since the notch can be formed at the same time as the circuit pattern formation, it is possible to provide a small-sized power semiconductor module that is less expensive to manufacture than the one in which a slit is provided in the shunt resistor and the impedance between detection positions is equal. There is.
[0018]
Embodiment 2. FIG.
FIG. 2A shows a second embodiment of the present invention. In the structure in which the U-shaped shunt resistor 4 is mounted on the pattern 2, a voltage detection terminal Ta is provided on the upper surface of the shunt resistor 4 on the right side of the connection point of the aluminum wire 5a. The voltage detection terminal Tb is provided on the pattern 2 and on the right side of the connection point of the aluminum wire 5b. The voltage drop detected at both terminals Ta and Tb is supplied to the external relay terminal 8 through the voltage detection wire 13.
[0019]
And the slit 16b of the up-down direction is formed so that the terminal Tb may be separated from the connection location of the aluminum wire 5b. The slit 16b preferably has an "L" shape extending further to the right from the upper end of the slit so that the terminal Tb is also separated from the terminal Ta.
[0020]
FIG. 2B shows a current flow between PNs in the semiconductor device of FIG. 2A, and a bold arrow 19 indicates a flow from the P-side power source (BP in FIG. 9) to the P-side power element ( P-side operation), and a thin arrow 20 indicates a flow (N-side operation) from the N-side power element to the N-side power source (BN in FIG. 9), which is another timing.
[0021]
As described above, even if the direction of the current is changed in the P-side operation and the N-side operation, the current flowing in the vicinity of both terminals Ta and Tb is reduced, so that the above-described problem does not occur, and therefore the output of the shunt resistor. The voltage value can be balanced. In addition, since the notch can be formed at the same time as the circuit pattern formation, it is possible to provide a small-sized power semiconductor module that is less expensive to manufacture than the one in which a slit is provided in the shunt resistor and the impedance between detection positions is equal. There is.
[0022]
Embodiment 3 FIG.
FIG. 3A shows Embodiment 3 of the present invention. In the structure in which the U-shaped shunt resistor 4 is mounted on the pattern 2, a voltage detection terminal Ta is provided on the upper surface of the shunt resistor 4 at the upper right side of the connection point of the aluminum wire 5 a, and the lower side of the terminal The voltage detection terminal Tb is provided on the pattern 2 and on the upper right side of the connection portion of the aluminum wire 5b. The voltage drop detected at both terminals Ta and Tb is supplied to the external relay terminal 8 through the voltage detection wire 13.
[0023]
A horizontal slit 16c is formed so that the terminal Tb is separated from the connection point of the aluminum wire 5b. The slit 16c preferably has an “L” shape extending further upward from the left end of the slit.
[0024]
FIG. 3B shows the flow of current between the PNs in the semiconductor device of FIG. 3A, and the bold arrow 19 indicates the flow from the P-side power source (BP in FIG. 9) to the P-side power element ( P-side operation), and a thin arrow 20 indicates a flow (N-side operation) from the N-side power element to the N-side power source (BN in FIG. 9), which is another timing.
[0025]
As described above, even if the direction of the current is changed in the P-side operation and the N-side operation, the current flowing in the vicinity of both terminals Ta and Tb is reduced, so that the above-described problem does not occur, and therefore the output of the shunt resistor. The voltage value can be balanced. In addition, since the notch can be formed at the same time as the circuit pattern formation, it is possible to provide a small-sized power semiconductor module that is less expensive to manufacture than the one in which a slit is provided in the shunt resistor and the impedance between detection positions is equal. There is.
[0026]
Embodiment 4 FIG.
FIG. 4A shows Embodiment 4 of the present invention. In this embodiment, a gate-type shunt resistor 41 is mounted (as viewed from the side), and metal plates 41 b and 41 c are provided on both sides of the shunt resistor material 41 a located on the upper surface of the shunt resistor 41. Yes. Current is supplied to the upper end portion of the metal plate 41b through the aluminum wire 5a (drawn at another timing), and current is drawn from the aluminum wire 5b to the upper end portion of the other metal plate 41c through the pattern 2 (another time). Supplied at timing). Voltage detection terminals Ta and Tb are provided on the shunt resistor 41 on the left side of the connection points of the aluminum wires 5a and 5b. The voltage drop detected at both terminals Ta and Tb is externally transmitted through the aluminum wire 13. It is supplied to the relay terminal 8. The lower ends of the metal plates 41b and 41c are mounted on the insulating substrate 11 or the pattern 2 while being insulated from each other.
[0027]
A horizontal slit 16d is formed on the shunt resistor 41a of the shunt resistor 41 so as to separate both terminals Ta and Tb from each other. The slit in this case is a notch penetrating in the thickness direction of the shunt resistance material 41a.
[0028]
FIG. 4B shows the flow of current between the PNs in the semiconductor device of FIG. 4A, and the bold arrow 19 indicates the flow from the P-side power supply (BP in FIG. 9) to the P-side power element ( P-side operation), and a thin arrow 20 indicates a flow (N-side operation) from the N-side power element to the N-side power source (BN in FIG. 9), which is another timing. As described above, even if the direction of the current is changed in the P-side operation and the N-side operation, the current flowing in the vicinity of both terminals Ta and Tb is reduced, so that the above-described problem does not occur, and therefore the output of the shunt resistor. The voltage value can be balanced.
[0029]
Embodiment 5 FIG.
FIG. 5A shows Embodiment 5 of the present invention. The aluminum wires 5a and 5b are attached to the gate-type shunt resistor 41 in the same manner as in FIG. 4, but a voltage detection terminal is placed on the shunt resistor 41 on the right side of the connection point of the aluminum wires 5a and 5b. Ta and Tb are provided, and the voltage drop detected at both terminals Ta and Tb is supplied to the external relay terminal 8 through the aluminum wire 13. A horizontal slit 16e is formed in the shunt resistor material 41a of the shunt resistor 41 so as to separate both terminals Ta and Tb from each other.
[0030]
FIG. 5B shows the flow of current between the PNs in the semiconductor device of FIG. 5A, and the bold arrow 19 indicates the flow from the P-side power supply (BP in FIG. 9) to the P-side power element ( P-side operation), and a thin arrow 20 indicates a flow (N-side operation) from the N-side power element to the N-side power source (BN in FIG. 9), which is another timing. As described above, even if the direction of the current is changed in the P-side operation and the N-side operation, the current flowing in the vicinity of both terminals Ta and Tb is reduced, so that the above-described problem does not occur, and therefore the output of the shunt resistor. The voltage value can be balanced.
[0031]
Embodiment 6 FIG.
FIG. 6 (A) shows another embodiment of the gate-type shunt resistor 41 shown in FIG. 4 (A), and FIG. 6 (B) shows a front view thereof. The shunt resistor 50 includes a flat shunt resistor 50a and metal plates 50b and 50c attached to both sides thereof, and the above-described aluminum wires 5a and 5b are connected to the upper surfaces of the metal plates. And the slit 53 is formed in the end of the shunt resistance material 50a (The structure so far is the same as the shunt resistance 41 of FIG. 4 and FIG. 5). And the protrusion 54 of the same magnitude | size as the shape of the said slit 53 is formed in the other end of the shunt resistance material 50a.
[0032]
As shown in FIG. 6B, the metal plates 50b and 50c located on both sides of the shunt resistance member 50a are attached to the pattern 2 on the insulating substrate 11 by solder 73 in a state of being insulated from each other. Above the shunt resistor 50, a control board 100 including a control circuit for controlling the power element is provided via a predetermined support member 72.
[0033]
When such a shunt resistance material 41 is pressed from, for example, a strip-shaped material, the shunt resistance material 40a can be obtained by a single process, and no wasteful members are discarded.
[0034]
Embodiment 7 FIG.
As shown in FIG. 7, the gate-type shunt resistors 41 and 50 described above are fixed on the pattern 2 formed on the insulating substrate by the solder 61. As shown by the solder 61a, the metal plate 60b is used. , 60c, and reaches the surface of the shunt resistor 60a, the resistance value of the shunt resistor changes and the detection accuracy decreases.
[0035]
Therefore, in the shunt resistor 60 of the present embodiment, the coating treatment 62 for preventing the adhesion of solder is applied to the inner surfaces of the metal plates 60b and 60c and the shunt resistor material 60a. Variations in the resistance value can be prevented, and therefore the shunt resistor can be downsized in the height direction.
[0036]
Embodiment 8 FIG.
The shunt resistor 70 shown in FIG. 8 is provided on the pattern 2 in the same manner as in FIG. 7, but mounting pins 72 are attached to the upper end portions of the metal plates 70 b and 70 c by solder 73. The upper end is inserted into a through hole 100a formed in the control board 100, and the insertion portion is electrically connected to the pattern on the control board 100 by solder 74.
[0037]
In this embodiment, the voltage drop generated by the shunt resistor 70 can be taken out to the control board 100 side through the mounting pin 72, and the voltage detection wire 13 shown in FIG. In addition, the voltage detection path from the shunt resistor 70 to the control board 100 can be shortened. As a result, the inductance of the voltage detection value is reduced, it is not easily affected by other magnetic fields, is excellent in noise resistance, and the shunt resistance detection accuracy is improved. To do.
[0038]
【The invention's effect】
According to the present invention, since the means for equalizing the impedance between the detection positions is provided regardless of the current direction of the main current, the detection voltage value corresponding to the direction in which the main current flows can be reduced.
[Brief description of the drawings]
FIG. 1 is a plan view of a power semiconductor module to which a shunt resistor according to a first embodiment is attached. FIG. 2 is a plan view of a power semiconductor module to which a shunt resistor is attached according to a second embodiment. 3] A plan view of a power semiconductor module to which a shunt resistor according to the third embodiment is attached. [FIG. 4] FIG. 4 is a plan view of a power semiconductor module to which a shunt resistor according to the fourth embodiment is attached. FIG. 6 is a plan view of a power semiconductor module device mounted with a shunt resistor according to a fifth embodiment. FIG. 6 is a perspective view and a front view of a shunt resistor according to a sixth embodiment. FIG. 8 is a front view of a shunt resistor based on the eighth embodiment. FIG. 9 is an internal circuit diagram of a power semiconductor device to which the present invention is applied.
2 patterns, 4 shunt resistor, 4a shunt resistor material, 4b, 4c metal plate, 5 aluminum wire, 11 insulating substrate, 13 voltage detection wire, 16 slit, 41, 50, 60, 70 shunt resistor, 53 slit, 54 Protrusion, 62 Coating treatment, 72 Mounting pin, 100 Control board, Ta, Tb Voltage detection terminal

Claims (1)

A power insulating substrate having first and second circuit patterns on the front main surface;
The first semiconductor element group composed of the first is mounted on the circuit pattern and the first switching semiconductor elements that will be connected antiparallel to each other the first freewheel diode,
A second semiconductor device comprising a second switching semiconductor element mounted on the second circuit pattern and connected in antiparallel to each other and connected in series to the first switching semiconductor element, and a second freewheeling diode. Element group,
A front Symbol shunt resistor for current detection that flows through the first switching semiconductor element and the second respectively the flow Ru current from each other selectively and mutually opposite directions between the switching semiconductor element, one end of the first It is connected to the first circuit pattern, detecting a second voltage generated by the shunt resistor, and before Symbol current wires flowing the passing current switching semiconductor element is connected to the vicinity of the one end of the second circuit pattern In the power semiconductor module provided with two voltage detection electrode portions,
Said first from the switching semiconductor elements of the current flowing to the shunt resistor through the first circuit pattern path, the path of the current flowing in the second switching semiconductor element through the second circuit pattern from from the shunt resistor While providing the voltage detection electrode portion at a position deviated from both paths,
In the first circuit pattern, as before Symbol current is not shunted to the voltage detecting electrode portion, and the path before Symbol current, between the voltage detecting electrode portion, depending on the current direction of the current A power semiconductor module characterized in that a slit is formed to equalize the impedance between detection positions .

Images