JP5682194B2 - Power converter - Google Patents

Description

  The present invention relates to a power converter including a series connection body in which switching elements are connected in series between a pair of connection lines, and a snubber capacitor connected in parallel to the series connection body.

  2. Description of the Related Art Conventionally, a series connection body in which switching elements such as insulated gate bipolar transistors (hereinafter simply referred to as IGBTs) are connected in series between a pair of connection lines has been provided, and between a power source and a load such as a rotating electrical machine (motor). There is known a power conversion device that is arranged in a converter and converts DC power into AC power.

  In such power conversion devices, in recent years, switching speed has been increased in order to shorten the switching excessive time. However, the connection line is formed by, for example, pressing a metal plate and has a self-inductance L. For this reason, as the switching speed increases, the surge voltage (ΔV = −L · di / dt) generated when the switching element is turned on or off increases, and the switching element may be destroyed.

  Therefore, recently, it is known that the above power converter includes a snubber capacitor that absorbs a surge voltage in the series connection body, and the switching element is prevented from being destroyed by the surge voltage. However, in a power converter equipped with a snubber capacitor, a surge voltage can be absorbed by arranging the snubber capacitor, but when the switching element is turned on or off, the snubber capacitor and the current path (connection line) resonate. As a result, the voltage between the terminals of the snubber capacitor oscillates, causing a new problem that distortion occurs in the output.

  In order to solve this problem, a power conversion device is disclosed in which plate-like induction conductors that generate an induction current are arranged in parallel and close to each other via an insulator with respect to a connection line (for example, a patent) Reference 1).

  In such a power converter, when an AC component flows through the connection line, a magnetic field is generated around the connection line due to the current. The magnetic field generates an induced electromotive force in the induction conductor disposed close to the connection line, and an induction current flows in the induction conductor in the opposite direction to the current flowing in the connection line. For this reason, a magnetic field in a direction opposite to the magnetic field formed around the connection line by the induced current is formed around the induction conductor, and the magnetic field formed around the connection line can be weakened. That is, the self-inductance of the entire current path through which the AC component flows can be reduced by the mutual inductance generated between the connection line and the induction conductor, thereby causing the snubber capacitor and the current path (connection line) to resonate. Can be suppressed.

JP 09-135565 A

  However, in such a power conversion device, in order to reduce the self-inductance, the induction conductor must be arranged in parallel and in close proximity to the connection line, and the arrangement is limited through an insulator. There is a problem.

  In view of the above, the present invention can suppress the resonance of the current path and the snubber capacitor when the switching element is turned on or off in the power conversion device using the connection line having self-inductance. An object of the present invention is to provide a power conversion device capable of improving the degree of freedom of arrangement.

In order to achieve the above object, the invention according to claim 1 includes a pair of connection lines (20, 30) through which a current flows, and a smoothing capacitor (40) between the pair of connection lines (20, 30). In a power converter having a series connection body in which switching elements (51, 52, 61, 62, 71, 72) are connected in series and a snubber capacitor (80) provided in the series connection body, a pair of connections The line (20, 30 ) has a self-inductance lower than that of the connection line and a resistance value between the connection point of the connection line and the smoothing capacitor (40) and the connection point of the connection line and the series connection body. High auxiliary wirings (21 to 23, 31 to 33) are provided, respectively , and the current paths configured to include the auxiliary wirings (21 to 23, 31 to 33) and the snubber capacitor (80). The self-inductance is made smaller than the self-inductance of the current path including the pair of connection lines (20, 30), and each of the auxiliary wirings (21 to 23) has the auxiliary wiring (21 to 23). It is a plane direction of the provided connection line, and is provided to protrude to the other connection line side different from one connection line provided with the auxiliary wiring of the pair of connection lines, and the auxiliary wiring (21 to 23, 31 to 31) 33), the area surrounded by the current path including the pair of connection lines (20, 30) is smaller than the area surrounded by the current path including the pair of connection lines (20, 30) .

  In such a power converter, at least one of the pair of connection lines (20, 30) has auxiliary wiring (21-23, 31-33) having a lower self-inductance and a higher resistance value than the connection line. Is provided. The self-inductance of the current path including the auxiliary wirings (21 to 23, 31 to 33) is made smaller than the self-inductance of the current path including the pair of connection lines (20, 30). Yes. For this reason, an alternating current component flows through the electric current path comprised including auxiliary wiring (21-23, 31-33). That is, the surge current when the switching element (51, 52, 61, 62, 71, 72) is turned on or off flows through a current path including the auxiliary wiring (21 to 23, 31 to 33). Therefore, the resonance of the current path and the snubber capacitor (80) can be suppressed as compared with the power converter that does not include the auxiliary wiring (21 to 23, 31 to 33).

  In addition, since the connection lines (20, 30) are provided with auxiliary wirings (21-23, 31-33), the auxiliary wirings (21-23) are compared with the conventional power conversion device including a plate-shaped induction conductor. 31 to 33) and the connection line need not be provided with an insulator. The self-inductance of the current path including the auxiliary wirings (21 to 23, 31 to 33) is made smaller than the self-inductance of the current path including the pair of connection lines (20, 30). Therefore, the auxiliary wirings (21 to 23, 31 to 33) need not be arranged in parallel to the connection lines, and the auxiliary wirings (21 to 23, 31 to 33) need not be arranged close to the connection lines. May be. Therefore, the degree of freedom in arrangement can be improved as compared with a conventional power conversion device including a plate-shaped induction conductor.

Further, as in the invention described in claim 2 , the rigidity of the auxiliary wirings (21-23, 31-33) can be made lower than the rigidity of the connection lines (20, 30).

Moreover, like invention of Claim 3 , auxiliary wiring (21-23, 31-33) can be provided through the hollow part of the cylindrical magnetic core (130) which has a hollow part.

Further, as in the invention described in claim 4 , the auxiliary wiring (21-23, 31-33) can be provided with a damping resistor. In such a power converter, by appropriately changing the resistance value of the damping resistor, the peak value of the voltage between the terminals of the snubber capacitor (80) and the attenuation characteristic when the current path and the snubber capacitor (80) resonate. Can be adjusted easily.

  In addition, the code | symbol in the bracket | parenthesis of each means described in this column and the claim shows the correspondence with the specific means as described in embodiment mentioned later.

It is a figure which shows a circuit structure when the control apparatus which controls a three-phase alternating current motor is comprised using the power converter device in 1st Embodiment of this invention. FIG. 2 is a schematic diagram showing a circuit configuration between a smoothing capacitor and a snubber capacitor provided in a U-phase arm in the control device shown in FIG. 1. It is a partial plane schematic diagram of the power converter device shown in FIG. (A) is a figure which shows the circuit structure which is not provided with auxiliary wiring, (b) is a figure which shows the voltage between the terminals of a snubber capacitor. (A) is a figure which shows the circuit structure provided with auxiliary wiring, (b) is a figure which shows the voltage between the terminals of a snubber capacitor. (A) is a figure which shows the voltage between the terminals of a snubber capacitor when the resistance value of a damping resistance is made into a critical braking value, (b) is when the resistance value of a damping resistance is made into about half of the critical braking value. It is a figure which shows the voltage between the terminals of a snubber capacitor. It is a partial plane schematic diagram of the power converter device in 2nd Embodiment of this invention. It is a figure which shows the circuit structure of FIG. It is a partial plane schematic diagram of the power converter device in 3rd Embodiment of this invention.

(First embodiment)
A first embodiment of the present invention will be described. FIG. 1 is a diagram illustrating a circuit configuration when a control device that controls a three-phase AC motor is configured using the power conversion device according to the present embodiment.

  As shown in FIG. 1, the power converter according to the present embodiment is connected to a high-potential-side power line 20 connected to the positive electrode of the power supply 10 and a negative electrode of the power supply 10, which corresponds to a pair of connection lines of the present invention. And a ground line 30 on the low potential side. In the present embodiment, the power supply line 20 and the ground line 30 are formed by pressing a metal plate, for example, having an inductance of 500 nH and a resistance value of 1 mΩ. Between the power supply line 20 and the ground line 30, a smoothing capacitor 40, a U-phase arm 50, a V-phase arm 60, and a W-phase arm 70 are provided in parallel.

  Smoothing capacitor 40 smoothes the main current supplied from power supply 10 and is provided between power supply 10 and U-phase arm 50. As the smoothing capacitor 40, for example, a 550 μF capacitor is used.

  Each of the U-phase arm 50, the V-phase arm 60, and the W-phase arm 70 includes high-potential side switching elements 51, 61, 71 connected to the power supply line 20 and a low-potential side switching element 52 connected to the ground line 30. , 62, 72 have a series connection body in which two switching elements 51, 52, 61, 62, 71, 72 are connected in series. Each switching element 51, 52, 61, 62, 71, 72 is provided with diodes 53, 54, 63, 64, 73, 74 connected in reverse parallel.

  Each of the U-phase arm 50, the V-phase arm 60, and the W-phase arm 70 is provided with a snubber capacitor 80. The snubber capacitor 80 absorbs a surge voltage generated when the switching elements 51, 52, 61, 62, 71, 72 are turned on or off, and for example, a 1 μF capacitor is used.

  Although the switching elements 51, 52, 61, 62, 71, 72 are not particularly limited, for example, an IGBT is used. The gates of the switching elements 51, 52, 61, 62, 71, 72 are connected to a control circuit (not shown), and the switching elements 51, 52, 61, 62, 71, 72 are controlled by a control signal from the control circuit. 72 is turned on or off.

  Further, the U-phase arm 50, the V-phase arm 60, and the W-phase arm 70 are respectively connected to a load 90 such as a rotating electric machine (motor) between two switching elements 51, 52, 61, 62, 71, 72. Connection wirings 55, 65, and 75 to be connected are connected.

  Further, the power supply line 20 is connected between the connection point of the smoothing capacitor 40 and the connection point of the U-phase arm 50, between the connection point of the smoothing capacitor 40 and the connection point of the V-phase arm 60, and the connection point of the smoothing capacitor 40. Auxiliary wirings 21 to 23 each having a lower self-inductance and a higher resistance value than that of the power supply line 20 are provided between the connection points of the W-phase arm 70 and the W-phase arm 70. Similarly, the ground line 30 is connected between the connection point of the smoothing capacitor 40 and the connection point of the U-phase arm 50, between the connection point of the smoothing capacitor 40 and the connection point of the V-phase arm 60, and connected to the smoothing capacitor 40. Auxiliary wirings 31 to 33 each having a lower self-inductance and a higher resistance value than ground line 30 are provided between the point and the connection point of W-phase arm 70. Each of the auxiliary wirings 21 to 23, 31 to 33 is, for example, a general one made of a flexible material with respect to a metal such as a vinyl wire or a wire, that is, one having rigidity lower than that of the connection lines 20 and 30. The one having a self-inductance of 100 nH and a resistance value of 10 mΩ is used.

  FIG. 2 is a schematic diagram showing a circuit configuration between the smoothing capacitor 40 and the snubber capacitor 80 provided in the U-phase arm 50 in the control device shown in FIG. In FIG. 2, the auxiliary wirings 22, 23, 32, and 33 are omitted.

  As shown in FIG. 2, the power supply line 20 and the ground line 30 are provided with auxiliary wirings 21 and 31 having lower self-inductance and higher resistance than the power supply line 20. Therefore, the direct current component mainly flows through a current path (path A in FIG. 2) having the power supply line 20 and the ground line 30, and the alternating current component is mainly a current path (path B in FIG. 2) having the auxiliary wirings 21 and 31. Flowing. The alternating current component flows in the opposite direction in the auxiliary wiring 21 and the auxiliary wiring 31.

  In the present embodiment, the auxiliary wirings 21 to 23 and 31 to 33 are provided in the power supply line 20 and the ground line 30 as follows. FIG. 3 is a partial schematic plan view of the power conversion device shown in FIG. 1, and corresponds to a two-dot chain line portion in FIG. In FIG. 3, the auxiliary wirings 22, 23, 32, and 33 are omitted.

  As shown in FIG. 3, in the power conversion apparatus, the power supply line 20 and the ground line 30 are arranged in parallel, and the power supply line 20 and the ground line 30 each include the semiconductor module 100 including the smoothing capacitor 40 and the switching element 51. , 52 are fixed to a semiconductor module 110 including a series connection body, diodes 53 and 54, and a snubber capacitor 80 connected in series by screws 120.

  The auxiliary wiring 21 provided in the power supply line 20 is provided in a planar direction of the power supply line 20 so as to protrude toward the ground line 30, and the auxiliary wiring 31 provided in the ground line 30 is provided in the planar direction of the ground line 30. In this case, the power supply line 20 is provided so as to protrude. A portion of the auxiliary wiring 21 that protrudes toward the ground line 30 and a portion of the auxiliary wiring 30 that protrudes toward the power supply line 20 are parallel to each other.

  That is, since the self-inductance of the entire current path is simply proportional to the area surrounded by the current path, the auxiliary wiring 21, the area surrounded by the current path including the power supply line 20 and the ground line 30, The area surrounded by the current path having 31 is made smaller. That is, even if the current path including the auxiliary wirings 21 and 31 is the same as the area surrounded by the current path including the power supply line 20 and the ground line 30, Since the self-inductance of 31 is smaller than that of the power supply line 20 and the ground line 30, the self-inductance of the entire current path is reduced. However, in the present embodiment, as described above, the self-inductance of the entire current path is further reduced by reducing the area surrounded by the current path including the auxiliary wirings 21 and 31.

  In other words, the self-inductance of the entire current path is reduced by arranging the auxiliary wirings 21 and 31 close to each other. For example, when the self-inductance L of the current path B in FIG. 2 is L1, the self-inductance of the auxiliary wiring 21 is L1, the self-inductance of the auxiliary wiring 31 is L2, and the mutual inductance of the auxiliary wirings 21, 31 is M, the auxiliary wiring 21, Since alternating current components in directions opposite to each other flow through 31, L = L1 + L2−M. For this reason, by arranging the auxiliary wirings 21 and 31 close to each other, the auxiliary wirings 21 and 31 are electromagnetically coupled to increase the mutual inductance, and the self-inductance of the entire current path is reduced.

  In the above description, the auxiliary wirings 21 and 31 in which the protruding portions are parallel have been described. However, for example, the auxiliary wiring 21 and the auxiliary wiring 31 may be twisted together. Moreover, the auxiliary wiring 21 and the auxiliary wiring 31 may be configured using, for example, vinyl parallel lines. Furthermore, in the above description, the portion between the smoothing capacitor 40 and the snubber capacitor 80 provided in the U-phase arm 50 has been described, but the other portions have the same configuration. That is, the auxiliary wirings 22 and 23 are provided so as to protrude toward the ground line 30 in the planar direction of the power line 20, and the auxiliary wirings 32 and 33 are disposed in the planar direction of the ground line 30 and on the power line 20 side. Is provided to protrude.

  As described above, in the power conversion device of the present embodiment, the auxiliary lines 21 to 23 and 31 to 33 having lower self-inductance and higher resistance values than the power supply line 20 are respectively provided in the power supply line 20 and the ground line 30. Is provided. The self-inductance of the current path including the auxiliary wirings 21 and 31 (for example, the current path B in FIG. 2) is the current path including the power line 20 and the ground line 30 (for example, FIG. 2 is smaller than the self-inductance of the current path A). For this reason, an alternating current component flows through the electric current path comprised including auxiliary wiring 21-23, 31-33. That is, the surge current when the switching elements 51, 52, 61, 62, 71, 72 are turned on or off flows through the current path including the auxiliary wirings 21-23, 31-33, and the auxiliary current Resonance between the current path and the snubber capacitor 80 can be suppressed as compared with a power converter that does not include the wirings 21 to 23 and 31 to 33.

  4 and 5 show the results of examining the voltage between the terminals of the snubber capacitor 80 by simulation using the lower arm drive half-bridge circuit, and FIG. 4A shows a circuit configuration having no auxiliary wiring. FIG. 4B is a diagram showing the voltage between the terminals of the snubber capacitor 80. FIG. 5A is a diagram showing a circuit configuration provided with auxiliary wiring, and FIG. 5B is a diagram showing a voltage between terminals of the snubber capacitor 80. 4 and 5 show simulation results when the voltage of the power supply 10 is 150 V and the current is 40A. 4 and 5, the inductance of the power supply line 20 and the ground line 30 is 500 nH, the resistance value is 1 mΩ, the capacitance of the smoothing capacitor 40 is 550 μF, and the capacitance of the snubber capacitor 80 is 1 μF. In FIG. 5, the auxiliary wirings 21 and 31 have an inductance of 100 nH and a resistance value of 10 mΩ. 4, the mutual inductance between the power supply line 20 and the ground line 30 is 10 nH, and in FIG. 5, the mutual inductance between the auxiliary wirings 21 and 31 is 100 nH.

  As shown in FIG. 4B, when the auxiliary wiring is not provided, when the switching element 52 is turned off at time T1, the snubber capacitor 80 and the current path resonate and the voltage between the terminals of the snubber capacitor 80 is increased. It is confirmed that the vibration does not converge even after 50 μs. On the other hand, as shown in FIG. 5B, when the auxiliary wirings 21 and 31 are provided, when the switching element 52 is turned off at the time T1, the snubber capacitor 80 and the current path resonate and the snubber is turned on. Although the voltage between the terminals of the capacitor 80 vibrates, it is confirmed that the peak value of the voltage can be reduced and the vibration can be almost converged after about 20 μs as compared with the case where the auxiliary wirings 21 and 31 are not provided. Is done.

  That is, in the power conversion device of the present embodiment, by providing the auxiliary wirings 21 and 31, it is possible to suppress resonance between the current path and the snubber capacitor 80. Note that the snubber capacitor 80 is disposed in the vicinity of the switching elements 51 and 52 and is sufficiently smaller than the capacity of the smoothing capacitor 40. Therefore, in the power converter, the snubber capacitor 80 and the current path are resonant. Will do. Further, in the above description, the voltage between the terminals of the snubber capacitor 80 when the switching element 52 is turned off has been described, but the behavior of the voltage between the terminals of the snubber capacitor 80 when the switching element 52 is turned on also has the same result. Become.

  In such a power converter, the auxiliary wirings 21 to 23 and 31 to 33 may be provided with damping resistors to adjust the resistance values. The resistance value of the damping resistor is not particularly limited, but is preferably selected as appropriate based on the critical braking value of the current path including the auxiliary wirings 21 to 23 and 31 to 33.

  FIG. 6 is a diagram showing the voltage between the terminals of the snubber capacitor 80 when a damping resistor is inserted into the circuit shown in FIG. 5A. FIG. 6A shows the resistance value of the damping resistor as a critical braking value. The figure which shows the voltage between the terminals of the snubber capacitor 80 at the time, (b) is a figure which shows the voltage between the terminals of the snubber capacitor 80 when the resistance value of the damping resistance is about half of the critical braking value.

  As shown in FIG. 6, when the turn-off is performed at time T1, the damping can be increased by inserting the damping resistor as compared with the voltage between the terminals of the snubber capacitor 80 where the damping resistor is not inserted. Can be confirmed. However, as shown in FIG. 6 (a), when the resistance value of the damping resistor is set to a critical braking value, it is possible to increase the attenuation of voltage oscillation compared to FIG. 5 (b). However, the voltage peak value becomes high. On the other hand, as shown in FIG. 6 (b), when the resistance value of the damping resistance is about half of the critical braking value, the attenuation of the voltage oscillation is reduced as compared with FIG. 5 (b). The peak value of the voltage can be reduced while increasing the voltage. For this reason, when a damping resistor is inserted, the resistance value of the damping resistor is preferably about half of the critical braking value.

  Moreover, in the said power converter device, the power supply line 20 and the ground line 30 should just be equipped with auxiliary wirings 21-23, 31-33, such as a vinyl wire and a wire, and auxiliary wiring 21-23, 31-33, and a power supply It is not necessary to provide an insulator between the line 20 and the ground line 30. Since the self-inductance of the current path configured including the auxiliary wirings 21 to 23 and 31 to 33 should be smaller than the self-inductance of the current path configured including the power supply line 20 and the ground line 30, The auxiliary wirings 21 to 23 and 31 to 33 need not be arranged in parallel to the power supply line 20 and the ground line 30, and the auxiliary wirings 21 to 23 and 31 to 33 are arranged close to the power supply line 20 and the grounding line 30. You don't have to. For this reason, the freedom degree of arrangement | positioning can be improved compared with the conventional power converter device provided with a plate-shaped induction | guidance | derivation conductor.

  In addition, compared with the conventional power converter that reduces the self-inductance of the current path by flowing an induced current through the induction conductor, the auxiliary wirings 21 to 23 and 31 to 33 are provided with a damping resistor, so that the voltage peak value and The attenuation can be easily adjusted.

  In the present embodiment, the auxiliary wirings 21 and 31, the auxiliary wirings 22 and 32, and the auxiliary wirings 23 and 33 are arranged close to each other so that the mutual inductance is increased. Self-inductance can be reduced.

(Second Embodiment)
A second embodiment of the present invention will be described. The power conversion device according to the present embodiment is configured by configuring the power supply line 20 with a braided wire with respect to the first embodiment, and the other aspects are the same as those of the first embodiment, and thus the description thereof is omitted here. . FIG. 7 is a partial schematic plan view of the power conversion device according to this embodiment, and corresponds to the two-dot chain line portion in FIG. 1. In FIG. 7, the auxiliary wirings 22 and 23 are omitted.

  As shown in FIG. 7, the power supply line 20 of the present embodiment is configured using a braided wire. The braided wire is provided with a core wire made of Al, Cu or the like covered with an insulator such as a resin, and an auxiliary wire 21 is knitted around the insulator, and an insulator such as a resin covering the auxiliary wire 21 is disposed. It is a thing. The auxiliary wiring 21 is extended from the vicinity of the portion connected to the semiconductor modules 100 and 110 and electrically connected to the ground line 30. For this reason, the area surrounded by the current path including the core wire 20a and the auxiliary wiring 21 can be made smaller than the area surrounded by the current path including the braided wire 20a and the ground line 30.

  FIG. 8 is a schematic diagram showing the circuit configuration of FIG. In FIG. 8, the auxiliary wirings 22 and 23 are omitted. As shown in FIG. 8, the AC component flows through the current path C in FIG. 8, flows through the core wire 20a on the power supply line 20 side, and flows through the auxiliary wiring 21 on the ground line 30 side. The same applies to the auxiliary wirings 22 and 23, and an AC component flows through the auxiliary wirings 22 and 23 on the ground line 30 side.

  In such a power converter, the power supply line 20 is configured using a braided wire, and a current path through which an AC component flows is configured using auxiliary wirings 21 to 23 arranged around the core wire 20a. For this reason, compared to the first embodiment, the current path in which the AC component flows in the opposite direction, that is, the core wire 20a and the auxiliary wires 21 to 23 can be further brought closer, and the mutual inductance can be increased. The self-inductance of the entire current path can be further reduced.

(Third embodiment)
A third embodiment of the present invention will be described. The power converter of this embodiment is provided with a magnetic core having a hollow portion through which the auxiliary wirings 21 to 23 and 31 to 33 are passed, compared to the first embodiment. Since it is the same as the embodiment, the description is omitted here. FIG. 9 is a partial schematic plan view of the power conversion device according to this embodiment, and corresponds to the two-dot chain line portion in FIG. 1. In FIG. 9, the auxiliary wirings 22, 23, 32, and 33 are omitted.

  As shown in FIG. 9, the power conversion device of this embodiment includes a cylindrical magnetic core 130 having a hollow portion, and the auxiliary wiring 21 is provided to pass through the hollow portion of the magnetic core 130. . Although not particularly limited, the magnetic core 130 is made of, for example, ferrite.

  Such a power converter includes a magnetic core 130, and a magnetic field is formed around the magnetic core 130. The auxiliary wirings 21 and 31 are provided through the hollow portion of the magnetic core 130. For this reason, compared with the case where the magnetic core 130 is not provided, when an alternating current component flows through the auxiliary wirings 21 and 31, the change in magnetic flux around the auxiliary wirings 21 and 31 can be reduced, and the self-inductance can be reduced. Can be small. For this reason, it can suppress that auxiliary wiring 21 and 31 and snubber capacitor 80 resonate further.

(Other embodiments)
In the first embodiment, the example in which the auxiliary lines 21 to 23 and 31 to 33 are provided in the power line 20 and the ground line 30 has been described. For example, the auxiliary lines 21 to 23 are provided only in the power line 20. Alternatively, auxiliary wirings 31 to 33 may be provided only on the ground line 30.

  In the first and third embodiments, the power supply line 20 is connected between the connection point of the smoothing capacitor 40 and the connection point of the U-phase arm 50, and the connection point of the smoothing capacitor 40 and the connection point of the V-phase arm 60. Between the connection point of the smoothing capacitor 40 and the connection point of the W-phase arm 70, auxiliary wirings 21 to 23 are provided, and the connection point of the smoothing capacitor 40 and the U-phase arm are provided on the ground line 30. 50 between the connection points of the smoothing capacitor 40 and the connection point of the V-phase arm 60, and between the connection point of the smoothing capacitor 40 and the connection point of the W-phase arm 70. Although the example provided with is described, for example, it can be as follows. That is, in the power supply line 20, between the connection point of the smoothing capacitor 40 and the connection point of the U-phase arm 50, between the connection point of the U-phase arm 50 and the connection point of the V-phase arm 60, Auxiliary wirings 21 to 23 can be provided between the connection point and the connection point of the W-phase arm 70, respectively. Similarly, in the ground line 30, between the connection point of the smoothing capacitor 40 and the connection point of the U-phase arm 50, between the connection point of the U-phase arm 50 and the connection point of the V-phase arm 60, the V-phase arm 60. Auxiliary wirings 31 to 33 can be provided between the connection point of W and the connection point of W-phase arm 70, respectively.

  Also in the second embodiment, between the connection point of the smoothing capacitor 40 and the connection point of the U-phase arm 50 in the power supply line 20, the connection point of the U-phase arm 50 and the connection point of the V-phase arm 60. Meanwhile, auxiliary wirings 21 to 23 can be provided between the connection point of the V-phase arm 60 and the connection point of the W-phase arm 70, respectively.

  Moreover, although each said embodiment demonstrated the example which applied the power converter device of this invention to the control apparatus which controls a three-phase alternating current motor, it is also applicable to the control apparatus which controls a single layer alternating current motor, for example. It is.

DESCRIPTION OF SYMBOLS 10 Power supply 20 Power supply line 21-23 Auxiliary wiring 30 Ground line 31-33 Auxiliary wiring 40 Smoothing capacitor 50 U-phase arm 60 V-phase arm 70 W-phase arm 80 Snubber capacitor 90 Load

Claims (4)

A pair of connection lines (20, 30) through which current flows are provided, and a smoothing capacitor (40) and switching elements (51, 52, 61, 62, 71, 72) are provided between the pair of connection lines (20, 30). ) In series connection, and a snubber capacitor (80) provided in the series connection,
In the pair of connection lines (20, 30 ), a connection point between the connection line and the smoothing capacitor (40) and a connection point between the connection line and the series connection body are more than the connection line. resistance with self-inductance is low is high auxiliary wiring (21 to 23 and 31 to 33) are provided, respectively,
The self-inductance of the current path including the auxiliary wiring (21 to 23, 31 to 33) and the snubber capacitor (80) is the current path including the pair of connection lines (20, 30). of which is smaller than the self-inductance,
Each of the auxiliary wirings (21 to 23) is a planar direction of a connection line provided with the auxiliary wiring (21 to 23), and is one connection line provided with the auxiliary wiring of the pair of connection lines. Projecting on the other connection line side different from
The area surrounded by the current path including the auxiliary wirings (21 to 23, 31 to 33) is smaller than the area surrounded by the current path including the pair of connection lines (20, 30). The power converter characterized by being made . The rigidity of the auxiliary line (21 to 23 and 31 to 33), the power converter according to claim 1, characterized in that it is lower than the rigidity of the connecting lines (20, 30). The auxiliary line (21 to 23 and 31 to 33) are claimed in claim 1 or 2, characterized in that provided through the hollow portion of the cylindrical magnetic core having a hollow portion (130) Power converter. The power converter according to any one of claims 1 to 3 , wherein the auxiliary wiring (21 to 23, 31 to 33) includes a damping resistor.

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