JP2013198366A - Inverter device - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide an inverter device that suppresses leakage magnetic flux, induction noise, and radio wave noise more than before by dispersing a current distribution radially.SOLUTION: There is provided an inverter device 1 including a positive electrode 3P as a center electrode and a negative electrode 3N as an annular outer peripheral electrode, the electrodes being arranged concentrically inside and outside; and an upper arm and a lower arm of three phases including power semiconductor modules respectively, connected in series between the positive electrode 3P and negative electrode 3N, and also arranged annularly between the positive electrode 3P and negative electrode 3N. The inverter device 1 converts DC electric power into three-phase electric power, and outputs the electric power from respective legs between the upper arm and lower arm of the three phases. The respective phases are constituted with a plurality of parallel-connected upper arms (2U1H, 2U2H, 2V1H, 2V2H, 2W1H, and 2W2H) and a plurality of parallel-connected lower arms (2U1L, 2U2L, 2V1L, 2V2H, 2W1H, and 2W2H).

Description

  The present invention relates to an inverter device, and more particularly to an inverter device that suppresses leakage magnetic flux, induction noise, and radio noise.

  In recent years, hybrid vehicles equipped with an engine and a motor as a driving source for traveling are rapidly spreading, and various types of driving devices have been put into practical use. In many cases, a three-phase synchronous motor is used as the motor. The driving wheel is driven by power supplied from an on-vehicle battery power source during power running, and regenerative power generation is performed during braking to charge the battery power source. For this reason, it is common to provide an inverter device between the motor and the battery power source to perform bidirectional power conversion. Since a hybrid vehicle has a plurality of driving sources for traveling, the number of components tends to increase, and the mounting space is more restrictive than an engine vehicle. For this reason, a reduction in size and weight of the inverter device is strongly demanded.

  The applicant of the present application discloses an inverter device suitable for this kind of vehicle-mounted application in Patent Document 1. In the inverter device of Patent Document 1, a plurality of equilateral triangular power semiconductor chips are connected to constitute a power semiconductor module, and six power semiconductor modules are arranged in a regular hexagonal shape. In other words, in the conventional inverter device, the three-phase upper and lower arms are arranged in three rows, which is unbalanced. However, in Patent Document 1, the three phases are arranged rotationally symmetrically to improve the balance. Yes. Thereby, it is possible to suppress the occurrence of common mode noise caused by three-phase imbalance. Furthermore, since the inverter device has a ring shape (annular shape), it is suitable for integration with a motor having a substantially circular cross section.

JP 2009-88466 A

  By the way, in the inverter apparatus of patent document 1, a total of six power semiconductor modules of a three-phase upper arm and a lower arm are arrange | positioned rotationally symmetrically. However, the geometric direction in which the current flows, in other words, the arrangement of the current distribution is not rotationally symmetric. For example, considering the moment when the U phase terminal voltage of the motor is + E, the V phase terminal voltage is -E, and the W phase terminal voltage is zero, the motor current is supplied from the positive terminal of the DC power supply to the U phase upper arm and U phase of the inverter device. It returns to the negative terminal of the DC power supply via the leg, the U phase terminal, the V phase terminal of the motor, the V phase leg of the inverter device, and the V phase lower arm. At this moment, the motor current flows only in a total of two power semiconductor modules of the U-phase upper arm and the V-phase lower arm in the inverter device. Magnetic flux is induced by the motor current having this asymmetrical arrangement, and since it is asymmetrical, it is not canceled (does not cancel each other), and magnetic flux leaks to the outside to generate induction noise.

  In a similar manner, a high-frequency surge voltage and surge current are generated at the moment when the motor current is cut off by the power semiconductor module, and the surge current flows through a capacitor connected in parallel to the inverter device. Since this surge current is also asymmetrically arranged, a high-frequency magnetic flux change is radiated as radio noise. Inductive noise and radio wave noise may affect the control of electronic control devices arranged in the vicinity, and may cause a reduction in accuracy and malfunction of various sensors.

  The present invention has been made in view of the problems of the background art described above, and solves the problem of providing an inverter device in which current distribution is distributed radially to suppress leakage magnetic flux, induction noise, and radio wave noise more than in the past. It should be a challenge.

  The present invention aims to improve the performance of suppressing induction noise and radio wave noise without changing the size of the inverter device disclosed in Patent Document 1, and each phase is composed of a plurality of upper arms and lower arms, This is achieved by reducing the geometric composite vector.

  The invention of the inverter device according to claim 1 for solving the above-mentioned problems is a positive electrode connected to a positive electrode terminal of a DC power source, which is one of a central electrode and an annular outer peripheral electrode arranged concentrically inside and outside, and the central electrode A negative electrode connected to the negative electrode terminal of the DC power supply, the other of the outer peripheral electrodes, and a power semiconductor module for controlling the energization phase, and connected in series between the positive electrode and the negative electrode, and A three-phase upper arm and a lower arm that are annularly disposed between the positive electrode and the negative electrode, and converts DC power input from the DC power source into three-phase power, The inverter device outputs from each leg between the upper arm and the lower arm, and each phase is composed of a plurality of upper arms connected in parallel and a plurality of lower arms connected in parallel.

  According to a second aspect of the present invention, in the first aspect, the plurality of upper arms and the plurality of lower arms that are connected in parallel in each phase are arranged substantially rotationally symmetrically.

  According to a third aspect of the present invention, in the first or second aspect, the parallel number of the upper arm and the lower arm of each phase is either 2 parallels, 3 parallels, or 6 parallels.

  According to a fourth aspect of the present invention, in any one of the first to third aspects, the power semiconductor module is configured by using one or a plurality of equilateral triangular power semiconductor chips.

  According to a fifth aspect of the present invention, in any one of the first to fourth aspects, the plurality of upper arms and the plurality of lower arms connected in parallel each include a semiconductor rectifying element that rectifies AC power as the power semiconductor. It is provided in parallel with the module, and the three-phase power input to each leg can be converted into DC power and output.

  According to a sixth aspect of the present invention, in the fifth aspect, the power semiconductor module is configured by using one or a plurality of equilateral triangular power semiconductor chips, and the semiconductor rectifying element has the same shape and size as the power semiconductor chip. It is.

  The invention according to a seventh aspect is the invention according to any one of the first to sixth aspects, wherein the center electrode has an annular shape or a cylindrical shape having a hollow portion.

  In the invention of the inverter device according to claim 1, each phase is composed of a plurality of upper arms connected in parallel and a plurality of lower arms connected in parallel. Therefore, the geometric direction of the current flowing between the positive electrode and the negative electrode arranged inside and outside the concentricity is radially distributed by the plurality of upper and lower arms. Since at least a part of the magnetic flux induced by the dispersed currents is canceled (mutually canceled), the leakage magnetic flux and the induction noise are suppressed. Similarly, since the direction of the surge current generated at the moment when the current is cut off by the power semiconductor modules of the upper arm and the lower arm is also dispersed, some of the radio noise induced by the surge current is canceled (mutually canceled) E), radiation to the outside is suppressed. As a result, electromagnetic influences on electronic control devices and various sensors arranged in the vicinity are reduced.

  In the invention according to claim 2, the plurality of upper arms and the plurality of lower arms connected in parallel in each phase are respectively arranged substantially rotationally symmetrically. Accordingly, the combined vector obtained by geometrically adding the directional dispersed currents is substantially zero, and most of the induced magnetic flux is canceled, and the leakage magnetic flux and the induction noise are greatly suppressed. Similarly, most of the radio noise induced by the surge current is canceled, and the radiation to the outside is greatly suppressed.

  In the invention which concerns on Claim 3, the parallel number of the upper arm of each phase and a lower arm is made into either 2 parallel, 3 parallel, or 6 parallel. Therefore, the current is distributed in two paths, three paths, or six paths, and the absolute value of the current value becomes small and flows in a plurality of radial directions. For this reason, the greater the number of parallels, the smaller the combined vector becomes, and the induced noise and radio noise are reliably canceled and suppressed.

  In the invention according to claim 4, the power semiconductor module is configured by using one or a plurality of equilateral triangular power semiconductor chips. As is well known, since six equilateral triangles can be gathered at one point on the plane without overlapping, the shape of the equilateral triangle is very suitable for arranging the three-phase upper and lower arms in rotational symmetry. The present invention requires at least twelve power semiconductor modules, and by using a module composed of equilateral triangular power semiconductor chips, the upper arm and the lower arm can be arranged efficiently in space, and the inverter device can be miniaturized. .

  In the invention according to claim 5, a three-phase full-wave rectifier circuit is configured by providing a semiconductor rectifier element in each of a plurality of upper arms and lower arms connected in parallel, so that bidirectional power conversion can be performed.

  In the invention according to claim 6, the power semiconductor module is configured by using one or a plurality of equilateral triangular power semiconductor chips, and the semiconductor rectifying element has the same shape and size as the power semiconductor chip. Therefore, for the same reason as the fourth aspect, the inverter device can be miniaturized by arranging the upper arm and the lower arm in a space efficient manner.

  In the invention which concerns on Claim 7, the center electrode is made into the annular | circular shape or cylinder shape which has a hollow part. Therefore, a conductor for electrical connection can be passed through the hollow portion, or a rotating shaft for power transmission can be arranged, and the degree of freedom of installation position is great and user-friendliness is good.

It is a circuit diagram of the inverter apparatus of 1st Embodiment. It is the figure which showed the structure of the inverter apparatus of 1st Embodiment, (1) is side surface sectional drawing containing a central axis, (2) is the front view seen from the central axis direction. It is a figure which illustrates typically explaining the electric current which flows into an inverter apparatus, (1) is the geometric distribution of the electric current in 1st Embodiment, (2) is a synthetic vector figure at that time, (3) is in a prior art The geometric distribution of current, (4), shows the combined vector diagram at that time. It is a circuit diagram of the inverter apparatus of 2nd Embodiment. It is the front view seen from the central axis direction which shows two examples (1) and (2) of the structure of the inverter apparatus of 2nd Embodiment. It is a figure which illustrates typically explaining the electric current which flows into the inverter apparatus of 2nd Embodiment, (1) shows the geometric distribution of an electric current, (2) has each shown the synthetic | combination vector figure at that time. It is a circuit diagram of the inverter apparatus of 3rd Embodiment. It is the front view seen from the central axis direction which shows the structure of the inverter apparatus of 3rd Embodiment, (1) is a whole block diagram, (2) is the elements on larger scale for 60 degrees of central angles. It is a figure of the geometric distribution of the electric current which illustrates typically explaining the electric current which flows into the inverter apparatus of 3rd Embodiment. It is a circuit diagram of the inverter apparatus of a prior art. It is the front view seen from the central axis direction which shows the structure of the inverter apparatus of a prior art.

  The inverter apparatus 1 of 1st Embodiment of this invention is demonstrated with reference to FIGS. 1-3. FIG. 1 is a circuit diagram of an inverter device 1 according to the first embodiment. As illustrated, the inverter device 1 is used by being connected in parallel with the hollow cylindrical capacitor 8 with respect to the DC power source DC. In the inverter device 1, each of the three phases for performing power conversion by controlling the energization phase is composed of two upper arms connected in parallel and two lower arms connected in parallel (two-parallel configuration). . Therefore, a total of 12 arms are mounted in the entire apparatus 1. The U phase is taken as an example as a representative of the three phases and will be described in detail below.

  U-phase first upper arm 2U1H is configured by parallel connection of IGBT element 21H (insulated gate bipolar transistor element) corresponding to a power semiconductor module and rectifier diode 22H corresponding to a semiconductor rectifier element. The collector electrode CH of the IGBT element 21H is connected to the positive electrode 3P. The emitter electrode EH is connected to a U-phase output conductor 4U serving as a U-phase leg. The gate electrode GH is connected to a control unit (not shown) and receives a control signal. The anode AH of the rectifier diode 22H is connected to the U-phase output conductor 4U, and the cathode KH is connected to the positive electrode 3P.

  U-phase first lower arm 2U1L is also configured by parallel connection of IGBT element 21L and rectifier diode 22L. The collector electrode CL of the IGBT element 21L is connected to the U-phase output conductor 4U and the emitter electrode EH of the IGBT element 22H on the upper arm side. The emitter electrode EL is connected to the negative electrode 3N. The gate electrode GL is connected to a control unit (not shown) and receives a control signal. The anode AL of the rectifier diode 22L is connected to the negative electrode 3N, and the cathode KL is connected to the U-phase output conductor 4U.

  U-phase first upper arm 2U1H and U-phase first lower arm 2U1L are connected in series between positive electrode 3P and negative electrode 3N to constitute a U-phase first arm set. A U-phase second arm set including a U-phase second upper arm 2U2H and a U-phase second lower arm 2U2L having the same circuit configuration is connected in parallel to the U-phase first arm set. In the two arm sets, the positive electrode 3P, the negative electrode 3N, and the U-phase output conductor 4U are common.

  For the V phase and the W phase, the same circuit configuration as that of the U phase is used. That is, the V phase includes a V phase first upper arm 2V1H, a V phase first lower arm 2V1L, a V phase second upper arm 2V2H, and a V phase second lower arm 2V2L. The W phase includes a W phase first upper arm 2W1H, a W phase first lower arm 2W1L, a W phase second upper arm 2W2H, and a W phase second lower arm 2W2L.

  Next, the structure and geometric arrangement of the inverter device 1 will be described. 2A and 2B are diagrams illustrating the structure of the inverter device 1 according to the first embodiment, in which FIG. 2A is a side cross-sectional view including the central axis AX, and FIG. 2B is a front view viewed from the direction of the central axis AX. As shown in FIG. 2 (1), the inverter device 1 is integrally provided on the side surface of the hollow cylindrical capacitor 8 in the direction of the central axis AX. Further, as shown in (2) of FIG. 2, the inverter device 1 is annularly arranged between the positive electrode 3P and the negative electrode 3N.

  The hollow cylindrical capacitor 8 includes a one-pole connection portion 82, a second-pole connection portion 83, and a capacitance portion 84, and has a rotationally symmetric shape around the central axis AX. The one-pole connecting portion 82 includes a cylindrical inner peripheral cylindrical portion 821 and one side surface portion 822 extending outwardly from one end of the inner peripheral cylindrical portion 21. The other electrode connecting portion 83 includes a cylindrical outer peripheral cylindrical portion 831 and another side surface portion 832 extending in an inward flange shape from the other end of the outer peripheral cylindrical portion 831. An annular space is formed between the inner peripheral cylindrical portion 821, the one side surface portion 822, the outer peripheral cylindrical portion 831, and the other side surface portion 832. The electrostatic capacitance portion 84 is formed in a winding structure in which two electrode plates 85 and 86 and a thin film-like dielectric 87 are wound in a spiral shape inside the annular space. One of the two electrode plates 85 is connected to the one-pole connecting portion 82, and the other 86 is connected to the other-pole connecting portion 83. The internal structure of the hollow cylindrical capacitor 8 is not limited to the above, and may be a laminated structure, for example.

  The inverter device 1 is integrally provided in contact with the other side surface portion 832 of the other electrode connection portion 83 of the hollow cylindrical capacitor 8. As illustrated in (1) of FIG. 2, the IGBT elements 21H and 21L have a laminated structure, and the emitter electrodes EH and EL, the collector electrodes CH and CL, the insulator I1, and the output conductor 4U are sequentially arranged from the upper side in the drawing. 4V, the insulator I2, and the other side surface portion 832 of the other electrode connection portion 83 are stacked, and the gate electrodes GH and GL are not shown. In the upper arm side IGBT element 21 </ b> H illustrated on the right side in the drawing, the collector electrode CH and the one-pole connection portion 82 are connected by a connection lead 271. Further, in the IGBT element 21L on the lower arm illustrated on the left side in the drawing, the emitter electrode EL and the other electrode connection portion 83 are connected by the connection lead 272.

  As shown in (2) of FIG. 2, the arm set including the upper arm and the lower arm of the inverter device 1 is disposed between 60 degrees around the central axis AX. The two arm sets of each phase are arranged at a rotationally symmetric position of 180 ° with respect to the central axis AX. The six arm sets in total have the same shape and are arranged at a pitch of 60 ° around the central axis AX. The U-phase first arm set consisting of the U-phase first upper arm 2U1H and the U-phase first lower arm 2U1L is arranged within an angle θU1 (= 60 °) in the figure, A U-phase second arm set including a U-phase second upper arm 2U2H and a U-phase second lower arm 2U2L is disposed within an angle θU2 (= 60 °) in the drawing.

  The IGBT element 21H of the U-phase first upper arm 2U1H is configured as an isosceles trapezoid using three equilateral triangular power semiconductor chips. The rectifier diode 22H of the U-phase first upper arm 2U1H has the same shape and size as one equilateral triangular power semiconductor chip, and is (1/3) the size of the IGBT element 21H. And the rectifier diode 22H is arrange | positioned adjacent to the upper base of the short side of the isosceles trapezoid of IGBT element 21H, and the whole U-phase 1st upper arm 2U1H shape is an equilateral triangle. The collector electrode CH of the IGBT element 21 </ b> H is connected to the center-side one-pole connection portion 82 using the connection lead 271.

  On the other hand, the IGBT element 21L of the U-phase first lower arm 2U1L is also formed in an isosceles trapezoidal shape corresponding to three equilateral triangular power semiconductor chips, and the rectifier diode 22L is the same shape and size as one equilateral triangular power semiconductor chip. It is. And the rectifier diode 22L is arrange | positioned adjacent to the monopod of the isosceles trapezoid of IGBT element 21L, and the whole U-phase 1st lower arm 2U1L shape is a parallelogram. The emitter electrode EL of the IGBT element 21 </ b> L is connected to the other electrode connecting portion 83 on the outer peripheral side using the connection lead 272.

  In addition, the U-phase second upper arm set is disposed in a range of an angle θU2 (= 60 °) in the drawing which is a rotationally symmetric position of the U-phase first arm set. Furthermore, the V-phase first arm set is disposed in the range of an angle θV1 (= 60 °) rotated 60 ° clockwise from the U-phase first arm set, and 120 ° clockwise from the U-phase first arm set. The W-phase first arm set is arranged in the range of the rotated angle θW1 (= 60 °). The same applies to the second arm set side, the U-phase second arm set, the V-phase second arm set (range of angle θV2 (= 60 °)), and the W-phase second arm set (angle θW2 (= 60 °)). Are arranged at a 60 ° pitch in the clockwise direction.

  The positive electrode terminal of the DC power supply DC is connected to the one-pole connection portion 82 of the hollow cylindrical capacitor 8, and the negative electrode terminal of the DC power supply DC is connected to the other-pole connection portion 83. Therefore, the one-pole connecting portion 82 also serves as the positive electrode 3P that is the center electrode of the inverter device 1, and the other-pole connecting portion 83 also serves as the negative electrode 3N that is the outer peripheral electrode. Furthermore, in consideration of safety, the other electrode connecting portion 83 (= negative electrode 3N) on the outer peripheral side is used while being grounded. In addition, one end of the three-phase output conductors 4U, 4V, and 4W not shown in the figure is connected to the legs of each arm set, and the other end is connected to a three-phase load. For example, in the inverter device 1 mounted on a hybrid vehicle, an in-vehicle battery or a boost converter that boosts the battery voltage is connected as a DC power source DC, and a traveling motor is connected as a three-phase load. Thereby, a control signal can be input to the gate electrodes G of the IGBT elements 21H and 21L to control the driving of the traveling motor.

  The inverter device 1 can also be used when the traveling motor is used as a regeneration generator during braking of the hybrid vehicle. In this case, all IGBT elements 21H and 21L are turned off, and a total of twelve rectifier diodes 22H and 22L constitute a three-phase full-wave rectifier circuit. As a result, the three-phase power input to each leg can be converted into DC power and output to charge the battery.

  Next, the operation and effect of the inverter device 1 of the first embodiment will be described in comparison with the prior art exemplified in Patent Document 1. FIG. 10 is a circuit diagram of the prior art inverter device 9, and FIG. 11 is a front view showing the structure of the prior art inverter device 9 as viewed from the direction of the central axis AX.

  The inverter device 9 of the prior art has a general circuit configuration in which each of the three phases includes one upper arm and one lower arm. Each of the six IGBT elements 91H and 91L constituting the upper arm and the lower arm of each phase has a regular hexagonal shape in which six regular triangular power semiconductor chips are connected. Further, the upper arm and the lower arm of each phase are adjacent to each other around the central axis AX, and are arranged in order according to the phase order. Specifically, each of the IGBT elements 91H of the U-phase upper arm, the V-phase lower arm, the V-phase upper arm, the W-phase lower arm, the W-phase upper arm, and the U-phase lower arm at a 60 ° pitch in the clockwise direction in the figure. , 91L are arranged in order. These are connected to a positive electrode 3P which is a central electrode and a negative electrode 3N which is an outer peripheral electrode.

  Here, the geometrically synthesized vector of the currents flowing through the inverter device 1 of the first embodiment and the inverter device 9 of the prior art will be schematically described as an example. Assume that a positive voltage + E is generated at the U-phase terminal of the three-phase load, a negative voltage -E with an equivalent sign is generated at the V-phase terminal, the voltage at the W-phase terminal is zero, and the current I flows. This is shown in FIG. FIG. 3 is a diagram schematically illustrating the current I flowing through the inverter device. (1) is a geometric distribution of current in the first embodiment, (2) is a combined vector diagram at that time, and (3) ) Is a geometric distribution of current in the prior art, and (4) is a combined vector diagram at that time. The combined vector used here is not a current vector considering a general phase relationship but based on a geometric path through which a current flows. The amount of magnetic flux leakage can be estimated from the combined vector diagram.

  As shown in (1) of FIG. 3, in the first embodiment, the current I is supplied from the positive electrode 3P to the U-phase first current IU1 of the U-phase first upper arm 2U1H and the U-phase second upper arm 2U2H. After being shunted to the U-phase second current IU2, it flows into the U-phase terminal of the three-phase load. Accordingly, the U-phase first current IU1 and the U-phase second current IU2 flow in a geometrically opposite direction. Similarly, after the current I is shunted from the V-phase terminal of the three-phase load to the V-phase first current IV1 of the V-phase first lower arm 2V1L and the V-phase second current IV2 of the V-phase second lower arm 2V2L, Reflux to the negative electrode 3N. Therefore, the V-phase first current IV1 and the V-phase second current IV2 also flow in a geometrically opposite direction. For this reason, the combined vector of the current I in the inverter device 1 of the first embodiment is canceled and approaches zero as shown in (2) of FIG. Furthermore, if the symmetry inside and outside the inverter device 1 is well maintained, the current I is divided into two equal parts and the combined vector becomes zero.

  Since the above-described current canceling action occurs due to the shunting in each phase, it always occurs for any three-phase current other than that illustrated in FIG. In an extreme case, the current canceling action occurs even when the vector sum considering the phase of the three-phase current does not become zero due to a ground fault.

  On the other hand, in the prior art, the current I flows from the positive electrode 3P via the U-phase upper arm to the U-phase terminal of the three-phase load without being shunted. Further, the current I flows back from the V-phase terminal of the three-phase load to the negative electrode 3N through the V-phase lower arm without being shunted. Therefore, U-phase upper arm current IU and V-phase lower arm current IV are equal to current I flowing through the three-phase load. Therefore, when the combined vector of the current I is obtained in the inverter device 9 of the prior art, the vector sum Isum remains without being canceled as shown in (4) of FIG.

  That is, in the prior art, a leakage magnetic flux caused by the vector sum Isum is generated, whereas in the first embodiment, the combined vector is small and the leakage magnetic flux is greatly suppressed. Therefore, the induction noise caused by the leakage magnetic flux is greatly suppressed, and the emission of radio noise induced by the surge current is greatly suppressed. As a result, electromagnetic influences on electronic control devices and various sensors arranged in the vicinity are reduced.

  Moreover, since the inverter apparatus 1 of 1st Embodiment is provided with the rectifier diodes 22H and 22L and can comprise a three-phase full-wave rectifier circuit, it can perform electric power conversion to bidirectional | two-way. For example, in the in-vehicle inverter device 1, the battery can be charged by regenerative power generation. At this time, the direction in which the current flows is opposite to (1) and (2) in FIG. 3, but the action of canceling the current and reducing the combined vector occurs in the same way, so that the induced noise during regenerative power generation occurs. In addition, radio noise is also suppressed.

  Further, the IGBT elements 21H and 21L are composed of three equilateral triangular power semiconductor chips, and the rectifier diodes 22H and 22L elements have the same shape and size as the power semiconductor chips. Therefore, the upper arm and the lower arm can be arranged efficiently in space, and the inverter device 1 can be downsized. In addition, the positive electrode 3P has a cylindrical shape, and a conductor for electrical connection can be passed through the hollow portion or a rotating shaft for power transmission can be disposed. Therefore, the degree of freedom in installation position is great and the usability is good. Further, since the negative electrode 3N arranged on the outer periphery is grounded, the positive electrode 3P on the center side where the ground voltage is generated can be shielded, and the safety is high.

  Next, the inverter device 1A according to the second embodiment will be described mainly with respect to differences from the first embodiment with reference to FIGS. FIG. 4 is a circuit diagram of the inverter device 1A of the second embodiment. As shown in the figure, the inverter device 1A of the second embodiment is configured by three upper arms and three lower arms connected in parallel in each of the three phases. Then, a total of 18 arms are mounted (3 parallel configuration). The U phase is taken as an example as a representative of the three phases and will be described in detail below.

  U-phase first to third upper arms 5U1H, 5U2H, and 5U3H are configured by parallel connection of IGBT element 51H and rectifier diode 52H. Similarly, U-phase first to third lower arms 5U1L, 5U2L, and 5U3L are also configured by parallel connection of an IGBT element 51L and a rectifier diode 52L. U-phase output conductors 4U1 to 4U3 connected to the middle leg of the three arm sets are provided in each arm set. The circuit configurations of the V phase and the W phase are the same as the U phase, and redundant description is omitted.

  Next, the structure and geometric arrangement of the inverter device 1A according to the second embodiment will be described. FIG. 5 is a front view of two examples (1) and (2) of the structure of the inverter device 1A according to the second embodiment viewed from the direction of the central axis AX. In the example of (1), the annular positive electrode 3P is disposed on the central axis AX. In the example of (2), a further reduction in size and weight is achieved by arranging the positive electrode on the extension line (back side of the drawing) of the central axis AX.

  In (1) and (2) of FIG. 5, the IGBT elements 51H and 51L are formed in a rhombus shape using two equilateral triangular power semiconductor chips. The rectifier diodes 52H and 52L have the same shape and size as one equilateral triangular power semiconductor chip, and are half the size of the IGBT elements 51H and 51L. The IGBT elements 51H and 51L and the rectifier diodes 52H and 52L constituting each arm are disposed adjacent to each other. The output conductor of each arm set is also arranged in the vicinity. 5 (1) and (2) show a total of 18 diamond-shaped IGBT elements 51H and 51L, a total of 18 equilateral triangular rectifier diodes 52H and 52L, and a total of 9 square output conductors. ing.

  FIG. 5A shows three U-phase arm sets, that is, three upper arms 5U1H, 5U2H, 5U3H, three lower arms 5U1L, 5U2L, 5U3L, and three output conductors 4U1 to 4U3. The code | symbol is attached | subjected to. As shown in the figure, the three arm sets are arranged rotationally symmetrically at a 120 ° pitch. Further, reference numerals are assigned to the V-phase first upper arm 5V1H, the V-phase first lower arm 5V1L, and the output conductor 4V1, and a total of three identical configurations are arranged in a rotationally symmetrical manner at a 120 ° pitch. The same applies to the W-phase, and the W-phase first upper arm 5W1H, the W-phase first lower arm 5W1L, and the output conductor 4W1 are labeled, and a total of three identical configurations are arranged rotationally symmetrical at a 120 ° pitch. Has been.

  (2) in FIG. 5 is an aspect in which the arrangement of the arm and the output conductor is different from that in (1). Still, the same is true in that a total of three sets of each phase are arranged rotationally symmetrical at a pitch of 120 °.

  Next, the operation and effect of the inverter device 1A of the second embodiment will be described by taking as an example the case where the same current I flows as in the first embodiment. The following description is common to the structures (1) and (2) in FIG. FIG. 6 is a diagram schematically illustrating the current I flowing through the inverter device 1A of the second embodiment. (1) is a geometric distribution of current, and (2) is a combined vector diagram at that time. Show.

  As shown in FIG. 6 (1), in the second embodiment, the current I is divided from the positive electrode 3P to the three U-phase upper arms 5U1H, 5U2H, and 5U3 and then the U-phase terminal of the three-phase load. Flow into. Therefore, the diverted U-phase currents IU21, IU22, and IU23 flow geometrically at 120 ° from each other and are distributed radially. Similarly, the current I is shunted from the V-phase terminal of the three-phase load to the three lower arms of the V-phase, and then flows back to the negative electrode 3N. Accordingly, the shunted V-phase currents IV21, IV22, IV23 also geometrically form 120 ° from each other and are distributed radially. For this reason, the combined vector of the current I in the inverter device 1A of the second embodiment is canceled and approaches zero as shown in (2) of FIG. Further, if the symmetry inside and outside the inverter device 1A is kept well, the current I is divided into three equal parts and the combined vector becomes zero.

  According to the inverter device 1A of the second embodiment, the absolute values of the individual currents divided as compared with the first embodiment are reduced to approximately (2/3), and the flowing geometric direction is 3 from 2 directions. Increase in the direction. For this reason, the combined vector is reliably reduced, and the induction noise and radio wave noise are reliably canceled and suppressed.

  Next, with respect to the inverter device 1B of the third embodiment, differences from the first embodiment will be mainly described with reference to FIGS. FIG. 7 is a circuit diagram of the inverter device 1B of the third embodiment. As shown in the figure, the inverter device 1B of the third embodiment is composed of six upper arms connected in parallel to each of the three phases and six lower arms connected in parallel. 36 arms are mounted (6-parallel configuration). In 3rd Embodiment, the structure of each upper arm and each lower arm is the same as 1st and 2nd embodiment, and only parallel numbers differ. As shown in FIG. 7, the U phase includes U phase first to sixth upper arms 61H to 66H and U phase first to sixth lower arms 61L to 66L. The same applies to the V phase and the W phase, and the reference numerals are omitted.

  Next, the structure and geometric arrangement of the inverter device 1B according to the third embodiment will be described. FIG. 8 is a front view showing the structure of the inverter device 1B of the third embodiment viewed from the direction of the central axis AX, where (1) is an overall configuration diagram, and (2) is a partially enlarged view corresponding to a central angle of 60 °. is there. As shown in (1) of FIG. 8, the inverter device 1B is annularly arranged between the positive electrode 3P and the negative electrode 3N. FIG. 8 (1) shows a total of 36 equilateral triangular IGBT elements, a total of 36 equilateral triangular rectifier diodes, and a total of 18 square output conductors.

  As shown in (2) of FIG. 8, one set of three-phase arm sets is arranged in a range of a central angle of 60 °. Symbols Q1 to Q3 in the figure are U-phase, V-phase, and W-phase upper-arm IGBT elements, and symbols Q4-Q6 are U-phase, V-phase, and W-phase lower-arm IGBT elements. The IGBT elements of the same phase are arranged adjacent to each other on one side of an equilateral triangle (Q1 and Q4, Q2 and Q5, Q3 and Q6). In the figure, reference numerals D1 to D3 are rectifier diodes on the upper arm side of the U phase, V phase, and W phase, and reference signs D4 to D6 are rectifier diodes on the lower arm side of the U phase, V phase, and W phase. . The rectifier diode is not necessarily adjacent to the IGBT elements connected in parallel. In addition, three-phase output conductors 4U, 4V, and 4W are disposed at positions near the negative electrode 3N on the outer peripheral side.

  Six sets of the above-described range of the central angle in the range of 60 ° are arranged in the circumferential direction to form the entire configuration of the inverter device 1B. Accordingly, the six arm sets of each phase are arranged rotationally symmetrically at a 60 ° pitch.

  Next, the operation and effect of the inverter device 1B of the third embodiment will be described by taking as an example the case where the same current I flows as in the first embodiment. FIG. 9 is a diagram of a geometric distribution of the current I that schematically illustrates and explains the current I flowing through the inverter device 1B of the third embodiment. In the third embodiment, the current I is branched from the positive electrode 3P to the six U-phase upper arms 61H to 66H, and then flows into the U-phase terminal of the three-phase load. Therefore, as shown in the drawing, the divided U-phase currents IU31 to IU36 flow in a geometrically distributed manner at 60 ° from each other. Similarly, the current I is shunted from the V-phase terminal of the three-phase load to the six V-phase lower arms, and then flows back to the negative electrode 3N. Accordingly, the shunted V-phase currents IV31 to IV36 also flow in a geometrically distributed manner at 60 ° from each other. For this reason, the combined vector of the current I in the inverter device 1B of the third embodiment is canceled and approaches zero, as shown in the figure. Furthermore, if the symmetry inside and outside inverter device 1B is well maintained, current I is divided into six equal parts and the combined vector becomes zero.

  According to the inverter device 1B of the third embodiment, the absolute values of the individual currents divided as compared with the first embodiment are reduced to approximately (1/3), and the flowing direction is increased from 2 directions to 6 directions. . For this reason, the combined vector is further reliably reduced, and the induction noise and radio wave noise are more reliably canceled and suppressed.

  In the first to third embodiments, the number of IGBT elements 21H, 21L, 51H, 51L, and Q1 to Q6 increases, but the required current capacity is small, so that the element shape is reduced. Can be small. Therefore, the sizes of the inverter devices 1, 1A, 1B are not significantly changed from the conventional configuration. The detailed internal structure and electrical characteristics of the regular hexagonal, isosceles trapezoidal, rhomboid, and equilateral triangular IGBT elements 91H, 91L, 21H, 21L, 51H, 51L, Q1 to Q6 are described in the related art. Reference is made to US Pat.

  The inverter apparatus of each embodiment is suitable for the drive control part of the driving motor of a hybrid vehicle, and can also be used for other uses. The present invention can have various other applications and modifications.

1, 1A, 1B: Inverter device 2U1H: U-phase first upper arm 2U1L: U-phase first lower arm 2U2H: U-phase second upper arm 2U2L: U-phase second lower arm 2V1H: V-phase first upper arm 2V1L: V-phase first lower arm 2V2H: V-phase second upper arm 2V2L: V-phase second lower arm 2W1H: W-phase first upper arm 2W1L: W-phase first lower arm 2W2H: W-phase second upper arm 2W2L: W-phase Second lower arm 21H, 21L, 51H, 51L: IGBT element (power semiconductor module)
CH, CL: Collector electrode EH, EL: Emitter electrode
GH, GL: Gate electrodes 22H, 22L, 52H, 52L: Rectifier diode (semiconductor rectifier)
AH, AL: Anode KH, KL: Cathode 3P: Positive electrode 3N: Negative electrode 41U, 41U1, 41U2: U phase output conductor 41V, 41V1, 41V2: V phase output conductor 41W, 41W1, 41W2: W phase output conductor 5U1H, 5U2H, 5U3H: U-phase first to third upper arms 5U1L, 5U2L, 5U3L: U-phase first to third lower arms 5V1H: V-phase first upper arm 5V1L: V-phase first lower arm 5W1H: W-phase first Upper arm 5W1L: W-phase first lower arm 61H to 66H: U-phase first to sixth upper arms 61L to 66L: U-phase first to sixth lower arms 8: Hollow cylindrical capacitor
82: One pole connection part 83: The other pole connection part 84: Capacitance part
85, 86: Electrode plate 87: Dielectric 9: Prior art inverter device 91H, 91L: IGBT elements Q1-Q6: IGBT elements D1-D6: Rectifier diodes IU1: U-phase first current IU2: U-phase second current IV1 : V-phase first current IV2: V-phase second current IU21 to IU23: Divided U-phase current IV21 to IV23: Divided V-phase current IU31 to IU36: Divided U-phase current IV31 to IV36: Divided V-phase current X : Center axis DC: DC power supply

Claims (7)

A positive electrode connected to the positive electrode terminal of the DC power supply, which is one of the center electrode and the annular outer peripheral electrode arranged inside and outside the concentricity, and a negative electrode terminal of the DC power supply which is the other of the center electrode and the outer peripheral electrode. A connected negative electrode;
A three-phase upper arm and a lower arm, each of which includes a power semiconductor module for controlling a current-carrying phase and is connected in series between the positive electrode and the negative electrode and arranged in a ring shape between the positive electrode and the negative electrode With arm,
An inverter device that converts DC power input from the DC power source into three-phase power and outputs it from each leg between the upper and lower arms of the three-phase,
An inverter device in which each phase is constituted by a plurality of upper arms connected in parallel and a plurality of lower arms connected in parallel.   The inverter device according to claim 1, wherein the plurality of upper arms and the plurality of lower arms connected in parallel in each phase are arranged substantially rotationally symmetrically.   3. The inverter device according to claim 1, wherein the parallel number of the upper arm and the lower arm of each phase is either 2 parallels, 3 parallels, or 6 parallels.   The inverter device according to claim 1, wherein the power semiconductor module is configured by using one or more equilateral triangular power semiconductor chips.   5. The plurality of upper arms and the plurality of lower arms connected in parallel each have a semiconductor rectifier element that rectifies AC power in parallel with the power semiconductor module according to claim 1. An inverter device that enables the three-phase power input to each leg to be converted into DC power.   6. The inverter device according to claim 5, wherein the power semiconductor module is configured by using one or a plurality of equilateral triangular power semiconductor chips, and the semiconductor rectifying element has the same shape and size as the power semiconductor chip.   The inverter device according to claim 1, wherein the center electrode has an annular shape or a cylindrical shape having a hollow portion.

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