TWI695397B - Resistance device and inverter device - Google Patents

Abstract

An object of the present invention is to provide a resistor device which is compact and does not deteriorate the life of the capacitor. The resistance device of the present invention has: at least one resistor 61 connected in series to the smoothing capacitor 5a and the smoothing capacitor 5b connected in series; a resistor 62a connected in parallel to the smoothing capacitor 5a; a resistor 62b connected in parallel to the smoothing capacitor 5b; an insulating case 50 for sealing the resistors 61, 62a, 62b with a sealing material 56 filled therein.

Description

Resistance device and inverter device

The invention relates to a resistance device.

The conventional resistance device has an inrush current prevention resistance and a voltage balancing resistance. These two kinds of resistance systems are respectively fixed to the printed circuit board or the casing.

The inrush current prevention resistor is used to suppress the inrush current flowing into the capacitor when the input power is turned on. The inrush current prevention resistor is connected in parallel with the relay. When the relay is switched from OFF to ON after the capacitor is charged, the current flowing into the inrush current prevention resistor is diverted.

When multiple capacitors are connected in series to compensate for the insufficient withstand voltage of the capacitors, the voltage applied to each capacitor becomes unbalanced due to the uneven leakage current of each capacitor. In terms of prevention measures, a voltage balancing resistor is connected in parallel to each capacitor.

Patent Document 1 discloses a resistor device including a resistor for normal discharge and a resistor for rapid discharge having a resistance value smaller than that of the resistor for normal discharge. The resistance system for discharge is generally used as an inrush current prevention resistor, and the resistance system for rapid discharge is used as a voltage balancing resistor. [Prior Technical Literature] [Patent Literature]

[Patent Document 1] Japanese Patent Laid-Open No. 2014-36145

[Problem to be solved by invention]

In order to suppress the inrush current of the capacitor, the inrush current prevention resistor is required for pulse resistance. The larger the capacity of the capacitor, the larger the size of the inrush current prevention resistor. Therefore, although the inrush current prevention resistor is used only when the input power is turned on, there is a problem that it must be a large-sized resistor.

On the other hand, the voltage balancing resistor constantly generates heat to raise the ambient temperature of the capacitor, so there is a problem of deteriorating the life of the capacitor.

The present invention was developed in view of the above-mentioned problems, and aims to provide a small-sized resistance device that does not deteriorate the life of the capacitor. [Means to solve the problem]

The resistor device of the present invention includes: at least one first resistor body connected in series to the first smoothing capacitor and the second smoothing capacitor connected in series; a second resistor body connected in parallel to the first smoothing capacitor; and a third resistor The body is connected in parallel to the second smoothing capacitor; and the insulating case seals the first, second, and third resistors with a sealing material filled inside. [Effect of invention]

The resistance device according to the present invention is thermally combined by sealing the first, second, and third resistors in the insulating case. The timing of the temperature rise of the first resistor body and the second and third resistor systems is different, so when one of the temperature rises, the other resistor body can cool the heat. Therefore, the first, second, and third resistors can be miniaturized, and the resistance device can be miniaturized. Furthermore, when the second and third resistors are used as voltage balancing resistors, they constantly generate heat, but since they can dissipate heat to the first resistor, the deterioration of the life of the capacitor can be suppressed.

Embodiment 1. Fig. 1 is a circuit diagram of the inverter device 100 of the first embodiment. The inverter device 100 includes: three-phase (R-phase, S-phase, T-phase) input power pin, rectifier circuit 10, inrush current prevention resistor 4, inrush current prevention relay 3, relay drive circuit 2, smoothing capacitor 5a, 5b, voltage balancing resistors 6a, 6b and inverter 20.

The rectifier circuit 10 includes a plurality of rectifier diodes 1a, 1b, 1c, 1d, 1e, and 1f. The rectifier diodes 1a and 1d are connected to the R phase, the rectifier diodes 1b and 1e are connected to the S phase, and the rectifier diodes 1c and 1f are connected to the T phase. The smoothing capacitor 5a and the smoothing capacitor 5b are connected in series between the positive line Lp and the negative line Ln in order to ensure the withstand voltage. The inrush current preventing resistor 4 is a series connection body in which the smoothing capacitor 5a and the smoothing capacitor 5b are connected in series after the rectifier circuit 10. The inrush current prevention relay 3 is connected in parallel with the inrush current prevention resistor 4, and its ON/OFF is controlled by the relay drive circuit 2.

The inrush current prevention resistor 4 is used to limit the charging current flowing to the smoothing capacitors 5a, 5b. If there is no inrush current preventing resistor 4, when the input power pin is turned on, excessive inrush current will flow into the smoothing capacitors 5a, 5b that are not charged. When the smoothing capacitors 5a and 5b are charged, the inrush current prevention relay 3 is switched from OFF to ON by the relay drive circuit 2, and the current originally flowing to the inrush current prevention resistor 4 is inrushed from the inrush current prevention relay 3 The current prevents the resistor 4 from shunting. Therefore, the current does not flow through the inrush current preventing resistor 4.

The voltage division ratio of the smoothing capacitors 5a and 5b depends on the leakage current of the smoothing capacitors 5a and 5b. Due to the unevenness of the leakage current, the applied voltage of the smoothing capacitors 5a and 5b will also be uneven. In order to suppress the unevenness of the applied voltage, the smoothing capacitors 5a and 5b are connected in parallel with the voltage balancing resistors 6a and 6b, respectively. Simultaneously with the start of the charging of the smoothing capacitors 5a, 5b, voltage is applied to the voltage balancing resistors 6a, 6b, but the current value flowing to the voltage balancing resistors 6a, 6b is small, so the temperature of the voltage balancing resistors 6a, 6b is little by little. rise.

The inverter 20 includes an insulated gate bipolar transistor (IGBT) 7a, 7b, 7c, 7d, 7e, 7f, diode 8a, 8b, 8c, 8d, 8e, 8f, and a driving circuit 9a, 9b, 9c, 9d, 9e, 9f. In addition, an example of an IGBT-based power semiconductor element. The positive line Lp and the negative line Ln are respectively connected: a series circuit composed of U-phase switching IGBTs 7a, 7d, a V-phase switching IGBT 7b, 7e series circuit, and a W-phase switching IGBT 7c, 7f series circuit. The IGBTs 7a, 7b, 7c, 7d, 7e, and 7f are connected in antiparallel to the diodes 8a, 8b, 8c, 8d, 8e, and 8f, respectively. The junction of IGBT 7a and 7d is connected to the U-phase terminal U of the motor, the junction of IGBT 7b and 7e is connected to the V-phase terminal V of the motor, and the junction of IGBT 7c and 7f is connected to the W-phase terminal W of the motor . The gates and emitters of the IGBTs 7a, 7b, 7c, 7d, 7e, 7f individually receive the supply of drive signals from the drive circuits 9a, 9b, 9c, 9d, 9e, 9f, respectively. The drive circuits 9a, 9b, 9c, 9d, 9e, and 9f are equipped with optocouplers for optical insulation. They receive control signals from external control circuits such as microprocessors, generate drive signals, and connect IGBT7a, 7b, The gates and emitters of 7c, 7d, 7e, 7f provide driving signals.

FIG. 1 illustrates an inverter device 100 that converts the input power Pin of a three-phase (R-phase, S-phase, and T-phase) into a three-phase (U-phase, V-phase, and W-phase) power output Pout, but the present invention The system can also be applied to other various inverter devices or various converter devices. Furthermore, in FIG. 1, the inrush current prevention resistor 4 and the inrush current prevention relay 3 are arranged in the rear stage of the rectifier circuit 10, but they may also be arranged in the R phase and S of the input power pin before the rectifier circuit 10, respectively. Phase, T phase.

Referring to FIG. 2, the temperature change of the inrush current preventing resistor 4 and the voltage balancing resistors 6a and 6b will be described. In the second graph, curve 41 represents the temperature change of the inrush current preventing resistor 4, and curve 42 represents the temperature change of the voltage balancing resistors 6a and 6b. Furthermore, in the inverter device 100 of the first embodiment, the inrush current prevention resistor 4 and the voltage balancing resistors 6a and 6b are geothermally coupled as shown in FIGS. 5 and 6 and described below, but the second graph shows the inrush current The temperature change in the state where the resistance 4 and the voltage balancing resistors 6a and 6b are not thermally combined is shown, that is, the temperature change is assumed to be in a state where there is no thermal movement between the inrush current preventing resistor 4 and the voltage balancing resistors 6a and 6b.

First, the temperature change of the inrush current prevention resistor 4 shown in the curve 41 will be described. If the input power pin is turned on at time T=0, the temperature of the inrush current prevention resistor 4 will rise sharply. This is because the charging of the smoothing capacitors 5a, 5b starts, and the inrush current to the smoothing capacitors 5a, 5b is limited by the inrush current prevention resistor 4. As the smoothing capacitors 5a and 5b are charged, the current flowing to the inrush current preventing resistor 4 becomes small. If at time T=T1, the inrush current prevention relay 3 changes from OFF to ON, the current is shunted from the inrush current prevention resistor 4 by the inrush current prevention relay 3, so the temperature of the inrush current prevention resistor 4 Will come down. In this way, the inrush current preventing resistor 4 only circulates a large current for a short time when the smoothing capacitors 5a and 5b are charged, so a wire-wound resistor with high pulse resistance is used.

Next, the temperature changes of the voltage balancing resistors 6a and 6b shown in the curve 42 will be reviewed. When the input power pin is turned on at time T=0, charging of the smoothing capacitors 5a and 5b starts, and a voltage is simultaneously applied to the voltage balancing resistors 6a and 6b. However, the current value flowing to the voltage balancing resistors 6a and 6b is small, so the temperature of the voltage balancing resistors 6a and 6b rises little by little.

If the temperature changes of the inrush current prevention resistor 4 and the voltage balancing resistors 6a and 6b are compared, the timing of temperature rise of the two is different. When the temperature of the inrush current preventing resistor 4 becomes a peak (T=T1), the temperature of the voltage balancing resistors 6a and 6b does not increase significantly. Conversely, when the temperature of the voltage balancing resistors 6a and 6b is high, the inrush current prevents the temperature of the resistor 4 from exceeding a peak and decreasing.

FIG. 3 is a perspective view of the inverter device 100, and FIG. 4 is a side view of the inverter device 100 viewed in the direction of the arrow shown in FIG. In the inverter device 100, an inrush current prevention relay 3 (not shown), smoothing capacitors 5a, 5b, resistance device 30A, drive circuits 9a, 9b, 9c, 9d, 9e, 9f are mounted on the upper surface of the printed circuit board 33 (Not shown) and the relay drive circuit 2 (not shown), and the rectifier module 31 and the IGBT module 32 are mounted below. The rectifier module 31 and the IGBT module 32 are electrically connected to the printed circuit board 33 by soldering.

The rectifier module 31 is a module in which a plurality of diodes 1a, 1b, 1c, 1d, 1e, and 1f are packaged together in one package to form a rectifier circuit 10. The IGBT module 32 is a module that encapsulates IGBT 7a, 7b, 7c, 7d, 7e, 7f and diodes 8a, 8b, 8c, 8d, 8e, 8f together in one package. The rectifier module 31 and the IGBT module 32 are heat-generating electronic parts. Therefore, the rectifier module 31 and the IGBT module 32 are installed with a heat absorber 34, and the rectifier module 31 and the IGBT module 32 are cooled by the heat absorber 34.

Next, the structure of the resistance device 30A will be described. FIG. 5 is an exploded perspective view of the resistor device 30A, and FIG. 6 is an A-A cross-sectional view of the resistor device 30A of FIG. 5 in an assembled state. The resistor device 30A includes resistors 61, 62a, and 62b and an insulating case 50. The resistor 61 is used as the inrush current preventing resistor 4, and the resistors 62a and 62b are used as the voltage balancing resistors 6a and 6b.

The insulating case 50 has a rectangular parallelepiped shape, and recessed grooves 53, 54, 55 are formed from above. The resistor 61 is arranged in the groove 53, and the resistors 62a and 62b are arranged in the grooves 54 and 55, respectively. In other words, the groove 53 is the first groove of the resistor 61, the groove 54 is the second groove of the resistor 62a, and the groove 55 is the third groove of the resistor 62b. As a result, the positioning of the resistors 62a, 62b, and 62c in the insulating case 50 can be easily performed, and the uneven positions of the resistors 62a, 62b, and 62c can be suppressed. The resistors 61, 62a, and 62b are cylindrical. The electrode terminals 52c are connected to both ends of the resistor 61, the electrode terminals 52a are connected to both ends of the resistor 62a, and the electrode terminals 52b are connected to both ends of the resistor 63b.

In FIG. 5, the size of the inrush current preventing resistor 4 is set to be larger than the voltage balancing resistors 6a, 6b, and the groove 53 for configuring the inrush current preventing resistor 4 is set to be larger than that for configuring the voltage balancing resistors 6a, 6b之沟54,55. Thereby, the inrush current preventing resistor 4 can be prevented from being erroneously arranged in the grooves 54 and 55 for arranging the voltage balancing resistors 6a and 6b.

In the state where the resistors 61, 62a, 62b have been disposed in the grooves 53, 54, 55, the grooves 53, 54, 55 are filled with a sealing material 56 such as an adhesive. In this way, the resistors 61, 62a, and 62b are sealed in the insulating case 50 and thermally coupled. That is, the inrush current prevention resistor 4 and the voltage balancing resistors 6a and 6b are thermally coupled. As shown in FIG. 6, the sealing amount of the sealing material 56 is adjusted so that the sealing surface of the sealing material 56, that is, the upper surface of the sealing material 56 is lower than the upper surface of the insulating case 50. As a result, the creepage distance between the electrode terminals 52a, 52b, and 52c increases by the distance between the upper surface of the insulating case 50 and the sealing surface of the sealing material 56. Similarly, the leakage distance between the electrode terminals 52a, 52b, 52c and the case 40 in which the resistance device 30A is mounted also becomes longer.

The electrode terminals 52a, 52b, and 52c protrude upward from the insulating case 50, and the protruding portions thereof are connected to the printed circuit board 33 using connectors and wiring such as flat plate connectors (refer to FIG. 3). More specifically, the electrode terminal 52c is wired to connect the connection points 70c at both ends of the resistor 61 shown in the first figure. The electrode terminal 52a is wired to connect the connection points 70a at both ends of the resistor 62a shown in the first figure. The electrode terminal 52b is wired to connect the connection points 70b at both ends of the resistor 62b shown in the first figure. If the shape or size between the electrode terminal 52c and the electrode terminals 52a, 52b is changed, it is possible to prevent erroneous connection when the electrode terminals 52a, 52b, 52c are connected to the connection points 70a, 70b, 70c using a connector such as a flat connector.

In the resistance device 30A, a metal part 51 with a screw hole 57 is installed. The resistance device 30A is fixed by screwing the metal part 51 to the housing 40 with its bottom surface directly contacting the housing 40. Thereby, the heat generated by the resistance device 30A can be dissipated toward the housing 40 of the inverter device 100, so that the resistance device 30A can be miniaturized. In addition, the resistance device 30A can be installed on the side surface of the housing 40 or the heat absorber 34 in addition to the bottom surface of the housing 40, and the same effect can be obtained. In addition, the fixing method of the resistance device 30A is not limited to the above. The electrode terminals 52a, 52b, 52c may also be inserted into through holes provided in the printed circuit board 33 and soldered to the printed circuit board 33, thereby mounting the resistance device 30A on the printed circuit board 33.

As described above, the resistance device 30A of the first embodiment includes the resistor 61 as the first resistor connected in series to the smoothing capacitor 5a belonging to the first smoothing capacitor and the smoothing capacitor belonging to the second smoothing capacitor connected in series 5b; the resistor 62a, which is connected in parallel to the smoothing capacitor 5a as a second resistor; the resistor 62b, which is connected in parallel to the smoothing capacitor 5b as a third resistor; and the insulating case 50, which is filled in The sealing material 56 to seal the resistors 61, 62a, 62b. As a result, the inrush current prevention resistor 4 and the voltage balancing resistors 6a and 6b are thermally coupled. As shown in Figure 2, the timing of the temperature rise of the inrush current preventing resistor 4 and the voltage balancing resistors 6a, 6b is different. When the temperature of the inrush current preventing resistor 4 increases, the temperature of the voltage balancing resistors 6a, 6b does not rise. Therefore, the heat generated in the inrush current preventing resistor 4 moves to the voltage balancing resistors 6a and 6b, and the effect equivalent to the increase in the thermal capacity of the inrush current preventing resistor 4 is obtained, and the temperature rise of the inrush current preventing resistor 4 is suppressed. . When the temperature of the voltage balancing resistors 6a and 6b rises, the temperature of the inrush current preventing resistor 4 does not rise. Therefore, by moving the heat generated in the voltage balancing resistors 6a, 6b to the inrush current preventing resistor 4, an effect equivalent to the increase in the thermal capacity of the voltage balancing resistors 6a, 6b is obtained, and the temperature rise of the voltage balancing resistors 6a, 6b is suppressed . As a result, the inrush current prevention resistor 4 and the voltage balancing resistors 6a and 6b can be miniaturized. In addition, since the temperature increase of the voltage balancing resistors 6a and 6b can be suppressed, the increase in the ambient temperature of the smoothing capacitors 5a and 5b can be suppressed, and the deterioration of the life of the smoothing capacitors 5a and 5b can be suppressed.

Embodiment 2. Fig. 7 is an exploded perspective view of the resistor device 30B of the second embodiment. The resistance device 30B deforms a part of the resistance device 30A of the first embodiment. Therefore, the differences from the resistance device 30A of the first embodiment will be described below. As shown in FIG. 5, the resistance device 30A of the first embodiment arranges the resistors 62a and 62b as voltage balancing resistors 6a and 6b in different grooves 54 and 55 in the insulating case 50. In contrast, in the resistance device 30B of the second embodiment, the equipotential ends of the resistors 62a and 62b are connected by the common electrode terminal 52d, and the resistors 62a and 62b are arranged in the same groove 58. In other respects, the resistance device 30B is the same as the resistance device 30A of the first embodiment.

In the resistance device 30B of the second embodiment, one end of the resistor 62a and one end of the resistor 62b are connected by a common electrode terminal 52d, and the insulating case 50 includes a groove 53 in which the first groove of the resistor 61 is arranged, and an arrangement The groove 58 of the second groove of the resistors 62 and 63. The ends of the resistors 62a and 62b having the same potential are used as the common electrode terminal 52d, whereby the resistance device 30B can be miniaturized and the number of parts can be reduced. In addition, since the voltage balancing resistors 6a and 6b can be installed at a closer distance, the temperature difference between the voltage balancing resistors 6a and 6b is reduced due to heat. Therefore, the unevenness of the resistance values of the voltage balancing resistors 6a and 6b accompanying the temperature change of the resistors 62a and 62b can be reduced.

Embodiment 3. FIG. 8 is an exploded perspective view of the resistor device 30C of Embodiment 3, and FIG. 9 is a B-B cross-sectional view of the resistor device 30C of FIG. 8 in an assembled state. The difference between the configuration of the resistance device 30C and the resistance device 30B of the second embodiment will be described below. The configuration of the resistance device 30C, which is not specifically mentioned in the following description, is the same as the resistance device 30B of the second embodiment.

The resistance device 30B of the second embodiment is composed of one resistor 61 to constitute the inrush current preventing resistor 4, but the resistance device 30C is composed of two resistors 61 connected in series or in parallel to constitute the inrush current preventing resistor 4. In the resistor device 30B of the second embodiment, the resistor 61 constituting the inrush current preventing resistor 4 and the resistors 62a and 62b constituting the voltage balancing resistors 6a and 6b are arranged in different grooves 53 and 58. However, in the resistor device 30C, the resistors 61, 62a, and 62b are disposed in the same groove 59 provided in the insulating case 50. The groove 59 is a concave portion recessed from the upper surface of the insulating case 50.

The bottom surface of the groove 59 is provided with two protrusions 60 from one end to the other end. The groove 59 of the insulating case 50 is distinguished by the two protrusions 60 arranged in this way: a region sandwiched between the two protrusions 60, a region sandwiched between a protrusion 60 and the side surface of the groove 59, and a Three areas of the area between the other protrusion 60 and the side of the groove 59. In the region sandwiched between the two protrusions 60, resistors 62a and 62b are arranged, and in the remaining region, two resistors 61 are arranged with the resistors 62a and 62b in between. With the protrusion 60, the resistor 61 and the resistors 62a and 62b are not in contact, and positioning in the groove 59 of the resistors 61, 62a and 62b is performed.

In a state where the resistors 61, 62a, and 62b have been disposed in the groove 59, the groove 59 is filled with a sealing material 56 such as an adhesive. As shown in FIG. 9, the sealing amount of the sealing material 56 is adjusted so that the sealing surface of the sealing material 56, that is, the upper surface of the sealing material 56 is lower than the upper surface of the insulating case 50. In this way, the resistors 61, 62a, and 62b are sealed in the insulating case 50 and thermally coupled. That is, the inrush current prevention resistor 4 and the voltage balancing resistors 6a and 6b are thermally coupled.

The protrusion 60 is provided on the bottom surface of the groove 59 of the insulating case 50 and the resistors 61, 62a, 62b are positioned by the protrusion 60. Compared with Embodiments 1 and 2, the material of the insulating case 50 can be reduced and the manufacturing is easy. Furthermore, by arranging the resistor 61 constituting the inrush current preventing resistor 4 via the resistors 62a, 62b constituting the voltage balancing resistors 6a, 6b, the thermal properties of the inrush current preventing resistor 4 and the voltage balancing resistors 6a, 6b can be improved The combination makes it possible to improve the effect of cooling the heating of the resistors 62a, 62b with the resistor 61 and cooling the heating of the resistor 61 with the resistors 62a, 62b.

In this embodiment, the inrush current preventing resistor 4 is composed of a plurality of resistors 61, and the resistors 61 are arranged on both sides of the resistors 62a and 62b constituting the voltage balancing resistors 6a and 6b. However, it is also possible to configure the inrush current prevention resistor 4 with one resistor 61, a voltage balancing resistor 6a with a plurality of resistors 62a, and a voltage balancing resistor 6b with a plurality of resistors 62b, which are arranged via the resistor 61 Resistors 62a, 62b. However, compared to the resistor 61, the resistors 62a and 62b have a longer period of high temperature. Therefore, if the resistors 62a and 62b are disposed near the center of the insulating case 50, the uniform heating of the resistor device 30C is achieved.

In addition, the present invention can freely combine the embodiments within the scope of the invention, and the embodiments can be appropriately modified, modified, or omitted.

1a, 1b, 1c, 1d, 1e, 1f‧rectifier diode 2‧‧‧ Relay drive circuit 3‧‧‧Inrush current prevention relay 4‧‧‧Inrush current prevention resistor 5a, 5b ‧‧‧ smoothing capacitor 6a, 6b‧‧‧Voltage balance resistance 7a, 7b, 7c, 7d, 7e, 7f ‧‧‧ insulated gate bipolar transistor (IGBT) 8a, 8b, 8c, 8d, 8e, 8f ‧‧‧ diode 9a, 9b, 9c, 9d, 9e, 9f ‧‧‧ drive circuit 10‧‧‧Rectifier circuit 20‧‧‧Inverter 30A, 30B, 30C‧‧‧resistor device 31‧‧‧Rectifier module 32‧‧‧IGBT module 33‧‧‧ printed circuit board 34‧‧‧Heat absorber 40‧‧‧Housing 41, 42‧‧‧ curve 50‧‧‧Insulating shell 51‧‧‧Metal parts 52a, 52b, 52c, 52d ‧‧‧ electrode terminals 53, 54, 55, 58, 59 ‧‧‧ ditch 56‧‧‧Sealing material 57‧‧‧Screw hole 60‧‧‧protrusion 61, 62a, 62b ‧‧‧resistor 70a, 70b, 70c‧‧‧ connection point 100‧‧‧Inverter device Lp‧‧‧Main line Ln‧‧‧negative line Pin‧‧‧Input power (R phase, S phase, T phase) Pout‧‧‧Power output (U phase, V phase, W phase)

Fig. 1 is a circuit diagram of the inverter device of the first embodiment. Figure 2 is a graph showing the temperature change of the inrush current prevention resistance and the voltage balancing resistance. Fig. 3 is a perspective view of the inverter device of the first embodiment. Fig. 4 is a side view of the inverter device of the first embodiment. Fig. 5 is an exploded perspective view of the resistor device of the first embodiment. Fig. 6 is a cross-sectional view of the resistor device of the first embodiment. Fig. 7 is an exploded perspective view of the resistor device of the second embodiment. Fig. 8 is an exploded perspective view of the resistor device of the third embodiment. Fig. 9 is a cross-sectional view of the resistor device of the third embodiment.

30A‧‧‧Resistance device

50‧‧‧Insulating shell

51‧‧‧Metal parts

52b, 52c ‧‧‧ electrode terminal

56‧‧‧Sealing material

61, 62b‧‧‧resistor

Claims (9)

A resistance device with: At least one first resistor body connected in series to the first smoothing capacitor and the second smoothing capacitor connected in series; The second resistor is connected in parallel to the first smoothing capacitor; A third resistor connected in parallel to the aforementioned second smoothing capacitor; and The insulating case seals the first, second, and third resistors with a sealing material filled inside. The resistance device as described in item 1 of the patent application, wherein the first, second and third resistance systems are connected with electrode terminals, The electrode terminal protrudes from above the insulating case, The upper surface of the sealing material filled inside the insulating housing is lower than the upper surface of the insulating housing. The resistance device as described in item 1 or 2 of the patent application scope, wherein, The insulating housing is provided with at least one groove recessed from the upper surface of the insulating housing, The first, second and third resistance systems are arranged in the groove. The resistance device as described in item 3 of the patent application scope, in which The aforementioned groove system has: Configure the first groove of the aforementioned first resistor; Configuring the second groove of the aforementioned second resistor; and The third groove of the aforementioned third resistor body is arranged. The resistance device as described in item 3 of the patent application scope, in which One end of the second resistor body and one end of the third resistor body are connected by a common terminal, The aforementioned groove system has: Configuring the first trench of the aforementioned first resistor; and The second grooves of the second and third resistors are arranged. The resistance device as described in item 3 of the patent application scope, in which The first, second and third resistance systems are arranged in: a groove formed in the insulating housing; The insulating case has protrusions for positioning the first, second, and third resistors on the bottom surface of the groove. The resistance device as described in item 1 of the patent application scope, in which A plurality of the first resistance systems are arranged via the second and third resistors, and are connected in series or in parallel. The resistance device as described in item 1 of the patent application scope, in which The second and third resistance systems are arranged via the first resistor. An inverter device is provided with the resistance device as described in item 1 of the patent application scope.

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