JP2023084360A - Power source device and power source device testing method - Google Patents

Abstract

To provide a power source device and a power source device testing method in which cost is not increased.SOLUTION: A power source device 1 includes: a power source unit 10 that outputs power to a power source line 13 formed of a positive electrode 13P and a negative electrode 13N; and a casing 30 that houses the power source unit 10 and is a ground potential. The power source unit 10 includes: Y capacitors 14B and 14C that are disposed between the positive and negative electrodes and the casing; a connection terminal 40 that is connected to the Y capacitors 14B and 14C and is disposed with a non-conductive gap provided relative to the casing 30; and conduction means 44 that is attachable/detachable to/from the outside of the casing 30 and provides electrical conduction between the casing 30 and the connection terminal 40 while being mounted on the casing 30 and connecting to the gap.SELECTED DRAWING: Figure 1

Description

The present invention relates to a power supply device that supplies electric power and a test method for the power supply device.

2. Description of the Related Art As a noise countermeasure for a power supply device that supplies power to a load, it is widely practiced to provide a Y capacitor in the power supply line. When a dielectric strength test is performed on such a power supply device, the test result may not be normal due to current flowing from the power supply line to the ground potential of the housing or the like via the Y capacitor.

Patent Literature 1 discloses a configuration in which a switching relay and a positive temperature coefficient thermistor are provided between the Y capacitor and ground to suppress the current flowing through the Y capacitor.

JP 2020-156139

In the conventional technology described above, since the current flows through the Y capacitor via the thermistor, it is necessary to select the Y capacitor in consideration of the withstand voltage of the Y capacitor in preparation for the test, which increases the cost. In addition, there is also the problem of increased cost due to an increase in the number of components such as thermistors and relays.

SUMMARY OF THE INVENTION It is an object of the present invention to provide a power supply device and a test method for the power supply device that do not increase the cost.

According to one embodiment of the present invention, it is applied to a power supply that supplies power to a load. A power supply device includes a power supply unit that outputs power to a power supply line composed of a positive electrode and a negative electrode, and a housing that accommodates the power supply unit and has a ground potential. The power supply unit includes a set of Y capacitors interposed between the positive and negative electrodes and the housing, and connection terminals connected to the Y capacitors and arranged with a non-conducting gap with respect to the housing. and a conducting means which is detachable from the outside of the housing and which connects the gap while attached to the housing to electrically connect the housing and the connection terminal.

According to the present invention, the connection terminal arranged between the Y capacitor and the housing is insulated from the ground potential by having the gap, and in the state of being conductive to the ground potential by fixing the conducting means. It is possible to switch between With such a configuration, the connection terminal can be insulated from the ground potential when performing a dielectric strength test, for example, and the Y capacitor can be connected to the ground potential after the test. There is no need to increase the resistance of the capacitor, and an increase in cost can be suppressed.

FIG. 1 is an explanatory diagram of a power supply device according to an embodiment of the present invention. FIG. 2 is an explanatory diagram showing a withstand voltage test of a power supply device. FIG. 3 is a perspective view of the power supply device. FIG. 4 is an exploded perspective view when the power supply device is observed from the bottom side. FIG. 5 is a cross-sectional view of the power supply device. FIG. 6A is an explanatory diagram of a connection terminal. FIG. 6B is an explanatory diagram of a connection terminal. FIG. 6C is an explanatory diagram of a connection terminal. FIG. 7 is a flow chart of a withstand voltage test. FIG. 8 is an explanatory diagram of a power supply device according to a modification of the present invention.

BEST MODE FOR CARRYING OUT THE INVENTION Hereinafter, embodiments of the present invention will be described with reference to the drawings.

FIG. 1 is an explanatory diagram of a power supply device 1 according to an embodiment of the present invention.

The power supply device 1 includes a power supply section 10 , a load 20 and a housing 30 .

The power supply unit 10 is composed of a power supply circuit 11 and a filter circuit 14 .

The power supply circuit 11 includes a battery 12 and a power supply line 13 having a positive electrode 13P and a negative electrode 13N. The power supply circuit 11 outputs DC power supplied from the battery 12 to the load 20 via the power supply line 13 .

The filter circuit 14 reduces normal mode noise and common mode noise contained in the direct current output from the power supply circuit 11 to the load 20 .

The filter circuit 14 includes an X capacitor 14A arranged between the positive electrode 13P and the negative electrode 13N, and Y capacitors 14B and 14C respectively arranged between the positive electrode 13P and the negative electrode 13N and the housing 30. .

X capacitor 14A reduces normal mode noise superimposed between positive electrode 13P and negative electrode 13N of power supply line 13 .

The Y capacitor 14B has a positive electrode connected to the positive electrode 13P and a ground electrode connected to the connection terminal 40, and the Y capacitor 14C has a positive electrode connected to the negative electrode 13N and a ground electrode connected to the connection terminal 40. . As will be described in detail later, the connection terminal 40 has the same potential as the housing 30 when connected to the housing 30, that is, the ground potential. Y capacitor 14B and Y capacitor 14C reduce common mode noise of power supply line 13 with respect to the ground potential.

These X capacitor 14A, Y capacitor 14B and Y capacitor 14C are housed in the housing 30 as an integrally molded capacitor module 14M.

The load 20 includes a motor 2 and an inverter circuit 21 that supplies electric power to the motor 2 .

The inverter circuit 21 converts the DC current supplied from the power supply circuit 11 into AC power and outputs the AC power to the motor 2 . Also, the inverter circuit 21 converts the regenerated power of the motor 2 into a DC current and outputs the DC current to the power supply circuit 11 .

The inverter circuit 21 includes switching elements 21u1 and 21u2 corresponding to the U phase of the motor 2, switching elements 21v1 and 21v2 corresponding to the V phase, and switching elements 21w1 and 21W2 corresponding to the W phase. .

The inverter circuit 21 is accommodated in the housing 30 as an inverter module 21M in which these switching elements are integrally molded.

In this embodiment, the load 20 is configured by the inverter circuit 21 and the motor 2, but the configuration is not limited to this. Any load can be used as long as it is supplied with a direct current from the power supply circuit 11 .

The housing 30 accommodates the power supply section 10 and the load 20 . The housing 30 becomes a reference potential (earth potential) with respect to the power supply section 10 and the load 20 .

In this embodiment, as will be described later with reference to FIG. 3, a configuration in which the filter circuit 14 and the inverter circuit 21 of the power supply unit 10 are housed in the housing 30 will be described as an example. That is, the power supply circuit 11 is configured such that DC power is supplied from a battery provided outside the housing 30 to the power supply line 13 inside the housing 30 via cables, connectors, and the like. Also, the power output from the inverter circuit 21 is configured to be supplied to the motor 2 arranged outside the housing 30 via a cable, a connector, or the like.

Note that such a configuration is not necessarily required, and the battery 12 may be arranged inside the housing 30, and the inverter circuit 21 (that is, the load) may be arranged outside the housing 30. There may be.

Next, the withstand voltage test will be explained.

FIG. 2 is an explanatory diagram of a dielectric strength test.

A dielectric strength test is a test to measure whether an electrical device has sufficient insulation from the ground potential. As shown in FIG. 2, the dielectric strength test is performed by short-circuiting the positive and negative sides of the power supply line 13, connecting the probes of the test apparatus 100 to the power supply line 13 and the ground potential, respectively, and supplying an alternating current (for example, 50 Hz, 2000 V) is applied for a predetermined time (for example, 60 seconds), the electrical characteristics are measured by detecting the current flowing during that time, and the dielectric strength test is evaluated based on the measurement results.

Here, a case where the connection terminal 40 described in this embodiment is connected to the housing 30 (ground potential) like a conventional general power supply device during a withstand voltage test will be described with reference to FIG. In this case, the ground-side electrode of the Y capacitor is electrically connected to the ground potential of the housing, so that the current applied from the test equipment during testing is transferred from the power supply line to the Y capacitor as indicated by the dotted line in FIG. It flows through a capacitor to ground potential. This current may be several hundred mA depending on the capacity of the Y capacitor, and the test result may be diagnosed as defective by detecting this with the test equipment.

Also, the Y capacitor generally has its withstand voltage (eg, 600 V) set based on the voltage of the power supply circuit 11 (eg, 450 V). Therefore, if a current of several thousand volts is applied during testing, there is a possibility that the withstand voltage of the Y capacitor will be exceeded and the Y capacitor will fail. In order to prevent this, the withstand voltage of the Y capacitor can be set high, but in this case the size and cost of the Y capacitor increase.

Therefore, in this embodiment, as described in FIG. 1, the connection terminal 40 is arranged with a non-conducting gap with respect to the housing 30 so as not to be affected by the Y capacitors 14B and 14C during the withstand voltage test. configured to

3 to 5 are explanatory diagrams of the power supply circuit 11 of this embodiment. 3 is a perspective view of the power supply circuit 11, FIG. 4 is an exploded perspective view of the power supply circuit 11 viewed from the bottom side, and FIG. 5 is a cross-sectional view taken along line VV in FIG.

As shown in FIGS. 3 and 4, the housing 30 is composed of a box-shaped body portion 32 whose bottom side is open, and a bottom portion 33 configured to close the open portion of the body portion 32 on the bottom side. be. The bottom portion 33 and the main body portion 32 have a plurality of fixing holes 31 on their outer edges, and are fixed by fastening fixing members (for example, bolts) to the fixing holes 31 . The body portion 32 and the bottom portion 33 are made of a conductive metal material such as an aluminum alloy.

A cooling water inlet 35 that introduces cooling water into a cooling water flow path 38 inside the housing 30 and a cooling water outlet 36 that discharges cooling water from the cooling water flow path 38 protrude from the bottom surface of the housing 30 . be. The bottom portion 33 is formed with notches 35A and 36A so as to avoid the cooling water inlet 35 and the cooling water outlet 36, respectively.

As shown in FIG. 4, the body portion 32 of the housing 30 accommodates a resin plate 37, a capacitor module 14M, an inverter module 21M, and the like. Capacitor module 14M and inverter module 21M are fixed on resin plate 37 and housed in main body 32 . A cooling water flow path 38 is formed inside the resin plate 37, and the cooling water cools the capacitor module 14M and the inverter module 21M.

A connection terminal 40 is erected on the bottom side of the capacitor module 14M.

As shown in the cross-sectional view of FIG. 5, one end of connection terminal 40 is fixed to bus bar 140 extending from capacitor module 14M. The bus bar 140 is connected to the ground electrodes of the Y capacitors 14B and 14C inside the capacitor module 14M. The other end of the connection terminal 40 on the bottom side is arranged with a non-conducting gap (for example, 1 mm) with respect to the bottom 33 . As shown in FIG. 4, the connection terminal 40 is arranged at the outer edge of the housing 30, for example, at a location adjacent to the fixing hole 31 for fixing the main body portion 32 and the bottom portion 33. As shown in FIG.

An insulator 200 is sandwiched between the connection terminal 40 and the bottom portion 33 . The insulator 200 has a flexible tape-like shape. The insulator 200 is made of an electrically insulating sheet-like material such as Kapton tape (“Kapton” is a registered trademark of DuPont) or motor insulating paper. By sandwiching the insulator 200 in the gap between the connection terminal 40 and the bottom portion 33 in this way, the degree of insulation between the connection terminal 40 and the bottom portion 33 is enhanced. Also in the withstand voltage test, if the connection terminal 40 and the bottom portion 33 have a sufficient degree of insulation, the insulator 200 does not necessarily have to be placed inside the housing 30 .

The insulator 200 is sandwiched between the connection terminal 40 and the bottom portion 33 , and one end of the insulator 200 extends to the outside of the housing 30 through the gap between the notch portion 36A of the bottom portion 33 and the cooling water outlet 36 . is extended to A slight gap is provided between the cutout portion 36A (or cutout portion 35A) of the bottom portion 33 and the cooling water outlet 36 (or cooling water inlet 35) even when the bottom portion 33 is fixed to the main body portion 32. It is Therefore, using this gap, the insulator 200 can be extended to the outside of the housing 30 without providing a new structure.

Since the insulator 200 extends to the outside of the housing 30 in this manner, the connection terminal 40 and the bottom portion 33 can be separated from each other by pulling out the insulator 200 after the withstand voltage test is completed, as will be described later. The insulator 200 can be easily removed from the gap.

A hole portion 33A is formed through the bottom portion 33 at a position where the connection terminal 40 is positioned when the bottom portion 33 is fixed to the main body portion 32 .

A screw hole 41 is formed in the connection terminal 40 . The connection terminal 40 is configured such that the fastening bolt 44 can be fastened to the connection terminal 40 by inserting the fastening bolt 44 from the outside of the bottom portion 33 through the hole portion 33A in a state where the bottom portion 33 is fixed to the main body portion 32 . there is

FIGS. 6A, 6B, and 6C are explanatory diagrams when changing from an insulated state to a conductive state between the connection terminal 40 and the bottom portion 33 of the housing 30. FIG.

In the assembled state of the power supply device 1, the insulator 200 is sandwiched between the connection terminal 40 and the bottom portion 33, as shown in FIG. 6A. The insulator 200 extends to the outside of the housing 30 from the gap between the cutout portion 36A of the bottom portion 33 and the cooling water outlet 36 . No fastening bolt 44 is connected to the connection terminal 40 . In this state, the connection terminals 40, that is, the ground sides of the Y capacitors 14B and 14C are insulated from the housing 30, that is, the ground potential. A dielectric strength test is performed in this state.

After the dielectric strength test is completed, the insulator 200 is first pulled out of the housing 30 as shown in FIG. 6B in order to connect the connection terminal 40 to the ground potential.

Next, as shown in FIG. 6C , the fastening bolt 44 is inserted from the outside of the bottom portion 33 through the hole 33A, and the fastening bolt 44 is fastened to the screw hole 41 of the connection terminal 40 .

When the fastening bolt 44 is fastened to the screw hole 41 , the bottom portion 33 and the fastening bolt 44 , and the fastening bolt 44 and the connection terminal 40 come into contact with each other. As a result, the connection terminal 40 is electrically connected to the bottom portion 33 , so that the ground-side electrodes of the Y capacitors 14 B and 14 C are brought to the ground potential through the connection terminal 40 . With such a configuration, the fastening bolt 44 is configured as a conducting means.

Thus, the connection terminal 40 provided on the ground side of the Y capacitors 14B and 14C is configured to be detachable from the ground potential by the fastening bolt 44 detachably configured from the outside of the housing 30 .

Using this fact, the fastening bolt 44 is removed when the dielectric strength test is performed, and after the dielectric strength test is completed, the fastening bolt 44 is tightened to connect the ground side electrodes of the Y capacitors 14B and 14C to the ground potential. be able to.

FIG. 7 is a flow chart showing the test method of the dielectric strength test of this embodiment.

In step S<b>10 , the operator attaches the test device 100 to the power supply circuit 11 . More specifically, the positive electrode 13P and the negative electrode 13N of the power supply line 13 of the power supply circuit 11 are short-circuited, and the probe on the positive electrode side of the test apparatus 100 is connected to this. At the same time, the probe on the negative electrode side of the test apparatus 100 is connected to the housing 30 of the power supply circuit 11 .

At this time, the connection terminal 40 is insulated from the ground potential as shown in FIG. 6A.

In step S20, the testing apparatus 100 executes a test procedure for a dielectric strength test. An alternating current (50 Hz, 2000 V) is applied by the test apparatus 100 for 60 seconds. The test apparatus 100 measures the electrical characteristics between the power supply line 13 and the housing 30 during this period, and evaluates the dielectric strength test based on the measurement results (step S30).

After the dielectric strength test is completed, in step S40, the probe of the test apparatus 100 is removed from the power supply circuit 11, and the short circuit between the positive electrode 13P and the negative electrode 13N of the power supply line 13 is restored.

Next, in step S50, the insulator 200 is removed from the gap between the connection terminal 40 and the bottom portion 33, as shown in FIG. 6B. The insulator 200 is removed from the gap between the connection terminal 40 and the bottom portion 33 by holding the portion of the insulator 200 that extends to the outside of the housing 30 and pulling it out.

Next, in step S60, as shown in FIG. 6C, a connection procedure is performed in which the fastening bolts 44 are fastened to the connection terminals 40 through the holes 33A of the bottom portion 33. As shown in FIG. As a result, the gap between the connection terminal 40 and the bottom portion 33 is connected by the fastening bolt 44, and the connection terminal 40 is electrically connected to the ground potential. In this state, the ground electrodes of the Y capacitors 14B and 14C become the ground potential, and the filter circuit 14 of the power supply section 10 functions. Since the connection terminals 40 are arranged on the outer edge of the housing 30, the operation of tightening the fastening bolts 44 can be performed with greater freedom of tool handling than when the connection terminals are located near the center of the housing 30. The degree is increased, and the work time can be shortened.

The embodiment of the present invention configured as described above is applied to the power supply device 1 that supplies power to the load 20 (the inverter circuit 21 and the motor 2). The power supply device 1 includes a power supply unit 10 that outputs power to a power supply line 13 composed of a positive electrode 13P and a negative electrode 13N, and a housing 30 that houses the power supply unit 10 and has a ground potential. The power supply unit 10 includes a pair of Y capacitors 14B and 14C interposed between the positive electrode 13P and the negative electrode 13N and the housing 30. As shown in FIG. The power supply unit 10 includes connection terminals 40 connected to the Y capacitors 14B and 14C and arranged with a non-conducting gap with respect to the housing 30, and detachable from the outside of the housing 30. and a conducting means (fastening bolt 44) for electrically connecting the housing 30 and the connection terminal 40 by connecting the gap while attached to the housing 30 .

With such control, the connection terminals 40 arranged between the Y capacitors 14B, 14C and the housing 30 are insulated from the ground potential by having the gaps, and the fastening bolts 44 are fixed, thereby It is possible to switch to a state of conducting to the ground potential. With such a configuration, the connection terminal 40 can be insulated from the ground potential when performing a dielectric strength test, for example, and the Y capacitors 14B and 14C can be connected to the ground potential after the test. There is no need to increase the capacity or increase the resistance of the Y capacitors 14B and 14C, thereby suppressing an increase in cost.

Further, in this embodiment, the gap is formed as a gap capable of sandwiching the insulator 200, and the conducting means is attached with the insulator 200 removed to the outside of the housing 30. When not attached, the degree of insulation between the connection terminals 40 and the housing 30 is enhanced.

Further, in the present embodiment, since the conducting means is the fastening bolt 44 that is fastened to the connection terminal 40 from the outside of the housing 30 through the hole 33A formed in the housing 30, the fastening bolt 44 is fastened. The connection terminal 40 can be electrically connected to the ground potential by a simple operation of doing so.

In addition, in the present embodiment, the connection terminals 40 are arranged on the outer edge of the housing 30, so that the work of fastening the fastening bolts 44 to the connection terminals 40 is facilitated, and the work time can be shortened.

In addition, in this embodiment, the housing 30 is composed of a box-shaped body portion 32 with an open bottom and a bottom portion 33 that covers the open portion of the body portion 32. It is fastened to the connection terminal 40 via the hole 33A formed in the bottom 33 . With such a configuration, a simple operation of fastening the fastening bolt 44 through the hole 33</b>A of the bottom portion 33 can electrically connect the connection terminal 40 to the ground potential.

In addition, in the present embodiment, the insulator 200 extends to the outside of the housing 30 from a gap formed between the main body portion 32 and the bottom portion 33. By pulling out the extended portion, the insulator 200 can be insulated. It is configured such that the body 200 can be removed from the housing 30 . Thereby, the insulator 200 sandwiched between the connection terminal 40 and the housing 30 can be removed to the outside of the housing 30 without disassembling the power supply device 1 .

Further, in the present embodiment, in a state in which the connection terminal 40 and the housing 30 are insulated, an alternating current is applied between the positive electrode 13P and the negative electrode 13N of the power supply unit 10 and the housing 30 to perform a dielectric strength test. It has a test procedure, and a connection procedure in which, after the test procedure, a conductive means is attached from the outside of the housing 30 to electrically connect the connection terminal 40 and the housing 30 . As a result, no test current flows through the Y capacitors 14B and 14C during the withstand voltage test, and the Y capacitors 14B and 14C can function as Y capacitors after the test. Therefore, the dielectric strength test can be performed without increasing the cost.

Further, in the present embodiment, prior to the test procedure, the insulator 200 is sandwiched between the connection terminal 40 and the housing 30, and after the test procedure and prior to the connection procedure, the connection terminal 40 and the housing 30 are separated. Insulator 200 is removed from the gap. As a result, the degree of insulation between the connection terminals 40 and the housing 30 can be increased during the withstand voltage test.

Although the embodiments of the present invention and their modifications have been described above, the above embodiments and modifications merely show a part of the application examples of the present invention, and the technical scope of the present invention is limited to the above embodiments. It is not intended to be limited to a specific configuration.

In the above-described embodiment, the insulator 200 is configured to extend outside the housing 30 from the gap between the cutout portion 36A of the bottom portion 33 and the cooling water outlet 36, but the present invention is not limited to this. In a configuration in which no gap is formed when the bottom portion 33 and the main body portion 32 are fixed by the fixing portion, only one fixing hole 31 adjacent to the connection terminal 40 is provided as in the modification shown in FIG. may be configured such that the fixing member is not fastened in advance. With such a configuration, the insulator 200 can be extended to the outside of the housing 30 through the gap generated near the fixing hole 31 .

In such a configuration, after the end of the test, the insulator 200 is removed to the outside of the housing 30, the fastening bolt 44 is fixed to the connection terminal 40, and the fixing member is fastened to the fixing hole 31, thereby can be configured to close the gap between

Further, in the above embodiment, the connection terminal 40 is configured to be arranged between the cooling water inlet 35 and the cooling water outlet 36 in the housing 30, but it is not limited to this. The connection terminals 40 may be placed anywhere as long as they can be placed on the outer edge of the housing 30 .

1: power supply device, 10: power supply unit, 11: power supply circuit, 13: power supply line, 13N: negative electrode, 13P: positive electrode, 14: filter circuit, 14A: X capacitor, 14B: Y capacitor, 14C: Y capacitor, 20: load, 21: inverter circuit, 30: housing, 32: main body, 33: bottom, 33A: hole, 35: cooling water inlet, 35A: notch, 36: cooling water outlet, 36A: notch, 38: cooling water flow path, 40: connection terminal, 44: fastening bolt (conducting means), 200: insulator

Claims (8)

A power supply that supplies power to a load,
a power supply unit that outputs power to a power supply line composed of a positive electrode and a negative electrode;
a housing that accommodates the power supply unit and serves as a ground potential;
with
The power supply unit
a set of Y capacitors interposed between the positive and negative electrodes and the housing;
a connection terminal connected to the Y capacitor and arranged with a non-conducting gap with respect to the housing;
a conductive means that is detachable from the outside of the housing and electrically connects the housing and the connection terminal by connecting the gap while attached to the housing,
Power supply. The power supply device according to claim 1,
The gap is formed as a gap capable of sandwiching an insulator,
the conducting means is mounted with the insulator removed to the outside of the housing;
Power supply. The power supply device according to claim 1 or 2,
The conducting means is a bolt fastened to the connection terminal from the outside of the housing through a hole formed in the housing.
Power supply. The power supply device according to any one of claims 1 to 3,
the conducting means is arranged at an outer edge portion of the housing,
Power supply. The power supply device according to any one of claims 1 to 4,
The housing comprises a box-shaped main body portion with an open bottom side, and a bottom portion that closes the open portion of the main body portion,
The conducting means is fastened to the connection terminal from the outside of the bottom through a hole formed in the bottom.
Power supply. The power supply device according to claim 5,
The insulator held in the gap extends outside the housing from the gap formed between the main body and the bottom, and the extended portion of the insulator is pulled out from the outside of the housing. By doing so, it is configured to be removable from the outside of the housing,
Power supply. A test method for a power supply device according to any one of claims 1 to 6,
A test procedure for performing a dielectric strength test by applying an alternating current between the positive and negative electrodes of the power supply unit and the housing while the connection terminal and the housing are insulated;
After the test procedure, a connection procedure of attaching the conduction means from the outside of the housing and electrically conducting the connection terminal and the housing;
having
Power supply test method. A test method for a power supply device according to claim 7,
Prior to the test procedure, sandwiching an insulator in the gap between the connection terminal and the housing,
After the test procedure and prior to the connection procedure, the insulator is removed from the gap between the connection terminal and the housing.
Power supply test method.

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