KR20110045405A - Current measuring module in test-apparatus for testing power semiconductor module - Google Patents

Abstract

PURPOSE: A current measuring module in an apparatus for testing a power semiconductor module is provided to reduce parasitic inductance caused by connection lines, thereby accurately measuring currents flowing in a busbar. CONSTITUTION: A first current transformer comprises a first ring shaped core(610) and a first coil(620). A first busbar(402) passes the first ring shaped core. A first connection line(630) is connected to both ends of the first coil. The second current transformer(750) comprises a second ring shaped core. The second current transformer detects currents outputted from the first current transformer.

Description

CURRENT MEASURING MODULE IN TEST-APPARATUS FOR TESTING POWER SEMICONDUCTOR MODULE}

The present invention relates to a current measuring module in a power semiconductor module test apparatus for measuring a current flowing in a busbar.

An important part of the power semiconductor module is the switching loss of the semiconductor device.

In order to accurately test the power semiconductor module, it is necessary to accurately measure voltage and current. Conventional methods of measuring current include a Hall sensor and a Rogowski coil. However, since the methods are slow in response, the current is not measured accurately.

Therefore, there is an urgent need for a method of measuring current using a device having a fast response speed.

An object of the present invention is to provide a current measuring module in a power semiconductor module test apparatus equipped with a fast response current measuring apparatus.

The current measuring module according to the present invention includes a first current transformer including a first ring-shaped core through which a first busbar passes and a first coil wound around the first ring-shaped core, and having a volume larger than that of the first ring-shaped core. A second current transformer including a second ring-shaped core and a first connecting line passing through the second ring-shaped core and connected to both ends of the first coil.

Here, the current measuring module includes a third current transformer including a third ring-shaped core through which a first busbar passes and a second coil wound around the third ring-shaped core, and the second coil through the third ring-shaped core. It further includes a second connection line connected to both ends of the.

Here, the current measuring module includes a third current transformer comprising a third ring-shaped core through which a second busbar passes and a second coil wound around the third ring-shaped core, and the second coil through the third ring-shaped core. It further includes a second connection line connected to both ends of the.

Here, the first connection line has a form in which two strands of the connection line formed between the first current transformer and the second current transformer are twisted.

Here, the first ring-shaped core is located at the same distance from the center point of the first busbar.

Another current measuring module of the present invention includes a first current transformer including a first ring-shaped core through which a first busbar passes and a first coil wound around the first ring-shaped core, and at both ends of the first coil. And a resistor connected to the amplifier, an amplifier configured to amplify and output the voltage applied to the resistor, and an integrator configured to integrate and output the output signal of the amplifier.

According to the present invention, as the response speed increases, current can be measured more accurately.

1 is a configuration diagram of a power semiconductor module test apparatus to which a current measuring module according to the present invention may be applied.

Referring to FIG. 1, the power semiconductor module test apparatus includes a power supply unit 100, a power semiconductor module 200, a capacitor bank 400, an inductor 410, a first current transformer 600, and a compensation circuit unit 700. It includes a measuring unit 800.

The power supply unit 100 supplies power to the capacitor bank 400. The power is applied to the power semiconductor module 200 through the capacitor bank 400.

The power semiconductor module 200 includes a first connection terminal 201, a second connection terminal 202, a third connection terminal 203, and a fourth connection terminal 204. The connection terminals 201, 202, 203, and 204 will be described with reference to FIG. 9 below.

The capacitor bank 400 includes a plurality of capacitors, a wire for connecting the plurality of capacitors, a bus bar, and the like. The capacitor bank 400 is configured to charge a voltage using the plurality of capacitors and then discharge the voltage according to a control signal. In addition, the capacitor bank 400 includes bus bars 401 and 402 provided to connect with the power semiconductor module 200.

The inductor 410 is used as a load in the present invention.

The first transformer 600 includes a ring core and a coil wound around the ring core. The busbar 402 passes through the ring core.

The compensation circuit unit 700 detects and outputs a current from the first current transformer. A detailed configuration of the compensation circuit unit 700 will be described with reference to FIG. 6 below. In addition, the compensation circuit unit 700 may be replaced by a current transformer, a detailed configuration thereof will be described with reference to FIGS. 3 to 5 below.

The measurement unit 800 measures the current output from the compensation circuit unit 700. In addition, the measurement unit 800 may measure a voltage by connecting a probe to the second connection terminal and the third connection terminal.

The controller (not shown) generally controls the power semiconductor module test apparatus. For example, the controller may control to display the measured temperature, current, voltage, and the like on a display unit (not shown) or to generate a control signal for driving the power semiconductor module.

Hereinafter, embodiments of the current measuring module according to the present invention that can be applied to the power semiconductor module test apparatus will be described with reference to FIGS. 3 to 6.

FIG. 2 is a circuit diagram of the power semiconductor module test apparatus shown in FIG. 1.

The power supply unit 100 is connected in parallel with the capacitor bank 400 and supplies power to the capacitor bank 400. The power semiconductor module 200 is connected in parallel with the capacitor bank 400. The power semiconductor module 200 includes a first IGBT 210 and a second IGBT 220. Inductor 410 is connected in series with the first IGBT 210. The parasitic inductance 600 is generated according to the distance between the components.

When the circuit diagram and the power semiconductor module 200 are matched, the first connection terminal 201 corresponds to a node existing between the first IGBT 210 and the power supply 700, and the second connection is performed. The terminal 202 corresponds to a node existing between the first IGBT 210 and the second IGBT 220. In addition, the third connection terminal 203 corresponds to a node existing between the second IGBT 220 and the ground, and the fourth connection terminal 204 corresponds to the first IGBT 210 and the second. Corresponds to the node connected to the gate of the IGBT 220.

3 is a configuration diagram illustrating a first embodiment of a current measuring module according to the present invention.

The current measuring module includes a first current transformer 600, a first connection line 630, and a second current transformer 750.

The first current transformer 600 includes a first ring core 610 and a first coil 620 wound around the ring core. The first busbar 402 passes through the first ring-shaped core 610.

The first connection line 630 is connected to both ends of the first coil 620.

The second current transformer 750 includes a second ring-shaped core. The first connection line 630 is connected to both ends of the first coil 620 through the second ring-shaped core. Here, the second current transformer 750 is larger in volume than the first current transformer 600. Thus, the second current transformer 750 has a faster response speed. The second current transformer 750 detects the current output from the first current transformer 600. Then, the measuring unit 800 measures the current output from the second current transformer 750. The measured current value may be transmitted to the controller, and the controller may display the measured current value on the display unit.

Accordingly, as the response speed increases, the current flowing through the busbars can be measured more accurately.

In addition, by using a bulky (high performance) current transformer, the range of measurable currents can also be widened.

4 is a configuration diagram illustrating a second embodiment of a current measuring module according to the present invention.

The current measuring module includes a first current transformer 600, a first connection line 630, a second current transformer 750, and a third current transformer 900.

The first current transformer 600 includes a first ring core 610 and a first coil 620 wound around the ring core. The first busbar 402 passes through the first ring-shaped core 610.

The first connection line 630 is connected to both ends of the first coil 620.

The third current transformer 900 includes a third ring core 910 and a second coil 920 wound around the ring core. The first busbar 402 passes through the third ring-shaped core 910.

The second connection line 670 is connected to both ends of the second coil 920.

The length of the first connection line 630 and the second connection line 670 may be 6cm or more and 60cm or less. This is because the longer the length of the line, the larger the parasitic inductance, so the shorter the length of the line is better.

The second current transformer 750 includes a second ring-shaped core. The first connection line 630 and the second connection line 670 pass through the second ring-shaped core and are connected to both ends of the first coil 620. The second current transformer 750 detects both currents output from the first current transformer 600 and the second current transformer 900. That is, the first and third current transformers and the second current transformer are connected in parallel. When the current flowing through the first busbar 402 is insignificant and the signal transmitted to the second current transformer 750 is insignificant, the signal may be amplified by using the first and third current transformers as described above. Accordingly, the signal input to the second current transformer is amplified. When a signal is output from the second current transformer 750, the measurement unit 800 measures a current from the second current transformer 750. The measured current value is transmitted to the controller, and the controller may display the measured current value on the display unit.

In the above, the case where two current transformers are used for one busbar is described, but the number of the current transformers may be one or more.

Accordingly, as the response speed increases, the current flowing through the busbars can be measured more accurately.

In addition, even when the current flowing through the busbar is small, the current can be measured accurately.

5 is a configuration diagram illustrating a third embodiment of a current measuring module according to the present invention.

The current measuring module includes a first current transformer 600, a first connection line 630, a second current transformer 750, and a third current transformer 900. This embodiment relates to a current measurement module that can be applied to the case of two busbars.

The first current transformer 600 includes a first ring core 610 and a first coil 620 wound around the ring core. The first busbar 402 passes through the first ring-shaped core 610.

The first connection line 630 is connected to both ends of the first coil 620.

The third current transformer 900 includes a third ring core 910 and a second coil 920 wound around the ring core. The second busbar 950 passes through the third ring-shaped core 910.

The second connection line 670 is connected to both ends of the second coil 920.

The second current transformer 750 includes a second ring-shaped core. The first connection line 630 and the second connection line 670 pass through the second ring-shaped core and are connected to both ends of the first coil 620. The second current transformer 750 detects both currents output from the first current transformer 600 and the second current transformer 900. That is, the first and third current transformers and the second current transformer are connected in parallel. When a signal is output from the second current transformer 750, the measurement unit 800 measures a current from the second current transformer 750. The measured current value is transmitted to the controller, and the controller may display the measured current value on the display unit.

In the above, the case in which the current transformers are used in each of the two busbars has been described, but the number of the busbars and the number of current transformers may be one or more.

Accordingly, when the magnitude of the current is large, it may be useful when the busbar is divided into two or more measurements. Alternatively, this embodiment may be useful when simultaneously measuring currents flowing in two or more busbars.

6 is a configuration diagram illustrating a fourth embodiment of the current measurement module according to the present invention.

The current measuring module includes a first current transformer 600, a first connection line 630, and a compensation circuit unit 700.

The first current transformer 600 includes a first ring core 610 and a first coil 620 wound around the ring core. The first busbar 402 passes through the first ring-shaped core 610.

The first connection line 630 is connected to both ends of the first coil 620.

The compensation circuit unit 700 includes a resistor 710, an amplifier 720, and an integrator 730. Both ends of the resistor 710 are connected by the first connection line 630. The amplifier 720 amplifies and outputs the voltage 710 applied to the resistor. The integrator 730 integrates and outputs an output signal of the amplifier 710. Then, the measuring unit 800 measures the current based on the signal output from the integrator 730.

As described with reference to FIGS. 4 and 5, the present embodiment may be applied to a case in which a plurality of current transformers are used for one busbar or a current transformer is used for two or more busbars, respectively.

Thus, the current flowing through the busbars can be measured more accurately.

7 is a configuration diagram for explaining the configuration of the current transformer in the current measuring module according to the present invention.

Referring to FIG. 7, the first current transformer 600 of the current measuring module detects a current flowing in the first busbar 402. The first current transformer 600 includes a first ring-shaped core 610 and a first coil 620, and the first bus bar 402 passes through the first ring-shaped core 610. At this time, the distance from the center point of the first busbar 402 to the first ring-shaped core 610 should always be kept constant. This is because, if the distance varies each time the current is measured, the current is not measured accurately as the magnetic field is changed. The distance from the center point of the first bus bar 402 to the first ring-shaped core 610 is preferably 2 mm or more and 48 mm or less. The number of turns of the first coil 620 wound on the first ring-shaped core 610 may be 10 or more and 500 or less. However, it is not limited to the above numerical values.

Thus, the current flowing through the busbars can be measured more accurately.

8 is a configuration diagram for explaining the configuration of a connection line in the current measurement module according to the present invention.

Referring to FIG. 8, the connecting line 630 of the current measuring module includes two strands of connecting lines 630-1 and 630-2 formed between the first current converter and the second current converter or between the first current converter and the compensation circuit unit. It is composed of The two strands 630-1 and 630-2 may be implemented in a twisted form. By doing so, parasitic inductance generated by the connecting lines can be reduced.

Thus, the current flowing through the busbars can be measured more accurately.

Although the technical spirit of the present invention has been described in detail according to the above-described preferred embodiment, it should be noted that the above-described embodiment is for the purpose of description and not of limitation. In addition, those skilled in the art will understand that various embodiments are possible within the scope of the technical idea of the present invention.

1 is a configuration diagram of a power semiconductor module test apparatus to which the current measuring module according to the present invention may be applied.

FIG. 2 is a circuit diagram of the power semiconductor module test apparatus shown in FIG. 1. FIG.

3 is a configuration diagram for explaining a first embodiment of a current measuring module according to the present invention;

Figure 4 is a block diagram for explaining a second embodiment of the current measuring module according to the present invention.

5 is a configuration diagram for explaining a third embodiment of a current measurement module according to the present invention;

6 is a configuration diagram for explaining a fourth embodiment of the current measuring module according to the present invention;

7 is a configuration diagram for explaining the configuration of the current transformer in the current measuring module according to the present invention.

8 is a configuration diagram for explaining the configuration of the connection line in the current measuring module according to the present invention.

Claims (6)

In the current measurement module of the power semiconductor module test apparatus, A first current transformer comprising a first ring-shaped core through which a first busbar is passed and a first coil wound around the first ring-shaped core; A second current transformer comprising a second ring-shaped core having a volume larger than that of the first ring-shaped core; And And a first connection line passing through the second ring-shaped core and connected to both ends of the first coil. The method of claim 1, A third current transformer comprising a third ring-shaped core through which the first busbar is passed and a second coil wound around the third ring-shaped core; and And a second connection line passing through the third ring-shaped core and connected to both ends of the second coil. The method of claim 1, A third current transformer comprising a third ring-shaped core through which a second busbar is passed and a second coil wound around the third ring-shaped core; and  And a second connection line passing through the third ring-shaped core and connected to both ends of the second coil. The method of claim 1, The first connection line, 2. The current measuring module of claim 2, wherein two strands of the connection line formed between the first current transformer and the second current transformer are twisted. The method of claim 1, The first ring-shaped core, And a current measurement module located at the same distance from the center point of the first busbar. A first current transformer comprising a first ring-shaped core through which a first busbar is passed and a first coil wound around the first ring-shaped core; Resistors connected to both ends of the first coil; An amplifier configured to amplify and output the voltage across the resistor; And And an integrator configured to integrate and output the output signal of the amplifier.

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