CN114062785A - Test circuit for insulation resistance jig of DOB high-voltage module - Google Patents

Abstract

The invention discloses a test circuit for an insulation resistance jig of a DOB high-voltage module, and relates to the technical field of insulation resistance tests. The circuit comprises an insulation resistance testing machine, a first point contact reset switch, a second point contact reset switch and a load resistor, wherein the L end of the insulation resistance testing machine is sequentially connected with the first point contact reset switch, a solder mask layer, a circuit layer, an insulation medium layer, a metal layer and the second point contact reset switch to the E end of the insulation resistance testing machine, the first point contact reset switch is connected with one end of the load resistor, and the other end of the load resistor is connected with an oxide layer G2, a G3, a G4 and the metal layer. The invention can better test the insulation performance of the product, has short test time, high test efficiency and good test safety, effectively solves the problems of misjudgment and missed test, can better control the safety performance of the product, and has low test cost and wide application prospect.

Description

Test circuit for insulation resistance jig of DOB high-voltage module

Technical Field

The invention relates to the technical field of insulation resistance testing, in particular to a test circuit for an insulation resistance jig of a DOB high-voltage module.

Background

At present, there are many insulation resistance tests for existing DOB high voltage modules, wherein the following two are commonly used: one is that before the metal aluminum substrate is not made into a DOB high-voltage module, a high-voltage tester is used for testing whether the metal aluminum substrate has the ultra-leakage or not by using fixed current and fixed voltage, and the insulation resistance value can be calculated by R = U/I through fixedly testing the voltage and the leakage current between a copper foil layer of the metal aluminum substrate and a metal oxide layer; the other method is to set a fixed voltage value by using an edge impedance machine after the DOB high-voltage module is manufactured, and test the impedance value between a copper foil layer (a circuit layer) and a metal oxide layer of the DOB high-voltage module, namely the insulation impedance value of the DOB high-voltage module. Specifically, the method comprises the following steps:

(1) and (3) testing the insulation resistance mode by using a high-voltage tester: through the voltage and the current of setting for high voltage test instrument, the voltage value that metal aluminium base board copper foil layer (circuit layer) and aluminum plate (metal layer) can bear in certain time, after setting for the completion back high voltage test and pressing the start button, the voltage acts on between copper foil (circuit layer) and the oxide layer through test instrument, measures the leakage current, uses the ohm's law R = U/I can draw insulation resistance.

This solution has the following drawbacks: firstly, only a metal aluminum plate can be tested, and the product cannot be used and produced after the test; secondly, the product after the test has damage risk; thirdly, the whole batch of all tests cannot be realized; the tester is unsafe and has electric shock risk; the tested product can not be used, and the cost is wasted; sixthly, the risk of missing measurement can occur due to poor contact; and the algorithm of the result is complex.

(2) Direct test mode of the insulation resistance machine: setting the voltage of an insulation resistance instrument, testing the insulation resistance of the DOB high-voltage module in time, testing the time by setting the voltages at two ends of the insulation resistance instrument, and after starting equipment, directly acting the voltages at two ends of the insulation resistance instrument on the copper foil layer to the oxide layer to obtain the insulation resistance.

This solution has the following drawbacks: firstly, the safety of testing personnel cannot be guaranteed, and the risk of electric shock exists; secondly, the risk of missing measurement can occur due to poor contact; the safety performance of the product cannot be controlled; fourthly, the operation mode is complex, an aluminum sheet needs to be locked manually, and the test is carried out after welding wires; testing for a long time; sixthly, the oxide layer is not conductive, and the metal layer cannot be detected with high probability under the action of the oxide layer, so that the misjudgment risk exists.

In order to solve the above problems, it is particularly necessary to develop a test circuit for a DOB high voltage module insulation resistance fixture.

Disclosure of Invention

Aiming at the defects in the prior art, the invention aims to provide the test circuit for the DOB high-voltage module insulation impedance jig, which has the advantages of simple structure, reasonable design, convenience in manufacturing, capability of better testing the insulation performance of a product, high test efficiency, high safety, low cost, strong practicability and easiness in popularization and use.

In order to achieve the purpose, the invention is realized by the following technical scheme: the utility model provides a DOB high voltage module insulation resistance tool test circuit, including insulation resistance test machine, first point touches reset switch, second point touches reset switch and load resistance, insulation resistance test machine's L end connects gradually first point touches reset switch, the solder mask, the circuit layer, insulating dielectric layer, the metal level, second point touches reset switch to insulation resistance test machine's E end, first point touches reset switch and load resistance's one end and links to each other, oxide layer G2, G3, G4 to metal level are connected to load resistance's the other end.

When the first point contact reset switch and the second point contact reset switch are conducted, after a machine starting key of the insulation resistance testing machine is pressed down, the insulation resistance machine generates set voltage and current, and the voltage and current pass through the loop to measure insulation resistance.

Preferably, the resistance value of the load resistor is between 50 and 1000M omega, and the resistance value of the load resistor is smaller than that of the DOB high-voltage module. When the high-voltage DOB module value is detected to be smaller than or equal to the resistance value of the load resistor, the high-voltage DOB module has large leakage current, and the product is judged to be unqualified; when the impedance of the high-voltage DOB module is detected to be equal to 0, the high-voltage DOB module is judged to be broken down and cannot be used; when the impedance of the high-voltage DOB module is detected to have no resistance value, the poor line contact or the no-good placement of the high-voltage DOB module is judged.

Preferably, the test time of the insulation resistance tester is set to be 0.3-999.9s, preferably 3-60s, the lower limit alarm resistance is 100K Ω -9.999G Ω, preferably 2-10M Ω, and the test voltage is four grades of 100V, 250V, 500V and 1000V.

The invention has the beneficial effects that: the circuit is convenient to manufacture, can be used for better testing the insulating property of a product, is short in testing time, improves testing efficiency, is high in testing safety, can protect the tested product from being damaged, solves the problems of misjudgment and missing test, and is low in testing cost and wide in application prospect.

Drawings

The invention is described in detail below with reference to the drawings and the detailed description;

FIG. 1 is a diagram of a DOB high voltage module test circuit according to the present invention;

fig. 2 is a circuit block diagram of the present invention.

Detailed Description

In order to make the technical means, the creation characteristics, the achievement purposes and the effects of the invention easy to understand, the invention is further described with the specific embodiments.

Referring to fig. 1-2, the following technical solutions are adopted in the present embodiment: a test circuit for an insulation resistance jig of a DOB high-voltage module comprises an insulation resistance test machine 1, a first point contact reset switch SW1, a second point contact reset switch SW2 and a load resistor RL, wherein the L end of the insulation resistance test machine 1 is sequentially connected with the first point contact reset switch SW1, a solder mask layer 2, a circuit layer 3, an insulation medium layer 4, a metal layer 5, the second point contact reset switch SW2 and the E end of the insulation resistance test machine 1, the first point contact reset switch SW1 is connected with one end of the load resistor RL, and the other end of the load resistor RL is connected with an oxide layer G2, a G3, a G4 and the metal layer 5. When the first and second touch reset switches SW1 and SW2 are turned on, and the machine start button of the insulation resistance tester 1 is pressed, the insulation resistance machine generates a voltage current set at that time, and the voltage current flows through the flow direction shown in fig. 2, so as to measure the insulation resistance.

It is noted that the resistance value of the load resistor RL is between 50 and 1000M Ω.

The insulation resistance tester 1 of the present embodiment requires a parameter setting method before use, and the setting method includes:

(1) by "setting" key selection "test time of the tester," measurement range: any value of 0.3-999.9S is used as the test time, and the setting of the measurement time can be completed by pressing a 'confirm' key generally by 3-60S;

(2) pressing the ' set ' key to select ' low resolution ', setting ' low resolution: any value of 100K omega-9.999G omega is used as the lower limit alarm impedance, and the setting of the lower limit alarm impedance can be completed by generally selecting 2-10M omega and pressing a 'confirm' key;

(3) pressing the set key to select the automatic range, and setting the measurement range: ON, pressing the confirm key, testing and reading parameters, opening the computer software, and reading the parameters of the impedance meter;

(4) pressing a 'set' key, selecting a 'test voltage', wherein the test voltage has four levels of 100V, 250V, 500V and 1000V, one level can be selected from the gear voltage to be used as the test voltage, and pressing a 'confirm' key;

(5) and pressing an exit key to exit, and finishing the setting of the parameters.

When the first point-contact reset switch SW1 and the second point-contact reset switch SW2 are closed, the load resistor RL is connected between the first point-contact reset switch SW1 and the metal layer 5 through the oxide layers G2, G3 and G4. When the DOB high-voltage module normally has no electric leakage, the impedance from the solder mask layer 2L 1/N to the metal layer 5 is close to infinity, the insulation impedance tester 1 cannot show the impedance value of the DOB module, the open circuit or poor contact of the circuit also shows that the impedance is infinity, the impedances of the two are close, whether the insulation impedance of the DOB high-voltage module is normal or not cannot be judged, and the load resistor RL is connected, because the resistance value of the load resistor RL is 50-1000 MOmega, the resistance value is smaller than that of the DOB high-voltage module, the measured DOB insulation impedance value is larger than that of the selected load resistor RL. When the high-voltage DOB module value is detected to be smaller than or equal to the resistance value of the load resistor RL, the high-voltage DOB module has large leakage current, and the product can be judged to be unqualified; when the impedance of the high-voltage DOB module is detected to be equal to 0, the high-voltage DOB module can be judged to be broken down and can not be used; when the impedance of the high-voltage DOB module is measured and the resistance value is not displayed, the poor line contact or the no-good high-voltage DOB module can be judged, and the tested DOB module does not have the misjudgment risk.

The technical advantages of this embodiment are:

test safety is high: when first point touch reset switch SW1, second point touch reset switch SW2 disconnection, at the start-up button of testing artifical maloperation insulation resistance appearance, voltage and current also can not flow through between test end L1 and the G1 to the personal safety of protection tester when the test product avoids electric shock danger, accomplishes the prevention accident and takes place, also protects simultaneously to be surveyed the product and not damaged.

Secondly, the E end of the insulation resistance testing machine 1 is directly connected to the G1 after passing through the second point contact reset switch SW2, the G1 end has no metal oxide layer, and the contact positions of the G2, the G3 and the G4 have metal oxide layers, if the G2, the G3 and the G4 points are directly connected to the E end of the insulation resistance testing machine 1, the phenomenon that the insulation resistance is not accurately measured due to poor contact can occur; the circuit not only avoids the defects generated by connecting the metal oxide layers, but also greatly improves the insulation resistance generated by poor contact in a contact mode and prevents the defective products from flowing into the market.

The testing method is simple, simple and convenient to implement, short in testing time and easy to operate, testing efficiency can be further improved, product insulation performance can be better tested, production is simplified, and testing cost is saved.

The safety performance of the product can be better controlled, the test circuit scheme can ensure that 100 percent of DOB high-voltage modules can be tested, the automatic alarm of equipment can be set, the equipment with the impedance exceeding the upper limit or the lower limit can alarm and prompt operating personnel, and thus the test product cannot be missed to be tested.

The foregoing shows and describes the general principles and broad features of the present invention and advantages thereof. It will be understood by those skilled in the art that the present invention is not limited to the embodiments described above, which are described in the specification and illustrated only to illustrate the principle of the present invention, but that various changes and modifications may be made therein without departing from the spirit and scope of the present invention, which fall within the scope of the invention as claimed. The scope of the invention is defined by the appended claims and equivalents thereof.

Claims (4)

1. A test circuit for an insulation resistance jig of a DOB high-voltage module is characterized by comprising an insulation resistance test machine (1), a first point contact reset switch (SW1), a second point contact reset switch (SW2) and a load Resistor (RL), wherein the L end of the insulation resistance test machine (1) is sequentially connected with the first point contact reset switch (SW1), a solder mask layer (2), a circuit layer (3), an insulation dielectric layer (4), a metal layer (5) and the second point contact reset switch (SW2) to the E end of the insulation resistance test machine (1), the first point contact reset switch (SW1) is connected with one end of the load Resistor (RL), and the other end of the load Resistor (RL) is connected with an oxide layer G2, a G3 and a G4 to the metal layer (5); when the first point contact reset switch (SW1) and the second point contact reset switch (SW2) are turned on, and a machine starting key of the insulation resistance testing machine (1) is pressed, the insulation resistance machine generates a set voltage current, and the voltage current passes through the loop to measure the insulation resistance.

2. The test circuit of the insulation resistance jig of the DOB high-voltage module according to claim 1, wherein the resistance value of the load Resistor (RL) is between 50 and 1000 MOmega, and the resistance value of the load Resistor (RL) is smaller than that of the DOB high-voltage module; when the high-voltage DOB module value is detected to be smaller than or equal to the resistance value of a load Resistor (RL), the high-voltage DOB module has large leakage current, and the product is judged to be unqualified; when the impedance of the high-voltage DOB module is detected to be equal to 0, the high-voltage DOB module is judged to be broken down and cannot be used; when the impedance of the high-voltage DOB module is detected to have no resistance value, the poor line contact or the no-good placement of the high-voltage DOB module is judged.

3. A test circuit for insulation resistance jig of DOB high voltage module according to claim 1, characterized in that the test time of the insulation resistance tester (1) is set to 0.3-999.9s, the lower limit alarm resistance is 100K Ω -9.999G Ω, and the test voltage is four levels of 100V, 250V, 500V and 1000V.

4. A DOB high voltage module insulation resistance jig test circuit according to claim 3, characterized in that the test time of the insulation resistance tester (1) is preferably 3-60s, and the lower limit alarm resistance is preferably 2-10M Ω.

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