KR102623885B1 - Insulation resistance measuring apparatus - Google Patents

Abstract

The present invention relates to an insulation resistance measuring device and a measuring method thereof, wherein the input terminal is connected to a battery, includes at least one insulation resistance, includes at least one distribution resistance, and outputs a sampling voltage when a battery voltage is applied from the battery. A sampling phase unit, connected to the output terminal of the sampling phase unit, including at least one capacitor, and amplifying the sampling voltage when the sampling voltage is applied to output an amplification voltage. Connected to the output terminal of the amplification phase unit and the amplifying unit. It includes an insulation resistance measuring unit that measures the output voltage relative to the voltage and measures the insulation resistance of the battery using the output voltage, and amplifies the sampling voltage applied to the distribution resistance, allowing accurate measurement even when a small voltage is applied. It relates to an insulation resistance measuring device and method of measuring insulation resistance that can shorten the measurement time of insulation resistance.

Description

Insulation resistance measuring apparatus}

The present invention relates to an insulation resistance measuring device and a method for measuring the same, and to a device for measuring the insulation resistance of a vehicle battery and a method for measuring the insulation resistance.

In electric vehicles or hybrid vehicles that use high-voltage batteries, the insulation resistance of the battery is very important because it indicates that a ground fault has occurred. For example, insulation resistance includes positive insulation resistance between the positive electrode of the battery and ground (for example, vehicle chassis ground), and negative insulation resistance between the negative electrode of the battery and ground.

Insulation resistance has an infinite value when a grounding fault does not occur, but when a grounding fault occurs, the resistance value becomes small.

Generally, the insulation resistance of a battery is measured using the voltage applied to the distribution resistance after forming a current path connected to the positive electrode of the battery, ground, and negative electrode of the battery.

Korea Patent Publication No. 10-2020-0109925 is presented as a prior document. The prior literature is an invention regarding an insulation resistance measuring device.

The prior literature includes a first distribution resistor connected to the positive terminal of the battery and the ground, a first switch connected to the positive terminal of the battery and the first distribution resistor, and a second distribution connected to the negative terminal of the battery and the ground. Measure the negative insulation resistance of the battery using a resistor, a second switch connected to the negative terminal of the battery and the second distribution resistor, and the first voltage applied to the first distribution resistor, and measure the negative insulation resistance of the battery to the second distribution resistor. It includes an insulation resistance measuring unit that measures the anode insulation resistance of the battery using the applied second voltage.

According to prior literature, by excluding components such as operational amplifiers and test circuits, the device for measuring the insulation resistance of a battery can be simplified, the cost can be reduced, and the measurement speed of the insulation resistance can be improved.

Meanwhile, the prior literature does not include an operational amplifier. According to prior literature, providing an operational amplifier or test circuit in an insulation resistance measurement device increases the complexity and price of the device, and the process of processing the voltage amplified by the operational amplifier must be added to the insulation resistance measurement unit. Therefore, the measurement speed of insulation resistance decreases. Accordingly, in the prior literature, components such as operational amplifiers or test circuits are excluded and the insulation resistance measurement unit is directly connected to the first distribution resistance and the second distribution resistance, thereby reducing the complexity and price of the insulation resistance measurement device. It is said to improve the measurement speed of insulation resistance.

However, since the prior literature does not include an operational amplifier, there is a problem in that it is difficult to detect if the leaked current is small.

Korean Patent Publication No. 10-2020-0109925

The present invention is intended to solve the problems of the prior literature as described above. In other words, the problem to be solved by the present invention is to provide an insulation resistance measurement device and method that is equipped with an operational amplifier to detect a low output voltage applied to the distribution resistance and has a fast measurement speed.

In order to achieve the above-described object, the insulation resistance measuring device according to the present invention has an input terminal connected to a battery, includes at least one insulation resistance, and includes at least one distribution resistance, and the battery voltage is adjusted from the battery. A sampling phase unit that outputs a sampling voltage when applied; an amplification phase unit connected to the output terminal of the sampling phase unit, including at least one capacitor, and amplifying the sampling voltage when the sampling voltage is applied to output an amplified voltage; It includes an insulation resistance measurement unit connected to the output terminal of the amplification phase unit, measuring an output voltage relative to the amplification voltage, and measuring the insulation resistance of the battery using the output voltage.

The sampling phase unit includes a positive insulation resistor, one end of which is connected to the positive electrode of the battery, and the other end of which is grounded; a first distribution resistor, one end of which is connected to the anode of the battery and disposed in parallel with the anode insulation resistor; a negative insulation resistance whose one end is connected to the negative electrode of the battery and the other end is grounded; It may include a second distribution resistor, one end of which is connected to the negative electrode of the battery and disposed in parallel with the negative electrode insulation resistance.

The sampling phase unit includes a first distribution resistor, one end of which is connected to the positive electrode of the battery; a first switch whose one end is connected to the first distribution resistor and the other end of which is connected to the output terminal of the sampling phase unit; a second distribution resistor, one end of which is connected to the negative electrode of the battery; It may include a second switch, one end of which is connected to the second distribution resistor, and the other end of which is connected to the output terminal of the sampling phase unit.

The sampling phase unit includes a first distribution resistor, one end of which is connected to the positive electrode of the battery, and the other end of which is connected to the output terminal of the sampling phase unit; a second distribution resistor with one end connected to the negative electrode of the battery and the other end connected to the output terminal of the sampling phase unit; It may include a third distribution resistor, one end of which is connected to the output terminal of the sampling phase unit, and the other end of which is grounded. At this time, the sampling phase unit may include a third switch, one end of which is connected to the output terminal of the sampling phase unit, the other end of which is grounded, and disposed in parallel with the third distribution resistor.

The amplification phase unit includes a first operational amplifier; an input capacitor with one end connected to the output terminal of the sampling phase unit and the other end connected to the input terminal of the first operational amplifier; It may include an output capacitor, one end of which is connected to the input terminal of the first operational amplifier, and the other end of which is connected to the output terminal of the first operational amplifier. At this time, the amplification phase unit includes a fourth switch, one end of which is connected to the input terminal of the first operational amplifier, the other end of which is connected to the output terminal of the first operational amplifier, and disposed in parallel with the output capacitor; It may include a fifth switch, one end of which is connected to the output terminal of the first operational amplifier, and the other end of which is grounded.

It may include an inverting amplifier disposed between the amplification phase unit and the insulation resistance measurement unit, including a plurality of amplification resistors, and transmitting an output voltage to the insulation resistance measurement unit in proportion to the amplification voltage.

In order to achieve the above-described object, the insulation resistance measurement method according to the present invention has an input terminal connected to a battery, includes at least one insulation resistance, and includes at least one distribution resistance, in a sampling phase unit, from the battery to the battery. When a voltage is applied, outputting a sampling voltage according to the voltage distribution principle; generating an amplified voltage by amplifying the sampling voltage according to the law of charge conservation when the sampling voltage is applied, in an amplification phase unit connected to the output terminal of the sampling phase unit and including at least one capacitor; Measuring an output voltage related to the amplification voltage in an insulation resistance measurement unit connected to the output terminal of the amplification phase unit; Comparing the output voltage with a previously stored reference value.

The sampling phase unit includes a positive insulation resistor, one end of which is connected to the positive electrode of the battery, and the other end of which is grounded; a first distribution resistor, one end of which is connected to the anode of the battery and disposed in parallel with the anode insulation resistor; a first switch whose one end is connected to the first distribution resistor and the other end of which is connected to the output terminal of the sampling phase unit; A negative insulation resistance whose one end is connected to the negative electrode of the battery and the other end is grounded; a second distribution resistor, one end of which is connected to the negative electrode of the battery and disposed in parallel with the negative electrode insulation resistance; It may include a second switch, one end of which is connected to the second distribution resistor, and the other end of which is connected to the output terminal of the sampling phase unit. At this time, in the step of outputting the sampling voltage, one of the first switch or the second switch may alternatively be turned on and the other switch may be turned off.

The sampling phase unit includes a third distribution resistor, one end of which is connected to the output terminal of the sampling phase unit, and the other end of which is grounded; It may include a third switch, one end of which is connected to the output terminal of the sampling phase unit, the other end of which is grounded, and disposed in parallel with the third distribution resistor. At this time, the third switch may be turned off in the step of outputting the sampling voltage and turned on in the step of outputting the amplification voltage.

Specific details of other embodiments are included in the detailed description and drawings.

According to the insulation resistance measuring device and method of the present invention, one or more of the following effects are achieved.

First, the insulation resistance measurement device includes an amplification phase unit with an operational amplifier and an inverting amplifier unit with an operational amplifier. It amplifies the sampling voltage applied to the distribution resistance, allowing accurate measurement even when a small voltage is applied. There is an advantage to having it.

Second, the amplification phase unit is composed of a combination of a plurality of capacitors and switches, and as the switches are operated sequentially, the voltage is amplified in a short time according to the law of charge conservation, which also has the advantage of shortening the measurement time of insulation resistance.

The effects of the present invention are not limited to the effects mentioned above, and other effects not mentioned will be clearly understood by those skilled in the art from the description of the claims.

1 is a diagram briefly showing the components of an insulation resistance measuring device according to the present invention;
Figure 2 is an internal circuit diagram of the insulation resistance measuring device according to the present invention;
Figure 3 is a circuit diagram of the sampling phase step for measuring the anode insulation resistance in Figure 2;
Figure 4 is a circuit diagram of the amplification phase step for measuring the anode insulation resistance in Figure 2;
Figure 5 is a circuit diagram of the sampling phase step for measuring the cathode insulation resistance in Figure 2;
Figure 6 is a circuit diagram of the amplification phase step for measuring the cathode insulation resistance in Figure 2;
Figure 7 is a graph of the output voltage measured by the insulation resistance measurement unit,
Figure 8 is a flowchart of the insulation resistance measurement method according to the present invention.

Hereinafter, preferred embodiments of the present invention will be described in detail with reference to the attached drawings.

Since the present invention can make various changes and have various embodiments, specific embodiments will be illustrated in the drawings and described in detail in the detailed description. This is not intended to limit the present invention to specific embodiments, and should be interpreted as including all changes, equivalents, and substitutes included in the spirit and technical scope of the present invention.

In describing the present invention, terms such as first and second may be used to describe various components, but the components may not be limited by the terms. The above terms are solely for the purpose of distinguishing one component from another. For example, a first component may be named a second component, and similarly, the second component may also be named a first component without departing from the scope of the present invention.

The term “and/or” may include any of a plurality of related stated items or a combination of a plurality of related stated items.

When a component is said to be "connected" or "connected" to another component, it means that it may be directly connected to or connected to that other component, but that other components may also exist in between. It can be understood. On the other hand, when a component is referred to as being “directly connected” or “directly connected” to another component, it can be understood that there are no other components in between.

The terms used in this application are only used to describe specific embodiments and are not intended to limit the invention. Singular expressions may include plural expressions, unless the context clearly indicates otherwise.

In this application, terms such as “comprise” or “have” are intended to designate the presence of features, numbers, steps, operations, components, parts, or combinations thereof described in the specification, and one or more other features It can be understood that it does not exclude in advance the possibility of the existence or addition of elements, numbers, steps, operations, components, parts, or combinations thereof.

Unless otherwise defined, all terms used herein, including technical or scientific terms, may have the same meaning as commonly understood by a person of ordinary skill in the technical field to which the present invention pertains. Terms defined in commonly used dictionaries can be interpreted as having meanings consistent with the meanings they have in the context of related technologies, and unless clearly defined in this application, are interpreted as having an ideal or excessively formal meaning. It may not work.

In addition, the following examples are provided to provide a more complete explanation to those with average knowledge in the art, and the shapes and sizes of elements in the drawings may be exaggerated for clearer explanation.

The insulation resistance measuring device according to the present invention is connected to the battery 100 and can measure the insulation resistance when the battery voltage (Vb) is applied from the battery 100.

The battery 100 may be a driving battery disposed in an electric vehicle. Alternatively, the battery may be placed in an internal combustion engine.

The battery 100 may be comprised of a plurality of battery cells connected in series or parallel.

The insulation resistance measurement device according to the present invention can be divided into a sampling phase unit 200, an amplification phase unit 300, an inversion amplification unit 400, and an insulation resistance measurement unit 500.

The sampling phase unit 200 is a component that outputs a sampling voltage (Vd) when the battery voltage (Vb) is applied from the battery 100.

The sampling phase unit 200 has an input terminal connected to the battery 100, includes at least one insulation resistor, and includes at least one distribution resistor.

The input terminal of the sampling phase unit 200 is connected to the battery 100, and the output terminal of the sampling phase unit 200 is connected to the amplification phase unit 300.

The sampling phase unit 200 includes an anode insulation resistance 210, a cathode insulation resistance 220, a first distribution resistor 230, a first switch 240, a second distribution resistor 250, and a second switch 260. , It may be composed of a third distribution resistor 270 and a third switch 280.

The anode insulation resistance 210 is a virtual resistance that exists between the anode of the battery 100 and the vehicle body.

One end of the positive insulation resistor 210 is connected to the positive electrode of the battery 100, and the other end is grounded.

The resistance value of the anode distribution resistor is defined as RisoH.

The cathode insulation resistance 220 is a virtual resistance that exists between the cathode of the battery 100 and the vehicle body.

One end of the negative insulation resistor 220 is connected to the negative electrode of the battery 100, and the other end is grounded.

The resistance value of the cathode distribution resistor is defined as RisoH.

The first distribution resistor 230 is a distribution resistor disposed at the positive electrode of the battery 100.

One end of the first distribution resistor 230 is connected to the anode of the battery 100 and is arranged in parallel with the anode insulation resistor 210. Specifically, one end of the first distribution resistor 230 is connected to the positive electrode of the battery 100, and the other end is connected to the output terminal of the sampling phase unit 200.

The resistance value of the first distribution resistor 230 is defined as Rd1.

The first switch 240 is a component that controls the current flowing through the first distribution resistor 230. One end of the first switch 240 is connected to the first distribution resistor 230, and the other end is connected to the output terminal of the sampling phase unit 200.

The second distribution resistor 250 is a distribution resistor disposed at the cathode of the battery 100.

One end of the second distribution resistor 250 is connected to the cathode of the battery 100 and is arranged in parallel with the cathode insulation resistor 220. Specifically, one end of the second distribution resistor 250 is connected to the negative electrode of the battery 100, and the other end is connected to the output terminal of the sampling phase unit 200.

The resistance value of the second distribution resistor 250 is defined as Rd2.

The second switch 260 is a component that controls the current flowing in the second distribution resistor 250. One end of the second switch 260 is connected to the second distribution resistor 250, and the other end is connected to the output terminal of the sampling phase unit 200.

The third distribution resistor 270 is a distribution resistor disposed at the output terminal of the sampling phase unit 200 and is a component that determines the size of the sampling voltage (Vd).

One end of the third distribution resistor 270 is connected to the output terminal of the sampling phase unit 200, and the other end is grounded.

The resistance value of the third distribution resistor 270 is defined as Rd3.

The third switch 280 is a component that starts or ends the sampling phase.

One end of the third switch 280 is connected to the output terminal of the sampling phase unit 200, and the other end is grounded. The third switch 280 is connected in parallel to the third distribution resistor 270.

In order for the insulation resistance measuring unit 500 to measure the positive insulation resistance 210 and negative insulation resistance 220 of the battery 100, the current connected to the positive electrode of the battery 100, ground, and the negative electrode of the battery 100 You need to create a path. To this end, the first switch 240 and the second switch 260 are turned on/off to create a current path.

To measure the sampling voltage (Vd) of the anode insulation resistance 210, the first switch 240 is turned off and the second switch 260 is turned on. At this time, in normal cases, the anode insulation resistance 210 has an infinite value, so no current flows. In contrast, when insulation breakdown occurs, the current flows in the following order: battery (100) - anode insulation resistance (210) - third distribution resistor (270) - second switch (260) - second distribution resistor (250) - battery (100) It flows.

The sampling voltage (Vd) of the anode insulation resistance 210 is based on the voltage distribution principle, and its size is as follows.

To measure the sampling voltage (Vd) of the cathode insulation resistance 220, the first switch 240 is turned on and the second switch 260 is turned off. At this time, in the normal case, the cathode insulation resistance 220 is infinite, so no current flows. In contrast, when insulation breakdown occurs, the current flows in the following order: battery 100 - first distribution resistor 230 - first switch 240 - third distribution resistor 270 - negative insulation resistance 220 - battery 100. It flows.

The sampling voltage (Vd) of the cathode insulation resistance 220 is based on the voltage distribution principle, and its size is as follows.

The first switch 240 is disposed between the first distribution resistor 230 and the third distribution resistor 270. The second switch 260 is disposed between the second distribution resistor 250 and the third distribution resistor 270. By having this arrangement, the switch can be protected from external surges, thereby extending the life of the device.

The third switch 280 determines the end of the sampling phase and the start of the amplification phase. Specifically, the third switch 280 is turned off in the sampling phase and turned on in the amplification phase.

In the sampling phase, the third switch 280 is turned off. At this time, the third distribution resistor 270 and the input capacitor 320 are arranged in parallel, and the voltage value charged to the input capacitor 320 is Vd.

In the amplification phase, the third switch 280 is turned on. Accordingly, the output terminal of the sampling phase unit 200 is grounded, and the sampling phase unit 200 and the amplification phase unit 300 are electrically separated.

The amplification phase unit 300 is a component that amplifies the sampling voltage (Vd) and outputs the amplification voltage (Va) when the sampling voltage (Vd) is applied.

The amplification phase unit 300 is connected to the output terminal of the sampling phase unit 200 and includes at least one capacitor.

The input terminal of the amplification phase unit 300 is connected to the output terminal of the sampling phase unit 200, and the output terminal of the amplification phase unit 300 is connected to the insulation resistance measurement unit 500.

When the inverting amplifier unit 400 is not provided, the output terminal of the amplification phase unit 300 is connected to the input terminal of the insulation resistance measurement unit 500. In contrast, when the inverting amplifier unit 400 is provided, the output terminal of the amplification phase unit 300 is connected to the input terminal of the insulation resistance measurement unit 500.

The amplification phase unit 300 includes a first operational amplifier 310, an input capacitor 320, an output capacitor 330, a fourth switch 340, and a fifth switch 350.

An operational amplifier is a high-gain direct current amplifier that has arithmetic functions such as addition or integration depending on the negative feedback method. The first operational amplifier 310 is generally well known, and detailed description will be omitted.

The first operational amplifier 310 is disposed in the amplification phase unit 300. The input terminal of the first operational amplifier 310 constitutes the input terminal of the amplification phase unit 300, and specifically, the cathode of the first operational amplifier 310 becomes the input terminal of the amplification phase unit 300. The output terminal of the first combination amplifier constitutes the output terminal of the amplification phase unit 300.

A voltage having a magnitude of Vdd/2 is supplied to the first operational amplifier 310. That is, the maximum value of the voltage output from the first operational amplifier 310 does not exceed Vdd/2.

The input capacitor 320 is a component that temporarily stores the sampling voltage (Vd).

One end of the input capacitor 320 is connected to the output terminal of the sampling phase unit 200, and the other end is connected to the input terminal of the first operational amplifier 310.

The capacity of the input capacitor 320 is defined as Cin.

The output capacitor 330 is a component that amplifies the sampling voltage (Vd) in conjunction with the input capacitor 320.

One end of the output capacitor 330 is connected to the input terminal of the first operational amplifier 310, and the other end is connected to the output terminal of the first operational amplifier 310.

The capacity of the output capacitor 330 is defined as Cf.

The fourth switch 340 is a component that starts the operation of the amplification phase unit 300 together with the fifth switch 350.

The fourth switch 340 has one end connected to the input terminal of the first operational amplifier 310, the other end connected to the output terminal of the first operational amplifier 310, and is arranged in parallel with the output capacitor 330.

The fifth switch 350 is a component that starts the operation of the amplification phase unit 300 together with the fourth switch 340.

One end of the fifth switch 350 is connected to the output terminal of the first operational amplifier 310, and the other end is grounded.

The fourth switch 340 and the fifth switch 350 determine the start of the amplification phase. Specifically, the fourth switch 340 and the fifth switch 350 are turned on in the sampling phase and turned off in the amplification phase.

In the sampling phase, the fourth switch 340 and the fifth switch 350 are turned on. At this time, both the cathode and the output terminal of the first operational amplifier 310 are grounded, so the output capacitor 330 is not charged.

In the amplification phase, the fourth switch 340 and the fifth switch 350 are turned off. At this time, the charge charged in the input capacitor 320 is transferred to the output capacitor 330. The voltage value of the output capacitor 330 follows the law of charge conservation and is as follows.

In general RC circuits, the steady state is generally set at 5 times the time constant. Therefore, for repeated operation, the switch can be changed again after a time of at least 5 times the time constant has elapsed, resulting in poor responsiveness. However, in the amplification phase unit 300 according to the present invention, charges are moved instantaneously according to the law of conservation of charge, so a time condition equal to 5 times the time constant is not necessary. Therefore, there is an effect of faster response.

In particular, the prior literature did not adopt an operational amplifier to improve responsiveness, but consisted of a resistor-only circuit. In this case, since the leaked voltage value cannot be amplified, there is a problem in that measurement is difficult when the leaked voltage value is low. However, the amplification phase unit 300 according to the present invention has the effect of improving responsiveness and amplifying leakage voltage values at the same time, making it possible to easily measure low leakage voltage values.

The inverting amplifier unit 400 is a component that transmits the output voltage (Vo) of which the polarity and size of the amplification voltage (Va) have been changed to the insulation resistance measuring unit (500).

The inverting amplifier unit 400 is disposed between the amplification phase unit 300 and the insulation resistance measurement unit 500, includes a plurality of amplification resistors, and adjusts the output voltage (Vo) to the insulation resistance in proportion to the amplification voltage (Va). It is transmitted to the measuring unit 500.

The inverting amplifier 400 includes a second operational amplifier 410 and first to fourth amplification resistors 420 to 450.

The second operational amplifier 410 is disposed in the inverting amplifier 400. The input terminal of the second operational amplifier 410 constitutes the input terminal of the inverting amplifier 400, and specifically, the cathode of the second operational amplifier 410 becomes the input terminal of the inverting amplifier 400. The output terminal of the second combination amplifier constitutes the output terminal of the inverting amplifier 400.

A voltage having a magnitude of Vdd is supplied to the second operational amplifier 410. That is, the maximum value of the voltage output from the second operational amplifier 410 does not exceed Vdd.

When the amplification voltage (Va) is input, the inverting amplifier 400 amplifies the amplification voltage (Va) according to the relationship below and outputs the output voltage (Vo).

The inverting amplifier 400 amplifies the voltage value and changes the polarity at the same time.

As the first operational amplifier 310 is disposed inside the amplification phase unit 300, the input and output values of the amplification phase unit 300 have opposite polarities. Therefore, by arranging the inverting amplifier 400, the sampling voltage (Vd) and the output voltage (Vo) have the same polarity.

In addition, the inverting amplifier 400 amplifies the amplification voltage (Va) once more, thereby amplifying the sampling voltage (Vd) in two stages, which has the effect of measuring a lower leakage voltage.

The insulation resistance measuring unit 500 is a component that measures the insulation resistance of the battery 100 using the output voltage.

The insulation resistance measurement unit 500 is connected to the output terminal of the amplification phase unit 300 and measures the output voltage (Vo) relative to the amplification voltage (Va).

When the inverting amplifier unit 400 is not provided, the input terminal of the insulation resistance measurement unit 500 is connected to the output terminal of the amplification phase unit 300. In contrast, when the inverting amplifier 400 is provided, the input terminal of the insulation resistance measurement unit 500 is connected to the output terminal of the inverting amplifier 400.

Meanwhile, the insulation resistance measurement unit 500 measures the cathode insulation resistance 220 of the battery 100 using the voltage applied to the first distribution resistance 230, and measures the second distribution resistance 250 as described later. The anode insulation resistance 210 of the battery 100 is measured using the voltage applied to the battery 100.

In order to perform operations such as measuring the voltage applied to the distribution resistance, measuring the insulation resistance of the battery 100 using the measured voltage, and controlling the switch to create a current path, the insulation resistance measurement unit 500 is a microcontroller unit. (Micro Controller Unit; MCU) may be included.

Figure 7 is a diagram showing the voltage value measured by the insulation resistance measuring unit 500 according to the present invention.

Vold and Vohd are reference values already stored in the storage unit. The insulation resistance measuring unit 500 determines whether the insulation resistance is destroyed by comparing the measured voltage value with Vold or Vohd.

For example, if the measured voltage value is lower than Vohd, it may be determined that the anode insulation resistance 210 is destroyed. Alternatively, if the measured voltage value is higher than Vold, it may be determined that the cathode insulation resistance 220 is destroyed.

Below, the insulation resistance measurement method will be described.

The sampling phase (S10) is a step of outputting the sampling voltage (Vd) and is performed in the sampling phase unit 200. Specifically, when the battery voltage (Vb) is applied from the battery 100, the sampling voltage (Vd) is output according to the voltage distribution principle.

In the step of outputting the sampling voltage (Vd), either the first switch 240 or the second switch 260 is alternatively turned on and the other is turned off.

The third switch 280 is turned off in the step of outputting the sampling voltage (Vd) and turned on in the step of outputting the amplification voltage (Va).

Specifically, referring to FIG. 3, in order to measure the anode insulation resistance 210, the first switch 240 is turned off, the second switch 260 is turned on, the third switch 280 is turned off, and the first switch 240 is turned off. The fourth switch 340 and the fifth switch 350 are turned on. Or, referring to FIG. 5, in order to measure the cathode insulation resistance 220, the first switch 240 is turned on, the second switch 260 is turned off, the third switch 280 is turned off, and the first switch 240 is turned on. The fourth switch 340 and the fifth switch 350 are turned on.

To measure the anode insulation resistance 210, the first switch 240 is turned off and the second switch 260 is turned on, so that current flows as shown in FIG. 3. Alternatively, to measure the cathode insulation resistance 220, the first switch 240 is turned on and the second switch 260 is turned off, so that current flows as shown in FIG. 5.

The third switch 280 is turned off, and a voltage of Vd is applied to the third distribution resistor 270, and the input capacitor 320 is charged, and the voltage is Vd.

The fourth switch 340 and the fifth switch 350 are turned on, and the output capacitor 330 is not charged.

The amplification phase (S20) is a step of generating an amplification voltage (Va) and is performed in the amplification phase unit 300. Specifically, when the sampling voltage (Vd) is applied, the sampling voltage (Vd) is amplified according to the law of conservation of charge to generate the amplification voltage (Va).

4 and 6, the first switch 240 and the second switch 260 are turned off, the third switch 280 is turned on, and the fourth switch 340 and the fifth switch 350 are turned on. It turns off.

The third switch 280 is turned on, and the sampling phase unit 200 and the amplification phase unit 300 are electrically separated. Furthermore, in order to eliminate the influence of the sampling phase unit 200 on the amplification phase unit 300, the first switch 240 and the second switch 260 may be turned off.

The fourth switch 340 and the fifth switch 350 are turned off, and the charge charged in the input capacitor 320 is transferred to the output capacitor 330. At this time, according to the law of conservation of charge, the output capacitor 330 is charged with a voltage of Va.

An inversion amplifier 400 may be disposed between the amplification phase unit 300 and the insulation resistance measurement unit 500. The inverting amplifier 400 can change the polarity of the amplification voltage (Va) and further amplify its size. Accordingly, the polarity of the output voltage (Vo) and the sampling voltage (Vd) becomes the same.

The step S30 of measuring the output voltage (Vo) is performed in the insulation resistance measuring unit 500, and measures the output voltage (Vo) related to the amplification voltage (Va).

Thereafter, the control unit or the insulation resistance measurement unit 500 compares the output voltage (Vo) with a previously stored reference value (S40).

For example, if the output value measured according to FIGS. 3 and 4 is less than Vohd, it is determined that the anode insulation resistance 210 is destroyed. Alternatively, when the output value measured according to FIGS. 5 and 6 is greater than Vold, it is determined that the cathode insulation resistance 220 is destroyed.

If the control unit or the insulation resistance measurement unit 500 determines that the insulation resistance has been destroyed, it may notify the user of this.

In the above, preferred embodiments of the present invention have been shown and described, but the present invention is not limited to the specific embodiments described above, and can be used in the technical field to which the invention pertains without departing from the gist of the present invention as claimed in the patent claims. Of course, various modifications can be made by those skilled in the art, and these modifications should not be understood individually from the technical idea or perspective of the present invention.

100: battery
200: Sampling phase part
210: anode insulation resistance 220: cathode insulation resistance
230: first distribution resistor 240: first switch
250: second distribution resistor 260: second switch
270: Third distribution resistor 280: Third switch
300: Amplification phase part
310: first operational amplifier 320: input capacitor
330: output capacitor 340: fourth switch
350: 5th switch
400: Inversion amplification unit
410: second operational amplifier 420: first amplification resistor
430: Second amplification resistor 440: Third amplification resistor
450: Fourth amplification resistor
500: Insulation resistance measurement unit

Claims (13)

a sampling phase unit whose input terminal is connected to a battery, includes at least one insulation resistor, includes at least one distribution resistor, and outputs a sampling voltage when a battery voltage is applied from the battery;
an amplification phase unit connected to the output terminal of the sampling phase unit, including at least one capacitor, and amplifying the sampling voltage when the sampling voltage is applied to output an amplified voltage;
an insulation resistance measurement unit connected to the output terminal of the amplification phase unit, measuring an output voltage relative to the amplification voltage, and measuring insulation resistance of the battery using the output voltage; and
An inverting amplifier disposed between the amplification phase unit and the insulation resistance measurement unit, includes a plurality of amplification resistors, and transmits an output voltage to the insulation resistance measurement unit in proportion to the amplification voltage.
Including,
The sampling phase unit,
As a component for starting or ending the sampling phase stage, it has a third switch whose one end is connected to the output terminal of the sampling phase unit and the other end is grounded,
The amplification phase unit,
A first operational amplifier as a high-gain direct current amplifier with an operation function according to the negative feedback method; and
A fourth switch, which is a component that initiates the operation of the amplification phase unit, has one end connected to the input terminal of the first operational amplifier and the other end connected to the output terminal of the first operational amplifier.
Equipped with
The inverting amplifier,
An insulation resistance measuring device including a second operational amplifier whose cathode becomes the input terminal of the inverting amplifier, and whose output terminal becomes the output terminal of the inverting amplifier. According to paragraph 1,
The sampling phase unit,
A positive insulation resistor, one end of which is connected to the positive electrode of the battery and the other end of which is grounded;
a first distribution resistor, one end of which is connected to the anode of the battery and disposed in parallel with the anode insulation resistor;
Negative insulation resistance, one end of which is connected to the negative electrode of the battery and the other end of which is grounded.
An insulation resistance measuring device comprising a second distribution resistor, one end of which is connected to the negative electrode of the battery, and a second distribution resistor disposed in parallel with the negative electrode insulation resistance. According to paragraph 1,
The sampling phase unit,
a first distribution resistor whose end is connected to the positive electrode of the battery;
a first switch whose one end is connected to the first distribution resistor and the other end of which is connected to the output terminal of the sampling phase unit;
a second distribution resistor, one end of which is connected to the negative electrode of the battery;
Insulation resistance measurement device including a second switch, one end of which is connected to the second distribution resistor and the other end of which is connected to the output terminal of the sampling phase unit. According to paragraph 1,
The sampling phase unit,
a first distribution resistor having one end connected to the positive electrode of the battery and the other end connected to the output terminal of the sampling phase unit;
a second distribution resistor with one end connected to the negative electrode of the battery and the other end connected to the output terminal of the sampling phase unit;
An insulation resistance measuring device comprising a third distribution resistor, one end of which is connected to the output terminal of the sampling phase unit, and the other end of which is grounded. delete According to paragraph 1,
The amplification phase unit,
first operational amplifier;
an input capacitor with one end connected to the output terminal of the sampling phase unit and the other end connected to the input terminal of the first operational amplifier;
An output capacitor whose one end is connected to the input terminal of the first operational amplifier and the other end is connected to the output terminal of the first operational amplifier. According to clause 6,
The amplification phase unit,
The fourth switch has one end connected to the input terminal of the first operational amplifier, the other end connected to the output terminal of the first operational amplifier, and arranged in parallel with the output capacitor;
An insulation resistance measuring device comprising a fifth switch, one end of which is connected to the output terminal of the first operational amplifier, and the other end of which is grounded.
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