Voltage measuring device and system

Abstract

The utility model discloses a voltage measuring device and system, relates to the field of testing, and aims to solve the problem that the accuracy of charging and discharging testing of a lithium battery is influenced due to the fact that voltage drop possibly exists at the two ends of an existing lithium battery testing power supply, so that a controller, a direct-current adjustable voltage stabilizing module and a voltage measuring device are arranged in the voltage measuring device. The controller controls the to-be-tested power supply to be put into the loop where the DC adjustable voltage stabilization module is located so as to automatically measure the voltage drop of the to-be-tested power supply, the voltage drop of the to-be-tested power supply does not need to be repeatedly measured by manpower and material resources, and the voltage value output by the DC adjustable voltage stabilization module is always kept stable. Therefore, the first voltage value when the to-be-tested power supply is not switched on and the second voltage value after the to-be-tested power supply is switched on can be accurately measured, so that the controller can calibrate the to-be-tested power supply according to the first voltage value and the second voltage value so as to eliminate the voltage drop at the two ends of the to-be-tested power supply, thereby ensuring the accuracy of the charging and discharging test of the lithium battery.

Description

Technical Field

[0001] This utility model relates to the field of testing, and in particular to a voltage measuring device and system. Background Technology

[0002] During the hot-pressing formation and capacity grading of lithium batteries, a test power supply needs to be connected between the positive and negative terminals of each lithium battery. This involves applying a large current between the positive and negative terminals of each lithium battery for charge and discharge testing. By charging and discharging the lithium battery cells, data such as capacity and internal resistance can be analyzed to determine the quality grade of the lithium battery cells. Cells of the same quality grade are then grouped for series or parallel connection. However, if there is a voltage drop in the test power supply, it will lead to errors in the test results of the lithium battery cells. Current methods for measuring the voltage drop of the test power supply require operators to manually measure it with external equipment. Furthermore, to ensure the accuracy of the lithium battery charge and discharge test, the voltage drop measurement of the test power supply needs to be repeated multiple times. Therefore, this method consumes a lot of manpower and resources. Utility Model Content

[0003] The purpose of this invention is to provide a voltage measurement device and system. This solution automatically measures the voltage drop of the power supply under test by controlling the power supply under test to be connected to the circuit of the DC adjustable voltage regulator module through a controller. This eliminates the need for repeated measurement of the voltage drop of the power supply under test using manpower and resources. Moreover, the voltage value output by the DC adjustable voltage regulator module remains stable, so it can accurately measure the first voltage value when the power supply under test is not connected and the second voltage value after the power supply under test is connected. This allows the controller to calibrate the power supply under test based on the magnitude of the first and second voltage values, thereby eliminating the voltage drop across the power supply under test and ensuring the accuracy of lithium battery charge and discharge testing.

[0004] To solve the above-mentioned technical problems, this utility model provides a voltage measuring device, including: a controller, a DC adjustable voltage regulator module, and a voltage measuring device;

[0005] The controller is connected to the control terminal of the DC adjustable voltage regulator module, and the receiving terminal is connected to the output terminal of the voltage measuring device, for outputting a standard voltage to the DC adjustable voltage regulator module;

[0006] The output terminal of the DC adjustable voltage regulator module is connected to the first terminal of the power supply under test, and is used to output the stable voltage converted from the standard voltage.

[0007] The second terminal of the power supply under test is grounded;

[0008] The first end of the voltage measuring device is connected to the DC adjustable voltage regulator module, and the second end is connected to the ground wire. It is used to transmit the first voltage value when the power supply under test is not turned on and the second voltage value after the power supply under test is turned on to the controller.

[0009] Optionally, the DC adjustable voltage regulator module includes: a Zener diode, a first operational amplifier, a first resistor, a second resistor, a third resistor, and a first power electronic device;

[0010] The first end of the first resistor is connected to the first DC power supply and the first end of the first power electronic device, respectively.

[0011] The non-inverting input terminal of the first operational amplifier is connected to the second terminal of the first resistor and the cathode of the Zener diode, the negative-inverting input terminal is connected to the first terminal of the first resistor and the first terminal of the second resistor, and the output terminal is connected to the control terminal of the first power electronic device.

[0012] The second terminal of the first power electronic device is connected to the second terminal of the first resistor, the first terminal of the power supply under test, and the first terminal of the voltage measuring device, respectively. The first power electronic device operates in the linear amplification region.

[0013] The anode of the voltage regulator is connected to ground;

[0014] The second terminal of the second resistor is grounded.

[0015] Optionally, the DC adjustable voltage regulator module includes: a DAC chip, a second operational amplifier, a fourth resistor, a fifth resistor, and a second power electronic device;

[0016] The control terminal of the DAC chip is connected to the controller and is used to output a corresponding DC voltage value based on the control of the controller.

[0017] The non-inverting input terminal of the second operational amplifier is connected to the DAC chip, the negative-inverting input terminal is connected to the first terminal of the fourth resistor and the first terminal of the fifth resistor respectively, and the output terminal is connected to the control terminal of the second power electronic device.

[0018] The first end of the second power electronic device is connected to the first DC power supply, and the second end is connected to the second end of the fourth resistor, the first end of the power supply under test, and the first end of the voltage measuring device. The second power electronic device operates in the linear amplification region.

[0019] The second terminal of the fifth resistor is grounded.

[0020] Optionally, the DC adjustable voltage regulator module further includes:

[0021] The filtering module has its first end connected to the second end of the second power electronic device, the second end of the fourth resistor, the first end of the power supply under test, and the first end of the voltage measuring device, respectively, and its second end connected to the negative input terminal of the second operational amplifier, the first end of the fourth resistor, and the first end of the fifth resistor, respectively.

[0022] Optionally, the second power electronic device is an NPN transistor, wherein the base of the NPN transistor is the control terminal of the second power electronic device, the collector of the NPN transistor is the first terminal of the second power electronic device, and the emitter of the NPN transistor is the second terminal of the second power electronic device.

[0023] Optionally, the second power electronic device is an N-type MOSFET, the gate of the N-type MOSFET is the control terminal of the second power electronic device, the drain of the N-type MOSFET is the first terminal of the second power electronic device, and the source of the N-type MOSFET is the second terminal of the second power electronic device.

[0024] Optionally, the DC adjustable voltage regulator module includes: a switching module and several second DC power supplies with different output voltages;

[0025] The switching module has several first terminals connected to each of the second DC power supplies with different output voltages, and its second terminals connected to the first terminals of the power supply under test and the voltage measuring device, respectively. The control terminal is connected to the controller and is used to select any one of the first terminals of the switching module to be connected to the second terminal of the switching module based on the control of the controller.

[0026] Optionally, the adjustable DC voltage regulator module is a DC-DC converter. The input terminal of the DC-DC converter is connected to a third DC power supply, the output terminal is connected to the first terminal of the power supply under test and the first terminal of the voltage measuring device, and the control terminal is connected to the controller for adjusting the duty cycle of the internal switching transistor of the DC-DC converter based on the control of the controller, so that the DC-DC converter outputs the corresponding test voltage value.

[0027] Optional, also includes:

[0028] A protection device, wherein the first end of the protection device is connected to the DC adjustable voltage regulator module, and the second end is connected to the first end of the power supply under test and the first end of the voltage measuring device, respectively, for disconnecting when an overvoltage and / or overcurrent occurs in the circuit where the DC adjustable voltage regulator module is located.

[0029] To solve the above-mentioned technical problems, this utility model also provides a voltage measurement system, including: a power supply under test and a voltage measuring device as described above, wherein the voltage measuring device is connected to the power supply under test.

[0030] The purpose of this invention is to provide a voltage measuring device and system. Considering that there may be a voltage drop across the terminals of existing lithium battery test power supplies, which affects the accuracy of lithium battery charge and discharge tests, this solution incorporates a controller, a DC adjustable voltage regulator module, and voltage measuring devices within the voltage measuring device. The controller controls the power supply under test to be connected to the circuit of the DC adjustable voltage regulator module, thereby automatically measuring the voltage drop of the power supply under test. This eliminates the need for repeated manual and material measurements of the voltage drop of the test power supply. Furthermore, the voltage value output by the DC adjustable voltage regulator module remains stable, thus accurately measuring the first voltage value when the power supply under test is not connected and the second voltage value after the power supply under test is connected. The controller can then calibrate the power supply under test based on the magnitude of the first and second voltage values ​​to eliminate the voltage drop across the power supply under test, thereby ensuring the accuracy of lithium battery charge and discharge tests. Attached Figure Description

[0031] To more clearly illustrate the technical solutions in the embodiments of this utility model or the prior art, the drawings used in the description of the embodiments or the prior art will be briefly introduced below. Obviously, the drawings described below are only embodiments of this utility model. For those skilled in the art, other drawings can be obtained based on the provided drawings without creative effort.

[0032] Figure 1 A schematic diagram of the structure of a voltage measuring device provided by this utility model;

[0033] Figure 2 This is a schematic diagram of another voltage measuring device provided by this utility model. Detailed Implementation

[0034] The core of this invention is to provide a voltage measurement device and system. This solution automatically measures the voltage drop of the power supply under test by controlling the power supply under test to be connected to the circuit of the DC adjustable voltage regulator module through a controller. This eliminates the need for repeated measurement of the voltage drop of the power supply under test using manpower and resources. Moreover, the voltage value output by the DC adjustable voltage regulator module remains stable, so it can accurately measure the first voltage value when the power supply under test is not connected and the second voltage value after the power supply under test is connected. This allows the controller to calibrate the power supply under test based on the magnitude of the first and second voltage values, thereby eliminating the voltage drop across the power supply under test and ensuring the accuracy of lithium battery charge and discharge testing.

[0035] To make the objectives, technical solutions, and advantages of the embodiments of this utility model clearer, the technical solutions of the embodiments of this utility model will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some embodiments of this utility model, not all embodiments. Based on the embodiments of this utility model, all other embodiments obtained by those skilled in the art without creative effort are within the protection scope of this utility model.

[0036] Please refer to Figure 1 , Figure 1 This is a schematic diagram of a voltage measuring device provided by the present invention. The voltage measuring device includes: a controller 1, a DC adjustable voltage regulator module 2, and a voltage measuring device 3;

[0037] The operational amplifier controller 1 is connected to the control terminal of the operational amplifier DC adjustable voltage regulator module 2, and the receiving terminal is connected to the output terminal of the operational amplifier voltage measuring device 3, which is used to output a standard voltage to the operational amplifier DC adjustable voltage regulator module 2.

[0038] The output terminal of the operational amplifier DC adjustable voltage regulator module 2 is connected to the first terminal of the power supply under test, and is used to output a stable voltage converted from the standard voltage of the operational amplifier;

[0039] The second terminal of the operational amplifier's power supply under test is grounded;

[0040] The first end of the operational amplifier voltage measuring device 3 is connected to the operational amplifier DC adjustable voltage regulator module 2, and the second end is connected to the ground wire. It is used to transmit the measured first voltage value of the operational amplifier when the power supply under test is not turned on and the second voltage value of the operational amplifier after the power supply under test is turned on to the operational amplifier controller 1.

[0041] In this invention, considering that there may be a voltage drop across the terminals of existing lithium battery test power supplies, which affects the accuracy of lithium battery charge and discharge tests, and that existing voltage drop testing methods require a lot of manpower and resources, this solution incorporates a controller 1, a DC adjustable voltage regulator module 2, and a voltage measuring device 3 within the voltage measuring device. The controller 1 controls the power supply under test to be connected to the circuit of the DC adjustable voltage regulator module 2, thereby automatically measuring the voltage drop of the power supply under test. This eliminates the need for repeated measurement of the voltage drop of the test power supply using manpower and resources. Moreover, the voltage value output by the DC adjustable voltage regulator module 2 remains stable, thus ensuring the accuracy of the first and second voltage values. This allows the controller 1 to calibrate the power supply under test based on the magnitude of the first and second voltage values, eliminating the voltage drop across the power supply under test and ensuring the accuracy of lithium battery charge and discharge tests.

[0042] It should be noted that in practical applications, only the output voltage value of the DC adjustable voltage regulator module 2 needs to be controlled to calibrate the voltage drop of multiple power supplies under test at the same time, thereby greatly shortening the calibration time of voltage drop while ensuring calibration accuracy.

[0043] This embodiment provides a voltage measurement device. Considering that there may be a voltage drop across the terminals of existing lithium battery test power supplies, which may affect the accuracy of lithium battery charge and discharge tests, this solution includes a controller 1, a DC adjustable voltage regulator module 2, and a voltage measuring device 3 within the voltage measurement device. The controller 1 controls the power supply under test to be connected to the circuit of the DC adjustable voltage regulator module 2, thereby automatically measuring the voltage drop of the power supply under test. This eliminates the need for repeated manual and material measurements of the voltage drop of the test power supply. Moreover, the voltage value output by the DC adjustable voltage regulator module 2 remains stable, thus accurately measuring the first voltage value when the power supply under test is not connected and the second voltage value after the power supply under test is connected. This allows the controller 1 to calibrate the power supply under test based on the magnitude of the first and second voltage values, thereby eliminating the voltage drop across the power supply under test and ensuring the accuracy of lithium battery charge and discharge tests.

[0044] Based on the above embodiments:

[0045] As an optional embodiment, the operational amplifier DC adjustable voltage regulator module 2 includes: a Zener diode, a first operational amplifier, a first resistor, a second resistor, a third resistor, and a first power electronic device;

[0046] The first terminal of the first resistor of the operational amplifier is connected to the first DC power supply and the first terminal of the first power electronic device of the operational amplifier, respectively.

[0047] The non-inverting input terminal of the first operational amplifier is connected to the second terminal of the first operational amplifier resistor and the cathode of the operational amplifier Zener diode, respectively; the negative-inverting input terminal is connected to the first terminal of the first operational amplifier resistor and the first terminal of the second operational amplifier resistor, respectively; and the output terminal is connected to the control terminal of the first operational amplifier power electronic device.

[0048] The second terminal of the first power electronic device of the operational amplifier is connected to the second terminal of the first resistor of the operational amplifier, the first terminal of the power supply under test of the operational amplifier, and the first terminal of the voltage measuring device 3 of the operational amplifier, respectively. The first power electronic device of the operational amplifier operates in the linear amplification region.

[0049] The anode of the operational amplifier's Zener diode is connected to ground;

[0050] The second terminal of the second resistor in the operational amplifier is grounded.

[0051] In this invention, to ensure the stability and adjustability of the output voltage of the DC adjustable voltage regulator module 2, an operational amplifier circuit consisting of a first operational amplifier, a second resistor, and a third resistor, a Zener diode, and a first power electronic device are provided. The output voltage of the DC adjustable voltage regulator module 2 can be adjusted by simply adjusting the resistance values ​​of the second and third resistors. The Zener diode is located at the non-inverting input terminal of the first operational amplifier, so it can stabilize the voltage at a preset value even if the input voltage of the first DC power supply changes. This ensures the stability of the voltage at the non-inverting input of the operational amplifier. Furthermore, the most critical component is the first power electronic device. When the output voltage of the first operational amplifier decreases, because the first power electronic device operates in the linear amplification region, its output current also decreases. According to Ohm's law, this leads to a decrease in the load voltage. Similarly, when the output voltage of the first operational amplifier decreases, the voltage at the negative input is lower than that at the non-inverting input, causing the output voltage of the first operational amplifier to increase. Since the first power electronic device operates in the linear amplification region, its current also increases when the output voltage of the first operational amplifier increases, leading to an increase in the load voltage. This ensures the stability of the output voltage of the DC adjustable voltage regulator module 2.

[0052] As an optional embodiment, the operational amplifier DC adjustable voltage regulator module 2 includes: a DAC chip, a second operational amplifier, a fourth resistor, a fifth resistor, and a second power electronic device;

[0053] The control terminal of the operational amplifier DAC chip is connected to the operational amplifier controller 1, and is used to output the corresponding DC voltage value based on the control output of the operational amplifier controller 1.

[0054] The non-inverting input terminal of the second operational amplifier is connected to the operational amplifier DAC chip, the negative-inverting input terminal is connected to the first terminal of the fourth resistor and the first terminal of the fifth resistor of the operational amplifier, and the output terminal is connected to the control terminal of the second power electronic device of the operational amplifier.

[0055] The first terminal of the second power electronic device of the operational amplifier is connected to the first DC power supply, and the second terminal is connected to the second terminal of the fourth resistor of the operational amplifier, the first terminal of the power supply under test of the operational amplifier, and the first terminal of the voltage measuring device 3 of the operational amplifier. The second power electronic device of the operational amplifier operates in the linear amplification region.

[0056] The second terminal of the fifth resistor in the operational amplifier is grounded.

[0057] In this invention, to ensure the stability and adjustability of the output voltage of the DC adjustable voltage regulator module 2, an operational amplifier circuit consisting of a second operational amplifier, a fourth resistor, and a fifth resistor, a DAC (Digital to Analog Converter) chip, and a second power electronic device are provided. The output voltage of the DC adjustable voltage regulator module 2 can be adjusted simply by changing the values ​​of the fourth and fifth resistors. The DAC chip is located at the non-inverting input of the second operational amplifier, and its output voltage is guaranteed to remain stable, thus ensuring the stability of the voltage at the non-inverting input of the operational amplifier. Furthermore, the most critical component is the second power electronic device. When the output voltage of the second operational amplifier decreases, since the second power electronic device operates in the linear amplification region, its output current also decreases. According to Ohm's law, this leads to a decrease in load voltage. Similarly, when the output voltage of the second operational amplifier decreases, the voltage at the negative input terminal of the second operational amplifier is lower than that at the positive input terminal. At this time, the output voltage of the second operational amplifier increases. Since the second power electronic device operates in the linear amplification region, its current also increases when the output voltage of the second operational amplifier increases. This leads to an increase in load voltage, thereby stabilizing the output voltage of the DC adjustable voltage regulator module 2.

[0058] It should also be noted that, such as Figure 2 As shown, taking a voltage measurement device composed of a DAC chip as an example, the controller 1 communicates with the DAC chip using SPI (Serial Peripheral Interface) to control the output voltage value of the DAC chip; the controller 1 communicates with the multimeter (voltage measuring device 3) via Ethernet to read the voltage data measured by the multimeter; in addition, the controller 1 also communicates with the intermediate computer via RS485 to receive relevant calibration instructions issued by the intermediate computer; the DAC chip receives the instructions from the controller 1 and outputs a specified voltage; the second operational amplifier, the second power electronic device, the filter capacitor, the fourth resistor, and the fifth resistor form a DC adjustable linear voltage regulator module, which adjusts the voltage output by the DAC chip to the preset value -VOUT through the circuit (the output voltage of the DAC chip can be amplified by adjusting the resistance values ​​of the fourth and fifth resistors); the multimeter transmits the measured voltage value to the controller 1 via Ethernet.

[0059] It should also be noted that the voltage measurement device provided in this solution can perform two processes: power-on self-calibration and voltage calibration. Specifically, 1. Power-on self-calibration: After power-on, controller 1 controls the DAC chip to output several voltage values ​​within the range of 0~5V as calibration points. By comparing the output voltage value with the voltage value collected by the multimeter, the output voltage value is calibrated and corrected. Ultimately, an output accuracy of 0~5V ±1mV can be achieved.

[0060] 2. Voltage Calibration: After receiving the command from the intermediate computer, the controller 1 switches the power supply under test to the output of the DC adjustable voltage regulator module 2. The controller 1 controls the DAC chip to output the relevant calibration voltage value. The voltage value sent by the intermediate computer (i.e., the sent value), the voltage value collected by the multimeter (i.e., the collected value), and the voltage value collected by the power supply under test are compared pairwise. When the error of all comparison results is ≤0.5%, it is judged as qualified. Otherwise, the relevant data will be uploaded to the intermediate computer to calibrate the power supply under test until the above error meets the qualification requirements.

[0061] As an optional embodiment, the operational amplifier DC adjustable voltage regulator module 2 further includes:

[0062] The first terminal of the operational amplifier filter module is connected to the second terminal of the second power electronic device of the operational amplifier, the second terminal of the fourth resistor of the operational amplifier, the first terminal of the power supply under test of the operational amplifier, and the first terminal of the voltage measuring device 3 of the operational amplifier, respectively. The second terminal is connected to the negative phase input terminal of the second operational amplifier, the first terminal of the fourth resistor of the operational amplifier, and the first terminal of the fifth resistor of the operational amplifier, respectively.

[0063] In this invention, considering that the DC adjustable voltage regulator module 2 may be affected by environmental factors when transmitting voltage to the power supply under test, resulting in unstable output voltage and ultimately affecting the accuracy of voltage drop determination and calibration, this solution adds a filter module inside the operational amplifier composed of the second operational amplifier, the fourth resistor, and the fifth resistor. The filter module filters out interference caused by environmental factors to ensure the stability of the output voltage of the DC adjustable voltage regulator module 2.

[0064] As an optional embodiment, the second power electronic device of the operational amplifier is an NPN transistor, the base of the operational amplifier NPN transistor is the control terminal of the operational amplifier second power electronic device, the collector of the operational amplifier NPN transistor is the first terminal of the operational amplifier second power electronic device, and the emitter of the operational amplifier NPN transistor is the second terminal of the operational amplifier second power electronic device.

[0065] In this invention, considering the advantages of transistors such as long lifespan, high durability, stability and reliability, ease of automation, and low cost, an NPN transistor is selected as the second power electronic device.

[0066] As an optional embodiment, the second power electronic device of the operational amplifier is an N-type MOS transistor. The gate of the N-type MOS transistor is the control terminal of the operational amplifier, the drain of the N-type MOS transistor is the first terminal of the operational amplifier, and the source of the N-type MOS transistor is the second terminal of the operational amplifier.

[0067] In this invention, considering that MOSFETs have advantages such as high input resistance, low noise, low power consumption, easy integration, and wide safe operating area, this solution selects an N-type MOSFET (Metal-Oxide-Semiconductor Field-Effect Transistor) as the second power electronic device.

[0068] As an optional embodiment, the operational amplifier DC adjustable voltage regulator module 2 includes: a switching module and several second DC power supplies with different output voltages;

[0069] The first terminals of the operational amplifier switching module are connected one-to-one with the second DC power supply with different output voltages of each operational amplifier. The second terminals are connected to the first terminal of the operational amplifier power supply under test and the first terminal of the operational amplifier voltage measuring device 3, respectively. The control terminal is connected to the operational amplifier controller 1 and is used to select any operational amplifier switching module to connect its first terminal to its second terminal based on the control of the operational amplifier controller 1.

[0070] In this invention, considering that the DC adjustable voltage regulator module 2 needs to flexibly adjust its output voltage according to actual testing requirements, this solution sets up a switching module and several second DC power supplies with different output voltages. By controlling the switching module, the output voltage of any second DC power supply can be used as the output voltage of the DC adjustable voltage regulator module 2. Since the output voltages of each second DC power supply are different, the output voltage of the DC adjustable voltage regulator module 2 can be flexibly adjusted.

[0071] As an optional embodiment, the operational amplifier DC adjustable voltage regulator module 2 is a DC-DC (Direct Current to Direct Current Converter). The input terminal of the operational amplifier DC-DC converter is connected to a third DC power supply, and the output terminal is connected to the first terminal of the operational amplifier power supply under test and the first terminal of the operational amplifier voltage measuring device 3, respectively. The control terminal is connected to the operational amplifier controller 1 and is used to adjust the duty cycle of the internal switching transistor of the operational amplifier DC-DC converter based on the control of the operational amplifier controller 1 so that the operational amplifier DC-DC converter outputs the corresponding test voltage value.

[0072] In this invention, considering that the DC adjustable voltage regulator module 2 needs to flexibly adjust its output voltage according to actual testing requirements, this solution is equipped with a DC-DC converter. By simply changing the duty cycle of the switching transistor inside the DC-DC converter, the output voltage of the DC-DC converter can be flexibly adjusted, thereby realizing the flexible adjustment of the output voltage of the DC adjustable voltage regulator module 2.

[0073] As an optional embodiment, it also includes:

[0074] The protection device is connected at its first end to the operational amplifier DC adjustable voltage regulator module 2, and at its second end to the first end of the operational amplifier power supply under test and the first end of the operational amplifier voltage measuring device 3, respectively. It is used to disconnect when an overvoltage and / or overcurrent occurs in the circuit where the operational amplifier DC adjustable voltage regulator module 2 is located.

[0075] In this invention, considering that overvoltage and / or overcurrent conditions may occur in the circuit where the power supply under test is located, which may cause the power supply under test and other electronic components in the circuit to burn out, a protection device is added to the circuit to disconnect in time when overvoltage and / or overcurrent conditions occur in the circuit where the operational amplifier DC adjustable voltage regulator module 2 is located, thereby improving the safety of the solution.

[0076] It should be noted that in practical applications, the protective device can be a circuit breaker or a fuse, etc., which provides overvoltage protection and / or overcurrent protection.

[0077] This utility model also provides an embodiment of a voltage measurement system, including: a power supply under test and a voltage measuring device for an operational amplifier as described above, wherein the operational amplifier voltage measuring device is connected to the operational amplifier power supply under test.

[0078] The voltage measurement system provided in this embodiment corresponds to the voltage measurement device described above, and therefore has the same beneficial effects as the voltage measurement device described above. Therefore, for the embodiment of the voltage measurement system, please refer to the description of the embodiment of the voltage measurement device, which will not be repeated here.

[0079] It should be noted that, in this specification, relational terms such as "first" and "second" are used only to distinguish one entity or operation from another, and do not necessarily require or imply any such actual relationship or order between these entities or operations. Furthermore, the terms "comprising," "including," or any other variations thereof are intended to cover non-exclusive inclusion, such that a process, method, article, or apparatus that comprises a list of elements includes not only those elements but also other elements not expressly listed, or elements inherent to such a process, method, article, or apparatus. Without further limitations, an element defined by the phrase "comprising one..." does not exclude the presence of other identical elements in the process, method, article, or apparatus that includes said element.

[0080] The above description of the disclosed embodiments enables those skilled in the art to make or use the present invention. Various modifications to these embodiments will be readily apparent to those skilled in the art, and the general principles defined herein may be implemented in other embodiments without departing from the spirit or scope of the present invention. Therefore, the present invention is not to be limited to the embodiments shown herein, but is to be accorded the widest scope consistent with the principles and novel features disclosed herein.

Claims

1. A voltage measuring device, characterized in that, include: Controller, DC adjustable voltage regulator module, voltage measurement device; The controller is connected to the control terminal of the DC adjustable voltage regulator module, and the receiving terminal is connected to the output terminal of the voltage measuring device, for outputting a standard voltage to the DC adjustable voltage regulator module; The output terminal of the DC adjustable voltage regulator module is connected to the first terminal of the power supply under test, and is used to output the stable voltage converted from the standard voltage. The second terminal of the power supply under test is grounded; The first end of the voltage measuring device is connected to the DC adjustable voltage regulator module, and the second end is connected to the ground wire. It is used to transmit the first voltage value when the power supply under test is not turned on and the second voltage value after the power supply under test is turned on to the controller.

2. The voltage measuring device as described in claim 1, characterized in that, The DC adjustable voltage regulator module includes: a Zener diode, a first operational amplifier, a first resistor, a second resistor, a third resistor, and a first power electronic device; The first end of the first resistor is connected to the first DC power supply and the first end of the first power electronic device, respectively. The non-inverting input terminal of the first operational amplifier is connected to the second terminal of the first resistor and the cathode of the Zener diode, the negative-inverting input terminal is connected to the first terminal of the first resistor and the first terminal of the second resistor, and the output terminal is connected to the control terminal of the first power electronic device. The second terminal of the first power electronic device is connected to the second terminal of the first resistor, the first terminal of the power supply under test, and the first terminal of the voltage measuring device, respectively. The first power electronic device operates in the linear amplification region. The anode of the voltage regulator is connected to ground; The second terminal of the second resistor is grounded.

3. The voltage measuring device as described in claim 1, characterized in that, The DC adjustable voltage regulator module includes: a DAC chip, a second operational amplifier, a fourth resistor, a fifth resistor, and a second power electronic device; The control terminal of the DAC chip is connected to the controller and is used to output a corresponding DC voltage value based on the control of the controller. The non-inverting input terminal of the second operational amplifier is connected to the DAC chip, the negative-inverting input terminal is connected to the first terminal of the fourth resistor and the first terminal of the fifth resistor respectively, and the output terminal is connected to the control terminal of the second power electronic device. The first end of the second power electronic device is connected to the first DC power supply, and the second end is connected to the second end of the fourth resistor, the first end of the power supply under test, and the first end of the voltage measuring device. The second power electronic device operates in the linear amplification region. The second terminal of the fifth resistor is grounded.

4. The voltage measuring device as described in claim 3, characterized in that, The DC adjustable voltage regulator module also includes: The filtering module has its first end connected to the second end of the second power electronic device, the second end of the fourth resistor, the first end of the power supply under test, and the first end of the voltage measuring device, respectively, and its second end connected to the negative input terminal of the second operational amplifier, the first end of the fourth resistor, and the first end of the fifth resistor, respectively.

5. The voltage measuring device as described in claim 3, characterized in that, The second power electronic device is an NPN transistor, the base of which is the control terminal of the second power electronic device, the collector of which is the first terminal of the second power electronic device, and the emitter of which is the second terminal of the second power electronic device.

6. The voltage measuring device as described in claim 3, characterized in that, The second power electronic device is an N-type MOS transistor, the gate of the N-type MOS transistor is the control terminal of the second power electronic device, the drain of the N-type MOS transistor is the first terminal of the second power electronic device, and the source of the N-type MOS transistor is the second terminal of the second power electronic device.

7. The voltage measuring device as described in claim 1, characterized in that, The adjustable DC voltage regulator module includes: a switching module and several second DC power supplies with different output voltages; The switching module has several first terminals connected to each of the second DC power supplies with different output voltages, and its second terminals connected to the first terminals of the power supply under test and the voltage measuring device, respectively. The control terminal is connected to the controller and is used to select any one of the first terminals of the switching module to be connected to the second terminal of the switching module based on the control of the controller.

8. The voltage measuring device as described in claim 1, characterized in that, The adjustable DC voltage regulator module is a DC-DC converter. The input terminal of the DC-DC converter is connected to a third DC power supply, and the output terminal is connected to the first terminal of the power supply under test and the first terminal of the voltage measuring device, respectively. The control terminal is connected to the controller and is used to adjust the duty cycle of the internal switching transistor of the DC-DC converter based on the control of the controller so that the DC-DC converter outputs the corresponding test voltage value.

9. The voltage measuring device according to any one of claims 1 to 8, characterized in that, Also includes: A protection device, wherein the first end of the protection device is connected to the DC adjustable voltage regulator module, and the second end is connected to the first end of the power supply under test and the first end of the voltage measuring device, respectively, for disconnecting when an overvoltage and / or overcurrent occurs in the circuit where the DC adjustable voltage regulator module is located.

10. A voltage measurement system, characterized in that, include: The power supply under test and the voltage measuring device as described in any one of claims 1 to 9, wherein the voltage measuring device is connected to the power supply under test.

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