CN-224216772-U - Voltage measuring device and system

CN224216772UCN 224216772 UCN224216772 UCN 224216772UCN-224216772-U

Abstract

The utility model discloses a voltage measuring device and a system, which relate to the field of testing, and consider that voltage drop possibly exists at two ends of the existing lithium battery testing power supply so as to influence the accuracy of the charge and discharge testing of the lithium battery, therefore, the scheme is provided with a controller, a direct current adjustable voltage stabilizing module and a voltage measuring device in the voltage measuring device, and the controller is used for controlling the power supply to be tested to be put into a loop where the direct current adjustable voltage stabilizing module is positioned so as to automatically measure the voltage drop of the power supply to be tested, the voltage drop of the test power supply is not required to be measured repeatedly by using manpower and material resources, and the voltage value output by the direct-current adjustable voltage stabilizing module is always kept stable, so that the first voltage value when the power supply to be tested is not put into and the second voltage value after the power supply to be tested is put into can be accurately measured, the controller can calibrate the power supply to be tested according to the first voltage value and the second voltage value, the voltage drop at two ends of the power supply to be tested is eliminated, and the accuracy of the charge and discharge test of the lithium battery is further ensured.

Inventors

CHEN HAO
ZHANG KAIHUA
LUO JIAYU
LIU CHAO

Assignees

华自科技股份有限公司

Dates

Publication Date: 20260508
Application Date: 20250523

Claims (10)

1. The voltage measuring device is characterized by comprising a controller, a direct-current adjustable voltage stabilizing module and a voltage measuring device; The controller is connected with the control end of the direct current adjustable voltage-stabilizing module, and the receiving end is connected with the output end of the voltage measuring device and used for outputting standard voltage to the direct current adjustable voltage-stabilizing module; the output end of the direct current adjustable voltage stabilizing module is connected with the first end of the power supply to be tested and is used for outputting the stabilized voltage converted from the standard voltage; the second end of the power supply to be tested is grounded; the first end of the voltage measuring device is connected with the direct current adjustable voltage stabilizing module, the second end of the voltage measuring device is connected with the ground wire, and the voltage measuring device is used for transmitting the measured first voltage value when the power to be measured is not input and the measured second voltage value after the power to be measured is input to the controller.
2. The voltage measurement device of claim 1, wherein the DC adjustable voltage regulator module comprises a voltage regulator tube, 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 with a first direct current power supply and the first end of the first power electronic device respectively; The positive phase input end of the first operational amplifier is respectively connected with the second end of the first resistor and the cathode of the voltage stabilizing tube, the negative phase input end of the first operational amplifier is respectively connected with the first end of the first resistor and the first end of the second resistor, and the output end of the first operational amplifier is connected with the control end of the first power electronic device; The second end of the first power electronic device is respectively connected with the second end of the first resistor, the first end of the power supply to be tested and the first end of the voltage measuring device, and the first power electronic device works in a linear amplifying region; the anode of the voltage stabilizing tube is connected with the ground; the second end of the second resistor is grounded.
3. The voltage measurement device of claim 1, wherein the DC adjustable voltage regulator module comprises a DAC chip, a second operational amplifier, a fourth resistor, a fifth resistor, and a second power electronic device; The control end of the DAC chip is connected with the controller and is used for outputting a corresponding direct-current voltage value based on the control of the controller; The positive phase input end of the second operational amplifier is connected with the DAC chip, the negative phase input end of the second operational amplifier is respectively connected with the first end of the fourth resistor and the first end of the fifth resistor, and the output end of the second operational amplifier is connected with the control end of the second power electronic device; The first end of the second power electronic device is connected with a first direct current power supply, the second end of the second power electronic device is respectively connected with the second end of the fourth resistor, the first end of the power supply to be tested and the first end of the voltage measuring device, and the second power electronic device works in a linear amplifying region; The second end of the fifth resistor is grounded.
4. The voltage measurement device of claim 3 wherein the dc adjustable voltage regulation module further comprises: The first end of the filtering module is respectively connected with the second end of the second power electronic device, the second end of the fourth resistor, the first end of the power to be measured and the first end of the voltage measuring device, and the second end of the filtering module is respectively connected with the negative-phase input end of the second operational amplifier, the first end of the fourth resistor and the first end of the fifth resistor.
5. The voltage measurement device of claim 3 wherein the second power electronic device is an NPN transistor, a base of the NPN transistor is a control terminal of the second power electronic device, a collector of the NPN transistor is a first terminal of the second power electronic device, and an emitter of the NPN transistor is a second terminal of the second power electronic device.
6. The voltage measurement device of claim 3 wherein the second power electronic device is an N-type MOS transistor, a gate of the N-type MOS transistor is a control terminal of the second power electronic device, a drain of the N-type MOS transistor is a first terminal of the second power electronic device, and a source of the N-type MOS transistor is a second terminal of the second power electronic device.
7. The voltage measurement device of claim 1, wherein the DC adjustable voltage stabilizing module comprises a switching module and a plurality of second DC power sources with different output voltages; The first ends of the switching modules are connected with the second direct current power supplies with different output voltages in a one-to-one correspondence mode, the second ends of the switching modules are respectively connected with the first ends of the power supplies to be tested and the first ends of the voltage measuring devices, and the control ends of the switching modules are connected with the controller and are used for selecting any one of the first ends of the switching modules to be connected with the second ends of the switching modules based on the control of the controller.
8. The voltage measurement device of claim 1, wherein the dc adjustable voltage stabilizing module is a DCDC converter, an input end of the DCDC converter is connected to a third dc power supply, an output end of the DCDC converter is connected to a first end of the power supply to be measured and a first end of the voltage measurement device, respectively, and a control end of the DCDC converter is connected to the controller, and is used for adjusting a duty ratio of a switching tube in the DCDC converter based on control of the controller, so that the DCDC converter outputs a corresponding test voltage value.
9. The voltage measurement device of any one of claims 1 to 8, further comprising: The first end of the protection device is connected with the direct current adjustable voltage stabilizing module, and the second end of the protection device is respectively connected with the first end of the power supply to be tested and the first end of the voltage measuring device and is used for being disconnected when an overvoltage condition and/or an overcurrent condition occurs in a loop where the direct current adjustable voltage stabilizing module is located.
10. A voltage measurement system comprising a power supply to be measured and a voltage measurement device according to any one of claims 1 to 9, said voltage measurement device being connected to said power supply to be measured.

Description

Voltage measuring device and system Technical Field The present utility model relates to the field of testing, and in particular, to a voltage measurement device and system. Background When the lithium batteries are subjected to hot-pressing formation and capacity division, a test power supply is required to be connected between the positive electrode and the negative electrode of each lithium battery, namely, a large current is conducted between the positive electrode and the negative electrode of each lithium battery to carry out charge and discharge test, namely, the data such as the capacity and the internal resistance of the battery cells are analyzed through charge and discharge of the battery cells of the lithium batteries, the quality grades of the battery cells of the lithium batteries are determined, and the lithium batteries with the quality grades of the same battery cells are selected for series connection or parallel connection application. However, if there is a voltage drop in the test power supply of the lithium battery, an error is caused in the test result of the battery cell of the lithium battery, and the existing method for measuring the voltage drop of the test power supply needs to be measured by an operator by holding an external device. Disclosure of utility model The utility model aims to provide a voltage measuring device and a system, the voltage drop of a power to be measured is automatically measured by controlling a loop in which the power to be measured is put into a direct current adjustable voltage stabilizing module through a controller, the voltage drop of the power to be measured is not required to be repeatedly measured by manpower and material resources, and the voltage value output by the direct current adjustable voltage stabilizing module is always stable, so that a first voltage value when the power to be measured is not put into and a second voltage value after the power to be measured are accurately measured, the power to be measured is conveniently calibrated by the controller according to the first voltage value and the second voltage value, the voltage drop at two ends of the power to be measured is eliminated, and the accuracy of the charge and discharge test of a lithium battery is further ensured. In order to solve the technical problems, the utility model provides a voltage measuring device which comprises a controller, a direct-current adjustable voltage stabilizing module and a voltage measuring device; The controller is connected with the control end of the direct current adjustable voltage-stabilizing module, and the receiving end is connected with the output end of the voltage measuring device and used for outputting standard voltage to the direct current adjustable voltage-stabilizing module; the output end of the direct current adjustable voltage stabilizing module is connected with the first end of the power supply to be tested and is used for outputting the stabilized voltage converted from the standard voltage; the second end of the power supply to be tested is grounded; the first end of the voltage measuring device is connected with the direct current adjustable voltage stabilizing module, the second end of the voltage measuring device is connected with the ground wire, and the voltage measuring device is used for transmitting the measured first voltage value when the power to be measured is not input and the measured second voltage value after the power to be measured is input to the controller. Optionally, the direct current adjustable voltage stabilizing module comprises a voltage stabilizing tube, 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 with a first direct current power supply and the first end of the first power electronic device respectively; The positive phase input end of the first operational amplifier is respectively connected with the second end of the first resistor and the cathode of the voltage stabilizing tube, the negative phase input end of the first operational amplifier is respectively connected with the first end of the first resistor and the first end of the second resistor, and the output end of the first operational amplifier is connected with the control end of the first power electronic device; The second end of the first power electronic device is respectively connected with the second end of the first resistor, the first end of the power supply to be tested and the first end of the voltage measuring device, and the first power electronic device works in a linear amplifying region; the anode of the voltage stabilizing tube is connected with the ground; the second end of the second resistor is grounded. Optionally, the direct current adjustable voltage stabilizing module comprises a DAC chip, a second operational amplifier, a fourth resistor, a fifth resistor and a second power electronic de