A portable battery performance testing device

Abstract

The present invention discloses a portable battery performance test device, comprising: a control module for sending a test digital signal; a digital-to-analog conversion module for performing digital-to-analog conversion on the received test digital signal to obtain a test analog signal; an operational amplifier module for performing operational amplifier processing on the test analog signal to obtain an operational amplifier signal; an AC power supply output module for outputting a test AC signal according to the operational amplifier signal; a signal acquisition module for acquiring an output signal of the test AC signal after passing through a tested battery; an internal resistance measurement module for performing internal resistance measurement on the output signal to obtain an internal resistance analog signal; an analog-to-digital conversion module for performing analog-to-digital conversion on the internal resistance analog signal to obtain an internal resistance digital signal; the control module is also used to receive the internal resistance digital signal to obtain an internal resistance test result, wherein the tested battery is converted into a power supply by a power supply module. The present invention has the technical characteristics of being portable and having accurate measurement.

Description

Technical Field

[0001] The invention belongs to the technical field of battery performance measurement, and in particular relates to a portable battery performance testing device. Background Art

[0002] The battery is a power supply component required by many electrical devices. It is a device that directly converts chemical energy into electrical energy. It is a battery designed to be rechargeable and is recharged through a reversible chemical reaction. It is a secondary battery.

[0003] The distribution terminal tester is a terminal used for power supply reliability detection and operation management of the distribution network. However, the existing distribution terminal tester does not have a battery testing function, cannot evaluate the performance of the battery, and cannot perform normal measurement work without power supply. Summary of the invention

[0004] The technical purpose of the present invention is to provide a portable battery performance testing device, which has the technical characteristics of portability and accurate measurement.

[0005] To solve the above problems, the technical solution of the present invention is:

[0006] A portable battery performance testing device, comprising:

[0007] Control module, digital-to-analog conversion module, operational amplifier module, AC power output module, output feedback module, signal acquisition module, internal resistance measurement module, analog-to-digital conversion module, power supply module;

[0008] The power supply module is used to convert the tested battery into a power supply to power the entire battery performance test device;

[0009] The control module is used to send a test digital signal, and the digital-to-analog conversion module is used to perform digital-to-analog conversion on the received test digital signal to obtain a test analog signal;

[0010] The operational amplifier module is used to perform operational amplifier processing on the test analog signal to obtain an operational amplifier signal; the AC power output module is used to output a test AC signal according to the operational amplifier signal, wherein the output feedback module is used to receive the test AC signal to obtain an output feedback signal, and the AC power output module is also used to perform offset adjustment on the test AC signal according to the output feedback signal;

[0011] The signal acquisition module is used to acquire the first output signal output after the test AC signal passes through the tested battery; the internal resistance measurement module is used to measure the internal resistance of the first output signal to obtain an internal resistance analog signal;

[0012] The analog-to-digital conversion module is used to perform analog-to-digital conversion on the internal resistance analog signal to obtain an internal resistance digital signal; the control module is also used to receive the internal resistance digital signal and calculate the internal resistance test result.

[0013] Further preferably, it also includes a capacity testing module, the signal acquisition module is also used to collect the second output signal of the tested battery discharge output, the capacity testing module is used to perform a capacity test on the second output signal to obtain a capacity analog signal; the analog-to-digital conversion module is also used to perform analog-to-digital conversion on the capacity analog signal to obtain a capacity digital signal; the control module is also used to receive the capacity digital signal and calculate the capacity test result.

[0014] Further preferably, the capacity testing module is provided with a recovery unit, and the recovery unit is used to perform feedback recovery on the second output signal to control and adjust the discharge current size of the second output signal.

[0015] Further preferably, the power supply module is a power supply circuit based on the power chip TPS54160A.

[0016] Further preferably, the test analog signal is a 0-2V step wave with a frequency of 1000 Hz, and the test AC signal is a ±1A sine wave.

[0017] Compared with the prior art, the present invention has the following advantages and positive effects:

[0018] When the present invention is testing, the power supply module can directly convert the electric energy of the battery into the working power required by the test device, while not affecting the performance test of the battery, eliminating the need for an independent power supply, and being easy to use and carry. The test AC signal for testing the internal resistance can be fed back through the output feedback circuit, thereby improving the accuracy of the internal resistance measurement. At the same time, by introducing a recovery unit in the battery capacity test, the actual discharge current of the battery can be read to improve the discharge accuracy, thereby improving the accuracy of the capacity test. BRIEF DESCRIPTION OF THE DRAWINGS

[0019] Figure 1 A structural block diagram of a portable battery performance testing device of the present invention;

[0020] Figure 2 A circuit diagram of a power supply module of a portable battery performance testing device of the present invention;

[0021] Figure 3 A circuit diagram of an output feedback module and an AC power output module of a portable battery performance test device of the present invention;

[0022] Figure 4The present invention discloses a circuit diagram of a capacity test module of a portable battery performance test device. DETAILED DESCRIPTION

[0023] In order to more clearly illustrate the embodiments of the present invention or the technical solutions in the prior art, the specific implementation methods of the present invention will be described below with reference to the accompanying drawings. Obviously, the accompanying drawings described below are only some embodiments of the present invention. For ordinary technicians in this field, other drawings and other implementation methods can be obtained based on these drawings without creative work.

[0024] In order to simplify the drawings, only the parts related to the present invention are schematically shown in each figure, and they do not represent the actual structure of the product. In addition, in order to simplify the drawings and facilitate understanding, in some figures, only one of the parts with the same structure or function is schematically drawn or marked. In this article, "one" not only means "only one", but also means "more than one".

[0025] The portable battery performance testing device proposed by the present invention is further described in detail below in conjunction with the accompanying drawings and specific embodiments.

[0026] See also Figure 1 The present application provides a portable battery performance testing device, comprising:

[0027] Control module, digital-to-analog conversion module, operational amplifier module, AC power output module, output feedback module, signal acquisition module, internal resistance measurement module, analog-to-digital conversion module, power supply module;

[0028] The power supply module is used to convert the tested battery into a power supply to power the entire battery performance test device; the control module is used to send a test digital signal, and the digital-to-analog conversion module is used to perform digital-to-analog conversion on the received test digital signal to obtain a test analog signal; the operational amplifier module is used to perform operational amplifier processing on the test analog signal to obtain an operational amplifier signal; the AC power supply output module is used to output a test AC signal according to the operational amplifier signal, wherein the output feedback module is used to receive the test AC signal to obtain an output feedback signal, and the AC power supply output module is also used to perform offset adjustment on the test AC signal according to the output feedback signal; the signal acquisition module is used to acquire the first output signal output after the test AC signal passes through the tested battery; the internal resistance measurement module is used to measure the internal resistance of the first output signal to obtain an internal resistance analog signal; the analog-to-digital conversion module is used to perform analog-to-digital conversion on the internal resistance analog signal to obtain an internal resistance digital signal; the control module is also used to receive the internal resistance digital signal and calculate the internal resistance test result.

[0029] The circuit of this implementation is now described in detail:

[0030] This embodiment designs a portable battery performance test device, which is powered by the tested battery during the test. The portable battery performance test device is composed of an MCU, a DA, an operational amplifier, an internal resistance test circuit (AC current output, signal measurement), and a capacity test circuit (DC discharge circuit, voltage measurement).

[0031] See also Figure 2 The power supply module of this embodiment directly uses the battery power supply circuit under test, wherein TPS54160A is used, and the low voltage shutdown pin is set to 11.7V, ensuring that the input voltage range is 12-60VDC and the output is 12VDC, so that batteries of all specifications can provide power for this system. Figure 2 , this embodiment also adjusts the voltage value through the power supply module to supply power to electronic components and circuits with different working voltages.

[0032] The internal resistance measurement module of this embodiment measures the voltage drop between the test AC signal before passing through the tested battery and the output feedback signal after passing through the tested battery, and obtains the internal resistance value according to the current value of the test AC signal.

[0033] See also Figure 3 DA1 is the test analog signal output by the digital-to-analog conversion module, AC7 is the output feedback signal, and IOUT is the test AC signal. The working principle of this part is that the control module of this embodiment outputs 1000HZ, 0-2V step wave (DA1) through the DA chip (i.e., the digital-to-analog conversion module), which is processed by various stages of operational amplifiers, wherein the first stage operational amplifier (U36B) is processed to become a ±1V step wave, and the second stage operational amplifier (U36A) is processed to become a sine wave, which is followed by the operational amplifier and enters the OPA548T, and finally outputs a ±1A sine wave to the battery, wherein R20 is a 50mΩ precision platinum resistor, VRR+ and VRR- are connected to the differential operational amplifier, and the output terminal AC7 is connected to the control module through the AD chip, that is, the voltage across the differential operational amplifier can be read, thereby calculating the actual current value of the test AC signal, so that the test digital signal can be adjusted to improve the accuracy of the test AC signal. Since there is an electrolytic capacitor (C24 in the figure) on the output side to isolate the DC voltage of the battery, and there is zero drift at the output end of the op amp, if the voltage at the output end of the op amp is not offset adjusted, the circuit will not operate normally after the capacitor is saturated. Therefore, the output voltage is fed back to achieve automatic offset adjustment. Figure 3 By introducing U7 as a feedback, the offset at the output of the op amp is offset.

[0034] Preferably, the present embodiment further includes: a capacity testing module, the signal acquisition module is further used to acquire a second output signal of the discharge output of the tested battery, the capacity testing module is used to perform a capacity test on the second output signal to obtain a capacity analog signal; the analog-to-digital conversion module is further used to perform an analog-to-digital conversion on the capacity analog signal to obtain a capacity digital signal; the control module is further used to receive the capacity digital signal and calculate the capacity test result.

[0035] Preferably, the capacity testing module is provided with a recovery unit, and the recovery unit is used to perform feedback recovery on the second output signal to control and adjust the discharge current size of the second output signal.

[0036] See also Figure 4 DA2 is the control signal output by the digital-to-analog conversion module for controlling the capacity test module, AC2 is the current sampling signal of the battery discharge, and IL is the discharge current of the battery discharge. Among them, AC2 is connected to the control module through the analog-to-digital conversion module, and IL is connected to the tested battery through the relay control switch. Figure 3 , the circuit is a MOS tube driving a large current amplifier circuit, equivalent to an electronic load. DA2 is the input signal, which is processed by the operational amplifier, and the MOS tube works in the amplification area. IL is connected to the battery under test to discharge it. The purpose of AC2 sampling is to read the actual discharge current value and improve the accuracy. The capacity test module of this embodiment uses a MOS tube to drive the current source and introduces sampling to ensure that the discharge current accuracy is high enough, making the power test more accurate.

[0037] When testing in this embodiment, the power supply module can directly convert the electric energy of the battery into the working power required by the test device, while not affecting the performance test of the battery, eliminating the need for an independent power supply, and being easy to use and carry. The output feedback circuit can provide feedback on the test AC signal for testing the internal resistance, thereby improving the accuracy of the internal resistance measurement. At the same time, by introducing a recovery unit in the battery capacity test, the actual discharge current of the battery can be read to improve the discharge accuracy, thereby improving the accuracy of the capacity test.

[0038] The embodiments of the present invention are described in detail above in conjunction with the accompanying drawings, but the present invention is not limited to the above embodiments. Even if various changes are made to the present invention, if these changes fall within the scope of the claims of the present invention and their equivalents, they still fall within the protection scope of the present invention.

Claims

1. A portable battery performance testing device, characterized in that: include: Control module, digital-to-analog conversion module, operational amplifier module, AC power output module, output feedback module, signal acquisition module, internal resistance measurement module, analog-to-digital conversion module, power supply module; The power supply module is used to convert the tested battery into a power supply to power the entire battery performance test device; The control module is used to send a test digital signal, and the digital-to-analog conversion module is used to perform digital-to-analog conversion on the received test digital signal to obtain a test analog signal; The operational amplifier module is used to perform operational amplifier processing on the test analog signal to obtain an operational amplifier signal; The AC power output module is used to output a test AC signal according to the operational amplifier signal, wherein the output feedback module is used to receive the test AC signal to obtain an output feedback signal, and the AC power output module is also used to perform an offset adjustment on the test AC signal according to the output feedback signal; The control module outputs 1000HZ, 0~2V step wave through the digital-to-analog conversion module, and finally outputs ±1A sine wave to the battery after being processed by various levels of operational amplifiers. The VRR+ and VRR- ends of the precision platinum resistor are connected to the differential operational amplifier. The output feedback signal AC7 at the output end is connected to the control module through the AD chip, which is used to read the voltage across the differential operational amplifier, so as to calculate the actual current value of the test AC signal IOUT, and adjust the test digital signal to improve the accuracy of the test AC signal; the output side isolates the DC voltage of the battery through an electrolytic capacitor, and the output end of the operational amplifier includes a zero drift. By introducing U7 as a feedback, the offset of the output end of the operational amplifier is offset, and the voltage at the output end of the operational amplifier is fed back to realize automatic offset adjustment; The signal acquisition module is used to acquire the first output signal output after the test AC signal passes through the tested battery; the internal resistance measurement module is used to measure the internal resistance of the first output signal to obtain an internal resistance analog signal; The analog-to-digital conversion module is used to perform analog-to-digital conversion on the internal resistance analog signal to obtain an internal resistance digital signal; the control module is also used to receive the internal resistance digital signal and calculate the internal resistance test result; It also includes a capacity test module, the signal acquisition module is further used to collect the second output signal of the tested battery discharge output, the capacity test module is used to perform a capacity test on the second output signal to obtain a capacity analog signal; the analog-to-digital conversion module is further used to perform an analog-to-digital conversion on the capacity analog signal to obtain a capacity digital signal; the control module is further used to receive the capacity digital signal and calculate the capacity test result; The capacity test module is provided with a recovery unit, and the recovery unit is used to perform feedback recovery on the second output signal to control and adjust the discharge current size of the second output signal; The current sampling signal AC2 of battery discharge is connected to the control module via the analog-to-digital conversion module, and the discharge current IL of the battery discharge is connected to the battery under test via the relay control switch. The control signal DA2 output by the digital-to-analog conversion module for controlling the capacity test module is used as an input signal. After being processed by the operational amplifier, the MOS tube works in the amplification area, and the discharge current IL of the battery discharge is connected to the battery under test to discharge it. The purpose of sampling the current sampling signal AC2 of the battery discharge is to read the actual discharge current value and improve the accuracy.

2. The portable battery performance testing device according to claim 1, characterized in that: The power supply module is a power supply circuit based on the power chip TPS54160A.

3. The portable battery performance testing device according to claim 1, characterized in that: The test simulation signal is a 0-2V step wave with a frequency of 1000 Hz, and the test AC signal is a ±1A sine wave.

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