Voltage sampling circuit of novel battery assembly test system

Abstract

The utility model relates to the technical field of battery testing, in particular to a novel voltage sampling circuit of a battery assembly testing system. The system comprises a sampling unit; the circuit is characterized in that the circuit further comprises a voltage dividing unit, the input end of the voltage dividing unit is used for being connected with the detected high voltage, the output end of the voltage dividing unit is connected with the sampling unit through a low-voltage cable, the voltage dividing unit is used for converting the detected high voltage into a low-voltage signal and transmitting the low-voltage signal to the sampling unit through the low-voltage cable, and the cost of the circuit is low.

Description

Technical Field

[0001] This utility model relates to the field of battery testing technology, specifically a voltage sampling circuit for a novel battery assembly testing system. Background Technology

[0002] Traditional high-voltage battery assembly testing systems or energy storage systems typically use isolated sampling circuits for voltage sampling. After the high voltage to be measured is connected to the voltage sampling port of the testing system, a high-voltage harness is used to connect it to the sampling circuit on the circuit board. This high-voltage harness may be quite long, especially when the system has a large number of sampling channels.

[0003] Traditional designs have two drawbacks: First, the higher the voltage, the more expensive the high-voltage sampling cables become. This problem becomes more pronounced when the number of high-voltage sampling channels within the testing system increases, the system size expands, and the cables lengthen. Second, the insulation strength of the rubber insulation layer in high-voltage cables deteriorates over time due to cycling through high and low temperatures and humidity, leading to various problems. These problems include, but are not limited to: 1. Reduced measurement accuracy due to slight leakage current when high voltage is applied; 2. Equipment malfunction due to leakage current when high voltage is applied; 3. Equipment and personal safety issues caused by leakage current when high voltage is applied, etc.

[0004] To address the above issues, the existing technology proposes an improved solution by setting up a complete isolation sampling circuit at the high-voltage input port and then transmitting the weak-current isolated output signal of the sampling circuit, thereby minimizing or reducing the use of high-voltage sampling cables. However, this design is costly because each sampling section uses a complete isolation sampling circuit and a complete isolation power supply. Utility Model Content

[0005] The technical problem to be solved by this utility model is to provide a voltage sampling circuit for a novel battery assembly testing system, which has a low cost.

[0006] To solve the above problems, the following technical solutions are provided:

[0007] The voltage sampling circuit of the novel battery assembly testing system of this utility model includes a sampling unit; its feature is that it also includes a voltage divider unit. The input terminal of the voltage divider unit is used to connect to the high voltage to be measured, and the output terminal of the voltage divider unit is connected to the sampling unit through a low voltage cable. The voltage divider unit is used to convert the high voltage to be measured into a low voltage signal and transmit it to the sampling unit through the low voltage cable.

[0008] The input terminals of the voltage divider unit include a positive terminal and a negative terminal for high voltage input. The positive terminal is connected to the positive terminal of the high voltage being measured, and the negative terminal is connected to the negative terminal of the high voltage being measured. The output terminals of the voltage divider unit include a positive terminal and a negative terminal for low voltage input. Both the positive and negative terminals are connected to the sampling unit via low-voltage cables. The positive terminal for high voltage input is connected to the positive terminal for low voltage input through a voltage divider resistor one, and the negative terminal for high voltage input is connected to the negative terminal for low voltage input through a voltage divider resistor two. A voltage divider resistor three is connected in parallel between the positive and negative terminals for low voltage input.

[0009] The voltage divider resistor consists of resistors R1, R2, and R3 connected in series. The positive terminal of the high voltage input terminal is connected to the front end of resistor R1, and the rear end of resistor R3 is connected to the positive terminal of the low voltage terminal.

[0010] The voltage divider resistor consists of resistors R4, R5, and R6 connected in series. The negative terminal of the high-voltage input terminal is connected to the front end of resistor R4, and the rear end of resistor R6 is connected to the negative terminal of the low-voltage terminal.

[0011] The second voltage divider resistor includes a resistor R7, one end of which is connected to the positive terminal of the low-voltage terminal, and the other end of which is connected to the negative terminal of the low-voltage terminal.

[0012] The sampling unit includes an operational amplifier signal conditioning circuit, an ADC, and a microcontroller. The operational amplifier signal conditioning circuit is adapted to be connected to the low-voltage cable and the ADC, and the ADC is adapted to be connected to the microcontroller. The operational amplifier signal conditioning circuit is used to receive the low-voltage signal, condition the low-voltage signal, and send it to the ADC. The ADC converts the conditioned low-voltage signal into a digital signal and sends it to the microcontroller.

[0013] The operational amplifier signal conditioning circuit includes an operational amplifier U1B. The non-inverting input of operational amplifier U1B is connected to one end of resistor R2, one end of capacitor C2, and one end of resistor R3. The other end of resistor R2 is used for the low-voltage cable adapter connection, and the other ends of resistor R3 and capacitor C2 are grounded. The output of operational amplifier U1B is connected to the inverting input of operational amplifier U1B and one end of resistor R1. The other end of resistor R1 is connected to one end of capacitor C1, and the other end of capacitor C1 is grounded. One end of resistor R1 connected to capacitor C1 is connected to the ADC adapter.

[0014] The above approach has the following advantages:

[0015] In this novel battery assembly testing system, the input terminal of the voltage divider unit in the voltage sampling circuit is connected to the high-voltage being measured, while the output terminal is connected to the sampling unit via a low-voltage cable. The voltage divider unit converts the high-voltage being measured into a low-voltage signal, which is then transmitted to the sampling unit via the low-voltage cable. This sampling circuit utilizes the voltage divider unit to convert the measured voltage signal into a low-voltage signal, which is then transmitted to the sampling unit via the low-voltage cable. This sampling circuit eliminates the need for an isolation sampling circuit; the voltage divider unit can be constructed using resistors. Compared to isolation sampling units and isolation power supplies, resistors are less expensive, thus significantly reducing the overall cost of the battery assembly testing system. Attached Figure Description

[0016] Figure 1 This is a schematic diagram of the voltage sampling circuit of the novel battery assembly testing system of this utility model;

[0017] Figure 2 This is a circuit diagram of the voltage divider unit in the voltage sampling circuit of the novel battery assembly testing system of this utility model;

[0018] Figure 3 This is a circuit diagram of the sampling unit in the voltage sampling circuit of the novel battery assembly testing system of this utility model. Detailed Implementation

[0019] The present invention will be further described in detail below with reference to the accompanying drawings.

[0020] like Figure 1 As shown, the voltage sampling circuit of the novel battery assembly testing system of this utility model includes a sampling unit and a voltage divider unit. The input terminal of the voltage divider unit is used to connect to the high voltage to be measured, and the output terminal of the voltage divider unit is connected to the sampling unit through a low voltage cable. The voltage divider unit is used to convert the high voltage to be measured into a low voltage signal and transmit it to the sampling unit through the low voltage cable.

[0021] like Figure 2 As shown, the input terminals of the voltage divider unit include a positive terminal and a negative terminal for high voltage input. The positive terminal is connected to the positive terminal of the high voltage being measured, and the negative terminal is connected to the negative terminal of the high voltage being measured. The output terminals of the voltage divider unit include a positive terminal and a negative terminal for low voltage input. Both the positive and negative terminals are connected to the sampling unit via low-voltage cables.

[0022] The positive terminal of the high-voltage input terminal is connected to the positive terminal of the low-voltage terminal through a voltage divider resistor one, and the negative terminal of the high-voltage input terminal is connected to the negative terminal of the low-voltage terminal through a voltage divider resistor two. A voltage divider resistor three is connected in parallel between the positive and negative terminals of the low-voltage terminal. Voltage divider resistor one contains resistors R1, R2, and R3 connected in series. The positive terminal of the high-voltage input terminal is connected to the front end of resistor R1, and the rear end of resistor R3 is connected to the positive terminal of the low-voltage terminal. Voltage divider resistor two contains resistors R4, R5, and R6 connected in series. The negative terminal of the high-voltage input terminal is connected to the front end of resistor R4, and the rear end of resistor R6 is connected to the negative terminal of the low-voltage terminal. Voltage divider resistor two also contains resistor R7, one end of which is connected to the positive terminal of the low-voltage terminal, and the other end of which is connected to the negative terminal of the low-voltage terminal.

[0023] In this embodiment, as Figure 1 As shown, the battery assembly testing system contains n voltage divider units and n high-voltage input ports. The n voltage divider units are designated as voltage divider units 1 to n, and the n high-voltage input ports are designated as high-voltage input ports 1 to n. The voltage divider units are arranged in a one-to-one correspondence with the high-voltage input ports 1 to n. The positive and negative terminals of the high-voltage input terminals of the voltage divider units are connected to the positive and negative terminals of the corresponding high-voltage input ports, respectively. The low-voltage voltage after voltage division by the voltage divider circuit board is connected to the sampling unit through low-voltage cables 1 to n. The sampling unit is an independent circuit board used for voltage sampling.

[0024] like Figure 3As shown, in this embodiment, the operational amplifier signal conditioning circuit is connected to the low-voltage cable and the ADC adapter. The ADC is connected to the microcontroller adapter. The operational amplifier signal conditioning circuit receives the low-voltage signal, conditions it, and sends it to the ADC. The ADC converts the conditioned low-voltage signal into a digital signal and sends it to the microcontroller. Specifically, the sampling unit includes the operational amplifier signal conditioning circuit, the ADC, and the microcontroller. The operational amplifier signal conditioning circuit contains an operational amplifier U1B. The non-inverting input of operational amplifier U1B is connected to one end of resistor R2, one end of capacitor C2, and one end of resistor R3. The other end of resistor R2 is used to connect to the low-voltage cable adapter. In this embodiment, the other end of resistor R2 is connected to the positive terminal of the low-voltage terminal, and the negative terminal of the low-voltage terminal is grounded. The other end of resistor R3 and the other end of capacitor C2 are grounded. The output of operational amplifier U1B is connected to the inverting input of operational amplifier U1B and one end of resistor R1. The other end of resistor R1 is connected to one end of capacitor C1, and the other end of capacitor C1 is grounded. One end of resistor R1, which is connected to capacitor C1, is connected to the ADC adapter. In this embodiment, the ADC is an analog-to-digital converter (ADC). Resistor R1 is connected to pin 1 of the ADC. Pins 3 and 4 of the ADC are both connected to the microcontroller. Those skilled in the art can select the specific model of the ADC and the microcontroller as needed; this is prior art and will not be elaborated upon here.

[0025] In this embodiment, the high-voltage input port can be composed of a copper busbar, high-voltage terminals, etc., and is used to connect to an external high-voltage circuit. The voltage divider circuit consists of voltage divider resistors and a circuit board, and is used to divide the high voltage into a low voltage. The low-voltage cable can be composed of ordinary twisted-pair cable, and is used to transmit low-voltage signals. The sampling unit is used for voltage sampling.

[0026] The advantages of this solution are as follows:

[0027] 1. Low cost. This technical solution avoids or significantly reduces the use of high-voltage sampling cables. Because low-voltage ordinary cables are cheaper than high-voltage cables, the cost of the testing system can be reduced. The effect is particularly significant when the high-voltage cables are longer and more numerous.

[0028] In addition, compared with the scheme that places a complete isolated sampling circuit at the high voltage input port, this scheme does not add additional amplifiers, expensive isolators and isolated power supplies, etc., and has a low cost.

[0029] 2. High safety. Because high voltage is immediately reduced to low voltage upon entering the equipment, the number of high-voltage cables and terminals inside the equipment is reduced, avoiding many safety problems caused by high voltage. Since low-voltage cables transmit lower voltages, the possibility of leakage due to cable aging is significantly reduced. This improves the safety of both equipment and personnel.

[0030] 3. Reduced equipment performance deviation and improved equipment reliability. Because low-voltage cables transmit at low voltages, the possibility of leakage due to cable aging is greatly reduced, thus avoiding problems such as sampling accuracy deviation and equipment malfunction caused by leakage.

[0031] In operation, the high-voltage input enters the device through the high-voltage input port. A voltage divider circuit board located next to or directly connected to the high-voltage input port directly divides the high-voltage into a low-voltage signal. This results in all signals within the device being low-voltage signals. A low-voltage cable is then used to transmit the low-voltage signal to the sampling unit, completing the high-voltage sampling process. Specifically, when a 1200V voltage is input to the high-voltage input terminal, if the resistance of voltage divider resistors 1-6 is 1MΩ and the resistance of voltage divider resistor 7 is 62kΩ, the voltage at the low-voltage output terminal will be 12.27V, thus achieving the reduction of the high voltage to a low voltage.

Claims

1. A voltage sampling circuit of a novel battery assembly test system, comprising a sampling unit; characterized in that, It also includes a voltage divider unit. The input terminal of the voltage divider unit is connected to the high voltage being measured, and the output terminal of the voltage divider unit is connected to the sampling unit through a low voltage cable. The voltage divider unit is used to convert the high voltage being measured into a low voltage signal and transmit it to the sampling unit through the low voltage cable.

2. The voltage sampling circuit of the novel battery assembly test system of claim 1, wherein, The input terminals of the voltage divider unit include a positive terminal and a negative terminal for high voltage input. The positive terminal is connected to the positive terminal of the high voltage being measured, and the negative terminal is connected to the negative terminal of the high voltage being measured. The output terminals of the voltage divider unit include a positive terminal and a negative terminal for low voltage input. Both the positive and negative terminals are connected to the sampling unit via low-voltage cables. The positive terminal for high voltage input is connected to the positive terminal for low voltage input through a voltage divider resistor one, and the negative terminal for high voltage input is connected to the negative terminal for low voltage input through a voltage divider resistor two. A voltage divider resistor three is connected in parallel between the positive and negative terminals for low voltage input.

3. The voltage sampling circuit of the novel battery assembly test system of claim 2, wherein, The voltage divider resistor consists of resistors R1, R2, and R3 connected in series. The positive terminal of the high voltage input terminal is connected to the front end of resistor R1, and the rear end of resistor R3 is connected to the positive terminal of the low voltage terminal.

4. The voltage sampling circuit of the novel battery assembly test system of claim 2, wherein, The voltage divider resistor consists of resistors R4, R5, and R6 connected in series. The negative terminal of the high-voltage input terminal is connected to the front end of resistor R4, and the rear end of resistor R6 is connected to the negative terminal of the low-voltage terminal.

5. The voltage sampling circuit of the novel battery assembly test system of claim 2, wherein, The second voltage divider resistor includes a resistor R7, one end of which is connected to the positive terminal of the low-voltage terminal, and the other end of which is connected to the negative terminal of the low-voltage terminal.

6. The voltage sampling circuit of the novel battery assembly test system of claim 1, wherein, The sampling unit includes an operational amplifier signal conditioning circuit, an ADC, and a microcontroller. The operational amplifier signal conditioning circuit is adapted to be connected to the low-voltage cable and the ADC, and the ADC is adapted to be connected to the microcontroller. The operational amplifier signal conditioning circuit is used to receive the low-voltage signal, condition the low-voltage signal, and send it to the ADC. The ADC converts the conditioned low-voltage signal into a digital signal and sends it to the microcontroller.

7. The voltage sampling circuit of the novel battery assembly test system of claim 6, wherein, The operational amplifier signal conditioning circuit includes an operational amplifier U1B. The non-inverting input of operational amplifier U1B is connected to one end of resistor R2, one end of capacitor C2, and one end of resistor R3. The other end of resistor R2 is used for the low-voltage cable adapter connection, and the other ends of resistor R3 and capacitor C2 are grounded. The output of operational amplifier U1B is connected to the inverting input of operational amplifier U1B and one end of resistor R1. The other end of resistor R1 is connected to one end of capacitor C1, and the other end of capacitor C1 is grounded. One end of resistor R1 connected to capacitor C1 is connected to the ADC adapter.

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