Battery inspection unit

Abstract

The utility model discloses a battery inspection unit, which comprises an MCU (Microprogrammed Control Unit), a voltage detection module, a current detection module, a temperature detection module, a dial switch module and an RS485 communication module. The battery inspection unit provided by the utility model can improve the monitoring precision of battery voltage, battery current and battery temperature, and realizes stable charging and discharging of the battery. The voltage detection module filters and quantizes a sampling value for multiple times, the difference between the obtained sampling voltage value and an actual voltage value is very small, the measurement precision is high, and the battery voltage detection precision is greatly improved. According to the utility model, the current detection module filters and quantizes the sampling value for many times, the difference between the obtained sampling current value and the actual current value is small, the measurement precision is high, and the battery current detection precision is greatly improved. According to the temperature detection module, sampling values are filtered and quantified for multiple times, and final temperature conversion is carried out by adopting a table look-up method, so that the temperature detection precision of the battery is greatly improved.

Description

Technical Field

[0001] The utility model relates to the technical field of battery monitoring, in particular to a battery inspection unit. Background Art

[0002] With the development of industrial automation and Internet of Things technology, the demand for battery status monitoring is increasing, prompting the battery inspection unit to develop in the direction of intelligence and automation. Battery inspection includes communication detection and functional parameter detection of the battery. Communication detection uses RS485 to send and receive information for detection, while functional parameter detection uses voltage detection module, current detection module and temperature detection module for detection.

[0003] At present, most battery inspection units on the market have limited voltage, current and temperature detection accuracy, and cannot accurately monitor the actual status of the battery, resulting in misjudgment or missed detection. They cannot collect battery parameters in real time and transmit data remotely, and cannot perform predictive maintenance and fault alarms. Ordinary battery inspection units have low detection accuracy and cannot transmit battery parameters in real time, which cannot meet the inspection and maintenance work of batteries.

[0004] Therefore, the existing battery inspection unit needs to be improved. Utility Model Content

[0005] In view of the deficiencies in the prior art, the technical problem to be solved by the utility model is to provide a battery inspection unit. The purpose of designing the battery inspection unit is to realize the communication and functional parameter detection of the battery on the same circuit board, meet the accuracy requirements of various parameters of the battery inspection, remotely control the battery inspection, collect the battery status in real time, perform predictive maintenance and fault alarm, improve the battery detection efficiency and operation safety, save time and efficiency.

[0006] In order to solve the above technical problems, the utility model is implemented by the following scheme: A battery inspection unit of the utility model includes an MCU and also includes:

[0007] A voltage detection module electrically connected to the MCU and used to sample a battery voltage or a battery charging voltage;

[0008] A current detection module electrically connected to the MCU and used for detecting battery current;

[0009] A temperature detection module electrically connected to the MCU and used to detect the battery temperature;

[0010] A dip switch module electrically connected to the MCU.

[0011] Furthermore, the MCU is an 8-bit single-chip microcomputer based on the 8051 core, which has flash memory and RAM and supports ISP programming and IAP programming.

[0012] Furthermore, a plurality of high-speed optocoupler solid-state relays are arranged in the circuit of the voltage detection module for isolated data collection.

[0013] Furthermore, there are 27 high-speed optocoupler solid-state relays.

[0014] Furthermore, the current sampling circuit of the current detection module has multiple signal input ports to support the input of multiple signals.

[0015] Furthermore, the current detection module includes:

[0016] An operational amplifier U1A, wherein an inverting input terminal of the operational amplifier U1A is connected to an output terminal of the operational amplifier U1A;

[0017] A resistor R12, wherein a first end of the resistor R12 is connected to a non-inverting input terminal + of the operational amplifier U1A;

[0018] A capacitor C3, a first end of the capacitor C3 is connected to the second end of the resistor R12, and a second end of the capacitor C3 is grounded;

[0019] A resistor R15, wherein the resistor R15 is connected in parallel with the capacitor C3;

[0020] A resistor R13, wherein a first end of the resistor R13 is connected to an output end of the operational amplifier U1A;

[0021] An operational amplifier U1B, wherein the non-inverting input terminal of the operational amplifier U1B is connected to the second end of the resistor R13, and the inverting input terminal of the operational amplifier U1B is connected to the output terminal of the operational amplifier U1B;

[0022] A resistor R16, wherein a first end of the resistor R16 is connected to the non-inverting input end of the operational amplifier U1B, and a second end of the resistor R16 is connected to the temperature detection module;

[0023] A capacitor C5, a first end of the capacitor C5 is connected to the non-inverting input terminal of the operational amplifier U1B, and a second end of the capacitor C5 is grounded;

[0024] A resistor R14, wherein a first end of the resistor R14 is connected to the output end of the operational amplifier U1B, and a second end of the resistor R14 is connected to the P1.4 pin of the MCU;

[0025] A capacitor C4, wherein a first end of the capacitor C4 is connected to the M_BTI pin of the MCU, and a second end of the capacitor C4 is grounded.

[0026] Furthermore, the temperature detection module includes a resistor R17, a resistor R18, a resistor R19, a resistor R20, a resistor R21, a capacitor C6 and a capacitor C7;

[0027] The two ends of the resistors R17, R18, R19 and R21 connected in series are respectively connected to the P1.5 pin and the P1.6 pin of the MCU, wherein the circuit node between the resistors R18 and R19 is connected to the second end of the resistor R16, the circuit node between the resistors R17 and R18 is respectively connected to the first end of the capacitor C6 and the temperature acquisition sensor, the second end of the capacitor C6 is respectively connected to the first end of the resistor R20, the second end of the resistor R20 is connected to the circuit node between the resistors R19 and R21, and the capacitor C7 and the resistor R20 are connected in parallel.

[0028] Furthermore, the MCU is also connected to an RS485 communication module.

[0029] Compared with the prior art, the beneficial effects of the utility model are:

[0030] 1. The battery inspection unit of the utility model can improve the monitoring accuracy of battery voltage, battery current and battery temperature, and realize stable charging and discharging of the battery.

[0031] 2. The voltage detection module of the utility model filters and quantizes the sampled values ​​multiple times, so that the difference between the sampled voltage value and the actual voltage value is very small, the measurement accuracy is high, and the battery voltage detection accuracy is greatly improved.

[0032] 3. The current detection module of the utility model filters and quantizes the sampled values ​​multiple times, so that the difference between the sampled current value and the actual current value is small, the measurement accuracy is high, and the battery current detection accuracy is greatly improved.

[0033] 4. The temperature detection module of the utility model greatly improves the battery temperature detection accuracy by filtering and quantizing the sampled values ​​multiple times and using a table lookup method for the final temperature conversion. BRIEF DESCRIPTION OF THE DRAWINGS

[0034] Figure 1 This is a principle block diagram of the battery inspection unit of the utility model.

[0035] Figure 2 This is a circuit diagram of the voltage detection module of the utility model.

[0036] Figure 3 This is a circuit diagram of the current detection module of the utility model.

[0037] Figure 4 This is a circuit diagram of the temperature detection module of the utility model.

[0038] Figure 5 This is the MCU circuit diagram of the utility model.

[0039] Figure 6 for Figure 5Enlarged view of part A.

[0040] Figure 7 for Figure 5 Enlarged view of part B.

[0041] Figure 8 for Figure 5 Enlarged view of part C.

[0042] Fig. 9 for Figure 5 Enlarged view of part D.

[0043] Fig.10 It is a partial circuit diagram of a collection circuit connected to a battery for collecting voltage.

[0044] Fig.11 yes Fig.10 Enlarged view of part F.

[0045] Fig.12 yes Fig.10 Enlarged view of the G section.

[0046] Markings in the accompanying drawings: voltage detection module 1, current detection module 2, temperature detection module 3. DETAILED DESCRIPTION

[0047] The following will be combined with the drawings in the embodiments of the utility model to clearly and completely describe the technical solutions in the embodiments of the utility model, so that the advantages and features of the utility model can be more easily understood by those skilled in the art, thereby making a clearer and more explicit definition of the protection scope of the utility model. Obviously, the embodiments described in the utility model are only part of the embodiments of the utility model, not all of the embodiments. Based on the embodiments in the utility model, all other embodiments obtained by ordinary technicians in this field without making creative work are within the scope of protection of the utility model.

[0048] In addition, the technical features involved in the different embodiments of the present invention described below can be combined with each other as long as they do not conflict with each other.

[0049] Embodiment 1: The specific structure of the utility model is as follows:

[0050] Please refer to the attached Figure 1-12The utility model discloses a battery inspection unit, including an MCU. The model of the MCU used in the utility model is STC8A8K32S4. The MCU is an 8-bit single-chip microcomputer based on the 8051 core, which has flash memory and RAM, and supports ISP programming and IAP programming. The STC8A8K32S4 chip is an 8-bit single-chip microcomputer based on the 8051 core. This single-chip microcomputer has 8KB of flash memory and 256 bytes of RAM, supports ISP programming and IAP programming, and is suitable for various mid- and low-end embedded control systems. It has built-in multiple peripheral interfaces, such as UART serial port, timer / counter, PWM output, etc., as well as rich I / O ports, making it an ideal choice for home appliances, industrial control, and intelligent instrumentation. STC8A8K32S4 is widely used for its high performance, low power consumption, and easy development.

[0051] The battery inspection unit of the utility model further comprises a voltage detection module 1, a current detection module 2, a temperature detection module 3, a dial switch module, and an RS485 communication module.

[0052] A preferred technical solution of this embodiment: a plurality of high-speed optocoupler solid-state relays are arranged in the circuit of the voltage detection module for isolated data collection.

[0053] A preferred technical solution of this embodiment: the high-speed optical coupling solid-state relay is provided with 27. Figure 2 As shown, Figure 2 The high-speed optocoupler solid-state relay in is a local circuit of the voltage detection module. There are 5 high-speed optocoupler solid-state relays in this local circuit, namely high-speed optocoupler solid-state relay IS01, high-speed optocoupler solid-state relay IS02, high-speed optocoupler solid-state relay IS03, high-speed optocoupler solid-state relay IS04, and high-speed optocoupler solid-state relay IS05. The model of each high-speed optocoupler solid-state relay is TLP172GM.

[0054] The positive electrodes of the light-emitting ends of the high-speed optocoupler solid-state relay IS01, the high-speed optocoupler solid-state relay IS03, and the high-speed optocoupler solid-state relay IS04 are all connected to a first resistor, and the first resistors are resistors R1, R5, and R9, respectively, and the other ends of the first resistors are connected to each other and connected to VCC. A bidirectional diode D1 is connected between the negative electrode of the light-emitting end of the high-speed optocoupler solid-state relay IS01 and the negative electrode of the light-emitting end of the high-speed optocoupler solid-state relay IS03, and a bidirectional diode D2 is connected between the negative electrode of the light-emitting end of the high-speed optocoupler solid-state relay IS03 and the negative electrode of the light-emitting end of the high-speed optocoupler solid-state relay IS04, and the circuit node between the negative electrode of the bidirectional diode D1 is connected to the pin P0.0 of the MCU, and the circuit between the negative electrode of the bidirectional diode D2 is connected to P2.7 of the MCU.

[0055] The two pins of the light receiving end of the high-speed optocoupler solid-state relay IS01 are respectively connected to the BAT0 pin and the ME+ circuit of the battery under test.

[0056] The two pins of the light receiving end of the high-speed optocoupler solid-state relay IS03 are respectively connected to the BAT1 pin and the ME-circuit of the battery under test.

[0057] The two pins of the light receiving end of the high-speed optocoupler solid-state relay IS04 are respectively connected to the BAT2 pin and the ME+ circuit of the battery under test.

[0058] The positive poles of the light-emitting ends of the high-speed optocoupler solid-state relay IS02 and the high-speed optocoupler solid-state relay IS05 are connected to VCC, and the negative poles of the light-emitting ends are connected to the second resistors, which are resistors R3 and R11 respectively. The other end of resistor R3 is connected to the pin P4.0 of the MCU, and the other end of resistor R11 is connected to the pin P4.4 of the MCU. The first end of the light-receiving end of the high-speed optocoupler solid-state relay IS02 is connected to resistors R2 and R4 respectively, the other end of resistor R2 is connected to the ME+ circuit, and the other end of resistor R4 is grounded and connected to capacitor C1. The second end of the light-receiving end of the high-speed optocoupler solid-state relay IS02 is connected to the other end of capacitor C1 and resistor R6, and the other end of resistor R6 is connected to the ME+ circuit.

[0059] like Figure 10-12 As shown, the above ME+ circuit and ME- circuit are respectively connected to the optocoupler light receiving end of the voltage collection circuit.

[0060] The voltage detection module is connected to the P1.6 pin of the MCU. It is a 12-bit high-precision ADC inside the microcontroller. When it samples the battery voltage or battery charging voltage: the battery voltage or battery charging voltage V out The voltage divider circuit is used to obtain V out1 , V out1 =A1V out (A1 is the amplification gain, which is usually less than 1), V out1 As the input signal of the MCU's P1.6 pin (ADC), the ADC is V out1 Perform multiple sampling, filtering, quantization and conversion to obtain the sampled value ADC DATA , and then get the ADC reference voltage V REF , V REF =ADC REF *ADC resolution / ADC DATA , ADC REF is the internal test voltage of ADC, which is 1.344V. resolution is the resolution of the 12-bit ADC, which is 4095. Finally, the actual voltage value V voltage :V voltage=V REF *ADC DATA / ADC resolution Through multiple filtering and quantization of the sampled values, the obtained sampled voltage value is very close to the actual voltage value, and the measurement accuracy is not less than 99.7%, which can greatly improve the battery voltage detection accuracy.

[0061] The high-voltage DC voltage acquisition of this utility model uses 27 high-speed optocoupler solid-state relays for isolated acquisition, with a speed of up to 500us, and can achieve 3.75KV electrical isolation at the same time, truly achieving complete isolation of weak and strong electricity. The MCUIO port controls S1 and S2 to turn on the two optocouplers ISO1 and ISO3, and collects the ME+ ME-. ISO2 and ISO5 return the collected voltage value to the MCU ADC for processing. This circuit can collect 24 lead-acid batteries or other types of batteries, single-cell voltage and total battery pack voltage.

[0062] like Figure 3 As shown, a preferred technical solution of this embodiment: the current sampling circuit of the current detection module 2 has multiple signal input ports to support the input of multiple signals.

[0063] A preferred technical solution of this embodiment: the current detection module 2 includes:

[0064] An operational amplifier U1A, wherein an inverting input terminal of the operational amplifier U1A is connected to an output terminal of the operational amplifier U1A;

[0065] A resistor R12, wherein a first end of the resistor R12 is connected to a non-inverting input terminal + of the operational amplifier U1A;

[0066] A capacitor C3, a first end of the capacitor C3 is connected to the second end of the resistor R12, and a second end of the capacitor C3 is grounded;

[0067] A resistor R15, wherein the resistor R15 is connected in parallel with the capacitor C3;

[0068] A resistor R13, wherein a first end of the resistor R13 is connected to an output end of the operational amplifier U1A;

[0069] An operational amplifier U1B, wherein the non-inverting input terminal of the operational amplifier U1B is connected to the second end of the resistor R13, and the inverting input terminal of the operational amplifier U1B is connected to the output terminal of the operational amplifier U1B;

[0070] A resistor R16, wherein a first end of the resistor R16 is connected to the non-inverting input end of the operational amplifier U1B, and a second end of the resistor R16 is connected to the temperature detection module 3;

[0071] A capacitor C5, a first end of the capacitor C5 is connected to the non-inverting input terminal of the operational amplifier U1B, and a second end of the capacitor C5 is grounded;

[0072] A resistor R14, wherein a first end of the resistor R14 is connected to the output end of the operational amplifier U1B, and a second end of the resistor R14 is connected to the P1.4 pin of the MCU;

[0073] A capacitor C4, wherein a first end of the capacitor C4 is connected to the M_BTI pin of the MCU, and a second end of the capacitor C4 is grounded.

[0074] The current detection module 2 is connected to the P1.4 pin of the MCU and is a 12-bit high-precision ADC inside the microcontroller. The current detection module includes a current sensor and an operational amplifier. When detecting the battery current, the current sensor generates a voltage signal V proportional to the current. ITEMP Then the amplifier amplifies the weak voltage signal output by the current sensor to a range suitable for ADC (P1.4) input for digital processing to obtain the voltage value V of the input ADC IN1 ,V IN1 =V ITEMP *A (A is the amplifier gain). ADC to V IN1 Perform multiple sampling, filtering, quantization and conversion to obtain the sampled value ADC I , through the sampled value ADC I Get ADC reference voltage V REF , and then get the actual voltage value V voltage :V voltage =V REF *ADC I / ADC resolution The final detection current I current , I current =V voltage / B, B is the ratio of voltage to current in the current sensor. Through multiple filtering and quantization of the sampled values, the difference between the sampled current value and the actual current value is very small, and the measurement accuracy is not less than 99.7%, which can greatly improve the battery current detection accuracy.

[0075] The battery current sampling circuit of the utility model can support the input of multiple signals, such as: current Hall sensor, shunt, sampling resistor, etc., and can collect the charging and discharging current of the battery, that is, positive current during charging and negative current during discharging. BTI is the input signal, and after being followed by a first-stage precision operational amplifier, VREF is the reference source and divided by resistor R16 and resistor R13, and then reaches the 5th pin of the second-stage operational amplifier, and then filtered by resistor R14 current limiting capacitor C4 to the ADC of the MCU.

[0076] like Figure 4As shown, a preferred technical solution of this embodiment: the temperature detection module 3 includes a resistor R17, a resistor R18, a resistor R19, a resistor R20, a resistor R21, a capacitor C6 and a capacitor C7;

[0077] The two ends of the resistors R17, R18, R19 and R21 connected in series are respectively connected to the P1.5 pin and the P1.6 pin of the MCU, wherein the circuit node between the resistors R18 and R19 is connected to the second end of the resistor R16, the circuit node between the resistors R17 and R18 is respectively connected to the first end of the capacitor C6 and the temperature acquisition sensor, the second end of the capacitor C6 is respectively connected to the first end of the resistor R20, the second end of the resistor R20 is connected to the circuit node between the resistors R19 and R21, and the capacitor C7 and the resistor R20 are connected in parallel.

[0078] The temperature detection module 3 is connected to the P1.5 pin of the MCU and is a 12-bit high-precision ADC in the single-chip microcomputer. Battery temperature detection is usually achieved using an NTC thermistor. The resistance of the thermistor decreases as the temperature increases. OUT1 Connect the ADC channel of the MCU's P1.5 pin to the battery to form a voltage divider circuit. OUT1 Perform multiple sampling, filtering, quantization and conversion to obtain the sampled value ADC TEMP , the sampled value ADC is converted into TEMP Compared with the NTC resistance table, when NTC A

[0079] like Figure 4 As shown, VREF provides a stable reference source for two-way temperature acquisition through resistor R18 and resistor R19, resistor R20 is a precision NTC to collect internal operating temperature, TEMP_BT is for external battery operating temperature acquisition, resistor R17, capacitor C6, resistor R21, capacitor C7 are current limiting resistors and filter capacitors to the ADC of the MCU.

[0080] In the RS485 communication module, MCU's TXD2 (P1.1), MCU's RXD2 (P1.0), MCU's TX (P1.1) and MCU's RX (P1.0) are connected to the VIA and VIB pins of the digital isolator, and then the VOA and VOB pins of the digital isolator are connected one-to-one to the RO and DO pins of the 485 chip. By digitally isolating the 485 transmission and reception, the interference in the signal transmission process can be effectively reduced, and the stability and reliability of the communication can be ensured.

[0081] In summary, the battery inspection unit of the utility model can improve the monitoring accuracy of battery voltage, battery current, and battery temperature, and realize stable charging and discharging of the battery. The voltage detection module of the utility model filters and quantizes the sampled values ​​multiple times, and the difference between the sampled voltage value and the actual voltage value is very small, the measurement accuracy is high, and the battery voltage detection accuracy is greatly improved. The current detection module of the utility model filters and quantizes the sampled values ​​multiple times, and the difference between the sampled current value and the actual current value is small, the measurement accuracy is high, and the battery current detection accuracy is greatly improved. The temperature detection module of the utility model filters and quantizes the sampled values ​​multiple times, and uses a table lookup method for the final temperature conversion, which greatly improves the battery temperature detection accuracy.

[0082] The above description is only a preferred embodiment of the present invention, and does not limit the patent scope of the present invention. Any equivalent structure or equivalent process transformation made using the contents of the present invention specification and drawings, or directly or indirectly used in other related technical fields, are also included in the patent protection scope of the present invention.

Claims

1. A battery inspection unit, including an MCU, characterized in that: Also includes: A voltage detection module (1) electrically connected to the MCU and used to sample a battery voltage or a battery charging voltage; A current detection module (2) electrically connected to the MCU and used for detecting battery current; A temperature detection module (3) electrically connected to the MCU and used to detect the temperature of the battery; A dip switch module electrically connected to the MCU; The current detection module (2) comprises: An operational amplifier U1A, wherein an inverting input terminal of the operational amplifier U1A is connected to an output terminal of the operational amplifier U1A; A resistor R12, wherein a first end of the resistor R12 is connected to a non-inverting input terminal + of the operational amplifier U1A; A capacitor C3, a first end of the capacitor C3 is connected to the second end of the resistor R12, and a second end of the capacitor C3 is grounded; A resistor R15, wherein the resistor R15 is connected in parallel with the capacitor C3; A resistor R13, wherein a first end of the resistor R13 is connected to an output end of the operational amplifier U1A; An operational amplifier U1B, wherein the non-inverting input terminal of the operational amplifier U1B is connected to the second end of the resistor R13, and the inverting input terminal of the operational amplifier U1B is connected to the output terminal of the operational amplifier U1B; A resistor R16, wherein a first end of the resistor R16 is connected to the non-inverting input end of the operational amplifier U1B, and a second end of the resistor R16 is connected to the temperature detection module (3); A capacitor C5, a first end of the capacitor C5 is connected to the non-inverting input terminal of the operational amplifier U1B, and a second end of the capacitor C5 is grounded; A resistor R14, wherein a first end of the resistor R14 is connected to the output end of the operational amplifier U1B, and a second end of the resistor R14 is connected to the P1.4 pin of the MCU; A capacitor C4, wherein a first end of the capacitor C4 is connected to the M_BTI pin of the MCU, and a second end of the capacitor C4 is grounded.

2. The battery inspection unit according to claim 1, characterized in that: The MCU is an 8-bit single-chip microcomputer based on the 8051 core, has flash memory and RAM, and supports ISP programming and IAP programming.

3. The battery inspection unit according to claim 1, characterized in that: A plurality of high-speed optocoupler solid-state relays are arranged in the circuit of the voltage detection module for isolated data collection.

4. The battery inspection unit according to claim 3, characterized in that: There are 27 high-speed optocoupler solid-state relays.

5. The battery inspection unit according to claim 1, characterized in that: The current sampling circuit of the current detection module (2) has multiple signal input ports to support the input of multiple signals.

6. The battery inspection unit according to claim 1, characterized in that: The temperature detection module (3) comprises a resistor R17, a resistor R18, a resistor R19, a resistor R20, a resistor R21, a capacitor C6 and a capacitor C7; The two ends of the resistors R17, R18, R19 and R21 connected in series are respectively connected to the P1.5 pin and the P1.6 pin of the MCU, wherein the circuit node between the resistors R18 and R19 is connected to the second end of the resistor R16, the circuit node between the resistors R17 and R18 is respectively connected to the first end of the capacitor C6 and the temperature acquisition sensor, the second end of the capacitor C6 is respectively connected to the first end of the resistor R20, the second end of the resistor R20 is connected to the circuit node between the resistors R19 and R21, and the capacitor C7 and the resistor R20 are connected in parallel.

7. The battery inspection unit according to claim 1, characterized in that: The MCU is also connected to an RS485 communication module.

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