Multiplexed controllable battery simulation device

Abstract

The embodiment of the application provides a kind of multi-path controllable battery simulation device, including DC power supply, microcontroller and at least one battery string simulation unit;Battery string simulation unit is used to simulate the output voltage of battery string, it includes digital-analog conversion module and multiple series-connected battery cell simulation modules;Microcontroller is used to generate multi-path controllable voltage digital signal, output to digital-analog conversion module;Digital-analog conversion module includes multiple analog voltage output channels, respectively with multiple battery cell simulation modules are connected;Battery cell simulation module is used to carry out signal isolation and voltage adjustment to the received analog voltage signal;Each battery cell simulation module includes isolated power supply, isolation operational amplifier, co-directional operational amplifier and voltage follower, digital-analog conversion module, isolation operational amplifier, co-directional operational amplifier and voltage follower are sequentially connected;DC power supply is connected with microcontroller and at least one battery string simulation unit respectively, and provides working voltage for it.Simplify the circuit structure, improve the precision and compatibility of simulation, reduce cost.

Description

Technical Field

[0001] This application relates to the field of energy storage technology, and in particular to a multi-channel controllable battery simulation device. Background Technology

[0002] In the research and development of energy storage products, it is often necessary to conduct charge and discharge tests on individual lithium battery cells and lithium battery modules, such as tests on the battery management system (BMS), cycle tests on lithium batteries, and tests on the energy management system (EMS). If real lithium batteries are used for testing, not only is the cost high, but the voltage, current, and temperature of physical batteries change slowly, making them inflexible in use, resulting in problems such as time-consuming testing and high development costs.

[0003] Current battery model devices can be broadly categorized into two implementation methods: analog circuits and digital circuits. Analog circuit implementations use resistors to regulate voltage. However, due to stress release issues within the adjustable resistors, the output voltage tends to drift after a period of time following the voltage setting, resulting in poor accuracy and often requiring secondary adjustments. When adjusting multiple voltage values, each resistor must be manually adjusted until a suitable output voltage is achieved, a cumbersome and time-consuming process with poor accuracy, making it difficult to accurately simulate the discharge curve of a lithium battery. Digital circuit implementations, on the other hand, suffer from complex circuit structures and high costs. For example, document CN206671507U discloses a battery simulator where each analog voltage control module includes a microcontroller (MCU), an A / D converter chip, and a D / A converter chip, leading to a complex circuit structure and high cost. Summary of the Invention

[0004] In view of this, the present application provides a multi-channel controllable battery simulation device to solve at least one problem existing in the background art.

[0005] An embodiment of this application provides a multi-channel controllable battery simulation device, including: a DC power supply, a microcontroller, and at least one battery string simulation unit; the battery string simulation unit is used to simulate the output voltage of a battery string, and includes a digital-to-analog conversion module and multiple cell simulation modules connected in series. The microcontroller is connected to the digital-to-analog converter module and is used to generate multiple controllable digital voltage signals and output them to the digital-to-analog converter module. The digital-to-analog converter module includes multiple analog voltage output channels, each of which is connected to multiple cell simulation modules to convert the received digital voltage signals into multiple analog voltage signals and output them to the multiple cell simulation modules. The cell simulation module is used to isolate and adjust the received analog voltage signal; each cell simulation module includes an isolated power supply, an isolated operational amplifier, a non-inverting operational amplifier, and a voltage follower, and the digital-to-analog converter module, the isolated operational amplifier, the non-inverting operational amplifier, and the voltage follower are connected in sequence; The DC power supply is connected to the microcontroller and the at least one battery string simulation unit, respectively, to provide them with operating voltage.

[0006] In an optional embodiment, the cell simulation module is further used to electrically isolate the DC power supply. The isolated power supply is connected to the DC power supply, the isolated operational amplifier, the non-inverting operational amplifier, and the voltage follower, respectively. The isolated operational amplifier is also connected to the DC power supply.

[0007] In one alternative embodiment, the microcontroller includes two or more battery string simulation units, and the microcontroller is connected to the different battery string simulation units in a multi-stage series manner.

[0008] In one optional embodiment, the isolated power supply includes an isolation chip, which includes a voltage input terminal, a voltage output terminal, a first ground terminal, and a second ground terminal. The voltage input terminal is used to receive a first operating voltage output by the DC power supply, and the voltage output terminal is used to output a second operating voltage. The first ground terminal and the second ground terminal do not share a common ground.

[0009] In one optional embodiment, the digital-to-analog conversion module includes a digital-to-analog conversion chip and a reference voltage source, wherein the reference voltage source is connected to the reference voltage terminal of the digital-to-analog conversion chip and is used to provide a reference voltage to the digital-to-analog conversion chip.

[0010] In one optional embodiment, the reference voltage source includes a voltage regulator chip. The power supply pin of the voltage regulator chip is connected to a DC power supply via a first adjustment resistor to receive a first operating voltage. The voltage output pin of the voltage regulator chip is connected to a first ground via a third adjustment resistor. The voltage output pin is connected to the reference voltage terminal of the digital-to-analog converter chip via a second adjustment resistor, a first adjustment resistor, and a current-limiting resistor in sequence. The power supply pin is connected between the current-limiting resistor and the second adjustment resistor. The ground pin of the voltage regulator chip is connected to the first ground.

[0011] In one optional embodiment, the isolation operational amplifier includes an isolation operational amplifier chip. The isolation operational amplifier chip includes a first operating voltage input terminal, a second operating voltage input terminal, a signal input terminal, a signal output terminal, a first ground terminal, and a second ground terminal. The first operating voltage input terminal is connected to the DC power supply output terminal to receive a first operating voltage. The second operating voltage input terminal is connected to the voltage output terminal of the isolation chip to receive a second operating voltage. The signal input terminal is connected to one of the outputs of the digital-to-analog converter chip. The signal output terminal is connected to the non-inverting input terminal of the non-inverting operational amplifier to output an isolated voltage signal. The first ground terminal and the second ground terminal are respectively connected to a first ground and a second ground.

[0012] In one optional embodiment, the non-inverting operational amplifier includes a power supply terminal, a ground terminal, a non-inverting input terminal, an inverting input terminal, and a signal output terminal. The power supply terminal is connected to the voltage output terminal of the isolation power supply to obtain the second operating voltage. The ground terminal of the non-inverting operational amplifier is connected to a second ground. The output terminal of the non-inverting operational amplifier is connected to the non-inverting input terminal of the voltage follower. The output terminal of the non-inverting operational amplifier is connected to the second ground via a seventh adjustment resistor and an eighth adjustment resistor. The inverting input terminal of the non-inverting operational amplifier is connected between the seventh adjustment resistor and the eighth adjustment resistor.

[0013] In one optional embodiment, the voltage follower includes a power supply terminal, a ground terminal, a non-inverting input terminal, an inverting input terminal, and an output terminal. The power supply terminal of the voltage follower is connected to the voltage output terminal of the isolated power supply to obtain the second operating voltage. The ground terminal of the voltage follower is connected to a second ground. The inverting input terminal of the voltage follower is directly connected to its output terminal. The output terminal of the voltage follower is connected to an output interface.

[0014] The multi-channel controllable battery simulation device provided in this application uses a microcontroller combined with a high-precision multi-channel digital-to-analog converter (DAC) module to simulate voltage output digitally. The microcontroller allows for batch setting of the output voltage of multiple cells and multiple battery strings, providing flexible and convenient adjustment, improving output voltage accuracy, and simulating battery discharge curves. Furthermore, only one microcontroller is needed to independently simulate the output voltage of multiple individual cells and multiple battery strings, simplifying the circuit structure and reducing costs. By using a high-precision multi-channel DAC module combined with an isolation operational amplifier to electrically isolate the multiple output voltages from the DAC module, independent output voltages for each cell simulation module are achieved, simultaneously simulating multiple individual cells. Each battery string simulation unit uses only one DAC module, further simplifying the circuit structure and reducing costs.

[0015] A voltage follower is used to improve load-carrying capacity, simulating the driving capability of a real battery cell. The output voltage of a battery string is simulated by connecting the output voltages of multiple cell simulation modules in series. A multi-stage series connection between the microprocessor and multiple battery string simulation units improves the scalability of the battery string simulation unit, simplifies wiring, and enhances compatibility with the battery management system.

[0016] Additional aspects and advantages of this application will be set forth in part in the description which follows, and in part will be obvious from the description, or may be learned by practice of this application. Attached Figure Description

[0017] Figure 1 This is a schematic diagram of the structure of a multi-channel controllable battery simulation device provided in an embodiment of this application; Figure 2 This is a circuit diagram of a digital-to-analog conversion module in one embodiment of this application; Figure 3 This is a circuit diagram of an isolated power supply in one embodiment of this application; Figure 4 This is a circuit diagram of an isolated power supply, a non-inverting operational amplifier, and a voltage follower in one embodiment of this application. Detailed Implementation

[0018] To make the technical solutions and beneficial effects of this application more apparent and understandable, the technical solutions in the embodiments of this application are clearly and completely described below by listing specific examples. Obviously, the described embodiments are only a part of the embodiments of this application, and not all of them. Based on the embodiments in this application, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of this application.

[0019] Unless otherwise defined, all technical and scientific terms used herein have the same meaning as commonly understood by one of ordinary skill in the art to which this application belongs. The terminology used in this specification is for the purpose of describing particular embodiments only and is not intended to be limiting of the application.

[0020] It should be noted that the terms "first," "second," etc., used in this application may be used to describe various elements, but these elements are not limited by these terms. These terms are used only to distinguish one element from another, and not to describe a specific order or sequence. The terms "comprising" and "having," and any variations thereof, are intended to cover non-exclusive inclusion, not excluding the presence or addition of one or more other features.

[0021] This application provides a multi-channel controllable battery simulation device for simulating the dynamic voltage output of individual battery cells, including lithium batteries, as well as battery strings and battery packs. A battery string is a power supply device formed by connecting multiple individual battery cells in series. A battery pack is a power supply device formed by connecting multiple battery strings in series or parallel. Please refer to... Figure 1 The system includes a microcontroller (MCU) 10, a DC power supply 70, and at least one battery string simulation unit. The DC power supply 70 is connected to both the MCU 10 and the at least one battery string simulation unit to provide them with operating voltage. Optionally, the output voltage of the DC power supply 70 is 5V to 12V. By using a low-voltage DC power supply, the circuit structure is simplified compared to AC mains power, and safety hazards are avoided.

[0022] The microcontroller (MCU) 10 is used to output voltage control commands to each digital-to-analog converter (DAC) module to control the output voltage of each DAC module, thereby controlling the output voltage of each cell simulation module and each battery string simulation module. The microcontroller 10 is connected to the DAC module and is used to generate multiple controllable digital voltage signals, which are then output to the DAC module. Optionally, the microcontroller can be a single-chip microcomputer or an ARM processor.

[0023] The microcontroller 10 controls the output voltage of each cell simulation module and each battery string simulation unit, thereby achieving controllable output voltage. The microcontroller 10 stores the voltage timing data of each cell's discharge curve and outputs corresponding digital signals through the I / O ports according to the timing requirements of the DAC chip. When simulating a battery discharge curve (waveform), the microcontroller 10 first reads the pre-stored timing relationship between time and voltage. When the running time is T0, it outputs the voltage corresponding to time T0; when the time reaches T1, it outputs the voltage value corresponding to time T1, and so on, until the current waveform is output. This process simulates the battery discharge curves of cells and battery strings in different states.

[0024] The digital-to-analog converter module includes multiple analog voltage output channels and is connected to multiple cell simulation modules. It converts the received digital voltage signals into multiple analog voltage signals and outputs them to multiple cell simulation modules within the same battery string simulation module. The cell simulation modules perform signal isolation and voltage adjustment on the received analog voltage signals, as well as electrical isolation of the DC power supply, thereby enabling the series output of multiple cell simulation modules.

[0025] The battery string simulation unit is used to simulate the output voltage of a single battery cell and the output voltage of the battery string. Figure 1The diagram illustrates m battery string simulation units, denoted as the first battery string simulation unit, the second battery string simulation unit, and so on, up to the mth battery string simulation unit. These battery string simulation units are connected in series or in parallel. Each battery string simulation unit has the same structure, including a digital-to-analog converter (DAC) module and multiple cell simulation modules. The first battery string simulation unit includes a DAC module 21, a first cell simulation module 111, a second cell simulation module 112, and so on, up to the nth cell simulation module 11n. The second battery string simulation unit includes a DAC module 22, and first cell simulation modules 121 through 12n. The mth battery string simulation unit includes the mth DAC module 2m, first cell simulation modules 1m1, and so on, up to the nth cell simulation module 1mn. Here, n is a natural number greater than or equal to 2, for example, n equals 8 or 16; m is a natural number greater than or equal to 1, meaning it includes one or more battery string simulation units.

[0026] This system employs a microcontroller combined with a multi-channel digital-to-analog converter (DAC) module to digitally simulate voltage output. It allows for batch setting of output voltages for multiple cells and battery strings, offering flexible and convenient adjustments, improved output voltage accuracy, and an adjustment step of up to 1mV. This enables the simulation of discharge curves for multiple cells and battery strings. Furthermore, a single microcontroller can simulate the voltage output of multiple individual cells and battery strings, simplifying the circuit structure and reducing costs. By using a multi-channel DAC module to simultaneously output multiple analog voltage signals, and combining this with an isolation operational amplifier to electrically isolate the multiple output voltages from the DAC module, the system achieves simultaneous simulation of multiple individual cells. The output voltage of each cell simulation unit is independent, further simplifying the circuit structure and reducing costs.

[0027] The communication connection between each battery string simulation unit adopts a multi-level series connection method, that is, the first battery string simulation unit 1 is connected to the second battery string simulation unit for power and communication, and so on, the (m-1)th battery string simulation unit is connected to the mth battery string simulation unit for power and communication.

[0028] The communication connection between the microcontroller (MCU) 10 and each battery string analog unit also adopts a multi-stage serial connection. That is, the first-stage control signal is transmitted from the microcontroller 10 to the first digital-to-analog converter (DAC) module 21, which includes control signals for two or more DAC modules. The first DAC module 21 receives its own control signal and forwards the control signals for other DAC modules to the second DAC module, and so on. The (m-1)th DAC module receives its own control signal and forwards the control signals for the mth DAC module to the mth DAC module.

[0029] The communication connection adopts a multi-level series connection, which improves the scalability of the battery string simulation unit. Multiple battery strings can be simulated using only one MCU chip, simplifying the circuit structure and wiring connections, improving compatibility with the battery management system, and making wiring easier. Optionally, a serial bus method can be used to achieve the multi-level series connection, such as a daisy-chain configuration.

[0030] The digital-to-analog converter module includes a digital-to-analog converter chip U1, a first reference voltage source, and a second reference voltage source, such as... Figure 2 As shown. The digital-to-analog converter chip U1 includes a signal input pin DIN, a power supply pin VA, a ground pin GND, two reference voltage pins VREF1 and VREF2, and multiple voltage output pins. The signal input pin DIN is connected to the microcontroller 10 and is used to receive voltage control signals. Optionally, the digital-to-analog converter chip U1 uses a 12-bit DAC chip, which can subdivide the input control signal into 4096 parts. The power supply pin VA is used to receive the first operating voltage VCC1 output by the DC power supply 70. The ground pin GND is used to connect to the first ground GND1. Each voltage output pin generates a voltage that can cover the battery's operating range to simulate battery conditions. Figure 2 The digital-to-analog converter (DAC) chip U1 is shown, comprising eight voltage output pins VOUTA to VOUTH for outputting eight voltage channels. A reference voltage pin is connected to a reference voltage source to acquire a reference voltage signal. Two reference voltage pins, VREF1 and VREF2, are each connected to a reference voltage source. Optionally, the adjustment step size of the DAC chip's output voltage varies with the reference voltage value. When the chip's input reference voltage is 4.096V, the adjustment step size of the DAC chip's output voltage is greater than or equal to 1mV, and the range of each output voltage is 0–4.096V. The SCLK pin of the DAC chip U1 is the clock signal, and the SYNC pin is the chip register clear pin.

[0031] The first and second reference voltage sources have identical structures and are used to provide a reference voltage to the digital-to-analog converter chip U1. The first reference voltage source includes a first voltage regulator chip U2, a first regulating resistor R31, a second regulating resistor R33, a third regulating resistor R34, a first adjustment resistor R26, and a first current-limiting resistor R27. The first voltage regulator chip U2 includes a working voltage pin CA, a ground pin AN, and a voltage output pin REF. The power pin CA receives the first working voltage VCC1 via the first adjustment resistor R26. The power pin CA is connected between R27 and R31. The ground pin AN is used to connect to the first ground GND1. The voltage output pin REF of the first voltage regulator chip U2 is connected to the first ground GND1 via the third regulating resistor R34. This pin is then connected to the first reference voltage VREF1 of the DAC chip U1 via R33, R31, and R27 in sequence.

[0032] The second reference voltage source includes a second voltage regulator chip U3, a fourth adjustment resistor R30, a fifth adjustment resistor R32, a sixth adjustment resistor R35, a second adjustment resistor R29, and a second current-limiting resistor R28. The second voltage regulator chip U3 includes a working voltage pin CA, a ground pin AN, and a voltage output pin REF. The working voltage pin CA receives the first working voltage VCC1 via the second adjustment resistor R29. The working voltage pin CA is connected between R28 and R30. The ground pin AN is used to connect to the first ground GND1. The voltage output pin REF of the second voltage regulator chip U3 is connected to the first ground GND1 via the sixth adjustment resistor R35. This pin is then connected to the second reference voltage VREF2 of the DAC chip U3 via R32, R30, and R28 in sequence.

[0033] The voltage output pin REF of the voltage regulator chip outputs a reference voltage Vb, which, after being adjusted by the first regulating resistor R31, the second regulating resistor R33, and the third regulating resistor R34, outputs a reference voltage Vref to the DAC chip U1.

[0034]

[0035] Where r31, r33, and r34 are the resistance values ​​of R31, R33, and R34, respectively.

[0036] R26 and R29 are used to test the first operating voltage VCC1.

[0037] Since each output of the DAC chip shares a common ground, an isolation operational amplifier U11 is needed to isolate the output voltages of each channel. This isolation operational amplifier isolates the input and output voltages and inputs them differentially to the subsequent operational amplifier U9. The output voltage at pin 4 of the operational amplifier can be adjusted by changing the ratio of resistors R24 and R25. To increase the load-driving capability of the subsequent stage, a voltage follower is designed at the output. The LMV321 chip is used as the input at pin 1 and connected to pins 3 and 4 as the output.

[0038] The cell simulation module is used for signal isolation and voltage adjustment of the received analog voltage signal, isolating the output voltage between different cell simulation modules, and isolating the output voltage of the digital-to-analog converter module from the output voltage of each cell simulation module. Please return Figure 1 Each cell analog module includes an isolated power supply, an isolated operational amplifier (op-amp), a non-inverting op-amp, and a voltage follower. The digital-to-analog converter (DAC) module, isolated op-amp, non-inverting op-amp, and voltage follower are connected sequentially. The isolated op-amp isolates the voltages output from the DAC module, ensuring that each output voltage has a different ground. The non-inverting op-amp is connected to the output of the isolated op-amp and amplifies and regulates the output voltage to achieve the set value. The voltage follower has low output impedance, which improves the drive capability of the output without changing the voltage.

[0039] The cell simulation module is also used for electrical isolation of the DC power supply, isolating the output voltage between the DC power supply 70 and each cell simulation module. The isolation power supply is electrically connected to the DC power supply, the isolation operational amplifier, the non-inverting operational amplifier, and the voltage follower, respectively, to provide a second operating voltage VCC2 to each component. The isolation operational amplifier is also connected to the DC power supply 70.

[0040] like Figure 1 As shown, the first cell simulation module 111 includes a first isolated power supply 311, a first isolated operational amplifier 411, a first non-inverting operational amplifier 511, and a first voltage follower 61n. The second cell simulation module 112 includes a second isolated power supply 312, a second isolated operational amplifier 412, a second non-inverting operational amplifier 512, and a second voltage follower 612. Similarly, the nth cell simulation module 11n includes an nth isolated power supply 31n, an nth isolated operational amplifier 41n, an nth non-inverting operational amplifier 51n, and an nth voltage follower 61n. B11, B12…B1n are the output interfaces of each cell simulation module, used to output the voltage of each individual cell. Interfaces B11, B12…B1n can also be combined into one. The cell simulation modules are connected in series, that is, the negative terminal of the first cell simulation module 111 is connected to the positive terminal of the second cell simulation module 112, and the negative terminal of the (n-1)th cell simulation module is connected to the positive terminal of the nth cell simulation module. In each battery string simulation unit, the positive terminal of the first cell simulation module 111 and the negative terminal of the nth cell simulation module constitute the output voltage of the battery string simulation unit.

[0041] The DC power supply 70 is connected to the microcontroller (MCU) 10, the digital-to-analog converter module 21 in the first battery string analog unit 1, and each isolated power supply to provide them with DC power. Figure 3 As shown, the isolated power supply is used to output a voltage that is electrically isolated from the DC power supply. The output voltages of different isolated power supplies are also electrically isolated. The isolated power supply uses an isolation chip and employs digital circuitry to simulate the battery cells and battery strings. Compared to traditional analog circuit methods, the simplified circuit structure significantly reduces the device size and makes it more convenient to use. Figure 3As shown, the isolation chip U8 includes a voltage input terminal Vin+, a voltage output terminal Vout+, a first ground terminal Vin-, and a second ground terminal Vout-. Electrical isolation between the power input terminals (Vin+, Vin-) and the power output terminals (Vout+, Vout-) is achieved through sampling optical coupling or magnetic coupling. The voltage input terminal Vin+ is connected to the DC power supply 70 to receive its output first operating voltage VCC1, and the voltage output terminal Vout+ is used to output the second operating voltage VCC2. The power input and power output terminals of each isolation power supply are not grounded. The first ground terminal Vin- and the second ground terminal Vout- are connected to the first ground GND1 and the second ground GND2, respectively. The positive power output terminal Vout+ is also connected to a light-emitting diode LED4 as a power indicator to indicate the power supply's operating status. R22 is the third current-limiting resistor. The first capacitor C26 serves as a voltage regulator.

[0042] like Figure 4 As shown, the isolation operational amplifier uses isolation operational amplifier chip U9, including a first operating voltage input terminal VDD1, a second operating voltage input terminal VDD2, a signal input terminal VIN, a signal output terminal VOUTP, an enable terminal SHTDN, a signal ground terminal VOUTN, a first ground terminal GND1, and a second ground terminal GND2. The first operating voltage input terminal VDD1 is connected to the output terminal of DC power supply 70 to receive the first operating voltage VCC1. The second operating voltage input terminal VDD2 is connected to the output terminal of isolation chip U8 to receive the second operating voltage VCC2. The signal input terminal VIN is connected to one of the outputs (VOUTA) of the digital-to-analog converter chip. The signal output terminal VOUTP is connected to the non-inverting input terminal of non-inverting operational amplifier U5 to output the isolated input signal (VOUTA). The first ground terminal GND1 and the second ground terminal GND2 are connected to the first ground GND1 and the second ground GND2, respectively. The enable terminal SHTDN and the signal ground terminal VOUTN are connected to the first ground GND1 and the second ground GND2, respectively.

[0043] The power supply terminal V+ of the non-inverting operational amplifier U5 is connected to the voltage output terminal of the isolated power supply to obtain the second operating voltage VCC2. The ground terminal of the non-inverting operational amplifier U5 is connected to the second ground GND2. The output terminal of the non-inverting operational amplifier U5 is connected to the non-inverting input terminal of the voltage follower U6 via the matching resistor R23. The output terminal of the non-inverting operational amplifier U5 is connected to the second ground GND2 via the seventh adjusting resistor R24 ​​and the eighth adjusting resistor R25. The inverting input terminal of the non-inverting operational amplifier U5 is connected between resistors R24 and R25. The output voltage value of the non-inverting operational amplifier U5 is adjusted by R24 and R25 to reach the set value. The matching resistor R23 is used for impedance matching between the non-inverting operational amplifier U5 and the voltage follower U6.

[0044] The power supply terminal V+ of voltage follower U6 is connected to the voltage output terminal of DC power supply 70 to obtain the second operating voltage VCC2. The ground terminal GND of voltage follower U6 is connected to the second ground GND2. The inverting input terminal of voltage follower U6 is directly connected to its output terminal. The output terminal of voltage follower U6 is connected to interface B11, etc., to output the cell analog voltage BOUT.

[0045] The first operating voltage input terminal VDD1 of the non-inverting operational amplifier U5, the power supply terminal V+ of the non-inverting operational amplifier U5, and the power supply terminal V+ of the voltage follower U6 are connected to the second ground GND2 through the second capacitor C23, the third capacitor C24, and the fourth capacitor C25, respectively, which serves to filter and decouple.

[0046] The battery string simulation unit in this embodiment uses a multi-channel digital-to-analog converter (DAC) to simultaneously output multiple analog voltage signals, thereby simulating multiple individual battery cells. This simplifies the circuit structure and reduces costs. The cell simulation module uses an isolation operational amplifier (OPA) to electrically isolate the multiple output voltages from the DAC. Simultaneously, an isolated power supply powers the OPA, electrically isolating the output voltage of the DC power supply 70 from the output voltage of the DAC. This enables the simultaneous simulation of the output voltage of multiple individual battery cells, providing the conditions for multiple cell simulation modules to be connected in series to simulate the output voltage of a battery string. A voltage follower is used to improve the load-carrying capacity, simulating the driving capability of a real battery cell. By connecting the output voltages of multiple cell simulation modules in series, the simulation of the battery string's output voltage is achieved.

[0047] The relevant content of each unit in this embodiment can be referred to the relevant content of the units with the same reference numerals in any of the foregoing embodiments, and will not be repeated here.

[0048] The technical features of the above embodiments can be combined in any way. For the sake of brevity, not all possible combinations of the technical features in the above embodiments are described. However, as long as there is no contradiction in the combination of these technical features, they should be considered to be within the scope of this specification.

[0049] The embodiments described above are merely illustrative of several implementation methods of this application, and while the descriptions are specific and detailed, they should not be construed as limiting the scope of the invention patent. It should be noted that those skilled in the art can make various modifications and improvements without departing from the concept of this application, and these all fall within the protection scope of this application. Therefore, the protection scope of this application should be determined by the appended claims.

Claims

1. A multi-channel controllable battery simulation device, characterized in that, It includes a DC power supply, a microcontroller, and at least one battery string simulation unit; the battery string simulation unit is used to simulate the output voltage of the battery string, and it includes a digital-to-analog converter module and multiple cell simulation modules connected in series. The microcontroller is connected to the digital-to-analog converter module and is used to generate multiple controllable digital voltage signals and output them to the digital-to-analog converter module. The digital-to-analog conversion module includes multiple analog voltage output channels, each analog voltage output channel being connected to multiple cell simulation modules, for converting the received voltage digital signal into multiple analog voltage signals and outputting them to the multiple cell simulation modules; The cell simulation module is used to isolate and adjust the received analog voltage signal; each cell simulation module includes an isolated power supply, an isolated operational amplifier, a non-inverting operational amplifier, and a voltage follower, and the digital-to-analog converter module, the isolated operational amplifier, the non-inverting operational amplifier, and the voltage follower are connected in sequence; The DC power supply is connected to the microcontroller and the at least one battery string simulation unit, respectively, to provide them with operating voltage.

2. The multi-channel controllable battery simulation device according to claim 1, characterized in that, The cell simulation module is also used to electrically isolate the DC power supply. The isolated power supply is connected to the DC power supply, the isolated operational amplifier, the non-inverting operational amplifier, and the voltage follower, respectively. The isolated operational amplifier is also connected to the DC power supply.

3. The multi-channel controllable battery simulation device according to claim 1, characterized in that, It includes two or more battery string simulation units, and the microcontroller is connected to different battery string simulation units in a multi-level series manner.

4. The multi-channel controllable battery simulation device according to claim 1, characterized in that, The isolated power supply includes an isolation chip, which includes a voltage input terminal, a voltage output terminal, a first ground terminal, and a second ground terminal. The voltage input terminal is used to receive a first operating voltage output by the DC power supply, and the voltage output terminal is used to output a second operating voltage. The first ground terminal and the second ground terminal are not grounded.

5. The multi-channel controllable battery simulation device according to claim 1, characterized in that, The digital-to-analog conversion module includes a digital-to-analog conversion chip and a reference voltage source. The reference voltage source is connected to the reference voltage terminal of the digital-to-analog conversion chip and is used to provide a reference voltage to the digital-to-analog conversion chip.

6. The multi-channel controllable battery simulation device according to claim 5, characterized in that, The reference voltage source includes a voltage regulator chip. The power supply pin of the voltage regulator chip is connected to a DC power supply via a first adjustment resistor to receive a first operating voltage. The voltage output pin of the voltage regulator chip is connected to a first ground via a third adjustment resistor. The voltage output pin is connected to the reference voltage terminal of the digital-to-analog converter chip via a second adjustment resistor, a first adjustment resistor, and a current-limiting resistor in sequence. The power supply pin is connected between the current-limiting resistor and the second adjustment resistor. The ground pin of the voltage regulator chip is connected to the first ground.

7. The multi-channel controllable battery simulation device according to claim 4, characterized in that, The digital-to-analog converter module includes a digital-to-analog converter chip, and the isolation operational amplifier includes an isolation operational amplifier chip. The isolation operational amplifier chip includes a first operating voltage input terminal, a second operating voltage input terminal, a signal input terminal, a signal output terminal, a first ground terminal, and a second ground terminal. The first operating voltage input terminal is connected to the DC power supply output terminal to receive a first operating voltage. The second operating voltage input terminal is connected to the voltage output terminal of the isolation chip to receive a second operating voltage. The signal input terminal is connected to one of the outputs of the digital-to-analog converter chip, and the signal output terminal is connected to the non-inverting input terminal of the non-inverting operational amplifier to output an isolated voltage signal. The first ground terminal and the second ground terminal are respectively connected to a first ground and a second ground.

8. The multi-channel controllable battery simulation device according to claim 7, characterized in that, The non-inverting operational amplifier includes a power supply terminal, a ground terminal, a non-inverting input terminal, an inverting input terminal, and a signal output terminal. The power supply terminal is connected to the voltage output terminal of the isolation power supply to obtain the second operating voltage. The ground terminal of the non-inverting operational amplifier is connected to a second ground. The output terminal of the non-inverting operational amplifier is connected to the non-inverting input terminal of the voltage follower. The output terminal of the non-inverting operational amplifier is connected to the second ground via a seventh adjustment resistor and an eighth adjustment resistor. The inverting input terminal of the non-inverting operational amplifier is connected between the seventh adjustment resistor and the eighth adjustment resistor.

9. The multi-channel controllable battery simulation device according to claim 8, characterized in that, The voltage follower includes a power supply terminal, a ground terminal, a non-inverting input terminal, an inverting input terminal, and an output terminal. The power supply terminal of the voltage follower is connected to the voltage output terminal of the isolated power supply to obtain the second operating voltage. The ground terminal of the voltage follower is connected to a second ground. The inverting input terminal of the voltage follower is directly connected to its output terminal. The output terminal of the voltage follower is connected to an output interface.

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