A battery simulator capable of accurately simulating steady-state characteristics and transient characteristics of a battery

Abstract

This invention provides a battery simulator that can accurately simulate the steady-state and transient characteristics of a battery. The simulator includes a main control module, a battery characteristic simulation module, and a sampling module. The battery characteristic simulation module outputs to an adjustable load and includes a steady-state characteristic simulation branch and at least one transient characteristic simulation branch. The transient characteristic simulation branch is connected to or disconnected from the simulation circuit via a switch to simulate sudden changes in battery output voltage during transient states. Both the steady-state and transient characteristic simulation branches include voltage regulation circuits. The main control module adjusts the output voltage of the steady-state and transient characteristic simulation branches by controlling the voltage regulation circuits. This invention can simulate the discharge characteristics of a battery when its output voltage changes suddenly during transient states. The main control module can also adjust the adjustable load, thereby simulating the discharge characteristics of a battery according to a specific load change pattern.

Description

Technical Field

[0001] This invention relates to the field of battery simulator technology, and specifically to a battery simulator that can accurately simulate the steady-state and transient characteristics of a battery. Background Technology

[0002] Batteries are a common power source used in numerous experiments. However, directly using battery prototypes for research is costly in terms of both purchase and maintenance, and carries the risk of damage during extreme testing conditions. Using battery simulators to accurately simulate battery output characteristics and then replacing batteries in experiments can solve these problems, significantly reducing research costs and accelerating progress. While many battery simulators are available on the market, most only offer simple steady-state charging and discharging capabilities and cannot effectively simulate the transient characteristics when switching high-power loads. For example, when the load suddenly increases, the battery experiences a brief voltage drop in the output voltage, lasting in μs or even nanoseconds. Existing battery simulators, relying solely on rectifiers and DC / DC converters, cannot simulate this voltage fluctuation.

[0003] content

[0004] This invention aims to solve

[0005] To address the above problems, this invention provides a battery simulator that can accurately simulate the steady-state and transient characteristics of a battery.

[0006] This invention provides a battery simulator capable of accurately simulating the steady-state and transient characteristics of a battery, comprising a main control module, a battery characteristic simulation module, and a sampling module. The main control module adjusts the output voltage of the battery characteristic simulation module via control signals. The sampling module collects the output voltage and output current of the battery characteristic simulation module and transmits them to the main control module. Its key feature is:

[0007] The battery characteristic simulation module is connected to an adjustable load and outputs to the adjustable load;

[0008] The battery characteristic simulation module includes a steady-state characteristic simulation branch and at least one transient characteristic simulation branch. The transient characteristic simulation branch is connected to or disconnected from the simulation circuit by a switching switch to simulate the sudden change in battery output voltage during transient conditions.

[0009] Both the steady-state characteristic simulation branch and the transient characteristic simulation branch include a voltage regulation circuit. The main control module adjusts the output voltage of the steady-state characteristic simulation branch and the transient characteristic simulation branch by controlling the voltage regulation circuit.

[0010] Preferably, the adjustable load consists of a Buck converter connected in series with a fixed load.

[0011] Preferably, the switching switch includes an H-bridge switching switch.

[0012] Preferably, the battery characteristic simulation module further includes a constant voltage output branch.

[0013] Preferably, isolated DC / DC converters are provided in the steady-state characteristic simulation branch, the transient characteristic simulation branch, and the constant voltage output branch.

[0014] Preferably, the sampling module includes an ADC sampling device with a sampling frequency exceeding 1MHz.

[0015] Preferably, the battery simulator also includes an AC power supply for providing operating voltage to the battery characteristic simulation module.

[0016] Preferably, the display module is electrically connected to the main control module and displays the electrical parameters of the battery simulator.

[0017] Preferably, the battery simulator also includes a host computer, which is electrically connected to the main control module and inputs the battery parameters to be simulated into the main control module.

[0018] Compared with the prior art, the present invention has the following advantages:

[0019] The battery simulator provided by this invention can accurately simulate the steady-state and transient characteristics of a battery. It can not only simulate the steady-state characteristics but also control the switching in and out of the transient characteristic simulation branch through the main control module to simulate the discharge characteristics when the battery output voltage changes abruptly during transient states. The main control module can also adjust the adjustable load, thereby simulating the battery's discharge characteristics according to specific load change patterns. This battery simulator, which accurately simulates both steady-state and transient characteristics, overcomes the shortcomings of existing devices in simulating the discharge characteristics when the battery voltage changes abruptly, thus improving the accuracy of the simulation. Attached Figure Description

[0020] Figure 1 The diagram shown is a structural block diagram of a battery simulator in one embodiment;

[0021] Figure 2 The diagram shown is a circuit diagram of a battery characteristic simulation module in one embodiment.

[0022] Figure 3 The diagram shown is a circuit diagram of an H-bridge voltage regulator circuit in one embodiment.

[0023] Figure 4 The diagram shown is a circuit diagram of an H-bridge switching switch in one embodiment.

[0024] Figure 5 The diagram shown is a circuit diagram of an isolated DC / DC converter in one embodiment.

[0025] Figure 6 The diagram shown is a circuit diagram of an adjustable load in one embodiment.

[0026] Figure 7 The diagram shown is a control flowchart of a battery simulator in one embodiment;

[0027] The reference numerals in the attached figures are explained as follows:

[0028] 1-Main control module; 2-Battery characteristic simulation module; 3-Sampling module; 4-Adjustable load; 5-AC power supply; 6-Display module; 7-Host computer. Detailed Implementation

[0029] To make the objectives, advantages, and features of the present invention clearer, the following detailed description, in conjunction with the accompanying drawings, provides a battery simulator capable of accurately simulating the steady-state and transient characteristics of a battery. It should be noted that the drawings are all in a very simplified form and use non-precise proportions, and are only used to facilitate and clarify the explanation of the embodiments of the present invention.

[0030] Please see Figure 1 and Figure 2 This embodiment provides a battery simulator that can accurately simulate the steady-state and transient characteristics of a battery, including a main control module 1, a battery characteristic simulation module 2, and a sampling module 3. The main control module 1 adjusts the output voltage of the battery characteristic simulation module 2 through control signals. The sampling module 3 is used to collect the output voltage and output current of the battery characteristic simulation module 2 and transmit them to the main control module 1. The key feature is that:

[0031] The battery characteristic simulation module 2 is connected to the adjustable load 4 and outputs to the adjustable load 4;

[0032] The battery characteristic simulation module 2 includes a steady-state characteristic simulation branch and at least one transient characteristic simulation branch. The transient characteristic simulation branch is connected to or disconnected from the simulation circuit by a switching switch to simulate the sudden change in battery output voltage during transient conditions.

[0033] Both the steady-state characteristic simulation branch and the transient characteristic simulation branch include a voltage regulation circuit. The main control module 1 adjusts the output voltage of the steady-state characteristic simulation branch and the transient characteristic simulation branch by controlling the voltage regulation circuit.

[0034] In one embodiment, the battery characteristic simulation module 2 further includes a constant voltage output branch. The constant voltage output branch and the steady-state characteristic simulation branch together constitute the voltage output of the load under normal conditions, and the change in battery charge can be simulated by changing the output voltage of the steady-state characteristic simulation branch.

[0035] In one embodiment, the battery simulator further includes an AC power supply 5, which provides operating voltage to the battery characteristic simulation module 2. The AC power supply 5 is connected to a 375V DC voltage input via a PFC module, and this DC voltage is further converted into the voltage required for the experiment.

[0036] In one embodiment, the battery simulator further includes a display module 6, which is electrically connected to the main control module 1 and displays the electrical parameters of the battery simulator.

[0037] In one embodiment, the battery simulator further includes a host computer 7, which is electrically connected to the main control module 1 and inputs the battery parameters to be simulated into the main control module 1. The host computer 7 can also perform operations such as parameter calibration, upgrades, and curve plotting.

[0038] In one embodiment, the voltage regulation circuit of the steady-state characteristic simulation branch includes an H-bridge voltage regulation circuit. See also... Figure 3 , Figure 3 The diagram shows the circuit diagram of the H-bridge voltage regulator circuit. When one pair of switching elements on the diagonal is turned on and the other pair is turned off, current flows from one side to the other, driving the load to rotate in a certain direction. When the other pair of switching elements on the diagonal is turned on and the original pair is turned off, the current flows in the opposite direction, driving the load to rotate in the opposite direction. When both switching elements on the same side are turned on or off simultaneously, the current is cut off, and the load stops rotating. When a PWM waveform signal is input to one of the switching elements while the other remains on or off, the current changes periodically, thereby changing the average voltage and speed of the load. The H-bridge voltage regulator circuit has advantages such as simple structure, convenient control, and the ability to achieve forward and reverse rotation and speed regulation.

[0039] In one embodiment, the voltage regulation circuit of the transient characteristic simulation branch includes a Buck voltage regulation circuit, which is a basic circuit in the art and will not be described in detail here. The transient characteristic simulation branch also includes a switching switch, which includes an H-bridge switching switch. Please refer to [link to relevant documentation]. Figure 4 , Figure 4The diagram shows the circuit diagram of the H-bridge switching switch. The Buck voltage regulator circuit adjusts the output voltage amplitude, and the H-bridge switching switch controls whether this module is connected to or disconnected from the series circuit to simulate sudden changes in battery output voltage during transients. Multiple voltage drops within a short period can be simulated by adding one or more battery transient characteristic simulation modules. When both upper arms or both lower arms of the H-bridge switching switch are simultaneously conducting, the output of the Buck voltage regulator circuit in the battery transient characteristic simulation module is unloaded and not connected to the circuit; the two switching transistors only provide a current path. When it is necessary to simulate sudden changes in battery output voltage, the H-bridge switching switch is activated, and the outputs of the LLC circuit and the Buck voltage regulator circuit are instantaneously connected to the circuit, causing a sudden change in voltage across the load.

[0040] In one embodiment, isolated DC / DC converters are provided in the steady-state characteristic simulation branch, the transient characteristic simulation branch, and the constant voltage output branch. The isolated DC / DC converter can convert DC voltage from one level to another, and an isolation transformer is provided between the input and output. The isolation transformer provides safety, noise suppression, and voltage transformation functions. Please refer to [link to relevant documentation]. Figure 5 , Figure 5 The circuit diagram of the isolated DC / DC converter is shown. This isolated DC / DC converter adopts an FB-LLC (Full bridge LLC) resonant converter topology, which meets the design requirements. To improve system efficiency and achieve stable constant voltage output, the LLC resonant converter operates in fixed-frequency mode. In this embodiment, after passing through the isolated DC / DC converter, the voltages of the steady-state characteristic simulation branch, the transient characteristic simulation branch, and the constant voltage output branch are reduced to 15V, 24V, and 15V, respectively.

[0041] Please see Figure 6 In one embodiment, the adjustable load 4 consists of a Buck converter connected in series with a fixed load. By changing the duty cycle of the Buck converter, the size of the equivalent load can be changed, allowing the battery to discharge according to a specific load variation pattern.

[0042] In one embodiment, preferably, the sampling module 3 includes an ADC sampling device with a sampling frequency exceeding 1MHz, thereby ensuring that a sufficient number of output voltage and output current samples can be collected in a short period of time during voltage fluctuations.

[0043] Please see Figure 7 , Figure 7The diagram shows the control flowchart of the battery simulator. The control strategy adopts dual closed-loop control of voltage and current. The load voltage is the outer loop, and the inductor current is the inner loop. The voltage command value is calculated based on the battery characteristics and the load current. The host computer sends the battery characteristic parameters through CAN communication. The voltage command value is processed by PI to obtain the current command value. The difference between the current command value and the actual sampled inductor current value is then processed by PI again to obtain the duty cycle command. By adding the duty cycle output by the inner current loop to the corresponding duty cycle change calculated from the load current change, the dynamic response of the system can be improved, and the control requirements can be met more quickly.

[0044] In summary, the battery simulator provided by this invention, which can accurately simulate both steady-state and transient characteristics of a battery, not only simulates steady-state characteristics but also, through the main control module, controls the switching in and out of the transient characteristic simulation branch to simulate the discharge characteristics when the battery output voltage changes abruptly during transient states. Furthermore, the main control module can adjust the adjustable load, thereby simulating the battery's discharge characteristics according to specific load variation patterns. This battery simulator, which accurately simulates both steady-state and transient characteristics of a battery, overcomes the shortcomings of existing devices in simulating the discharge characteristics when the battery voltage changes abruptly, thus improving the accuracy of the simulation.

[0045] Furthermore, it is understood that although the present invention has been disclosed above with reference to preferred embodiments, the above embodiments are not intended to limit the present invention. For any person skilled in the art, many possible variations and modifications can be made to the technical solutions of the present invention using the disclosed technical content, or equivalent embodiments with equivalent changes, without departing from the scope of the present invention. Therefore, any simple modifications, equivalent changes, and modifications made to the above embodiments based on the technical essence of the present invention without departing from the content of the present invention are still within the scope of protection of the present invention. It should also be understood that the terminology described herein is used only to describe specific embodiments and is not intended to limit the scope of the present invention. It must be noted that the singular forms “a,” “an,” and “the” used herein and in the appended claims include plural bases unless the context clearly indicates the opposite. All conjunctions used should be understood in the broadest sense. Therefore, the word “or” should be understood to have a logical “or” definition, not a logical “XOR” definition, unless the context clearly indicates the opposite. The structures described herein will be understood to also refer to functional equivalents of the structures.

Claims

1. A battery simulator capable of accurately simulating the steady-state and transient characteristics of a battery, comprising at least a main control module, a battery characteristic simulation module, and a sampling module, wherein the main control module adjusts the output voltage of the battery characteristic simulation module via control signals, and the sampling module is used to collect the output voltage and output current of the battery characteristic simulation module and transmit them to the main control module, characterized in that: The battery characteristic simulation module is connected to an adjustable load and outputs to the adjustable load; The battery characteristic simulation module includes a steady-state characteristic simulation branch and at least one transient characteristic module. The simulated branch, which simulates transient characteristics, is connected to or disconnected from the simulation circuit by a switching switch to simulate the sudden change in battery output voltage during transients. Both the steady-state characteristic simulation branch and the transient characteristic simulation branch include a voltage regulating circuit. The main control module adjusts the output voltage of the steady-state characteristic simulation branch and the transient characteristic simulation branch by controlling the voltage regulating circuit. The switching switch includes an H-bridge switching switch.

2. The battery simulator as described in claim 1, which can accurately simulate the steady-state and transient characteristics of a battery, is characterized in that, The adjustable load consists of a Buck converter connected in series with a fixed load.

3. The battery simulator as described in claim 1, which can accurately simulate the steady-state and transient characteristics of a battery, is characterized in that, The battery characteristic simulation module also includes a constant voltage output branch.

4. The battery simulator as described in claim 3, which can accurately simulate the steady-state and transient characteristics of a battery, is characterized in that, An isolated DC / DC converter is provided in the steady-state characteristic simulation branch, the transient characteristic simulation branch, and the constant voltage output branch.

5. The battery simulator as described in claim 1, capable of accurately simulating the steady-state and transient characteristics of a battery, characterized in that, The sampling module includes an ADC sampling device, and the sampling frequency of the ADC sampling device exceeds 1MHz.

6. The battery simulator as described in claim 1, capable of accurately simulating the steady-state and transient characteristics of a battery, characterized in that, The battery simulator also includes an AC power supply for providing operating voltage to the battery characteristic simulation module.

7. The battery simulator as described in claim 1, capable of accurately simulating the steady-state and transient characteristics of a battery, characterized in that, The battery simulator also includes a display module, which is electrically connected to the main control module and displays the electrical parameters of the battery simulator.

8. The battery simulator as described in claim 1, capable of accurately simulating the steady-state and transient characteristics of a battery, characterized in that, The battery simulator also includes a host computer, which is electrically connected to the main control module and inputs the battery parameters to be simulated into the main control module.

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