Battery pack simulator

Abstract

The invention discloses a battery pack simulator, and the simulator comprises a power supply module which is used for outputting a first voltage signal; the voltage conversion module is electrically connected with the power supply module and is used for receiving the first voltage signal and converting the first voltage signal into a second voltage signal; the voltage conversion module comprises a voltage reduction unit and a control unit; the voltage reduction unit comprises a first gallium nitride metal oxide semiconductor field effect transistor and a second gallium nitride metal oxide semiconductor field effect transistor; the plurality of analog cells are arranged in parallel, are electrically connected with the voltage conversion module and are used for receiving the second voltage signal and converting the second voltage signal into an output voltage signal; each simulation cell comprises a resonance unit; the resonance unit comprises a third gallium nitride metal oxide semiconductor field effect transistor and a fourth gallium nitride metal oxide semiconductor field effect transistor. By adopting the technical means, the battery pack simulator is simple and compact in structure and high in working efficiency.

Description

Technical Field

[0001] This invention relates to the field of battery pack technology, and more particularly to a battery pack simulator. Background Technology

[0002] The primary function of a battery pack simulator is to simulate the voltage of actual battery cells. Battery pack simulators are widely used in the development and verification of battery management systems and other fields.

[0003] Currently, battery pack simulators typically use Buck transformers and resonant circuits to step down the voltage signal supplied by the power source. However, conventional Buck transformers and resonant circuits have complex structures and low efficiency. Summary of the Invention

[0004] This invention provides a battery pack simulator to improve the structure of the battery pack simulator and increase its working efficiency.

[0005] This invention provides a battery pack simulator, comprising:

[0006] The power supply module is used to output the first voltage signal;

[0007] A voltage conversion module, electrically connected to the power supply module, is used to receive the first voltage signal and convert the first voltage signal into a second voltage signal; the voltage value of the second voltage signal is less than the voltage value of the first voltage signal; the voltage conversion module includes a step-down unit and a control unit; the step-down unit includes a first gallium nitride metal oxide semiconductor field-effect transistor and a second gallium nitride metal oxide semiconductor field-effect transistor; the control terminals of the first gallium nitride metal oxide semiconductor field-effect transistor and the second gallium nitride metal oxide semiconductor field-effect transistor are both electrically connected to the first control terminal of the control unit, and the input terminal of the first gallium nitride metal oxide semiconductor field-effect transistor is electrically connected to the output terminal of the second gallium nitride metal oxide semiconductor field-effect transistor;

[0008] Multiple analog cells connected in parallel are electrically connected to the step-down unit to receive the second voltage signal and convert it into an output voltage signal. The voltage value of the output voltage signal is less than that of the second voltage signal. Each analog cell includes a resonant unit. The resonant unit includes a third gallium nitride metal-oxide-semiconductor field-effect transistor (GaNMT) and a fourth GaNMT. The control terminals of the third and fourth GaNMTs are electrically connected to the second control terminal of the control unit. The input terminal of the third GaNMT is electrically connected to the output terminal of the fourth GaNMT.

[0009] Optionally, the first gallium nitride metal oxide semiconductor field-effect transistor and the second gallium nitride metal oxide semiconductor field-effect transistor are integrated on the first chip;

[0010] The third gallium nitride metal oxide semiconductor field-effect transistor and the fourth gallium nitride metal oxide semiconductor field-effect transistor are integrated on the second chip.

[0011] Optionally, the voltage conversion module further includes a voltage divider unit; the voltage divider unit includes a first resistor and a second resistor;

[0012] The voltage conversion module also includes a first inductor;

[0013] The first end of the first inductor is electrically connected to the input terminal of the first gallium nitride metal oxide semiconductor field-effect transistor and the output terminal of the second gallium nitride metal oxide semiconductor field-effect transistor; the second end of the first inductor is electrically connected to the first end of the first resistor, the second end of the first resistor and the first end of the second resistor are both electrically connected to the sampling terminal of the control unit, and the second end of the second resistor is electrically connected to the sampling terminal and the ground terminal of the control unit.

[0014] The output terminal of the first gallium nitride metal oxide semiconductor field-effect transistor is electrically connected to the positive terminal of the power supply module, and the input terminal of the second gallium nitride metal oxide semiconductor field-effect transistor is electrically connected to the negative terminal and the ground terminal of the power supply module.

[0015] Optionally, the resonant unit further includes a second inductor, a transformer, a first capacitor, a first diode, a second diode, a second capacitor, and a third inductor;

[0016] The output terminal of the third gallium nitride metal oxide semiconductor field-effect transistor is electrically connected to the second terminal of the first inductor; the input terminal of the third gallium nitride metal oxide semiconductor field-effect transistor is electrically connected to the output terminal of the fourth gallium nitride metal oxide semiconductor field-effect transistor and the first terminal of the second inductor; the second terminal of the second inductor is electrically connected to the first terminal of the primary winding side of the transformer, and the second terminal of the primary winding side of the transformer is electrically connected to the negative terminal of the power supply module and the input terminal of the fourth gallium nitride metal oxide semiconductor field-effect transistor through the first capacitor;

[0017] The first end of the secondary winding side of the transformer is electrically connected to the positive terminal of the first diode, and the second end of the secondary winding side of the transformer is electrically connected to the positive terminal of the second diode; the negative terminals of both the first and second diodes are electrically connected to the first end of the second capacitor; the middle end of the secondary winding side of the transformer is electrically connected to the first end of the third inductor, and the second end of the third inductor is electrically connected to the second end of the second capacitor.

[0018] Optionally, the turns ratio of the primary winding to the secondary winding is n:1;

[0019] The resistance of the first resistor is R1, and the resistance of the second resistor is R2; where R1 / (R1+R2) = 1 / n.

[0020] Optionally, the battery pack simulator further includes: a mode switching module;

[0021] The mode switching module includes a third resistor, a sliding rheostat, a first transistor, a fourth resistor, a third capacitor, a manual button, and a fifth resistor;

[0022] The first end of the third resistor is electrically connected to the power supply module, and the second end of the third resistor is electrically connected to the sliding end of the variable resistor and the sampling end of the control unit; the fixed end of the variable resistor is electrically connected to the input end of the first transistor, the control end of the first transistor is electrically connected to the first end of the fourth resistor, and the output end of the first transistor is electrically connected to the first end of the third capacitor and the ground end; the second end of the third capacitor and the second end of the fourth resistor are electrically connected to the first end of the fifth resistor and the reset end of the control unit through the manual button, and the second end of the fifth resistor is electrically connected to the power supply end of the control unit;

[0023] The host computer is electrically connected to the input terminal of the control unit.

[0024] Optionally, the battery pack simulator further includes: a voltage sampling module and an alarm module;

[0025] The sampling terminal of the voltage sampling module is electrically connected to the output terminal of each of the simulated cells in a one-to-one correspondence, and is used to collect the current voltage value output by each of the simulated cells.

[0026] The comparison terminal of the control unit is electrically connected to the output terminal of the voltage sampling module, and the comparison terminal of the control unit is also electrically connected to the output terminal of the power management module; the sampling terminal of the power management module is electrically connected to the output terminal of each of the analog cells one by one, for collecting the target voltage value output by each of the analog cells; the alarm signal output terminal of the control unit is electrically connected to the alarm module.

[0027] The control unit is used to receive the current voltage value and the target voltage value output by each of the simulated cells, and output an alarm signal to the alarm module according to the current voltage value, the target voltage value and the preset voltage difference output by each of the simulated cells.

[0028] Optionally, the alarm module includes a sixth resistor and an alarm indicator light;

[0029] The first end of the sixth resistor is electrically connected to the alarm signal output terminal of the control unit, the second end of the sixth resistor is electrically connected to one end of the alarm indicator light, and the other end of the alarm indicator light is electrically connected to the ground terminal.

[0030] Optionally, the battery pack simulator further includes: an isolation chip;

[0031] The output terminal of the voltage acquisition module is electrically connected to the comparison terminal of the control unit through the isolation chip.

[0032] Optionally, the power supply module includes a regulated power supply, a first power conversion unit, and a second power conversion unit;

[0033] The regulated power supply is electrically connected to the input terminal of the first power conversion unit and the input terminal of the second power conversion module;

[0034] The output terminal of the first power conversion module is electrically connected to the power terminal of the mode switching module, and the output terminal of the second power conversion module is electrically connected to the power terminal of the control unit.

[0035] The battery pack simulator provided in this embodiment of the invention includes a voltage conversion module for receiving a first voltage signal output from a power supply module and converting the first voltage signal into a second voltage signal to achieve a step-down function. Multiple simulated battery cells connected in parallel are used to simulate the voltage of multiple battery cells, and each simulated battery cell is electrically connected to the voltage conversion module to receive the second voltage signal and convert it into an output voltage signal to further achieve the step-down function. The voltage conversion module includes a step-down unit and a control unit; the step-down unit includes a first gallium nitride metal-oxide-semiconductor field-effect transistor and a second gallium nitride metal-oxide-semiconductor field-effect transistor, i.e., a half-bridge gallium nitride metal-oxide-semiconductor field-effect transistor is used as part of the step-down unit, thus simplifying the step-down unit structure. Furthermore, each simulated battery cell includes a resonant unit; the resonant unit includes a third gallium nitride metal-oxide-semiconductor field-effect transistor and a fourth gallium nitride metal-oxide-semiconductor field-effect transistor, i.e., a half-bridge gallium nitride metal-oxide-semiconductor field-effect transistor is used as part of the resonant unit, thus simplifying the resonant unit structure, thereby simplifying the structure of the battery pack simulator, reducing the number of components used, and increasing working efficiency. Attached Figure Description

[0036] To more clearly illustrate the technical solutions in the embodiments of the present invention, the accompanying drawings used in the description of the embodiments of the present invention will be briefly introduced below. Obviously, the accompanying drawings described below are only some embodiments of the present invention. For those skilled in the art, other drawings can be obtained based on the content of the embodiments of the present invention and these drawings without creative effort.

[0037] Figure 1 This is a schematic diagram of the structure of a battery pack simulator provided in an embodiment of the present invention;

[0038] Figure 2 A schematic diagram of the electrical connection between a first voltage conversion module and a simulated battery cell provided in an embodiment of the present invention;

[0039] Figure 3 This is a schematic diagram of the electrical connection between a second voltage conversion module and a simulated battery cell provided in an embodiment of the present invention;

[0040] Figure 4 An electrical schematic diagram of a mode switching module and a control unit provided in an embodiment of the present invention;

[0041] Figure 5 This is a schematic diagram of the electrical principle of an alarm module and a control unit provided in an embodiment of the present invention. Detailed Implementation

[0042] The present invention will now be described in further detail with reference to the accompanying drawings and embodiments. It should be understood that the specific embodiments described herein are merely illustrative of the invention and not intended to limit it. Furthermore, it should be noted that, for ease of description, the accompanying drawings show only the parts relevant to the present invention, and not all of the structures.

[0043] In the description of this embodiment, the terms "first" and "second" are used only for descriptive purposes and have no special meaning.

[0044] Figure 1 This is a schematic diagram of the structure of a battery pack simulator provided in an embodiment of the present invention, as shown below. Figure 1 As shown, the battery pack simulator 200 includes: a power supply module 10 for outputting a first voltage signal; a voltage conversion module 20 electrically connected to the power supply module 10 for receiving the first voltage signal and converting it into a second voltage signal; the voltage value of the second voltage signal is less than the voltage value of the first voltage signal; the voltage conversion module 20 includes a step-down unit 201 and a control unit 202; the step-down unit 201 includes a first gallium nitride metal oxide semiconductor field-effect transistor 2011 and a second gallium nitride metal oxide semiconductor field-effect transistor 2012; the control terminals of the first gallium nitride metal oxide semiconductor field-effect transistor 2011 and the second gallium nitride metal oxide semiconductor field-effect transistor 2012 are both electrically connected to the first control terminal of the control unit 202, and the input terminal of the first gallium nitride metal oxide semiconductor field-effect transistor 2011 is electrically connected to the second gallium nitride metal oxide semiconductor field-effect transistor 2012. The output terminal of the field-effect transistor 2012 is electrically connected; multiple parallel-connected analog cells 30 are all electrically connected to the step-down unit 201 to receive the second voltage signal and convert the second voltage signal into an output voltage signal; the voltage value of the output voltage signal is less than the voltage value of the second voltage signal; each analog cell 30 includes a resonant unit 301; the resonant unit 301 includes a third gallium nitride metal oxide semiconductor field-effect transistor 3011 and a fourth gallium nitride metal oxide semiconductor field-effect transistor 3012; the control terminals of the third gallium nitride metal oxide semiconductor field-effect transistor 3011 and the fourth gallium nitride metal oxide semiconductor field-effect transistor 3012 are both electrically connected to the second control terminal of the control unit 202, and the input terminal of the third gallium nitride metal oxide semiconductor field-effect transistor 3011 is electrically connected to the output terminal of the fourth gallium nitride metal oxide semiconductor field-effect transistor 3012.

[0045] Specifically, the power supply module 10 is electrically connected to the voltage conversion module 20 and outputs a first voltage signal to the voltage conversion module 20 to power the voltage conversion module 20, thereby ensuring the normal operation of the battery pack simulator 200. For example, the voltage value of the first voltage signal can be 24V.

[0046] Specifically, the voltage conversion module 20 includes a step-down unit 201 and a control unit 202, with the control unit 202 electrically connected to the step-down unit 201. The step-down unit 201 receives a first voltage signal and converts it into a second voltage signal. The voltage value of the second voltage signal is lower than that of the first voltage signal, thus enabling further voltage reduction through the step-down unit 201.

[0047] Specifically, multiple parallel-connected analog cells 30 are electrically connected to the step-down unit 201 to receive the second voltage signal and convert it into an output voltage signal. The voltage value of the output voltage signal is less than that of the second voltage signal. In other words, the analog cells 30 are used to step down the received second voltage signal so that the voltage value of the output voltage signal meets the 2V-4V requirement.

[0048] Specifically, Figure 2 This is a schematic diagram of the electrical connection between a first voltage conversion module and a simulated battery cell provided in an embodiment of the present invention, as shown below. Figure 2 As shown, the buck converter 201 includes a first gallium nitride (GaN) metal-oxide-semiconductor (MOSFET) field-effect transistor (GNT-SFET) 2011 and a second GaN MOSFET 2012. The control terminals of both the first GNT-SFET 2011 and the second GNT-SFET 2012 are electrically connected to the first control terminal of the control unit 202, thus enabling the control unit 202 to control the on / off state of the two transistors. The input terminal of the first GNT-SFET 2011 is electrically connected to the output terminal of the second GNT-SFET 2012. In other words, the buck converter 201 includes a half-bridge structure formed by the first GNT-SFET 2011 and the second GNT-SFET 2012. The buck converter 201 can be a Buck transformer, but unlike existing Buck transformers, it uses a half-bridge GaN-SFET formed by two transistors instead of the transistors and freewheeling diodes in existing Buck transformers. Because gallium nitride metal-oxide-semiconductor field-effect transistors have ultra-low on-resistance, ultra-low drive requirements, and ultra-high switching frequency, they can greatly improve the efficiency of the entire topology (>98%), and at a lower cost.

[0049] Specifically, the resonant unit 301 includes a third gallium nitride metal-oxide-semiconductor field-effect transistor (GaNMT) 3011 and a fourth GaNMT 3012. The control terminals of both the third GaNMT 3011 and the fourth GaNMT 3012 are electrically connected to the second control terminal of the control unit 202, allowing the control unit 202 to control the on / off state of the two transistors. The input terminal of the third GaNMT 3011 is electrically connected to the output terminal of the fourth GaNMT 3012. The difference from existing resonant units lies in the use of a half-bridge GaNMT formed by two transistors instead of the full-bridge transistors in existing resonant units. This results in a smaller number of components and a simpler, more compact structure in the resonant unit 301 provided by this embodiment. Furthermore, because GaNMTs have ultra-low on-resistance, ultra-low drive requirements, and ultra-high switching frequencies, the efficiency of the entire topology can be significantly improved (>98%), while also being relatively low in cost. Therefore, the battery pack simulator 200 has a simple, compact structure and high efficiency.

[0050] For example, the control unit 202 may be a microcontroller unit (MCU).

[0051] The battery pack simulator provided in this embodiment of the invention includes a voltage conversion module comprising a buck unit and a control unit. The buck unit includes a first gallium nitride (GaN) metal-oxide-semiconductor (MOSFET) and a second GaN MOSFET, i.e., a half-bridge GaN MOSFET is used as part of the buck unit, thus simplifying the buck unit structure. Furthermore, each simulated cell includes a resonant unit; the resonant unit includes a third GaN MOSFET and a fourth GaN MOSFET, i.e., a half-bridge GaN MOSFET is used as part of the resonant unit, thus simplifying the resonant unit structure. This, in turn, simplifies the structure of the battery pack simulator, reduces the number of components used, and increases operating efficiency.

[0052] Optional, Figure 3 This is a schematic diagram of the electrical connection between the second voltage conversion module and the analog battery cell provided in an embodiment of the present invention, as shown below. Figure 3 As shown, the first gallium nitride metal oxide semiconductor field-effect transistor 2011 and the second gallium nitride metal oxide semiconductor field-effect transistor 2012 are integrated on the first chip 40; the third gallium nitride metal oxide semiconductor field-effect transistor 3011 and the fourth gallium nitride metal oxide semiconductor field-effect transistor 3012 are integrated on the second chip 50.

[0053] Specifically, the first gallium nitride metal oxide semiconductor field-effect transistor 2011 and the second gallium nitride metal oxide semiconductor field-effect transistor 2012 are integrated on the first chip 40. This ensures that the process parameters of the two transistors are consistent and enables the miniaturization of the voltage conversion module 20.

[0054] Specifically, the third gallium nitride metal oxide semiconductor field-effect transistor 3011 and the fourth gallium nitride metal oxide semiconductor field-effect transistor 3012 are integrated on the second chip 50. This ensures that the process parameters of the two transistors are consistent and enables the miniaturization of the resonant unit 301, thereby enabling the miniaturization of the battery pack simulator and helping to ensure the stability and reliability of the battery pack simulator.

[0055] Optional, continue to refer to Figure 2 The voltage conversion module 20 further includes a voltage divider unit 203; the voltage divider unit 203 includes a first resistor R1 and a second resistor R2; the voltage conversion module 20 also includes a first inductor L1; the first end of the first inductor L1 is electrically connected to the input end of the first gallium nitride metal oxide semiconductor field-effect transistor 2011 and the output end of the second gallium nitride metal oxide semiconductor field-effect transistor 2012; the second end of the first inductor L1 is electrically connected to the first end of the first resistor R1; the second end of the first resistor R1 and the first end of the second resistor R2 are both electrically connected to the sampling end of the control unit 202; the second end of the second resistor R2 is electrically connected to the sampling end and the ground end of the control unit 202; the output end of the first gallium nitride metal oxide semiconductor field-effect transistor 2011 is electrically connected to the positive terminal of the power supply module 10; the input end of the second gallium nitride metal oxide semiconductor field-effect transistor 2012 is electrically connected to the negative terminal and the ground end of the power supply module 10.

[0056] Specifically, when the first gallium nitride metal-oxide-semiconductor field-effect transistor 2011 is turned on, the second gallium nitride metal-oxide-semiconductor field-effect transistor 2012 is turned off. At this time, current flows through the first inductor L1 to the output terminal. As the current in the first inductor L1 increases linearly, self-inductance occurs, which impedes the current increase. The first inductor L1 can convert electrical energy into magnetic energy for storage; at this time, the potential direction of the inductor is positive on the left and negative on the right.

[0057] When the first gallium nitride metal-oxide-semiconductor field-effect transistor 2011 is turned off, no current flows to the first inductor L1. However, the current in the first inductor L1 does not suddenly drop to zero, but gradually decreases. Since the first inductor L1 impedes the current change, a self-induced electromotive force (EMF) with negative on the left and positive on the right is generated, causing the second gallium nitride metal-oxide-semiconductor field-effect transistor 2012 to turn on. As the current in the first inductor L1 decreases, the magnetic energy stored in the first inductor L1 is converted into electrical energy and released to the output terminal.

[0058] Specifically, during the conduction of the first gallium nitride metal-oxide-semiconductor field-effect transistor 2011, the voltage U of the first inductor L1 is... L1 For U L1 =Ui-U0; where Ui is the output voltage of power supply module 10 and U0 is the output voltage of buck unit 201. When the second gallium nitride metal oxide semiconductor field-effect transistor 2012 is turned on, the voltage U of the first inductor L1 is... L1 For U L1 =-U0. Since the buck unit 201 is a stable circuit, it maintains a stable transistor switching. The current flowing into the first inductor L1 during transistor conduction is equal to the current flowing into the first inductor L1 during transistor turn-off. Thus, the output voltage of the buck unit 201 is equal to the input voltage multiplied by the duty cycle, i.e., U0 = Ui × d. Here, the duty cycle d is the ratio of the transistor's on-time to its period, thereby achieving the buck function. Furthermore, the output voltage of the buck unit 201 can be adjusted by changing the duty cycle of the drive signal.

[0059] Specifically, the voltage divider unit 203 includes a first resistor R1 and a second resistor R2. The second end of the first resistor R1 and the first end of the second resistor R2 are both electrically connected to the sampling terminal of the control unit 202. The second end of the second resistor R2 is electrically connected to both the sampling terminal and the ground terminal of the control unit 202. By setting the voltage divider unit 203 to simulate the voltage value output by the downstream analog battery cell, since the downstream analog battery cell is isolated and cannot be grounded, the voltage divider unit 203 can simulate the voltage value output by the downstream analog battery cell in the upstream stage. For example, the host computer can be electrically connected to the input terminal of the control unit 202 through an isolation chip. In this case, a preset voltage value of 3.3V can be input through the host computer, and the control unit 202 will output a pulse width modulation signal to control the buck unit 201 to output a first voltage signal. The first voltage signal passes through the resonant circuit. Since the gain of the resonant circuit is 1, the first voltage signal remains unchanged. However, after the transformer turns ratio is changed, the voltage value is reduced to 1 / n of the original value. At the same time, 1 / n of the output value of the step-down unit 201 will also be fed back to the control unit 202. The control unit 202 will adjust the duty cycle of the current pulse width modulation signal according to the current feedback value until the feedback value is consistent with the value of 3.3V set by the host computer.

[0060] For example, the buck converter 201 may further include a first filter capacitor C11 and a second filter capacitor C12. One end of the first filter capacitor is electrically connected to the positive terminal of the power supply module 10, and the other end is electrically connected to the negative terminal of the power supply module 10. One end of the second filter capacitor C12 is electrically connected to the second terminal of the first inductor L1, and the other end is electrically connected to the input terminal of the fourth gallium nitride metal oxide semiconductor field-effect transistor 3012. The two ends of the second filter capacitor C12 can serve as the output terminals of the buck converter 201.

[0061] It should be noted that the device selection and design of the step-down unit 201 need to support a sufficiently large output power to withstand the power of subsequent multiplexing. This embodiment of the invention does not impose a specific limitation on the number of analog cells 30.

[0062] Optional, continue to refer to Figure 2 The resonant unit also includes a second inductor L2, a transformer T, a first capacitor C1, a first diode D1, a second diode D2, a second capacitor C2, and a third inductor L3; the output terminal of the third gallium nitride metal-oxide-semiconductor field-effect transistor 3011 is electrically connected to the second terminal of the first inductor L1; the input terminal of the third gallium nitride metal-oxide-semiconductor field-effect transistor 3011 is electrically connected to the output terminal of the fourth gallium nitride metal-oxide-semiconductor field-effect transistor 3012 and the first terminal of the second inductor L2; the second terminal of the second inductor L2 is electrically connected to the first terminal of the primary winding side of the transformer T, and the primary winding of the transformer T... The second end of the winding side is electrically connected to the negative terminal of the power supply module 10 and the input terminal of the fourth gallium nitride metal oxide semiconductor field-effect transistor 3012 through the first capacitor C1; the first end of the secondary winding side of the transformer T is electrically connected to the positive terminal of the first diode D1, and the second end of the secondary winding side of the transformer T is electrically connected to the positive terminal of the second diode D2; the negative terminals of the first diode D1 and the second diode D2 are both electrically connected to the first end of the second capacitor C2; the middle end of the secondary winding side of the transformer T is electrically connected to the first end of the third inductor L3, and the second end of the third inductor L3 is electrically connected to the second end of the second capacitor C2.

[0063] Specifically, the third gallium nitride metal oxide semiconductor field-effect transistor 3011 and the fourth gallium nitride metal oxide semiconductor field-effect transistor 3012 are used to replace the full-bridge module of the resonant unit in the prior art. That is, a half-bridge structure formed by two transistors is used instead of a full-bridge structure. This can reduce the number of devices and simplify the circuit structure, and save costs.

[0064] Specifically, the resonant unit 301 adopts a fixed-gain open-loop design with a gain of 1. This means that the switching frequency and duty cycle of the resonant unit 301 are maintained at the resonant frequency of the LC circuit. This significantly reduces the difficulty of controlling the switching of the resonant unit 301. Furthermore, the pulse width signal output from the control unit 202 to the resonant unit 301 requires no adjustment; it simply outputs a square wave with a fixed frequency and duty cycle. The resonant characteristic of the resonant unit 301 is that at the LC frequency resonant point, the topology gain remains constant at 1 regardless of input voltage adjustments. If the gain needs to be reduced, the multiplier can be controlled by the turns ratio of the subsequent transformer coil. Moreover, since the gain of the resonant unit 301 is 1, the voltage value before transformer T is the same as the voltage output of the step-down unit 201. However, after the turns ratio change of transformer T, the voltage value is reduced to 1 / n of the original value, thus further stepping down the voltage signal output by the step-down unit 201 to achieve the output of a simulated battery cell.

[0065] Specifically, the first diode D1 and the second diode D2 form a bridge rectifier circuit, and the third inductor L3 and the second capacitor C2 form a filter circuit to improve the working efficiency of the resonant unit 301 and the output ripple.

[0066] It should be noted that the negative terminals of the first diode D1 and the second diode D2 are both electrically connected to the first terminal of the second capacitor C2. The first terminal of the second capacitor C2 is also electrically connected to the second terminal of the third inductor in the next stage resonant unit 301 and the second terminal of the second capacitor.

[0067] Optional, continue to refer to Figure 2 The turns ratio of the primary winding to the secondary winding is n:1; the resistance of the first resistor is R1, and the resistance of the second resistor is R2; where R1 / (R1+R2) = 1 / n.

[0068] Specifically, to ensure that the feedback voltage is consistent with the output voltage of the analog battery cell, the turns ratio of the primary winding to the secondary winding is n:1, and R1 / (R1+R2) = 1 / n, meaning that the voltage after passing through the secondary winding of the transformer is 1 / n of the voltage before passing through the secondary winding. The step-down unit 201 outputs the first voltage signal to the resonant unit 301. Since the gain of the resonant circuit is 1, the voltage value before passing through the secondary winding of the transformer is equal to the voltage value of the first voltage signal. However, after the transformer turns ratio is changed, the voltage value is reduced to 1 / n of the original value. At the same time, 1 / n of the output value of the step-down unit 201 is also fed back to the control unit 202. The control unit 202 will adjust the duty cycle of the current pulse width modulation signal according to the current feedback value until the feedback value is consistent with the value set by the host computer.

[0069] For example, when the turns ratio of the primary winding to the secondary winding is 3:1, R1 / (R1+R2) = 1 / 3.

[0070] Optional, Figure 4This is an electrical schematic diagram of a mode switching module and a control unit provided in an embodiment of the present invention. (Continue referring to...) Figure 1 and Figure 4 The pool simulator 200 also includes: a mode switching module 60; the mode switching module 60 includes a third resistor R3, a sliding rheostat R, a first transistor Q, a fourth resistor R4, a third capacitor C3, a manual button S1, and a fifth resistor R5; the first end of the third resistor R3 is electrically connected to the power supply module 10, and the second end of the third resistor R3 is electrically connected to the sliding end of the sliding rheostat R and the sampling terminal ADC of the control unit 202; the fixed end of the sliding rheostat R is electrically connected to the input terminal of the first transistor Q, the control terminal of the first transistor Q is electrically connected to the first end of the fourth resistor R4, and the output terminal of the first transistor Q is electrically connected to the first end of the third capacitor C3 and the ground terminal; the second end of the third capacitor C3 and the second end of the fourth resistor R4 are electrically connected to the first end of the fifth resistor R5 and the reset terminal REST of the control unit 202 through the manual button S1, and the second end of the fifth resistor R5 is electrically connected to the power supply terminal of the control unit 202; the host computer 70 is electrically connected to the input terminal of the control unit 202.

[0071] Specifically, the host computer 70 can also be electrically connected to the input terminal of the control unit 202 via a CAN communication isolation chip. In this way, in the host computer control mode, the host computer 70 can input a preset voltage value to the control unit 202, so that the control unit 202 outputs a pulse width modulation signal to the step-down unit 201 for a first voltage reduction. The resonant unit 301 performs a second voltage reduction on the voltage signal output by the step-down unit 201 and isolates the output power network, thereby enabling the analog battery cell to finally output the preset voltage value.

[0072] Specifically, the mode switching module 60 is used to switch the host computer control mode to manual control mode via the reset terminal REST of the control unit 202. Taking a preset voltage value of 3.3V as an example, when the manual button S1 is pressed, due to the presence of the third capacitor C3, 3.3V is momentarily short-circuited and pulled down. The control unit 202 immediately resets and exits the host computer mode. After the third capacitor C3 is fully charged, the first transistor Q is turned on, entering the manual control mode. At the same time, the value collected by the sampling terminal ADC of the control unit 202 is converted into the preset output voltage value. At this time, the sampling terminal ADC will change from the original 5V to 5*R / (R+R3). Since the output voltage range of the analog cell is 2V-4V, 5*R / (R+R3)≤4V. By changing the resistance value of the sliding rheostat R, the output voltage of all analog cells can be changed. In this way, on the one hand, the voltage consistency of each analog cell can be ensured by manual adjustment, and on the other hand, there is no need to rely too much on the host computer to control the change of output voltage. The operation is convenient, simple, and highly versatile.

[0073] Understandably, the software logic of the mode switching module 60 is as follows: when entering the host computer, it uses the preset voltage value set by the host computer 70 as a reference; when exiting the host computer, it uses the voltage of the ADC at the sampling end of the control unit as a reference. If the manual button S1 is not closed while exiting the host computer, the control unit 202 will detect that the ADC voltage at the sampling end is greater than 4V and will stop sending the pulse width modulation signal. Conversely, if the manual button S1 is closed while entering the host computer, the control unit 202 will detect that the ADC voltage at the sampling end is less than 4V and will disable the host computer function by default. All analog cells will have no output voltage and will enter a sleep state. At this time, pressing the manual button S1 will immediately enter the manual control mode and open the host computer to enter the host computer control mode.

[0074] Optional, continue to refer to Figure 1 The battery pack simulator 200 also includes: a voltage sampling module 80 and an alarm module 90; the sampling terminal of the voltage sampling module 80 is electrically connected to the output terminal of each simulated cell 30, and is used to collect the current voltage value output by each simulated cell 30; the comparison terminal of the control unit 202 is electrically connected to the output terminal of the voltage sampling module 80, and the comparison terminal of the control unit 202 is also electrically connected to the output terminal of the power management module 100; the sampling terminal of the power management module 100 is electrically connected to the output terminal of each simulated cell 30, and is used to collect the target voltage value output by each simulated cell 30; the alarm signal output terminal of the control unit 202 is electrically connected to the alarm module 90; the control unit 202 is used to receive the current voltage value and target voltage value output by each simulated cell 30, and output an alarm signal to the alarm module 90 according to the current voltage value, target voltage value and preset voltage difference output by each simulated cell 30.

[0075] Specifically, the power management module 100 is located outside the battery pack simulator 200. The power management module 100 is electrically connected to the output terminal of each simulated cell 30 and is used to receive the target voltage value output by each simulated cell 30 and transmit each target voltage value to the comparison terminal of the control unit 202.

[0076] Specifically, the battery pack simulator 200 includes a voltage sampling module 80, which is electrically connected to the output terminal of each simulated cell 30. The voltage sampling module 80 is used to receive the current voltage value output by each simulated cell 30 and transmit each current voltage value to the comparison terminal of the control unit 202.

[0077] Specifically, the control unit 202 receives the target voltage value and the current voltage value output by each analog cell 30, and compares the multiple target voltage values ​​and multiple current voltage values ​​one by one. When the difference between the target voltage value and the current voltage value corresponding to any analog cell 30 does not meet the preset voltage difference, the control unit 202 outputs an alarm signal to the alarm module 90. In this way, the voltage sampling accuracy can be tested in real time, and the detection result can be known through the alarm module 90, without having to compare the output voltage of each analog cell individually.

[0078] For example, taking the number of simulated cells 30 as m, when the voltage difference between the target voltage value and the current voltage value of one of the m simulated cells 30 does not meet the preset voltage difference, the alarm module 90 will sound an alarm.

[0079] For example, the power management module 100 can be electrically connected to the output terminals of each simulated cell 30 via an output interface located on the battery pack simulator 200. The number of output interfaces is greater than or equal to the number of simulated cells 30.

[0080] Optional, Figure 5 This is a schematic diagram of the electrical principle of an alarm module and a control unit provided in an embodiment of the present invention. (Continue referring to...) Figure 1 and Figure 5 The alarm module 90 includes a sixth resistor R6 and an alarm indicator D; the first end of the sixth resistor R6 is electrically connected to the alarm signal output terminal of the control unit 202, the second end of the sixth resistor R6 is electrically connected to one end of the alarm indicator D, and the other end of the alarm indicator D is electrically connected to the ground terminal.

[0081] Specifically, when the difference between the target voltage value and the current voltage value corresponding to any simulated cell 30 does not meet the preset voltage difference, the control unit 202 outputs an alarm signal to the alarm indicator D. At this time, the alarm indicator D lights up to indicate that there is a problem with the voltage sampling accuracy, so that maintenance personnel can keep abreast of the output voltage status of the simulated cell.

[0082] Specifically, the sixth resistor R6 can serve as a current limiting protection, preventing the alarm indicator D from being burned out.

[0083] For example, the color of the alarm indicator D can be red. This embodiment of the invention does not specifically limit the color of the alarm indicator.

[0084] Optional, continue to refer to Figure 1 The battery pack simulator 200 also includes: an isolation chip 110; the output terminal of the voltage acquisition module 90 and the comparison terminal of the control unit 202 are electrically connected through the isolation chip 110.

[0085] Specifically, by setting an isolation chip 110 between the output terminal of the voltage acquisition module 90 and the comparison terminal of the control unit 202, electrical isolation can be achieved, thereby ensuring stable signal transmission between the output terminal of the voltage acquisition module 90 and the comparison terminal of the control unit 202.

[0086] For example, the isolation chip 110 may be an I2C communication isolation chip.

[0087] Optional, continue to refer to Figure 1 The power supply module 10 includes a regulated power supply 101, a first power conversion unit 102, and a second power conversion unit 103. The regulated power supply 101 is electrically connected to the input terminals of the first power conversion unit 102 and the second power conversion unit 103. The output terminal of the first power conversion unit 102 is electrically connected to the power supply terminal of the mode switching module 60, and the output terminal of the second power conversion unit 103 is electrically connected to the power supply terminal of the control unit 202.

[0088] Specifically, the regulated power supply 101 is used to provide a stable voltage signal. For example, the voltage output of the regulated power supply 101 can be 24V.

[0089] Specifically, the first power conversion unit 102 is used to convert the voltage output from the regulated power supply 101 into the voltage required by the mode switching module 60, thereby powering the mode switching module 60 and ensuring its normal operation. For example, the first power conversion unit 102 can convert 24V to 5V. For example, after the first power conversion unit 102 converts 24V to 5V, electrical isolation can also be achieved using DC-DC power isolation.

[0090] Specifically, the second power conversion unit 103 is used to convert the voltage output from the regulated power supply 101 into the voltage required by the control unit 202, thereby powering the control unit 202 and ensuring its normal operation. For example, the second power conversion unit 103 can convert 24V to 3.3V. For example, after the second power conversion unit 103 converts 24V to 3.3V, electrical isolation can also be achieved using DC-DC power isolation.

[0091] For example, the first power conversion unit 102 and the second power conversion unit 103 can both be low dropout linear regulators.

[0092] Obviously, the above embodiments of the present invention are merely examples for clearly illustrating the present invention, and are not intended to limit the implementation of the present invention. Those skilled in the art will be able to make various obvious changes, readjustments, and substitutions without departing from the scope of protection of the present invention. It is neither necessary nor possible to exhaustively describe all embodiments here. Any modifications, equivalent substitutions, and improvements made within the spirit and principles of the present invention should be included within the scope of protection of the claims of the present invention.

Claims

1. A battery pack simulator, characterized in that, include: The power supply module is used to output the first voltage signal; A voltage conversion module, electrically connected to the power supply module, is used to receive the first voltage signal and convert the first voltage signal into a second voltage signal; the voltage value of the second voltage signal is less than the voltage value of the first voltage signal; the voltage conversion module includes a step-down unit and a control unit; the step-down unit includes a first gallium nitride metal oxide semiconductor field-effect transistor and a second gallium nitride metal oxide semiconductor field-effect transistor; the control terminals of the first gallium nitride metal oxide semiconductor field-effect transistor and the second gallium nitride metal oxide semiconductor field-effect transistor are both electrically connected to the first control terminal of the control unit, and the input terminal of the first gallium nitride metal oxide semiconductor field-effect transistor is electrically connected to the output terminal of the second gallium nitride metal oxide semiconductor field-effect transistor; Multiple analog battery cells connected in parallel are electrically connected to the step-down unit to receive the second voltage signal and convert it into an output voltage signal; the voltage value of the output voltage signal is less than the voltage value of the second voltage signal. Each of the simulated battery cells includes a resonant unit; the resonant unit includes a third gallium nitride metal oxide semiconductor field-effect transistor and a fourth gallium nitride metal oxide semiconductor field-effect transistor; the control terminals of the third gallium nitride metal oxide semiconductor field-effect transistor and the fourth gallium nitride metal oxide semiconductor field-effect transistor are both electrically connected to the second control terminal of the control unit, and the input terminal of the third gallium nitride metal oxide semiconductor field-effect transistor is electrically connected to the output terminal of the fourth gallium nitride metal oxide semiconductor field-effect transistor.

2. The battery pack simulator according to claim 1, characterized in that, The first gallium nitride metal oxide semiconductor field-effect transistor and the second gallium nitride metal oxide semiconductor field-effect transistor are integrated on the first chip; The third gallium nitride metal oxide semiconductor field-effect transistor and the fourth gallium nitride metal oxide semiconductor field-effect transistor are integrated on the second chip.

3. The battery pack simulator according to claim 1, characterized in that, The voltage conversion module further includes a voltage divider unit; the voltage divider unit includes a first resistor and a second resistor; The voltage conversion module also includes a first inductor; The first end of the first inductor is electrically connected to the input terminal of the first gallium nitride metal oxide semiconductor field-effect transistor and the output terminal of the second gallium nitride metal oxide semiconductor field-effect transistor; the second end of the first inductor is electrically connected to the first end of the first resistor, the second end of the first resistor and the first end of the second resistor are both electrically connected to the sampling terminal of the control unit, and the second end of the second resistor is electrically connected to the sampling terminal and the ground terminal of the control unit. The output terminal of the first gallium nitride metal oxide semiconductor field-effect transistor is electrically connected to the positive terminal of the power supply module, and the input terminal of the second gallium nitride metal oxide semiconductor field-effect transistor is electrically connected to the negative terminal and the ground terminal of the power supply module.

4. The battery pack simulator according to claim 3, characterized in that, The resonant unit also includes a second inductor, a transformer, a first capacitor, a first diode, a second diode, a second capacitor, and a third inductor; The output terminal of the third gallium nitride metal oxide semiconductor field-effect transistor is electrically connected to the second terminal of the first inductor; the input terminal of the third gallium nitride metal oxide semiconductor field-effect transistor is electrically connected to the output terminal of the fourth gallium nitride metal oxide semiconductor field-effect transistor and the first terminal of the second inductor; the second terminal of the second inductor is electrically connected to the first terminal of the primary winding side of the transformer, and the second terminal of the primary winding side of the transformer is electrically connected to the negative terminal of the power supply module and the input terminal of the fourth gallium nitride metal oxide semiconductor field-effect transistor through the first capacitor; The first end of the secondary winding side of the transformer is electrically connected to the positive terminal of the first diode, and the second end of the secondary winding side of the transformer is electrically connected to the positive terminal of the second diode; the negative terminals of both the first and second diodes are electrically connected to the first end of the second capacitor; the middle end of the secondary winding side of the transformer is electrically connected to the first end of the third inductor, and the second end of the third inductor is electrically connected to the second end of the second capacitor.

5. The battery pack simulator according to claim 4, characterized in that, The turns ratio of the primary winding to the secondary winding is n:1; The resistance of the first resistor is R1, and the resistance of the second resistor is R2; where R1 / (R1+R2) = 1 / n.

6. The battery pack simulator according to claim 1, characterized in that, The battery pack simulator also includes: a mode switching module; The mode switching module includes a third resistor, a sliding rheostat, a first transistor, a fourth resistor, a third capacitor, a manual button, and a fifth resistor; The first end of the third resistor is electrically connected to the power supply module, and the second end of the third resistor is electrically connected to the sliding end of the variable resistor and the sampling end of the control unit; the fixed end of the variable resistor is electrically connected to the input end of the first transistor, the control end of the first transistor is electrically connected to the first end of the fourth resistor, and the output end of the first transistor is electrically connected to the first end of the third capacitor and the ground end; the second end of the third capacitor and the second end of the fourth resistor are electrically connected to the first end of the fifth resistor and the reset end of the control unit through the manual button, and the second end of the fifth resistor is electrically connected to the power supply end of the control unit; The host computer is electrically connected to the input terminal of the control unit.

7. The battery pack simulator according to claim 1, characterized in that, The battery pack simulator also includes: a voltage sampling module and an alarm module; The sampling terminal of the voltage sampling module is electrically connected to the output terminal of each of the simulated cells in a one-to-one correspondence, and is used to collect the current voltage value output by each of the simulated cells. The comparison terminal of the control unit is electrically connected to the output terminal of the voltage sampling module, and the comparison terminal of the control unit is also electrically connected to the output terminal of the power management module; the sampling terminal of the power management module is electrically connected to the output terminal of each of the analog cells one by one, for collecting the target voltage value output by each of the analog cells; the alarm signal output terminal of the control unit is electrically connected to the alarm module. The control unit is used to receive the current voltage value and the target voltage value output by each of the simulated cells, and output an alarm signal to the alarm module according to the current voltage value, the target voltage value and the preset voltage difference output by each of the simulated cells.

8. The battery pack simulator according to claim 7, characterized in that, The alarm module includes a sixth resistor and an alarm indicator light; The first end of the sixth resistor is electrically connected to the alarm signal output terminal of the control unit, the second end of the sixth resistor is electrically connected to one end of the alarm indicator light, and the other end of the alarm indicator light is electrically connected to the ground terminal.

9. The battery pack simulator according to claim 7, characterized in that, The battery pack simulator also includes: an isolation chip; The output terminal of the voltage acquisition module is electrically connected to the comparison terminal of the control unit through the isolation chip.

10. The battery pack simulator according to claim 6, characterized in that, The power supply module includes a regulated power supply, a first power conversion unit, and a second power conversion unit. The regulated power supply is electrically connected to the input terminal of the first power conversion unit and the input terminal of the second power conversion module; The output terminal of the first power conversion module is electrically connected to the power terminal of the mode switching module, and the output terminal of the second power conversion module is electrically connected to the power terminal of the control unit.

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