Low-power-consumption battery simulator based on DCDC

Abstract

The invention discloses a DCDC-based low-power-consumption battery simulator, and relates to the technical field of power battery sampling testing, and the DCDC-based low-power-consumption battery simulator comprises a single battery simulator M0 which inputs 12Vdc of a 12V power supply M4, converts the 12Vdc into 5Vdc through an isolation power supply module, converts the 5Vdc into 3.3 Vdc through a DCDC power supply chip, controls ripple waves within a reasonable range, and outputs the ripple waves to a simulator output connector M1; in the supporting plate component, a single battery simulator M0 is connected with a cell simulator plug-in group M3; the quick connection terminal group M2 receives the 3.3 V direct current voltage output by the M3; the power supply and power supply protection part M4 provides 12V voltage for the M0, and the simulation temperature part M5 simulates the temperature of a battery cell and is connected with a simulator output connector M1; the M1 receives the 3.3 V DC voltage output by the M3 and the cell temperature output by the simulation temperature part M5. The invention provides a low-power-consumption battery simulator for better carrying out BMS (Battery Management System) test.

Description

Technical Field

[0001] The present invention relates to the technical field of power battery sampling and testing, and more specifically, to a low-power battery simulator based on DCDC. Background Art

[0002] In new energy vehicles, energy storage, and low-voltage battery applications, the BMS not only has diverse functions but also controls the usage process of the battery pack. The quality of its performance will directly affect the usage safety, efficiency, cycle life of the battery pack, as well as the personal safety of users. Common testing processes are as follows Figure 1 .

[0003] Precisely because the BMS shoulders such a great responsibility, during most cycles of BMS design and assembly, such as development stage, reliability verification stage, incoming material stage, software and hardware testing stage, etc., it is necessary to conduct certain tests on the BMS to strictly control the quality of software and hardware.

[0004] However, using a real battery pack to provide a single-cell power supply solution has battery factors such as long battery charging and discharging time, low accuracy of single-cell voltage, large voltage difference between single cells, unstable single-cell temperature, high test power consumption, and unstable various parameters, resulting in great difficulty and long test cycle for BMS testing, restricting BMS testing, and making it difficult to control the quality of software and hardware. If software problems are not quickly identified before production, it is very likely to cause misjudgment in the battery management system and trigger safety problems, such as overcharging and over-discharging. Therefore, the research and use of battery simulators or test platforms centered on battery simulators make software and hardware testing more convenient and efficient, make data accuracy higher, make test work safer and more economical, and are also very necessary for BMS research and design.

[0005] Therefore, how to provide a low-power battery simulator for BMS testing is an urgent problem to be solved by those skilled in the art. Summary of the Invention

[0006] In view of this, the present invention provides a low-power battery simulator based on DCDC to solve the problems existing in the above background art.

[0007] To achieve the above object, the present invention adopts the following technical solutions:

[0008] A low-power battery simulator based on DCDC, comprising: a single-cell battery simulator M0 and a support plate component. The single-cell battery simulator M0 includes a filter capacitor C5, a filter capacitor C4, a filter capacitor C2, an isolated power supply module U3, a DCDC power chip U2, an LC filter circuit, and an M0 output connector. The filter capacitor C5 receives a 12V DC voltage, filters the 12V DC voltage, and then transmits it to the isolated power supply module U3. The isolated power supply module U3 converts the filtered DC voltage from 12V to 5V and isolates the electrical signal. The output end of the isolated power supply module U3 is connected to the filter capacitors C4 and C2. The filter capacitors C4 and C2 perform secondary filtering on the 5V DC voltage and then transmit it to the DCDC power chip U2. The DCDC power chip U2 converts the 5V DC voltage into a 3.3V DC voltage, and transmits the 3.3V DC voltage to the M0 output connector through the LC filter circuit. The support plate component includes a simulator output connector M1, a quick-connect terminal group M2, a cell simulator plug-in group M3, a 12V power supply and power protection part M4, and a T1-T14 analog temperature part M5, all of which are arranged on the support plate component. The M0 output connector is connected to the cell simulator plug-in group M3. The quick-connect terminal group M2 receives the 3.3V DC voltage output by the cell simulator plug-in group M3. The 12V power supply and power protection part M4 provides a 12V voltage for the single-cell battery simulator M0. The T1-T14 analog temperature part M5 is used to simulate the cell temperature and is connected to the simulator output connector M1. The simulator output connector M1 receives the 3.3V DC voltage output by the cell simulator plug-in group M3 and the analog cell temperature output by the T1-T14 analog temperature part M5.

[0009] Preferably, the LC filter circuit and the M0 output connector further include: a ripple filtering capacitor and a light-emitting diode. The ripple filtering capacitor is connected to the output end of the inductor L1 in the LC filtering link to suppress 1.5MHz high-frequency EMI and reduce the output ripple. The light-emitting diode is connected in series at the output end of the ripple filtering capacitor, with a minimum lighting voltage of 2.3V, and is used to indicate whether the circuit voltage is normal. The negative electrode of the light-emitting diode is connected to the M0 output connector.

[0010] Preferably, the model of the M0 output connector is FH00843.

[0011] Preferably, there are 24 single-cell battery simulators M0, which are connected to the cell simulator plug-in group M3 through the M0 output connector, arranged in three rows, with B1-B8, B9-B16, and B17-B24 from left to right in each row.

[0012] Preferably, the isolated power supply module U3 includes: a first bipolar push-pull converter, a first isolation transformer, and a first rectifier and filter circuit. The first bipolar push-pull converter converts the 12V DC voltage into a high-frequency AC voltage. The first isolation transformer receives the high-frequency AC voltage output by the first bipolar push-pull converter and converts the voltage on the primary side to the secondary side through the principle of electromagnetic induction. The first rectifier and filter circuit converts the voltage output by the first isolation transformer into a 5V DC voltage.

[0013] Preferably, the DCDC power supply chip U2 includes: a second bipolar push-pull converter, a second isolation transformer, a second rectifier and filter circuit, a sampling circuit, a comparison circuit, a pulse width modulation circuit, an oscillator, an adjustable reference voltage circuit, and a feedback circuit. The second bipolar push-pull converter, the second isolation transformer, the second rectifier and filter circuit, the sampling circuit, and the comparison circuit are connected in sequence. The oscillator provides a clock signal for the pulse width modulation circuit. The adjustable reference voltage circuit provides a reference voltage for the pulse width modulation circuit. The second rectifier and filter circuit feeds back the output voltage to the adjustable reference voltage circuit through the feedback circuit.

[0014] Through the above technical solutions, compared with the prior art, the present invention discloses a low-power battery simulator based on DCDC. By using the DCDC solution to replace the LDO solution and device selection, the efficiency of converting 5V to 3.3V is increased from 66% to within 90%. Provide 12V power supply protection, use an ideal diode to replace the reverse connection protection diode, reduce the voltage drop of 0.27V of the diode. If the simulator current is 3A, the power loss due to heat is reduced by about 0.81W. The components generate less heat and have a longer service life. The output ripple is low. By using electrolytic capacitors and parallel tantalum capacitors, the 1.5MHz high-frequency PWM component of DCDC operation is solved, and components with lower output impedance ESR and ESL are used to reduce the conduction of ripple output and solve the problem of large DC / DC output ripple. The battery voltage simulation accuracy is high and can meet the usage conditions. Under the condition of a relatively large output current of the DCDC power supply chip, combined with its isolated power supply module and electrolytic capacitors, the output current can reach the expected value. The design of the battery simulator support board improves the scalability and maintainability of battery simulation. The support board of the battery simulator is also designed with reverse connection protection, TVS electrostatic and surge protection, and an ideal diode is also used to reduce the voltage drop loss of the reverse connection protection diode. Description of the Drawings

[0015] In order to more clearly illustrate the technical solutions in the embodiments of the present invention or the prior art, the following will briefly introduce the drawings required for the description of the embodiments or the prior art. Obviously, the drawings in the following description are only the embodiments of the present invention. For those of ordinary skill in the art, other drawings can be obtained according to the provided drawings without creative efforts.

[0016] Figure 1 System block diagram provided by the present invention;

[0017] Figure 2 Step flowchart provided by the present invention;

[0018] Figure 3 Cell simulator diagram provided by the present invention;

[0019] Figure 4 Composition diagram of DCDC output ripple provided by the present invention;

[0020] Figure 5 Design diagram of reverse connection prevention and TVS protection for 12V power supply provided by the present invention;

[0021] Figure 6 2D diagram of the battery simulator tooling platform provided by the present invention. Detailed implementation manners

[0022] Next, the technical solutions in the embodiments of the present invention will be clearly and completely described in conjunction with the accompanying drawings in the embodiments of the present invention. Obviously, the described embodiments are only a part of the embodiments of the present invention, rather than all the embodiments. All other embodiments obtained by those of ordinary skill in the art based on the embodiments of the present invention without creative efforts shall fall within the protection scope of the present invention.

[0023] An embodiment of the present invention discloses a low-power battery simulator based on DCDC, including: a single-cell battery simulator M0 and a support plate component. The single-cell battery simulator M0 includes a filter capacitor C5, a filter capacitor C4, a filter capacitor C2, an isolated power supply module U3, a DCDC power chip U2, an LC filter circuit, and an M0 output connector. The filter capacitor C5 receives a 12V DC voltage, filters the 12V DC voltage and then transmits it to the isolated power supply module U3; the isolated power supply module U3 converts the filtered DC voltage from 12V to 5V and isolates the electrical signal, and the output end of the isolated power supply module U3 is connected to the filter capacitors C4 and C2; the filter capacitors C4 and C2 perform secondary filtering on the 5V DC voltage and then transmit it to the DCDC power chip U2; the DCDC power chip U2 converts the 5V DC voltage into a 3.3V DC voltage, and transmits the 3.3V DC voltage to the M0 output connector through the LC filter circuit; the support plate component includes a simulator output connector M1, a quick-connection terminal group M2, a cell simulator plug-in group M3, a 12V power supply and power protection part M4, and a T1-T14 analog temperature part M5, all of which are arranged on the support plate component; the M0 output connector is connected to the cell simulator plug-in group M3; the quick-connection terminal group M2 receives the 3.3V DC voltage output by the cell simulator plug-in group M3; the 12V power supply and power protection part M4 provides a 12V voltage for the single-cell battery simulator M0, and the T1-T14 analog temperature part M5 is used to simulate the cell temperature and is connected to the simulator output connector M1; the simulator output connector M1 receives the 3.3V DC voltage output by the cell simulator plug-in group M3 and the analog cell temperature output by the T1-T14 analog temperature part M5.

[0024] In a specific embodiment, the LC filter circuit includes: The LC filter circuit is located between the output end of the DCDC power chip U2 and the ripple filter circuit, playing a connecting role. Its connection relationship is as follows:

[0025] Input connection: The voltage output from the pin LX of the DCDC power chip U2 is connected to one end of the inductor L1 in the LC filter circuit as the input of the LC filter circuit. Previously, the 12V DC voltage is converted to 5V through the filter capacitor C5 and the isolated power supply module U3, and then input to the DCDC power chip U2 after secondary filtering by the filter capacitors C4 and C2. After being converted to 3.3V by U2, it is output from the LX pin to the LC filter circuit.

[0026] Internal component connection: The other end of the inductor L1 is connected to one ends of the resistors R1 and R2. The other end of R1 is connected to the feedback pin FB of the DCDC power chip U2, and the other end of R2 is grounded (BGND). This connection method forms a feedback circuit for feeding back the output voltage signal to the inside of the chip to adjust the output voltage to be stable at 3.3V.

[0027] Output connection: The voltage output by the LC filter circuit is transmitted to the ripple filter circuit. That is, the inductor L1 is connected to components such as the capacitor C6 in the ripple filter circuit, providing a preliminarily filtered voltage for the ripple filter circuit to further suppress high-frequency ripples and make the final output voltage more stable and smooth. The ripple filter circuit includes ripple filtering capacitors (C6 - aluminum electrolytic capacitor, C7 - tantalum capacitor, C8 - tantalum capacitor, C9 - tantalum capacitor, C10 - tantalum capacitor, C11 - tantalum capacitor) and light-emitting diodes.

[0028] In a specific embodiment, as Figure 3 shown, the LC filter circuit and the M0 output connector further include: ripple filtering capacitors and light-emitting diodes. The ripple filtering capacitors are connected to the output end of the inductor L1 in the LC filtering section to suppress 1.5 MHz high-frequency EMI and reduce the output ripple. The light-emitting diodes are connected in series at the output end of the ripple filtering capacitors, with a minimum lighting voltage of 2.3V, used to indicate whether the circuit voltage is normal. The negative pole of the light-emitting diode is connected to the M0 output connector.

[0029] In a specific embodiment, the model of the M0 output connector is FH00843.

[0030] In a specific embodiment, there are 24 single-cell simulators M0, which are connected to the cell simulator plug-in group M3 through the M0 output connector. There are three rows, and from left to right in each row are B1 - B8, B9 - B16, and B17 - B24 respectively.

[0031] In a specific embodiment, the isolated power supply module U3 includes: a first bipolar push-pull converter, a first isolation transformer, and a first rectifier filter circuit. The first bipolar push-pull converter converts the 12V DC voltage into a high-frequency AC voltage. The first isolation transformer receives the high-frequency AC voltage output by the first bipolar push-pull converter and converts the voltage on the primary side to the secondary side through the principle of electromagnetic induction. The first rectifier filter circuit converts the voltage output by the first isolation transformer into a 5V DC voltage.

[0032] In a specific embodiment, the DCDC power chip U2 includes: a second bipolar push-pull converter, a second isolation transformer, a second rectifier filter circuit, a sampling circuit, a comparison circuit, a pulse width modulation circuit, an oscillator, an adjustable reference voltage circuit, and a feedback circuit. The second bipolar push-pull converter, the second isolation transformer, the second rectifier filter circuit, the sampling circuit, and the comparison circuit are connected in sequence. The oscillator provides a clock signal for the pulse width modulation circuit. The adjustable reference voltage circuit provides a reference voltage for the pulse width modulation circuit. The second rectifier filter circuit feeds back the output voltage to the adjustable reference voltage circuit through the feedback circuit.

[0033] Adopt the solution of isolation power module U3 + DC / DC power chip U2. This solution is a module designed based on the transformation principle, which can convert one voltage into another voltage, and at the same time realize the isolation and filtering functions of electrical signals. The isolation power module U3 includes a first bipolar push-pull converter, a first isolation transformer, and a first rectifier filter circuit. When configuring, select an isolation module with a power of 3W, and the corresponding output current is 600mA. The DC / DC power chip U2 includes a second bipolar push-pull converter, a second isolation transformer, a second rectifier filter circuit, a sampling circuit, a comparison circuit, a pulse width modulation circuit, an oscillator, and an adjustable reference voltage circuit. Through the feedback circuit, the output is determined. In the present invention, Vout = 3.2V. The specification of the DC / DC power chip is 1A@1.5MHz. The DC-DC power module is increasingly widely used in the fields of communication, network, industrial control, railway, military, etc. due to its significant features of small size, excellent performance, and convenient use. The application scenarios include power supply for various electronic devices, LED lighting, battery charging, etc. The power isolation module U3 is powered by 12V, first converted to 5V, preferably an isolation power module with a higher efficiency of 3w power consumption, and then the 5V is converted to a stable 3.3V through the DC / DC power chip U2. The reference voltage satisfies R1 = (Vout - 0.6V) × R2 ÷ 0.6V. Generally, R2 ≥ 100Ω, and R1 is about 450Ω. The embodiment of the present invention includes two parts. The first part is the single-cell battery simulator M0. The input is 12Vdc of the 12V power supply M4, which is converted to 5Vdc through the isolation power module U3, and the two electrical signals are also isolated. Then it is converted to 3.3Vdc through the DC / DC power chip, and finally filtered to remove the high-frequency 1.5MHz signal and control the ripple within a reasonable range, and output to the simulator output connector M1. The second part is a support board composed of the simulator output connector M1, the quick connection terminal group M2, the cell simulator plug-in group M3, the 12V power supply and power protection part M4, and the T1~T14 analog temperature part M5. Through measures such as vias, layout is realized to make the electrical signals arranged orderly and the wiring regular.

[0034] The DC / DC power chip U2 operates at 1.5MHz. Due to the solution, the output ripple is relatively large, about twenty millivolts according to the specification sheet. According to the requirements of Appendix B of the national standard GB / T34131-2023 for battery simulation devices, this is on the high side. The actual output voltage ripple is determined by the inductor current and the output impedance and consists of three parts, as Figure 4The composition of the DCDC output ripple is as follows: ① The voltage drop formed by the inductor current ripple through the parasitic resistance ESR of the output capacitor; ② The charging and discharging of the output capacitor; ③ The voltage mutation caused by the parasitic inductance. Referring to the power management technical article of TEXAS INSTRUMENTS, when the switching frequency and the inductance value are fixed, the most effective way to suppress the ripple voltage is to reduce the output impedance of the output capacitor at the switching frequency. The ripple filtering capacitor of the present invention adopts an aluminum electrolytic capacitor and a tantalum capacitor ( Figure 3 in which C6 is an aluminum electrolytic capacitor, C7 is a tantalum capacitor, C8 is a tantalum capacitor, C9 is a tantalum capacitor, C10 is a tantalum capacitor, C11 is a tantalum capacitor, and they are connected in parallel). The aluminum electrolytic capacitor is more lenient in terms of surge voltage limitation and can withstand greater voltage fluctuations. The aluminum electrolytic capacitor also has a lower ESR (equivalent series resistance) and ESL (equivalent series inductance), providing better high-frequency performance. The tantalum capacitor can provide a relatively large capacitance in a very small volume and is one of the types with the best volume-to-capacity ratio among known capacitors. The tantalum capacitor uses very fine tantalum powder sintered into a porous positive electrode, so the effective area per unit volume is large, and the dielectric constant of the tantalum oxide film is larger (about 25) than that of the aluminum oxide film (about 8 - 10). Therefore, under the conditions of the same withstand voltage and capacitance, the volume of the tantalum electrolytic capacitor is much smaller than that of the aluminum electrolytic capacitor. The tantalum capacitor can work stably in a relatively wide temperature range, usually applicable to -55°C to 125°C, or even a wider temperature range. It greatly reduces the output impedance, suppresses the 1.5 MHz high-frequency EMI, and suppresses the ripple to about one millivolt. A green light-emitting diode is connected in series, and the minimum lighting voltage is 2.3V. If the voltage is lower than 2.3V, the lamp does not light.

[0035] The maximum output currents of the isolated power supply module U3, the DCDC power chip U2, and the electrolytic capacitor determine the DCDC output current. It is preferred to select components with the same maximum output current. Ioutmax = MAX(600mA, 1A @ 1.5MHz, 560mA @ 100kHz) is approximately 560mA.

[0036] The common single-body analog power supply board is concentrated on the support board, but for the consideration of maintainability, a plug-in type is adopted. The support board uses a double-layer board, and vias are used in many places on the board for layout. It should be noted that the positions of the connectors for the single body and the support board are the same.

[0037] On the support board, a variety of power protection measures are adopted, including reverse connection prevention, anti-static, and surge protection measures. The reverse connection prevention uses the principle that a diode conducts forward and does not conduct backward. Considering the voltage drop of about 0.7V of the diode, generally, a 24-series monomer simulator can reach about 2A, with a power consumption of 1.4W, and the voltage will also be affected. Therefore, an ideal diode with MX74610T as the controller is used to reduce this power consumption, and the filter design will also eliminate the switching voltage loss of the switching tube. At the same time, the anti-static and surge protection uses 12V bidirectional electrostatic and surge protection (TVS / ESD), as Figure 5 shown.

[0038] For the basic temperature simulation requirements, a resistance scheme is adopted, and the common NTC specifications are 10kΩ and 100kΩ;

[0039] Facing the increasing voltage level requirements, about 30 series for 100V, now passenger cars reach the level of 900V, and large energy storage systems can reach even more. The support board is designed with four welding holes with an outer diameter of 5mm and an inner hole diameter of 3.5mm. Using hexagonal iron columns with a length of 7cm, if five layers are formed, the number of battery strings can reach 120 series. Also, because the output current is 560mA and the common passive balancing current range is 50mA to 200mA, according to the working principle of the AFE multi-channel voltage and temperature acquisition chip, with the same number of strings, the cell simulator can be reused, and the number of reusable strings can also be increased as the output current increases. At the same time, under the condition of active balancing, component selection needs to be done again, and the technical solution and working principle do not need to be changed.

[0040] As Figure 6 shown in the 2D drawing of the battery simulator tooling platform, this embodiment is an implementation scheme of a 24-series DCDC low-power battery simulator. It includes monomer battery simulators M0, simulator output connectors M1, quick-connect terminal groups M2, cell simulator plug-in groups M3, 12V power supply and power protection part M4, and T1 - T14 analog temperature part M5. There are a total of 24 monomer battery simulators M0, which are connected to the corresponding cell label positions of the cell simulator plug-in group M3 through the voltage output connectors of M0, such as Figure 3 the connectors of FH00843 in, and finally output to the simulator output connector M1, which is convenient for the test fixture design of the simulator wiring harness. In order to facilitate circuit inspection and customize the external cell transmission requirements (such as below 24 series), a quick-connect terminal group M2 is added. A voltage stabilization protection, anti-static, surge, and reverse connection prevention protection part, namely M4, is also designed for the 12V power supply on the tooling platform, and a T1 - T14 analog temperature part M5 is added to provide the demand for temperature simulation in the cell. The specific implementation is as follows

[0041] The simulator output connector M1 is one of the output ports for 24-series analog voltage and the only port for 14-series temperature analog point output. It uses a JAE connector of model MX34040NF2 for 40 series. For the specific connection, please refer to the schematic diagram. Optimizing the connection of this connector can better design the layout. Generally, this connector is used together with a 40-series standard female header wire harness tooling.

[0042] The quick-connect terminal group M2 is one of the output ports for 24-series analog voltage. It is a common six-pin three-terminal terminal. The order of the inner channels of the terminal is B0 to B24 from left to right. If there is no designed test wire harness tooling, it can be connected and used here. If there are problems with the voltage or calibration, it can also be detected here with a multimeter to check whether the output voltage of the single-cell simulator meets the requirements. The preferred quick-connect terminal model is XY119A-5.0-3P.

[0043] The cell simulator connector group M3 is the transfer point for the output single-cell voltage. It consists of 24 single-cell battery simulators, arranged in three rows. The order of each row is from left to right, namely B1 to B8, B9 to B16, and B17 to B24. The use of this connector can better detect single-cell problems of the battery simulator and is more repairable. Without changing the support board, it is convenient for the upgrade and replacement of the battery simulator. The preferred connector terminal model is 2.54-2*5P simple cow.

[0044] The 12V power supply and power protection part M4 includes a 3.5mm round power connector, 12V bidirectional electrostatic and surge protection (TVS / ESD), an ideal diode based on the MX74610T controller, and a six-pin three-terminal terminal. Pin 1 of the 3.5mm round power connector DC1 is connected to the 12V+ power input, and pins 2 and 3 are connected to GND (ground) to complete the electrical connection of the power input; one end of the TVS diode D1 is connected to the 12V+ power supply, and the other end is connected to GND for bidirectional electrostatic and surge protection to suppress overvoltage; pin 4 (ANODE) of the MX74610T controller U2 is connected to the source (S) of the external MOSFET and the 12V+ power supply, pins 5 (VCAPH) and 6 (VCAPL) are connected to both ends of the capacitor C25, pins 2 (GATE PD) and 3 (GATE) are connected to the gate (G) of the external MOSFET to quickly turn off in the case of reverse polarity, and pin 1 (CATHODE) is connected to the drain (D) of the external MOSFET and the 12V+ power supply. The ideal diode based on the MX74610T controller includes the MX74610T controller U2, the MOS transistor Q1 with a parasitic diode, and the capacitor C25. The MX74610T controller controls the conduction of the MOS transistor with a parasitic diode, and the power of the controller is generated by charging the capacitor C25 when the parasitic diode conducts. There will be a fluctuation in the output waveform, which is caused by the voltage drop of this parasitic diode. Generally, the charging time accounts for 2% of the overall time, and the voltage drop is 0.7V. A 3.5mm round power connector is preferred; 12V bidirectional electrostatic and surge protection (TVS / ESD) is preferred; the preferred controller model is MX74610T.

[0045] T1 to T14 analog temperature part M5, which is the output single-cell temperature point. The value of 10kΩ or 100kΩ is selected at 25°C and is placed alternately due to layout reasons.

[0046] According to the embodiments of the present invention Figure 2 , the specific implementation process is introduced below.

[0047] The embodiments of the present invention include two parts. The first part is the single-cell battery simulator M0. The input is 12Vdc from the 12V power supply and power protection part M4, which is converted to 5Vdc through the isolation power module U3, and the two electrical signals are also isolated. Then it is converted to 3.3Vdc through the DCDC power chip U2, and finally filtered to remove the high-frequency 1.5MHz signal and control the ripple within a reasonable range, and output to the simulator output connector M1. The second part is a support board composed of the simulator output connector M1, the quick connection terminal group M2, the cell simulator plug group M3, the 12V power supply and power protection part M4, and the T1 to T14 analog temperature part M5. Through measures such as vias, layout is used to achieve an orderly arrangement of electrical signals and regular wiring.

[0048] The specific implementation process of the first part of the embodiment of the present invention is as follows:

[0049] S11: The DC power supply passes through the input filter C5 and enters the isolated power supply module U3.

[0050] S12: The isolated power supply includes a first bipolar push-pull converter, a first isolation transformer, and a first rectifier filter circuit. When configuring, select an isolation module with a power of 3W, and the corresponding output current is 600mA.

[0051] S13: Then, it passes through the filter capacitors C4 and C2.

[0052] S14: Enter the DCDC power chip U2. This part includes a second bipolar push-pull converter, a second isolation transformer, a second rectifier filter circuit, a sampling circuit, a comparison circuit, a pulse width modulation circuit, an oscillator, and an adjustable reference voltage circuit. The output is determined through the feedback circuit. In the present invention, Vout = 3.2V. The specification of the DCDC power chip is 1A@1.5MHz.

[0053] S15: Setting of the feedback circuit R1 and R2. The reference voltage satisfies R1 = (Vout - 0.6V) × R2 ÷ 0.6V. Generally, R2 ≥ 100Ω, and R1 is about 450Ω.

[0054] S16: LC filtering link. The size of the output inductor L1 = Vout(1 - Vout / Vin,max) / (Fsw × Iout,max × 40%). Here, an inductor of 2.2uH is selected.

[0055] S17: It consists of an aluminum electrolytic capacitor (specification: 100uF, 560mA@100kHz) and a tantalum capacitor (specification: 22uF), a 1.5MHz ripple filtering link. According to the formula, the obtained ripple is about 2mV, and the maximum output current is 560mA, which is relatively low. To meet a greater output current requirement, the specifications of the isolated power supply module, the DCDC power chip, and the electrolytic capacitor can be increased. If it is an active balancing scenario, a bidirectional DCDC power chip module needs to be replaced. Generally, the active balancing current is 0.5A - 5A, and the change in components will be relatively large.

[0056] S18: Connect a green light-emitting diode in series. The minimum lighting voltage is 2.3V. If the voltage is lower than 2.3V, the lamp will not light up.

[0057] S19: Finally, output to the M0 connector FH-00843 for connecting to the support board.

[0058] The specific implementation process of the second part of the embodiment of the present invention is as follows:

[0059] S21: Power M4 with 12V. Through the 12V bidirectional electrostatic and surge (TVS / ESD) protection and reverse connection protection outside the DC power supply, a safe 12V is output. In case of reverse power supply connection, it is not affected by electrostatic interference at the power supply end and surge interference, and the operation is not affected. In particular, an ideal diode with MX74610T as the controller is adopted to reduce this power consumption, and the filtering design will also eliminate the small periodic voltage fluctuations caused by the switching voltage loss of the switching tube.

[0060] S22: The safe 12V is input to each cell simulator plug-in group M3. For the part with larger aggregated current, wiring with a wire diameter of 50 mil is adopted, and for most of the other parts, wiring with a wire diameter of 10 mil is adopted, and for some parts, wiring with a wire diameter of 25 mil is adopted.

[0061] S23: Each cell simulator plug-in group M3 outputs the single-cell battery simulator M0 converted to 3.3V, which is provided to the output connector M1 of the simulator and the quick-connect terminal group M2.

[0062] S24: T1 to T14 simulate the temperature part M5, which is composed of 10kΩ or 100kΩ resistors (which can be variable resistors, here are surface mount resistors), and all are output to the simulator output connector M1.

[0063] In this specification, each embodiment is described in a progressive manner. The key point of each embodiment is to illustrate the differences from other embodiments. For the same or similar parts among the embodiments, reference can be made to each other. For the device disclosed in the embodiment, since it corresponds to the method disclosed in the embodiment, the description is relatively simple, and reference can be made to the description in the method part for related parts.

[0064] The above description of the disclosed embodiments enables those skilled in the art to implement or use the present invention. Various modifications to these embodiments will be obvious to those skilled in the art, and the general principles defined herein can be implemented in other embodiments without departing from the spirit or scope of the present invention. Therefore, the present invention will not be limited to these embodiments shown herein, but will be accorded the widest scope consistent with the principles and novel features disclosed herein.

Claims

1. A low-power battery simulator based on DCDC, characterized in that, Including: A single cell simulator M0 and a support plate component. The single cell simulator M0 includes a filtering capacitor C5, a filtering capacitor C4, a filtering capacitor C2, an isolated power supply module U3, a DCDC power chip U2, an LC filtering circuit, and an M0 output connector. The filtering capacitor C5 receives a 12V DC voltage, filters the 12V DC voltage and then transmits it to the isolated power supply module U3; the isolated power supply module U3 converts the filtered DC voltage from 12V to 5V and isolates the electrical signal. The output end of the isolated power supply module U3 is connected to the filtering capacitors C4 and C2; the filtering capacitors C4 and C2 perform secondary filtering on the 5V DC voltage and then transmit it to the DCDC power chip U2; the DCDC power chip U2 converts the 5V DC voltage into a 3.3V DC voltage, and transmits the 3.3V DC voltage to the M0 output connector through the LC filtering circuit; the support plate component includes a simulator output connector M1, a quick connection terminal group M2, a cell simulator plug-in group M3, a 12V power supply and power protection part M4, and a T1-T14 analog temperature part M5, all of which are arranged on the support plate component; the M0 output connector is connected to the cell simulator plug-in group M3; the quick connection terminal group M2 receives the 3.3V DC voltage output by the cell simulator plug-in group M3; the 12V power supply and power protection part M4 provides a 12V voltage for the single cell simulator M0, and the T1-T14 analog temperature part M5 is used to simulate the cell temperature and is connected to the simulator output connector M1; the simulator output connector M1 receives the 3.3V DC voltage output by the cell simulator plug-in group M3 and the analog cell temperature output by the T1-T14 analog temperature part M5.

2. The low-power battery simulator based on DCDC according to claim 1, wherein The LC filtering circuit and the M0 output connector further include: a ripple filtering capacitor and a light emitting diode. The ripple filtering capacitor is connected to the output end of the inductor L1 in the LC filtering link to suppress 1.5MHz high-frequency EMI and reduce the output ripple; the light emitting diode is connected in series to the output end of the ripple filtering capacitor, with a minimum lighting voltage of 2.3V, and is used to indicate whether the circuit voltage is normal. The negative electrode of the light emitting diode is connected to the M0 output connector.

3. The low-power battery simulator based on DCDC according to claim 2, characterized in that, The model of the M0 output connector is FH00843.

4. A low-power battery simulator based on DCDC according to claim 1, characterized in that, There are 24 single cell simulators M0, which are connected to the cell simulator plug-in group M3 through the M0 output connector. There are three rows, and from left to right in each row are B1-B8, B9-B16, and B17-B24.

5. A low-power battery simulator based on DCDC according to claim 1, characterized in that The isolated power supply module U3 includes: a first bipolar push-pull converter, a first isolation transformer, and a first rectifier filter circuit. The first bipolar push-pull converter converts a 12V DC voltage into a high-frequency AC voltage; the first isolation transformer receives the high-frequency AC voltage output by the first bipolar push-pull converter and converts the voltage on the primary side to the secondary side through the principle of electromagnetic induction; the first rectifier filter circuit converts the voltage output by the first isolation transformer into a 5V DC voltage.

6. The low-power battery simulator based on DCDC according to claim 5, wherein The DCDC power chip U2 includes: a second bipolar push-pull converter, a second isolation transformer, a second rectifying and filtering circuit, a sampling circuit, a comparison circuit, a pulse width modulation circuit, an oscillator, an adjustable reference voltage circuit, and a feedback circuit. The second bipolar push-pull converter, the second isolation transformer, the second rectifying and filtering circuit, the sampling circuit, and the comparison circuit are connected in sequence; the oscillator provides a clock signal for the pulse width modulation circuit; the adjustable reference voltage circuit provides a reference voltage for the pulse width modulation circuit; the second rectifying and filtering circuit feeds back the output voltage to the adjustable reference voltage circuit through the feedback circuit.

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