A mobile power intelligent balance charging management and control circuit
Patent Information
- Application Number
- CN202521949597.4
- Authority / Receiving Office
- CN · China
- Patent Type
- Utility models(China)
- Current Assignee / Owner
- Filing Date
- 2025-09-11
- Publication Date
- 2026-10-23
- Estimated Expiration
- 2035-09-11
AI Technical Summary
然而，这类方案在升压对外供电与降压对电池充电之间切换时，由于电感电流方向无法瞬时改变，需要额外的检测与等待时间，导致模式转换慢（毫秒级）、输出电压跌落大，且必须限制负载电流以维持平稳功率流，系统功率密度和动态响应受限
借助第一、第二辅助功率管为电感电流提供可控续流路径，在升压/降压模式转换时无需等待电感能量完全释放即可立即反向，切换过程可在1个开关周期内完成，远快于传统毫秒级方案。
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Figure CN224890356U_ABST
Abstract
Description
Technical Field
[0001] This utility model relates to the field of charging circuit technology, and in particular to a smart balanced charging management and control circuit for mobile power supplies. Background Technology
[0002] To achieve simultaneous charging and discharging and battery pack balancing, existing power banks typically employ dedicated ICs (such as BQ24610 and ZS6366) in conjunction with multiple bypass resistors or Buck / Boost cascaded topologies to perform trickle-constant-constant voltage charging of the battery. They balance each cell through voltage sampling and bypass discharge. However, when switching between boosting for external power supply and bucking for battery charging, this approach requires additional detection and waiting time because the inductor current direction cannot change instantaneously. This results in slow mode transitions (milliseconds), large output voltage drops, and the need to limit load current to maintain a stable power flow, thus limiting system power density and dynamic response. Summary of the Invention
[0003] The purpose of this invention is to overcome the shortcomings of the prior art and provide a mobile power bank intelligent balanced charging management and control circuit, aiming to provide a compact circuit structure that can realize intelligent balanced charging management and ultra-fast bidirectional switching inside the mobile power bank.
[0004] To achieve the above objectives, the following solution is adopted: A mobile power bank intelligent balanced charging management and control circuit includes a first power transistor, a second power transistor, a third power transistor, a first auxiliary power transistor, and a second auxiliary power transistor, all triggered by a chip. It also includes a power capacitor, an output capacitor, a first inductor, a second inductor, and a battery. The power capacitor is connected in parallel across the two ends of the battery, and the output capacitor is connected in parallel across the power output terminal of the control circuit. One end of the first power transistor is connected to one end of the first inductor, and the other end is connected to the second inductor and one end of the second auxiliary power transistor. One end of the second power transistor is connected to the other end of the first inductor and the battery, and the other end is connected to the other end of the second inductor. One end of the third power transistor is connected between the first inductor and the first power transistor, and the other end is connected to the output capacitor. The first auxiliary power transistor and the second auxiliary power transistor are connected and located between the battery and the first power transistor.
[0005] Furthermore, the control circuit operates in boost mode, in which the first power transistor and the second power transistor are turned on, the third power transistor is turned off, and after one switching cycle, the first power transistor and the second power transistor are turned off, and the third power transistor is turned on.
[0006] Furthermore, when the control circuit operates in the boost mode, the battery charges the first inductor and the second inductor, and the output capacitor outputs power to the power output terminal; after one switching cycle, the first inductor and the second inductor charge the output capacitor and output power to the power output terminal.
[0007] Furthermore, the control circuit operates in buck mode, in which the third power transistor is turned on, the first power transistor and the second power transistor are turned off, and after one switching cycle, the first power transistor and the second power transistor are turned on, and the third power transistor is turned off.
[0008] By adopting the above solution, the beneficial effects of this utility model are: By using the first and second auxiliary power transistors to provide a controllable freewheeling path for the inductor current, the switching can be completed immediately without waiting for the inductor energy to be fully released during the boost / buck mode transition. The switching process can be completed within one switching cycle, which is much faster than the traditional millisecond-level solution. Attached Figure Description
[0009] Figure 1 This is a schematic diagram of the intelligent balanced charging management and control circuit for mobile power supplies according to this utility model. Figure 2 The waveform diagram shows the intelligent balanced charging management and control circuit of the mobile power supply of this utility model operating in boost mode. Figure 3 This is a schematic diagram of the current flow path of the intelligent balanced charging management and control circuit for mobile power supplies of this utility model when operating in boost mode. Figure 4 Another schematic diagram of the current flow path of the intelligent balanced charging management and control circuit of the mobile power supply of this utility model in boost mode. Figure 5 The waveform diagram shows the intelligent balanced charging management and control circuit of the mobile power supply of this utility model operating in buck mode. Figure 6 This is a schematic diagram of the current flow path of the intelligent balanced charging management and control circuit for mobile power supply of this utility model when operating in buck mode. Figure 7Another schematic diagram of the current flow path of the intelligent balanced charging management and control circuit of the mobile power supply of this utility model in buck mode. Figure 8 This is a timing diagram showing the transition state from boost mode to buck mode for the intelligent balanced charging management and control circuit of the mobile power supply of this utility model. Figure 9 This is a timing diagram showing the transition state from buck mode to boost mode for the intelligent balanced charging management and control circuit of the mobile power supply of this utility model. Detailed Implementation
[0010] The technical solutions of the present utility model will be clearly and completely described below with reference to the accompanying drawings of the embodiments. Obviously, the described embodiments are only some embodiments of the present utility model, and not all embodiments. Based on the embodiments of the present utility model, all other embodiments obtained by those of ordinary skill in the art without creative effort are within the protection scope of the present utility model.
[0011] Reference Figure 1 As shown, this utility model provides a mobile power bank intelligent balanced charging management and control circuit, including a first power transistor S1, a second power transistor S2, a third power transistor S3, a first auxiliary power transistor SAux1, and a second auxiliary power transistor SAux2, all controlled and triggered by a chip. It also includes a power capacitor Cbat, an output capacitor Cbus, a first inductor L1, a second inductor L2, and a battery Vbat. The power capacitor Cbat is connected in parallel across the battery Vbat, and the output capacitor Cbus is connected in parallel across the power output terminal of the control circuit. The first power... One end of power transistor S1 is connected to one end of the first inductor L1, and the other end is connected to one end of the second inductor L2 and the second auxiliary power transistor SAux; one end of the second power transistor S2 is connected to the other end of the first inductor L1 and the battery Vbat, and the other end is connected to the other end of the second inductor L2; one end of the third power transistor S3 is connected between the first inductor and the first power transistor S1, and the other end is connected to the output capacitor Cbus; the first auxiliary power transistor SAux1 and the second auxiliary power transistor SAux are connected and located between the battery and the first power transistor.
[0012] In one embodiment, the control circuit operates in boost mode, in which the first power transistor S1 and the second power transistor S2 are turned on, the third power transistor S3 is turned off, and after one switching cycle, the first power transistor S1 and the second power transistor S2 are turned off, and the third power transistor S3 is turned on.
[0013] When the control circuit operates in boost mode, the battery Vbat charges the first inductor L1 and the second inductor L2, and the output capacitor Cbus outputs power to the power output terminal; after one switching cycle, the first inductor L1 and the second inductor L2 charge the output capacitor Cbus and output power to the power output terminal.
[0014] In one embodiment, the control circuit operates in buck mode, in which the third power transistor S3 is turned on, the first power transistor S1 and the second power transistor S2 are turned off, and after one switching cycle, the first power transistor S1 and the second power transistor S2 are turned on, and the third power transistor S3 is turned off.
[0015] Explanation of the principle: To simplify circuit analysis, we assume that the control circuit operates in a steady state and under CCM conditions. During operation, we consider the body diodes of the first power transistor S1, the second power transistor S2, the third power transistor S3, the first auxiliary power transistor SAux1, and the second auxiliary power transistor SAux2. The corresponding diodes are DS1, DS2, DS3, DSAux1, and DSAux2. The capacitances of Cbat and Cbus are large enough to be considered as constant voltage sources.
[0016] When in boost mode, such as Figure 2-4 As shown, at time t0, power transistors S1 and S2 are turned on, and S3 is turned off. Figure 3 The current flow path in this mode is shown. Inductors L1 and L2 are charged by the battery voltage Vbat, which causes the inductor currents iL1 and iL2 to increase linearly, and the output capacitor Cbus provides energy to the output load. vL1 and vL2 are the voltages across inductors L1 and L2, respectively. The rates of change of iL1 and iL2 during this period can be derived.
[0017] At time t1, which is one switching cycle later, when power transistor S3 turns on, power transistors S1 and S2 turn off. The current path at this time is as follows: Figure 4 As shown, the battery voltage Vbat and the energy stored in inductors L1 and L2 begin to charge the output capacitor Cbus and transfer energy to the output load. During this period, the inductor currents iL1 and iL2 decrease linearly, and the rates of change of iL1 and iL2 can be derived.
[0018] When in buck mode, such as Figure 5 The waveform diagram shown illustrates that at time t0, when S3 is on, S1 and S2 are off, and the current flow path is as follows: Figure 6 As shown. In this mode, inductors L1 and L2 and power supply capacitor Cbat are connected in series and charged by DC voltage Vdc and bus. Therefore, the inductor currents iL1 and iL2 decrease linearly.
[0019] At time t1, when S3 is turned off, S1 and S2 are turned on. The current path at this time is as follows: Figure 7 As shown, inductors L1 and L2 and power supply capacitor Cbat release energy to the battery voltage Vbat, causing the inductor currents iL1 and iL2 to increase linearly.
[0020] As a supplement, the transition states from boost mode to buck mode and from buck mode to boost mode require direction control because the direction of inductor current or capacitor voltage cannot be reversed immediately.
[0021] To achieve power flow control of the bidirectional converter, the state of the conversion signal received by the chip is first detected to determine whether the circuit needs to change its operating mode. Then, the gate drive signals of auxiliary power transistors SAux1 and SAux2 maintain their original operating modes until the inductor currents iL1 and iL2 demagnetize to zero. Next, the gate drive signals of auxiliary power transistors SAux1 and SAux2 change their original operating modes. Finally, the gate drive signals of power transistors S1, S2, and S3 are restored.
[0022] Specifically, for circuits operating in continuous conduction mode (CCM), the drive signals for all power transistors during the switching process are as follows: Figure 8 The diagram illustrates the conversion process and the timing sequence from boost mode to buck mode. For circuits operating in discontinuous conduction mode (BCM) or discontinuous conduction mode (DCM), the conversion occurs when the inductor current is zero. During the conversion phase, S3 conducts for one switching cycle, providing a path for the freewheeling current in the inductor. Inductor currents iL1 and iL2 decrease linearly until the inductor current demagnetizes to zero. Auxiliary power transistors SAux1 and SAux2 return to their original operating modes. After time t2, the gate drive signals of power transistors S1, S2, and S3 are restored, the circuit enters buck mode, and inductors L1 and L2 begin storing energy.
[0023] Specifically, during the state transition from buck mode to boost mode, the gate drive signals of all power switches change as follows during the transition: Figure 9 As shown. During the conversion phase, S3 is turned off, and auxiliary power transistors SAux1 and SAux2 maintain their original operating modes. Subsequently, S1 and S2 are turned on for two switching cycles, providing a path for the freewheeling current of the inductor. The inductor currents iL1 and iL2 increase linearly until the inductor current demagnetizes to zero. Auxiliary power transistors SAux1 and SAux2 then return to their original operating modes. After time t3, the gate drive signals of S1, S2, and S3 are restored, the circuit enters boost mode, and inductors L1 and L2 begin to store energy.
[0024] This invention utilizes the first and second auxiliary power transistors to provide a controllable freewheeling path for the inductor current. When switching between boost and buck modes, it can immediately reverse without waiting for the inductor energy to be fully released. The switching process can be completed within one switching cycle, which is much faster than traditional millisecond-level solutions.
[0025] Finally, it should be noted that the above embodiments are only used to illustrate the technical solutions of this utility model, and not to limit it. Although this utility model has been described in detail with reference to the foregoing embodiments, those skilled in the art should understand that modifications can still be made to the technical solutions described in the foregoing embodiments, or equivalent substitutions can be made to some of the technical features. Such modifications or substitutions do not cause the essence of the corresponding technical solutions to deviate from the spirit and scope of the technical solutions of the embodiments of this utility model.
Claims
1. A mobile power bank intelligent balanced charging management and control circuit, characterized in that, The system includes a first power transistor, a second power transistor, a third power transistor, a first auxiliary power transistor, and a second auxiliary power transistor, all controlled and triggered by a chip. It also includes a power capacitor, an output capacitor, a first inductor, a second inductor, and a battery. The power capacitor is connected in parallel across the battery, and the output capacitor is connected in parallel across the power output terminal of the control circuit. One end of the first power transistor is connected to one end of the first inductor, and the other end is connected to the second inductor and one end of the second auxiliary power transistor. One end of the second power transistor is connected to the other end of the first inductor and the battery, and the other end is connected to the other end of the second inductor. One end of the third power transistor is connected between the first inductor and the first power transistor, and the other end is connected to the output capacitor. The first auxiliary power transistor and the second auxiliary power transistor are connected and located between the battery and the first power transistor.