RLC (Radio Link Control)-based oscillation type self-adaptive energy transfer active equalization system

Abstract

The invention discloses an RLC-based oscillation-type adaptive energy transfer active equalization system, and the system comprises a system power supply which is used for providing a working voltage for each unit of the system; the PWM signal generation circuit is used for generating a PWM signal generation circuit signal; the input end of the synchronous driving circuit is connected with the output end of the PWM signal generating circuit; n electrochemical energy storage devices connected in series, wherein n is an integer greater than or equal to 2; n RL bidirectional oscillation damping circuits, wherein each RL bidirectional oscillation damping circuit is connected with one corresponding electrochemical energy storage device; n double-MOS push-pull level conversion circuits, wherein the output end of each double-MOS push-pull level conversion circuit is connected with one corresponding RL bidirectional oscillation damping circuit; and (n-1) high-frequency oscillation capacitors, wherein each high-frequency oscillation capacitor is connected between two adjacent double-MOS push-pull level conversion circuits.

Description

Technical Field

[0001] This invention relates to the field of electrochemical energy storage technology, specifically to an oscillating adaptive energy transfer active balancing system based on RLC. Background Technology

[0002] With the increasing global energy shortage and the continuous development of the new energy industry in recent years, the use of electrochemical devices has also increased rapidly. These include various types of lithium batteries, lead-acid batteries, supercapacitors, lithium-ion capacitors, and large-capacity electrolytic capacitors.

[0003] In most energy storage device series applications, voltage balancing methods are usually used to reduce the cumulative voltage deviation caused by errors in the manufacturing process of the energy storage devices.

[0004] In supercapacitor series applications, the common methods for voltage equalization are direct parallel connection of resistors and resistor-limited discharge equalization. The disadvantages are twofold: firstly, the direct parallel connection of resistors increases the leakage current of individual supercapacitor cells; secondly, the voltage-limited discharge method is only effective above the supercapacitor's overvoltage point and is ineffective within the normal operating range. Furthermore, during charging, the current from this voltage-limited discharge equalization method is very small, resulting in a weak equalization effect and inability to achieve the equalization target promptly.

[0005] In series applications of electrolytic capacitors, voltage equalization is typically achieved by directly connecting resistors in parallel or by using transistors for constant current equalization. Both of these equalization methods have the disadvantage of power loss and, in practical applications, can cause localized overheating of the circuit board.

[0006] In series applications of lithium-ion capacitors, a two-stage voltage-limiting combination is typically used. A first-stage low-current discharge equalization is initiated above the over-discharge voltage point of each individual cell, and a second-stage high-current discharge equalization is initiated above the over-discharge voltage point of each individual cell. While this combination achieves voltage equalization among the individual cells, it results in long-term loss of usable energy.

[0007] In various lithium battery series applications, the theoretically usable balancing methods currently known include: resistive discharge balancing, multi-winding parallel balancing of isolation transformers, bidirectional step-up / step-down balancing of inductors, and capacitor switching combination balancing. The current status and shortcomings of existing theoretical battery balancing methods are analyzed below:

[0008] 1. Resistive discharge equalization is currently the most common method used in the battery industry. It is usually combined with the BMS system to achieve dynamic discharge. The advantage of this method is that it is cheap and easy to implement. However, its disadvantage is that the energy loss of the entire system is large. In addition, the commonly used time-division multiplexing resistor discharge equalization method will affect the acquisition of the individual cell voltage, thus affecting the accuracy of the BMS in acquiring the individual cell voltage.

[0009] 2. While theoretically feasible, the parallel winding balancing method for isolation transformers has proven difficult to implement in practice over the past few decades in the battery industry. Issues such as core material structure, winding process, magnetic tangential interference, and magnetic circuit misalignment due to various factors make it challenging to achieve consistent electromotive forces (EMFs) across the passive secondary windings. This is particularly true in conventional epoxy core structures, where true consistency is almost impossible to achieve. Even toroidal cores made with special materials and processes suffer from large size, low space utilization, and difficult-to-control winding processes. Therefore, this method, proposed decades ago, has not been widely adopted in practical applications.

[0010] 3. Inductive bidirectional buck-boost balancing: This method involves connecting an inductor to each battery lead, followed by a series of MOSFETs. Each pair of adjacent cells, along with the MOSFET and inductor at the midpoint, forms a typical half-bridge buck-boost circuit. When a cell's voltage is too high, it operates in buck mode, continuously transferring energy from the high-voltage battery to the adjacent low-voltage battery, achieving battery balancing. This method requires energy to undergo an electromagnetic conversion process, resulting in low conversion efficiency, electromagnetic interference, and voltage-type pulse interference due to the inherent characteristics of the inductor. It is also costly. However, it has seen some application in real-world projects.

[0011] 4. Capacitor-Switch Combination Balancing: This method uses a combination of low-frequency electronic switches to directly charge a large-capacity capacitor from the high-voltage battery. When the voltage reaches the high-voltage battery level, the switch is activated to allow the capacitor to recharge the low-voltage battery, achieving battery voltage balancing. This method typically uses NMOS transistors as switching devices, resulting in complex drive circuits. For example, in our previous two patents regarding battery balancing using a combination of supercapacitors and MOS electronic switches, we found in practical applications that regardless of whether a supercapacitor or an electrolytic capacitor is used as the transition capacitor, the transient current during switching is large. This places high current stress requirements on the MOS switches and also affects battery lifespan. Due to the complexity of the drive circuit and the presence of large transient currents, this method is difficult to promote in practical applications.

[0012] All of the above equalization methods require closed-loop integration with specialized control chips or MUCs to achieve their functionality, and each has certain inherent limitations. How to achieve automatic equalization of energy storage devices across the entire voltage range with a relatively simple circuit design at a low cost, capable of independent use or integration with BMS or CMS systems, is a topic worthy of our research.

[0013] In recent years, within the various energy storage devices mentioned above, an increasing number of individual cells have adopted a cylindrical design with electrodes at both ends. Modules composed of these cells have half of their individual electrodes evenly distributed across both sides; these electrodes are essential voltage sampling points for the system. The wiring between these sampling points and the equalization circuit is complex, and due to the requirements of the equalization current, the sampling lines must also possess a certain overcurrent capability, thus limiting their wire diameter. Therefore, while researching new equalization technologies, we must also consider how to further simplify the application structure. Summary of the Invention

[0014] The purpose of this invention is to provide an oscillating adaptive energy transfer active balancing system based on RLC, which aims to solve one of the technical problems in the background art.

[0015] To achieve the above objectives, the present invention adopts the following technical solution:

[0016] An oscillating adaptive energy transfer active balancing system based on RLC, comprising:

[0017] The system power supply is used to provide operating voltage to each unit of the system;

[0018] A PWM signal generation circuit is used to generate PWM signal signals.

[0019] A synchronous drive circuit, the input of which is connected to the output of the PWM signal generation circuit;

[0020] n electrochemical energy storage devices connected in series, where n is an integer greater than or equal to 2;

[0021] n RL bidirectional oscillation damping circuits, each of the RL bidirectional oscillation damping circuits being connected to a corresponding electrochemical energy storage device;

[0022] n dual MOS push-pull level conversion circuits, the output of each dual MOS push-pull level conversion circuit is connected to a corresponding RL bidirectional oscillation damping circuit;

[0023] n-1 high-frequency oscillation capacitors, each of which is connected between two adjacent dual MOS push-pull level conversion circuits;

[0024] The n output terminals of the synchronous drive circuit are respectively connected to the control terminals of the n dual MOS push-pull level conversion circuits. The PWM signal generated by the PWM signal generation circuit drives all the dual MOS push-pull level conversion circuits to perform switching operations with the same frequency and phase through the synchronous drive circuit. This causes the high-frequency oscillation capacitor, the RL bidirectional oscillation damping circuit, and the electrochemical energy storage device to form an RLC oscillation network. The network's resonance and damping characteristics enable adaptive adjustment of the equalization current, thereby achieving energy transfer and voltage equalization among the series-connected electrochemical energy storage devices.

[0025] In some optional implementations, the system power supply adopts an internal energy storage self-powered method or an external power supply method.

[0026] In some alternative implementations, the system power supply is configured as a switching buck power supply or a linear regulated power supply.

[0027] In some alternative implementations, the PWM signal generation circuit includes a dedicated clock generation integrated circuit, an active crystal oscillator, a microcontroller, a digital signal processor, or a control unit of a battery management system.

[0028] In some alternative implementations, the synchronous drive circuit employs non-isolated drive, optically isolated drive, magnetically isolated drive, or charge-isolated drive methods.

[0029] In some alternative implementations, the synchronous drive circuit employs a cascaded extended synchronous drive method.

[0030] In some alternative implementations, the high-frequency oscillation capacitor is a ceramic capacitor, a tantalum capacitor, an electrolytic capacitor, or a film capacitor.

[0031] In some alternative implementations, the switching device in the dual MOS push-pull level conversion circuit is a MOS transistor, a triode, an IGBT, a silicon carbide MOS transistor, or a gallium nitride MOS transistor.

[0032] In some alternative implementations, the RL bidirectional oscillation damping circuit is an RL series circuit, an RL parallel circuit, a single inductor, a single resistor, or a single positive temperature coefficient thermistor.

[0033] In some alternative embodiments, the electrochemical energy storage device is a supercapacitor, an electrolytic capacitor, a lithium battery, a lithium-ion capacitor, a sodium-ion battery, a sodium-ion capacitor, or a lead-acid battery.

[0034] Compared with the prior art, the present invention has the following significant advantages:

[0035] To address the issues of low efficiency, high losses, and complex structure in traditional equalization methods, a globally synchronized energy exchange network is constructed by setting up a synchronous drive circuit and a dual-MOS push-pull level conversion circuit operating at the same frequency and phase, and utilizing a high-frequency oscillating capacitor as a direct energy transport carrier. This avoids the losses caused by multiple energy conversions (such as electro-magnetic-electric), achieving highly efficient direct energy transfer.

[0036] Achieving full-voltage-range adaptive equalization without complex control: By integrating an RL bidirectional oscillating damping circuit into the branch of each energy storage device, and forming an RLC oscillation network together with a high-frequency oscillating capacitor, the dynamic impedance characteristics of this network allow the equalization current to automatically adjust according to the real-time voltage difference between the energy storage devices. When the voltage difference is large, the resonant current amplitude is large, and the equalization speed is fast; when the voltage difference is small, the current amplitude automatically decreases to avoid over-equalization. This solves the complexity of traditional methods that require an MCU to detect voltage and calculate control quantities, achieving open-loop adaptive equalization.

[0037] Suppressing transient shocks and improving system reliability: The resistive or inductive components in the RL bidirectional oscillation damping circuit can effectively suppress the surge current generated during the switching of dual MOS switches due to the mismatch between capacitor voltage and battery voltage, protecting the MOS switches and energy storage devices, and improving the long-term reliability of the system.

[0038] Simplified system architecture and enhanced applicability: All the above circuit units (system power supply, PWM generator, synchronous drive, switches, capacitors, dampers) can be implemented using standard general-purpose components, eliminating the need for special winding transformers or complex multi-channel independent power supplies. The entire system architecture is clear and easy to integrate into various battery management systems (BMS) or operate independently, suitable for a variety of electrochemical energy storage devices from supercapacitors to lithium batteries. Attached Figure Description

[0039] Figure 1 This is a block diagram of the single system composition of the present invention (serial first-order oscillation equalization system);

[0040] Figure 2 This is a block diagram of the system composition of the present invention (parallel first-order oscillatory equalization system). Detailed Implementation

[0041] To make the objectives, technical solutions, and advantages of this application clearer, the technical solutions in the embodiments of this application will be described in more detail below with reference to the accompanying drawings. In the drawings, the same or similar reference numerals denote the same or similar components or components having the same or similar functions throughout. The described embodiments are some, but not all, of the embodiments of this application. The embodiments described below with reference to the accompanying drawings are exemplary and intended to explain this application, and should not be construed as limiting this application. All other embodiments obtained by those skilled in the art based on the embodiments of this application without creative effort are within the scope of protection of this application.

[0042] The purpose of this invention is to overcome the shortcomings of existing technologies and provide an RLC-based oscillating adaptive energy transfer active balancing system. This system utilizes a PWM signal generator circuit to synchronously control a switching network, combining a high-frequency oscillating capacitor, an RL damping circuit, and energy storage devices to form an RLC oscillating network. Through the network's resonance and damping characteristics, the balancing current is adaptively adjusted, achieving efficient and lossless energy transfer and voltage balancing between series-connected energy storage devices. It features simple structure, strong adaptability, wide applicability, and low loss.

[0043] This invention is applicable to the purpose of individual energy transfer adaptive voltage equalization of any electrochemical energy storage device and its energy detection and management system. It is also applicable to the purpose of high-voltage equalization between any electrochemical energy storage packs.

[0044] An RLC-based oscillating adaptive energy transfer active balancing system includes: a system power supply for providing operating voltage to each unit of the system; a PWM signal generation circuit for generating PWM signal; a synchronous drive circuit whose input is connected to the output of the PWM signal generation circuit; n series-connected electrochemical energy storage devices, where n is an integer greater than or equal to 2; n RL bidirectional oscillation damping circuits, each RL bidirectional oscillation damping circuit connected to a corresponding electrochemical energy storage device; n dual MOS push-pull level conversion circuits, each dual MOS push-pull level conversion circuit whose output is connected to a corresponding RL bidirectional oscillation damping circuit; and n-1 high-frequency oscillation capacitors, each high-frequency oscillation capacitor connected between two adjacent dual MOS push-pull level conversion circuits.

[0045] The n output terminals of the synchronous drive circuit are respectively connected to the control terminals of the n dual MOS push-pull level conversion circuits. The PWM signal generated by the PWM signal generation circuit drives all the dual MOS push-pull level conversion circuits to perform switching operations with the same frequency and phase through the synchronous drive circuit. This causes the high-frequency oscillation capacitor, the RL bidirectional oscillation damping circuit, and the electrochemical energy storage device to form an RLC oscillation network. The network's resonance and damping characteristics enable adaptive adjustment of the equalization current, thereby achieving energy transfer and voltage equalization among the series-connected electrochemical energy storage devices.

[0046] The main idea is to use a PWM signal generation circuit to control a dual MOS push-pull level conversion circuit, employing a high-frequency oscillating capacitor and an RL bidirectional oscillating damping circuit as energy transfer containers. Simultaneously, the current damping effect of the resistor is used to suppress transient energy, achieving the goal of RLC oscillating adaptive equalization. This enables synchronous energy transfer across all energy storage devices, generating an oscillating effect throughout the energy storage string and achieving adaptive dynamic equalization of the electrochemical energy storage devices.

[0047] The system power supply converts the total voltage of the energy storage system into the low-voltage power required for the normal operation of each sub-functional unit. The PWM signal generation circuit can be an independent PWM signal generation circuit, or it can be a fixed high-frequency or variable PWM signal generation circuit generated by the BMS or CMS control circuit. The synchronous drive circuit is responsible for driving the MOS in each dual-MOS push-pull level conversion circuit and limiting the drive capability strength to ensure sufficient state transition time for the dual MOS.

[0048] The high-frequency oscillation capacitor is a ceramic capacitor of varying capacity selected based on the type and capacity of the target electrochemical energy storage device. Its function is to achieve high-frequency energy transfer under high-frequency control. The dual MOS push-pull level conversion circuit controls the level of the corresponding high-frequency oscillation capacitor connection point. The RL bidirectional oscillation damping circuit can be configured in RL series, with a single inductor, a single conventional resistor, or a PTC configuration. Its function is twofold: firstly, to suppress instantaneous large currents; and secondly, to achieve energy transfer through transient resonance between the inductor and the high-frequency oscillation capacitor, thus achieving a balanced current adaptive effect. The composition of this unit depends on the specific energy storage device and structure. The electrochemical energy storage device is the core of the target energy storage system and can be any existing lithium battery, lead-acid battery, supercapacitor, lithium-ion capacitor, electrolytic capacitor, or any future independent electrochemical energy storage device.

[0049] During system operation, the PWM signal generation circuit generates a fixed or variable PWM signal. This signal, after power amplification and synchronization processing by the synchronous drive circuit, simultaneously drives all dual-MOS push-pull level conversion circuits to perform completely synchronized and in-phase switching operations. When all dual-MOS circuits are synchronously turned on, each high-frequency oscillating capacitor forms a charging or discharging loop with adjacent energy storage devices through its corresponding RL damping circuit; when all dual-MOS circuits are synchronously turned off, the loop state switches. This globally synchronized switching action allows energy to be transferred bidirectionally between adjacent energy storage devices via the high-frequency oscillating capacitors. Because the entire network exhibits RLC oscillation characteristics, the magnitude and direction of its balancing current are determined by the instantaneous voltage difference and RLC parameters at each point in the network. Without external voltage sampling and closed-loop control, energy can be automatically transferred from higher-voltage energy storage devices to lower-voltage energy storage devices, achieving adaptive dynamic balancing.

[0050] To ensure the balancing system continues to operate even when the main power supply to the energy storage system is disconnected, such as in a static state, an internal energy storage self-powered mode is implemented, drawing power from the main series battery pack and storing it in a local capacitor. Simultaneously, to meet the needs of the initial power-on phase or high-power balancing requirements, an external power supply mode is also supported. This dual-mode power supply design enhances the system's environmental adaptability and operational continuity.

[0051] To efficiently convert the relatively high total voltage of the energy storage system (e.g., tens to hundreds of volts) to the low voltage required by the control circuit (e.g., 5V, 3.3V), while balancing efficiency and cost, the system power supply is set as a switching buck power supply (e.g., a BUCK circuit), which has high conversion efficiency. In low-dropout or noise-sensitive scenarios, a linear regulated power supply can also be used, which has low ripple and simple circuitry.

[0052] In order to generate stable and accurate PWM signal generation circuit signals and adapt to the integration and cost requirements of different application scenarios, in some embodiments, the PWM signal generation circuit includes a dedicated clock generation integrated circuit, an active crystal oscillator, a microcontroller, a digital signal processor, or a control unit of a battery management system.

[0053] The PWM signal generation circuit can be configured with multiple options. A dedicated clock chip or active crystal oscillator can provide a high-precision fixed frequency for independent equalization modules. A microcontroller or DSP can generate PWM signals with adjustable frequency and duty cycle, facilitating intelligent control. Integration with the BMS main control unit maximizes the use of existing resources and simplifies the overall design.

[0054] Preferably, the PWM signal generation circuit uses an LTC6900CS5 clock oscillator chip in the independent equalization circuit, and is generated by an MCU in the BMS or CMS system.

[0055] To ensure that the PWM signal can reliably and quickly drive multiple dual-MOS push-pull level conversion circuits at different potentials (floating ground), and considering system isolation withstand voltage and cost, in some embodiments, the synchronous drive circuit adopts non-isolated drive, opto-isolated drive, magnetically isolated drive, or charge-isolated drive methods. For example, the synchronous drive circuit is implemented using a single-transistor low-side driver chip of model MCP1416RT in conjunction with a current-limiting resistor.

[0056] The synchronous drive circuit can be configured with various driving methods. Non-isolated drive has the lowest cost and is suitable for applications where all MOSFETs share a common ground or have similar potentials. Optocoupler isolation, magnetic isolation (such as isolation drivers), or capacitor isolation (charge isolation) methods can achieve high-voltage isolation, ensuring the safety of the high-voltage side and the low-voltage control side, and are suitable for high-voltage battery systems.

[0057] In some embodiments, to address the problem that a large number of MOSFETs need to be driven in a large series battery pack (e.g., when n is very large), but the driving capability of a single driving chip is insufficient, the synchronous driving circuit adopts a cascaded expansion synchronous driving method. That is, the output of the previous stage driving chip, in addition to driving some MOSFETs, also serves as a signal source to drive the next stage driving chip, thereby progressively expanding the driving capability and ensuring that all MOSFETs can still achieve precise synchronization.

[0058] In some embodiments, the high-frequency oscillation capacitor is a ceramic capacitor, a tantalum capacitor, an electrolytic capacitor, or a film capacitor. To achieve efficient energy transfer during high-frequency switching while minimizing its own losses, the high-frequency oscillation capacitor is preferably a high-frequency ceramic capacitor (such as NPO or X7R material), which has a low equivalent series resistance (ESR) and good high-frequency characteristics.

[0059] To perform high-speed switching and achieve level conversion, and to select appropriate devices based on system voltage, current, and switching frequency requirements, various types of switching devices are configured. In some embodiments, the switching devices in the dual MOS push-pull level conversion circuit are MOSFETs, transistors, IGBTs, silicon carbide MOSFETs, or gallium nitride MOSFETs.

[0060] Dual MOS push-pull level conversion circuits are low-cost and suitable for most applications. IGBTs are suitable for higher voltages. Silicon carbide (SiC) MOS transistors or gallium nitride (GaN) MOS transistors have extremely low switching losses and on-resistance, making them suitable for ultra-high frequency and high-efficiency applications. For example, using an integrated PMOS+NMOS surface-mount packaged pair of MOS transistors, model FDD8424H, ensures consistent electrical performance during dual-level conversion.

[0061] To achieve the dual functions of damping and resonance participation, and to optimize for energy storage systems with different capacities and safety requirements, the specific form of the RL bidirectional oscillation damping circuit is configured in various ways. In some embodiments, the RL bidirectional oscillation damping circuit is an RL series circuit, an RL parallel circuit, a single inductor, a single resistor, or a single positive temperature coefficient thermistor. For example, the RL bidirectional oscillation damping circuit uses a single conventional resistor in small-capacity systems, a surface-mount power-type self-resetting PTC in medium-capacity systems, and a PTC in series with an inductor or a single inductor in large-capacity systems or module-level applications.

[0062] A single resistor or PTC (positive temperature coefficient thermistor) primarily provides damping, limiting inrush current; PTCs also offer self-protection during overcurrent. A single inductor or RL series / parallel circuits, while providing damping, can form an LC resonant circuit with a high-frequency oscillating capacitor, enhancing energy transfer capabilities.

[0063] In some embodiments, the electrochemical energy storage device is a supercapacitor, an electrolytic capacitor, a lithium battery, a lithium-ion capacitor, a sodium-ion battery, a sodium-ion capacitor, or a lead-acid battery.

[0064] To make the objectives, technical solutions, and advantages of this invention clearer, the invention will be further described in detail below with reference to the accompanying drawings and specific embodiments. The following embodiments are for illustrative purposes only and do not constitute a limitation on the scope of protection of this invention.

[0065] Combined with appendix Figure 1 (Single System Composition Diagram) and Appendix Figure 2 (System Composition Block Diagram) The technical solution adopted in this invention is an oscillating adaptive energy transfer active balancing system based on RLC, wherein the system composition includes: system power supply, PWM signal generation circuit, synchronous drive circuit, n-1 high-frequency oscillation capacitors, n dual MOS push-pull level conversion circuits, n RL bidirectional oscillation damping circuits, and n electrochemical energy storage devices.

[0066] From the appendix Figure 1In a single system, each equalization unit (high-frequency oscillating capacitor, dual MOS push-pull level conversion circuit, and RL bidirectional oscillation damping circuit) targets an electrochemical energy storage device. The high-frequency oscillating capacitor, dual MOS push-pull level conversion circuit, and RL bidirectional oscillation damping circuit of each unit form a half-bridge resonant circuit. This half-bridge circuit operates continuously. Based on the device combination of the RL bidirectional oscillation damping circuit and the coordination with PWM signals of different frequencies and duty cycles, the entire unit half-bridge is kept in a high-frequency oscillating switching state. This high-frequency state effect, depending on the combination of device parameters and PWM frequency and duty cycle, can exhibit capacitive, resistive, inductive, or any comprehensive characteristic within the RLC triangular relationship. Simultaneously, the energy storage function of the high-frequency oscillating capacitor and energy storage inductor is utilized for energy transfer, along with the dynamic impedance effect of the comprehensive characteristics of the RLC network, continuously transferring energy from the high-voltage energy storage device to the low-voltage energy storage device, achieving the purpose of active energy transfer equalization.

[0067] Furthermore, because the half-bridge switches of each equalization unit operate in a same-frequency, same-phase switching manner, the voltage across the entire energy storage string, in relation to the individual cell voltage, exhibits an effect similar to the automatic horizontal flow of vibrating concrete mixers in the construction industry. (Appendix) Figure 1 (Single system block diagram) can also be understood as a series first-order oscillatory equilibrium system.

[0068] From the appendix Figure 2 It is understandable that in a paired system, each pair of electrochemical energy storage devices uses a connected device in series with an auxiliary device. Figure 1 This describes a half-bridge resonant active equalizer in phase, while another identical circuit is drawn from the center of this group to form another identical connection, operating at the same frequency in a two-way interleaved manner. (See attached...) Figure 2 It is mainly used in modules with multiple circular battery cells connected in series, which simplifies the module assembly structure and improves the equalization speed and reduces the equalization error under the same PWM conditions. (See attached image) Figure 2 (The block diagram of the group system) can also be understood as a parallel first-order oscillatory equilibrium system.

[0069] Attachment Figure 1 and attached Figure 2 When used in combination, they can form a series-parallel hybrid multi-stage oscillation equalization system. This multi-stage oscillation equalization system, when used with a PWM signal generation circuit that operates at the same frequency and has a controllable phase difference and duty cycle, can form a multi-stage vector active equalization. While possessing the advantages of the aforementioned multi-stage equalization, its overall equalization effect is a multi-stage phase vector sum, simultaneously considering the combined effects of frequency, phase, and amplitude. Therefore, this phase-shifting multi-stage combined oscillation equalization can be understood as a three-dimensional oscillation equalization system. In practical applications, the appropriate series-parallel connection method and order are selected based on various comprehensive requirements such as project scenario, cost, and technical specifications.

[0070] The above description is merely a preferred embodiment of the present invention and is intended to limit the present invention. 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 present invention.

Claims

1. An oscillating adaptive energy transfer active balancing system based on RLC, characterized in that, include: The system power supply is used to provide operating voltage to each unit of the system; A PWM signal generation circuit is used to generate PWM signal signals. A synchronous drive circuit, the input of which is connected to the output of the PWM signal generation circuit; n electrochemical energy storage devices connected in series, where n is an integer greater than or equal to 2; n RL bidirectional oscillation damping circuits, each of the RL bidirectional oscillation damping circuits being connected to a corresponding electrochemical energy storage device; n dual MOS push-pull level conversion circuits, the output of each dual MOS push-pull level conversion circuit is connected to a corresponding RL bidirectional oscillation damping circuit; n-1 high-frequency oscillation capacitors, each of which is connected between two adjacent dual MOS push-pull level conversion circuits; The n output terminals of the synchronous drive circuit are respectively connected to the control terminals of the n dual MOS push-pull level conversion circuits. The PWM signal generated by the PWM signal generation circuit drives all the dual MOS push-pull level conversion circuits to perform switching operations with the same frequency and phase through the synchronous drive circuit. This causes the high-frequency oscillation capacitor, the RL bidirectional oscillation damping circuit, and the electrochemical energy storage device to form an RLC oscillation network. The network's resonance and damping characteristics enable adaptive adjustment of the equalization current, thereby achieving energy transfer and voltage equalization among the series-connected electrochemical energy storage devices.

2. The system according to claim 1, characterized in that, The system power supply can be either internal energy storage self-powered or external power supply.

3. The system according to claim 1, characterized in that, The system power supply circuit is either a switching buck power supply or a linear regulated power supply.

4. The system according to claim 1, characterized in that, The PWM signal generation circuit includes a dedicated clock generation integrated circuit, an active crystal oscillator, a microcontroller, a digital signal processor, or a control unit of a battery management system.

5. The system according to claim 1, characterized in that, The synchronous drive circuit adopts non-isolated drive, optical isolation drive, magnetic isolation drive or charge isolation drive.

6. The system according to claim 1 or 5, characterized in that, The synchronous drive circuit adopts a cascaded expansion synchronous drive method.

7. The system according to claim 1, characterized in that, The high-frequency oscillation capacitor is a ceramic capacitor, tantalum capacitor, electrolytic capacitor, or film capacitor.

8. The system according to claim 1, characterized in that, The switching devices in the dual MOS push-pull level conversion circuit are MOS transistors, triodes, IGBTs, silicon carbide MOS transistors, or gallium nitride MOS transistors.

9. The system according to claim 1, characterized in that, The RL bidirectional oscillation damping circuit can be an RL series circuit, an RL parallel circuit, a single inductor, a single resistor, or a single positive temperature coefficient thermistor.

10. The system according to claim 1, characterized in that, The electrochemical energy storage device is a supercapacitor, electrolytic capacitor, lithium battery, lithium-ion capacitor, sodium-ion battery, sodium-ion capacitor, or lead-acid battery.

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