Multi-path and multi-direction PCB planar transformer wiring structure
Through the multi-channel and multi-directional PCB plane transformer wiring structure, semiconductor switch tubes are used to realize bidirectional transfer of battery voltage, solving the problems of complex transformer windings and inconsistent voltage in the prior art, and achieving rapid equalization of the battery pack and cost reduction.
Patent Information
- Application Number
- CN202422288610.8
- Authority / Receiving Office
- CN · China
- Patent Type
- Utility models(China)
- Current Assignee / Owner
- Filing Date
- 2024-09-19
- Publication Date
- 2025-08-22
- Estimated Expiration
- 2034-09-19
AI Technical Summary
In the existing lithium battery equalization technology, the multi-directional transformer windings are complex, difficult to produce, and high cost, and the battery voltage consistency cannot be achieved quickly and effectively, resulting in a shorter service life and increased cost of the battery pack.
The multi-channel and multi-directional PCB plane transformer wiring structure is adopted, including the main module, the secondary side module, the PCB and the MCU control circuit. The two-way power transfer between the battery cells is achieved through semiconductor switch tubes, and combined with DC/DC switching power supply technology, accurate and active equalization is achieved.
It achieves rapid consistency of battery cell voltage, simple structure, easy mass production, low cost, improves balanced efficiency, and reduces production and maintenance costs.
Smart Images
Figure CN223260416U_ABST
Abstract
Description
Technical Field
[0001] The utility model relates to the technical field of lithium batteries, in particular to a multi-path and multi-directional PCB planar transformer wiring structure. Background Art
[0002] With the rapid development of the new energy lithium battery industry, lithium batteries are increasingly widely used, and the requirements for their lifespan and cell voltage consistency are becoming increasingly stringent. However, as the number of batteries used in series increases, the battery capacity decays unevenly over time, causing voltage differences between cells. This voltage difference increases with age. The recycling and repair markets for retired automotive or power batteries urgently need auxiliary electronic devices that can fully and effectively utilize the value of recycled batteries, extend their lifecycle, and reduce operating costs, maintenance, and refurbishment costs. This can also reduce the complexity of production processes for pack production in both the secondary and primary markets.
[0003] Based on the above and other situations, the large voltage difference between battery cells will reduce the effective charge and discharge capacity of the entire battery pack. Therefore, an active balancing solution is needed to balance the battery cells. Currently, the most commonly used balancing methods in the industry include capacitor-based balancing, inductor-based balancing, and DC-DC balancing, each with its own advantages and disadvantages.
[0004] Existing active balancing technologies for lithium batteries include transformer winding (DCDC), which can achieve multi-directional balancing. This offers the highest efficiency, but the windings are twice as long as the balancing cells, resulting in a complex structure, difficult production, inconvenient maintenance, poor consistency, relatively high costs, and difficulty in market adoption. Another approach uses a relatively simple transformer structure, but can only charge or discharge one cell at a time, resulting in low efficiency and an inability to quickly and effectively balance the voltage of the entire battery pack. This results in unsatisfactory performance and a poor user experience. Furthermore, existing technologies generally use wound transformers, which have relatively poor inductance consistency. Utility Model Content
[0005] The purpose of the utility model is to provide a multi-path and multi-directional PCB planar transformer wiring structure, which solves the problems raised in the above technical background.
[0006] To achieve the above-mentioned purpose, the present invention provides the following technical solutions: a multi-channel and multi-directional PCB planar transformer wiring structure, comprising: a main module, a secondary module, a PCB and an MCU control circuit, wherein the main module comprises two main windings with the same number of turns and two power-supply switches, the same-name ends and the opposite-name ends of the two main windings are connected to each other, and the common end of the connection is electrically connected to the total voltage of the battery pack or the positive pole of the external power supply bus voltage, the other ends of the two main windings are respectively connected in series with a power-supply switch, and are electrically connected to the total voltage of the battery pack or the negative pole of the external power supply bus voltage through the power-supply switch, the secondary module comprises multiple A secondary winding, and the same number of balancing switches and battery cells as the secondary windings, wherein the multiple secondary windings include a number of odd-numbered windings and a number of even-numbered windings, the like-name ends of the odd-numbered windings are electrically connected to the positive poles of the corresponding number of battery cells, and the opposite-name ends are connected in series with a balancing switch and electrically connected to the negative poles of the corresponding number of battery cells, the opposite-name ends of the even-numbered windings are electrically connected to the positive poles of the corresponding number of battery cells, and the like-name ends are connected in series with another balancing switch and electrically connected to the negative poles of the corresponding number of battery cells, the like-name ends and the opposite-name ends of the main winding and the secondary winding are respectively connected to the PCB lead pins, and are electrically connected to the MCU control circuit through the PCB lead pins.
[0007] Preferably, the battery cell is electrically connected to a battery cell voltage acquisition circuit.
[0008] Preferably, the number of the secondary side modules is greater than or equal to 2.
[0009] Preferably, the ends with the same name of the odd-numbered windings are consistent with the ends with the same name of a main winding.
[0010] Preferably, the ends of the even-numbered windings with the same name are consistent with the ends of the other main winding with the same name.
[0011] Preferably, the power replenishment switch and the balancing switch are both semiconductor switch tubes.
[0012] Compared with the prior art, the beneficial effects of the present invention are as follows:
[0013] When the balancing conditions are met, through system control and the use of DC / DC switching power supply technology, bidirectional power transfer can be achieved between the total voltage of the battery pack or the system external power supply bus voltage and the battery cell. Bidirectional power transfer can also be achieved between battery cells. Therefore, accurate (one-time conversion) active balancing can be achieved for battery packs with voltage differences, quickly meeting the battery cell voltage consistency requirements.
[0014] This multi-channel and multi-directional PCB planar transformer wiring structure is an active balancing PCB planar transformer used in lithium battery packs. It has a simple structural design, good inductance consistency, is conducive to mass production, and has the advantages of high balancing efficiency and low cost. BRIEF DESCRIPTION OF THE DRAWINGS
[0015] Figure 1 This is the wiring schematic diagram of the utility model;
[0016] Figure 2 This is a wiring diagram of the utility model. DETAILED DESCRIPTION
[0017] The following will be combined with the drawings in the embodiments of the present invention to clearly and completely describe the technical solutions in the embodiments of the present invention. Obviously, the embodiments described are only part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without making creative efforts are within the scope of protection of the present invention.
[0018] Example 1
[0019] See also Figures 1 to 2 The present invention provides an embodiment of a multi-channel and multi-directional PCB planar transformer wiring structure, comprising: a main module, a secondary module, a PCB and an MCU control circuit, wherein the main module comprises two main windings with the same number of turns and two power-supply switches, the same-name end and the opposite-name end of the two main windings are connected to each other, and the common end of the connection is electrically connected to the total voltage of the battery pack or the positive pole of the external power supply bus voltage, the other end of the two main windings is respectively connected in series with a power-supply switch, and is electrically connected to the total voltage of the battery pack or the negative pole of the external power supply bus voltage through the power-supply switch, and the secondary module comprises multiple secondary windings with the same number of turns. , and the same number of balancing switches and battery cells as the secondary windings, the multiple secondary windings include 2 odd-numbered windings and 2 even-numbered windings, the like-name ends of the odd-numbered windings are electrically connected to the positive poles of the corresponding number of battery cells, and the opposite-name ends are connected in series with a balancing switch and electrically connected to the negative poles of the corresponding number of battery cells, the opposite-name ends of the even-numbered windings are electrically connected to the positive poles of the corresponding number of battery cells, and the like-name ends are connected in series with another balancing switch and electrically connected to the negative poles of the corresponding number of battery cells, the like-name ends and the opposite-name ends of the main winding and the secondary winding are respectively connected to the PCB lead pins, and are electrically connected to the MCU control circuit through the PCB lead pins;
[0020] This transformer TR adopts PCB planar transformer structure design. The main winding adopts two windings with the same number of turns. The same-name end of one winding (defined as main winding 1) and the opposite-name end of the other winding (defined as main winding 2) are connected together. The common end of the two main windings is connected to the total voltage of the battery pack or the positive pole of the external power supply bus voltage. The other end of the two main windings is connected in series with a semiconductor switch tube (the one connected to the main winding 1 is defined as SP1, and the one connected to the main winding 2 is defined as SP2) and connected to the total voltage of the battery pack or the negative pole of the external power supply bus voltage; the secondary winding adopts the same number of turns, two odd-numbered windings, and the same-name ends are connected to the positive pole of the external power supply bus voltage. Main winding 1 is consistent; for the two even-numbered windings, the same-named ends are consistent with main winding 2. At the same time, the same-named ends of the odd-numbered windings are connected to the positive pole of the corresponding string of cells, and the opposite-named ends are connected in series with a semiconductor switch tube and connected to the negative pole of the corresponding string of cells; the opposite-named ends of the even-numbered windings are connected to the positive pole of the corresponding string of cells, and the same-named ends are connected in series with a semiconductor switch tube and connected to the negative pole of the corresponding string of cells; according to the number of battery strings N+2 windings, the appropriate number of PCB layers is selected, and one winding is routed on one PCB layer. The same-named and opposite-named ends of the windings are connected to the PCB lead-out pins, which are made on the top and bottom layers respectively, and connected to the MCU control circuit control PCB in the form of pads;
[0021] Using PCB as the coil winding improves the consistency of transformer parameters such as parasitic capacitance compared to bobbin-wound copper wire, and also offers better electromagnetic performance and coupling. PCB coils offer a cost-effectiveness ratio and higher batch efficiency. PCB coils are highly scalable and can be made into one or several standard boards that can be used in any combination, offering flexibility and convenience. FUSEs can also be added to the PCB coil routing, making it safer than traditional coil winding methods and more compliant with safety certification requirements. This solves the problem of connecting PCB planar transformers to motherboards, eliminating the need for additional connectors and wiring harnesses and facilitating replacement. Using PCB boards in a similar gold finger-like manner, soldering and electrical connections ensures a balance between cost, maintainability, and connection reliability.
[0022] During specific use, the voltage of each string of cells in the battery pack is detected in real time through the cell voltage acquisition circuit. When the cell voltage difference is detected to reach the start-up condition, the MCU control circuit will balance the cells. The MCU control circuit controls the SP1 switch main winding 1 to realize the battery pack or external bus power supply voltage to supplement the odd-numbered strings of cells together, or only the balancing switch of the odd-numbered strings that need to be supplemented is turned on for balancing; the MCU control circuit controls the SP2 switch main winding 2 to realize the battery pack or external bus power supply voltage to supplement the even-numbered strings of cells together, or only the balancing switch of the even-numbered strings that need to be supplemented is turned on for balancing; the MCU control circuit controls the odd-numbered string SS (2n-1) switch to realize one of the odd-numbered strings to discharge the total voltage of the battery pack or the external power supply bus; the MCU controls the even-numbered string SS (2n) switch to realize one of the even-numbered strings to discharge the total voltage of the battery pack or the external power supply bus. By controlling the balancing switch on the secondary side through the MCU control circuit, any string can charge or discharge any other string (except the strings adjacent to the one with balancing turned on).
[0023] Example 2
[0024] See also Figures 1 to 2 The utility model proposes a multi-path and multi-directional PCB planar transformer wiring structure. Compared with the first embodiment, this embodiment also includes:
[0025] The battery cell is electrically connected to the battery cell voltage acquisition circuit; the battery cell voltage acquisition circuit performs real-time detection on the voltage of each string of battery cells in the battery pack. When the detected battery cell voltage difference reaches the condition for turning on the balancing circuit, the MCU control circuit controls the balancing circuit to balance the battery cells.
[0026] The number of the secondary modules is greater than or equal to 2; by making the secondary modules greater than or equal to 2, the odd-numbered windings and the even-numbered windings can be matched with the two main windings respectively, thereby achieving balance between the secondary modules.
[0027] The same-named ends of the odd-numbered windings are consistent with the same-named ends of a main winding; thereby the odd-numbered windings and the main winding are matched with each other, and the odd-numbered windings are balanced through the main winding.
[0028] The same-named ends of the even-numbered windings are consistent with the same-named ends of the other main winding; thereby the even-numbered windings and the other main winding are matched with each other, and the balancing of the even-numbered windings is completed through the other main winding.
[0029] The power replenishment switch and the balancing switch are both semiconductor switch tubes; the connectivity of the control circuit is achieved through the semiconductor switch tubes.
[0030] It will be apparent to those skilled in the art that the present invention is not limited to the details of the exemplary embodiments described above and that the present invention can be implemented in other specific forms without departing from the spirit or essential characteristics of the present invention. Therefore, the embodiments should be considered in all respects as illustrative and non-restrictive, and the scope of the present invention is defined by the appended claims, not the foregoing description, and all variations within the meaning and range of equivalents of the claims are intended to be encompassed within the present invention. Any reference sign in a claim should not be construed as limiting the claim to which it relates.
Claims
1. A multi-path and multi-directional PCB planar transformer wiring structure, characterized in that: include: The main module, the secondary module, the PCB and the MCU control circuit, the main module includes two main windings with the same number of turns, two power-supply switches, the same-name end and the opposite-name end of the two main windings are connected to each other, and the common end is electrically connected to the total voltage of the battery pack or the positive pole of the external power supply bus voltage. The other end of the two main windings is respectively connected in series with a power-supply switch, and is electrically connected to the total voltage of the battery pack or the negative pole of the external power supply bus voltage through the power-supply switch. The secondary module includes multiple secondary windings with the same number of turns, and the same number of balancing switches and power supplies as the secondary windings. Core, the multiple secondary windings include a number of odd-numbered windings and a number of even-numbered windings, the like-name ends of the odd-numbered windings are electrically connected to the positive poles of the corresponding number of battery cells in a string, and the opposite-name ends are connected in series with a balancing switch and electrically connected to the negative poles of the corresponding number of battery cells in a string, the opposite-name ends of the even-numbered windings are electrically connected to the positive poles of the corresponding number of battery cells in a string, and the like-name ends are connected in series with another balancing switch and electrically connected to the negative poles of the corresponding number of battery cells in a string, the like-name ends and the opposite-name ends of the main winding and the secondary winding are respectively connected to the PCB lead pins, and are electrically connected to the MCU control circuit through the PCB lead pins.
2. The multi-channel and multi-directional PCB planar transformer wiring structure according to claim 1, characterized in that: The battery cell is electrically connected to the battery cell voltage acquisition circuit.
3. The multi-path and multi-directional PCB planar transformer wiring structure according to claim 1, characterized in that: The number of the secondary side modules is greater than or equal to 2.
4. The multi-channel and multi-directional PCB planar transformer wiring structure according to claim 1, characterized in that: The ends with the same name of the odd-numbered windings are consistent with the ends with the same name of a main winding.
5. The multi-channel and multi-directional PCB planar transformer wiring structure according to claim 1, characterized in that: The ends of the even-numbered windings with the same name are consistent with the ends of the other main winding with the same name.
6. The multi-path and multi-directional PCB planar transformer wiring structure according to claim 1, characterized in that: The power replenishment switch and the balancing switch are both semiconductor switch tubes.