Metering-level high-power charging power supply

Abstract

The invention discloses a metering-level high-power charging power supply, and relates to the technical field of new energy, the metering-level high-power charging power supply comprises a main circuit and a feedback system, the main circuit comprises a rectification input link, an LLC isolation step-down link, a Buck pre-voltage-stabilizing link and a linear voltage-stabilizing link which are connected in sequence, and by arranging the Buck pre-voltage-stabilizing link and the linear voltage-stabilizing link, the voltage of the charging power supply can be adjusted. A Buck pre-voltage-stabilizing link is utilized to pre-stabilize voltage Vo2 output by a preceding-stage LLC isolation step-down link at a voltage level very close to output voltage Vo, it is ensured that the calorific value of a linear voltage-stabilizing tube Q6 is very small, and the precision of a charging power supply is improved by an order of magnitude by utilizing a linear voltage-stabilizing link. Therefore, two index requirements of high-power output and high-precision adjustment can be met at the same time.

Description

Technical Field

[0001] The present invention relates to the field of new energy technologies, and particularly to a metering-level high-power charging power supply. Background Art

[0002] With the global high emphasis on clean energy and sustainable development, the new energy industry is booming at an unprecedented speed. Against this background, as the core of new energy storage technologies, lithium batteries have been widely used in multiple fields such as electric vehicles, energy storage systems, and portable electronic devices due to their advantages such as high energy density, long cycle life, and environmental friendliness. However, with the continuous progress of lithium battery technologies and the increasing market demand, the accurate evaluation and metering of lithium battery performance have become one of the key factors restricting its further development.

[0003] Traditionally, the charging accuracy of lithium-ion charging power supplies is generally not high, mostly limited within an error range of 0.1%. Although this accuracy level can meet the daily charging needs to a certain extent, for high-precision measurement units, it obviously cannot meet their more stringent accuracy requirements, making it difficult to ensure the accuracy and reliability of data. Moreover, such products generally have the problem of insufficient power, and their output power is often limited to the level of a few watts, far from meeting the high-power requirements (usually several hundred watts or higher) during the metering process of large-capacity battery cells (such as 280 Ah and above). This contradiction not only restricts the application of high-precision metering technologies in the field of large-capacity lithium batteries but also hinders the process of lithium battery performance evaluation and optimization. Summary of the Invention

[0004] The purpose of the present invention is to provide a metering-level high-power charging power supply to solve the problems that the existing charging power supply has low charging accuracy, cannot meet more stringent accuracy requirements, and is difficult to ensure the accuracy and reliability of data.

[0005] A metering-level high-power charging power supply includes a main circuit and a feedback system. The main circuit includes a rectifier input section, an LLC isolation step-down section, a Buck pre-regulator section, and a linear voltage regulator section connected in sequence.

[0006] Preferably, the rectifier input section consists of four diodes D1, D2, D3, and D4 to form a bridge rectifier, which converts the voltage of the AC IN+ and AC IN- input ports of the alternating current into a direct current voltage Vo1.

[0007] Preferably, the LLC isolation step-down section forms an LLC resonant network through a resonant inductor Lr and a resonant capacitor Cr to generate a high-frequency alternating current on the primary side of the transformer TR, and the transformer TR transfers energy to the secondary side.

[0008] Preferably, the DC voltage Vo1 is controlled by two switching transistors Q1 and Q2, then flows through the LLC resonant network, and after being rectified by the diode D5, it is converted into a constant low DC voltage Vo2.

[0009] Preferably, the Buck pre-regulator is composed of a MOS transistor Q5, a freewheeling diode D9, an inductor L1, and a storage capacitor C3. The control method adopts a voltage hysteresis control with a fast response speed to convert the constant low DC voltage Vo2 into an arbitrarily adjustable DC voltage Vo3.

[0010] Preferably, the linear regulator is composed of a storage capacitor C4, a linear voltage regulator Q6, and current sampling resistors R1 and R2 to form a linear voltage regulator, which further smoothes the unstable DC voltage Vo3 provided by the previous Buck pre-regulator and adjusts and converts the DC voltage Vo3 into the output voltage Vo.

[0011] Preferably, the accuracy of the DC voltage Vo3 is 0.1%, and the accuracy of the output voltage Vo is 0.01%.

[0012] Preferably, the feedback system uses an operational amplifier to compare the output voltage Vo with the set voltage value Vset to generate a control voltage Vg6.

[0013] Preferably, in the feedback system, there is a drive voltage source dedicated to the gate signal generating device and its power supply arrangement required for MOSFETs or other power devices.

[0014] The advantages of the present invention are as follows: In the present invention, a metering-level high-power charging power supply, by setting two links of Buck pre-regulation and linear regulation, uses the Buck pre-regulation link to pre-stabilize the voltage Vo2 output by the previous LLC isolation step-down link at a voltage level very close to the output voltage Vo, ensuring that the heat generation of the linear voltage regulator Q6 is very small, and using the linear regulation link to improve the accuracy of the charging power supply by one order of magnitude, so that the two index requirements of high-power output and high-precision adjustment can be achieved simultaneously. The multi-stage conversion technology is adopted to realize the management strategy of the DC power supply process with high precision and good dynamic response from the power grid to the load, so as to ensure the accuracy and reliability of the data for evaluating and optimizing the performance of lithium batteries. BRIEF DESCRIPTION OF THE DRAWINGS

[0015] Figure 1 It is the circuit connection diagram of the present invention. DETAILED DESCRIPTION OF THE INVENTION

[0016] In order to make the technical means, creative features, achieved purposes, and effects of the present invention easy to understand, the present invention will be further described below in conjunction with specific embodiments.

[0017] Such as Figure 1As shown in the figure, a metering-level high-power charging power supply includes a main circuit and a feedback system. The main circuit includes a rectifier input section, an LLC isolation step-down section, a Buck pre-regulator section, and a linear voltage regulator section connected in sequence.

[0018] In this embodiment, the rectifier input section consists of four diodes D1, D2, D3, and D4 to form a bridge rectifier, which converts the voltage of the AC IN+ and AC IN- input ports of the alternating current into a DC voltage Vo1.

[0019] In this embodiment, the LLC isolation step-down section forms an LLC resonant network through a resonant inductor Lr and a resonant capacitor Cr, generates a high-frequency alternating current on the primary side of the transformer TR, and the transformer TR transfers energy to the secondary side.

[0020] In this embodiment, the DC voltage Vo1 is controlled by two switching transistors Q1 and Q2, then flows through the LLC resonant network, and after being rectified by the diode D5, it is converted into a constant DC low voltage Vo2.

[0021] In this embodiment, the Buck pre-regulator section consists of a MOS transistor Q5, a freewheeling diode D9, an inductor L1, and a storage capacitor C3. The control method uses a voltage hysteresis control with a fast response speed to convert the constant DC low voltage Vo2 into an arbitrarily adjustable DC voltage Vo3. The MOS transistor Q5 is set to adjust the output voltage Vo2 to achieve a stable intermediate voltage value.

[0022] In this embodiment, the linear voltage regulator section consists of a storage capacitor C4, a linear voltage regulator Q6, and current sampling resistors R1 and R2 to form a linear voltage regulator, which further smoothes the unstable DC voltage Vo3 provided by the previous Buck pre-regulator section and adjusts and converts the DC voltage Vo3 into an output voltage Vo. The accuracy of the DC voltage Vo3 is 0.1%, and the accuracy of the output voltage Vo is 0.01%.

[0023] In this embodiment, the feedback system uses an operational amplifier to compare the output voltage Vo with a set voltage value Vset to generate a control voltage Vg6.

[0024] In this embodiment, a drive voltage source dedicated to the gate signal generating device and its power supply arrangement required for MOSFETs or other power devices is provided in the feedback system, enabling the entire system to operate normally under appropriate bias conditions.

[0025] Working process and principle: When this device is in use, the input AC voltage is converted into a DC voltage Vo1 through the rectification input link, the DC voltage Vo1 is converted into a constant low DC voltage Vo2 through the LLC isolation step-down link, and then the constant low DC voltage Vo2 is converted into an arbitrarily adjustable DC voltage Vo3 by using the Buck pre-regulator link to achieve arbitrary adjustment of the output voltage. Then, the DC voltage Vo3 is adjusted and converted into the output voltage Vo through the linear voltage regulator link to achieve precise adjustment of the output voltage. The control combining Buck pre-regulation and precise adjustment of the linear power supply is adopted to meet the two index requirements of high-power output and high-precision adjustment simultaneously.

[0026] As is known by common technical knowledge, the present invention can be implemented by other embodiments that do not depart from its spiritual essence or essential features. Therefore, the above-disclosed embodiments are illustrative in all aspects and not exclusive. All changes within the scope of the present invention or within the scope equivalent to the present invention are encompassed by the present invention.

Claims

1. A metering-grade high-power charging power supply, characterized in that: It comprises a main circuit and a feedback system. The main circuit comprises a rectifier input link, an LLC isolation step-down link, a Buck pre-stabilization link and a linear voltage stabilization link which are connected in sequence.

2. A metering-grade high-power charging power supply according to claim 1, characterized in that: The rectifier input link is composed of four diodes D1, D2, D3 and D4 to form a bridge rectifier, which converts the voltage of the AC IN+ and AC IN- input ports of the alternating current into a direct current voltage Vo1.

3. A metering-grade high-power charging power supply according to claim 2, characterized in that: The LLC isolation and voltage reduction link forms an LLC resonant network through the resonant inductor Lr and the resonant capacitor Cr, generates a high-frequency alternating current on the primary side of the transformer TR, and the transformer TR transfers energy to the secondary side.

4. A metering-grade high-power charging power supply according to claim 3, characterized in that: The DC voltage Vo1 is controlled by two switching transistors Q1 and Q2, flows through the LLC resonant network, and is rectified by a diode D5 to be converted into a constant DC low voltage Vo2.

5. A metering-grade high-power charging power supply according to claim 4, characterized in that: The Buck pre-stabilization link is composed of a MOS tube Q5, a freewheeling diode D9, an inductor L1 and an energy storage capacitor C3. The control method adopts a voltage hysteresis control with a fast response speed to convert the constant DC low voltage Vo2 into an arbitrarily adjustable DC voltage Vo3.

6. A metering-grade high-power charging power supply according to claim 5, characterized in that: The linear voltage regulator link is composed of a storage capacitor C4, a linear voltage regulator Q6 and current sampling resistors R1 and R2 to form a linear voltage regulator, which further smoothes the unstable DC voltage Vo3 provided by the previous Buck pre-voltage regulator link and adjusts the DC voltage Vo3 to the output voltage Vo.

7. A metering-grade high-power charging power supply according to claim 7, characterized in that: The accuracy of the DC voltage Vo3 is 0.1%, and the accuracy of the output voltage Vo is 0.01%.

8. The metering-grade high-power charging power supply according to claim 1, characterized in that: The feedback system uses an operational amplifier to compare the output voltage Vo with the set voltage value Vset to generate a control voltage Vg6.

9. The metering-grade high-power charging power supply according to claim 1, characterized in that: The feedback system is provided with a gate signal generating device and a driving voltage source for power supply arrangement specifically for MOSFETs or other power devices.

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