Supercharging system and control method thereof

Abstract

The application discloses an over-charge system and a control method thereof, and relates to the technical field of charging. The system comprises a multi-winding transformer, at least two charging modules and at least two charging interfaces, one end of each charging module is connected with a corresponding one of the secondary winding groups of the multi-winding transformer, and the other end is connected with at least one charging interface; the charging module comprises a first charging unit, M second charging units, a first switch unit and a second switch unit, one end of the first charging unit and each second charging unit is connected with a corresponding secondary winding group, the other end of the first charging unit is connected with each charging interface corresponding to the charging module through the first switch unit, and the other end of each second charging unit is connected with a corresponding charging interface of the charging module through a second switch unit respectively; wherein the first charging unit is a two-stage conversion topology, and the second charging unit is a single-stage conversion topology. Thus, the charging efficiency of the over-charge system is improved.

Description

Technical Field

[0001] This application relates to the field of charging technology, and in particular to a supercharging system and its control method. Background Technology

[0002] In the field of new energy charging technology, the power module in the charging system usually adopts a two-stage power conversion topology. However, in the two-stage power conversion topology, energy will accumulate losses after multiple conversions, resulting in low charging efficiency.

[0003] In charging scenarios for high-power vehicles such as heavy trucks and construction machinery, the charging system typically needs to support ultra-high voltage and ultra-high power charging requirements. Therefore, this two-stage power conversion topology is not suitable for ultra-high power applications. Summary of the Invention

[0004] The main objective of this application is to provide a supercharging system and its control method to improve the charging efficiency of the supercharging system.

[0005] To achieve the above objectives, this application provides a supercharging system, including a multi-winding transformer, at least two charging modules, and at least two charging interfaces. One end of each charging module is connected to a secondary winding of the multi-winding transformer, and the other end is connected to at least one of the charging interfaces.

[0006] The charging module includes a first charging unit, M second charging units, a first switching unit, and a second switching unit, where M ≥ 1 and is a positive integer. The first charging unit and each of the second charging units are connected in parallel. One end of the first charging unit and each of the second charging units is connected to the corresponding secondary winding. The other end of the first charging unit is connected to each charging interface of the charging module through the first switching unit. The other end of each of the second charging units is connected to a charging interface of the charging module through a second switching unit. The first charging unit is a two-stage transformation topology, and the second charging unit is a single-stage transformation topology.

[0007] Optionally, the first charging unit includes an AC / DC conversion circuit and a DC / DC conversion circuit, and the DC / DC conversion circuit is an isolated conversion circuit; the second charging unit includes at least one PCS conversion circuit, and the PCS conversion circuits are connected in parallel.

[0008] Optionally, the charging module further includes a control unit; the control unit is connected to the first charging unit and the first switching unit, and is used to control the opening or closing of the first charging unit and the first switching unit; the control unit is also connected to a corresponding second charging unit and a corresponding second switching unit, and is used to control the opening or closing of the corresponding second charging unit and the corresponding second switching unit.

[0009] Optionally, the charging module includes at least two second charging units and at least one second switching unit, and the charging module is connected to two charging interfaces respectively; wherein, a portion of the second charging units are connected to one charging interface through a second switching unit, and another portion of the second charging units are connected to the other charging interface through a second switching unit.

[0010] Optionally, the DC / DC converter circuit is an LLC topology or a BUCK-BOOST topology, and the PCS converter circuit is a T-shaped three-level topology, an I-shaped three-level topology, or a T-shaped two-level topology.

[0011] Furthermore, to achieve the above objectives, this application also provides a control method for a supercharging system, applied to the supercharging system as described in any of the preceding claims. The method includes: upon receiving a start charging command, controlling a first charging unit to start and using the first charging unit to perform a pre-detection of the supercharging system; and, if the supercharging system meets preset conditions, controlling the first charging unit and / or each of the second charging units to charge the load battery, wherein the preset conditions include the pre-detection result of the supercharging system being qualified.

[0012] Optionally, the pre-detection includes short-circuit detection. The step of controlling the first charging unit to start and using the first charging unit to perform pre-detection of the supercharging system includes: controlling the first charging unit to start and output a preset voltage, while the first switching unit and each of the second switching units remain in an open state; acquiring the output voltage of the first charging unit and performing short-circuit detection on the supercharging system based on the preset voltage and the output voltage; and, upon completion of the short-circuit detection, controlling the first charging unit to stop and discharging the voltage of the first charging unit.

[0013] Optionally, the pre-detection includes system insulation detection. The step of controlling the first charging unit to start and using the first charging unit to perform pre-detection of the supercharging system includes: controlling the first switching unit and each of the second switching units to be turned on; controlling the first charging unit to turn on and output a preset voltage, and performing system insulation detection of the supercharging system; and, upon completion of the system insulation detection, controlling the first charging unit to be turned off, discharging the voltage of the first charging unit, and controlling the first switching unit and each of the second switching units to be turned off.

[0014] Optionally, controlling the first charging unit and / or each of the second charging units to charge the load battery includes: controlling the first charging unit to start and output a preset start-up voltage, and controlling the first switching unit to turn on so that the first charging unit charges the load battery; controlling each of the second charging units to turn on and performing insulation detection on each of the second charging units, and, upon completion of the insulation detection, controlling each of the second charging units to stop and discharging the voltage of each of the second charging units; and controlling the first charging unit and / or each of the second charging units to charge the load battery according to a power distribution strategy.

[0015] Optionally, after performing a pre-detection of the supercharging system using the first charging unit, the method further includes: acquiring temperature data of the load battery; and if the temperature data is lower than a preset temperature, controlling the first charging unit to start and output a target current, the target current being used to heat the load battery.

[0016] The supercharging system of this application adds multiple second charging units with single-stage conversion topologies to the charging module. When performing a charging task, the first charging unit with two-stage conversion topologies and each of the second charging units can charge the load battery together, or only the second charging units can charge the load battery. Since the second charging unit is a single-stage conversion topology, the energy loss caused by the conversion is small, thus the charging efficiency is higher. In addition, before starting charging, the first charging unit with two-stage conversion topologies can be used to perform pre-detection of the supercharging system, ensuring the safety and reliability of the supercharging system. Attached Figure Description

[0017] Figure 1 This is one of the structural schematic diagrams of the supercharging system according to an embodiment of this application;

[0018] Figure 2 This is a schematic diagram of the structure of the first charging unit according to an embodiment of this application;

[0019] Figure 3 This is a circuit diagram of the first charging unit of an example of this application;

[0020] Figure 4 This is a schematic diagram of the structure of an example PCS conversion circuit of this application;

[0021] Figure 5 This is a second schematic diagram of the supercharging system according to an embodiment of this application;

[0022] Figure 6 This is the third schematic diagram of the supercharging system according to an embodiment of this application;

[0023] Figure 7 This is a schematic diagram of the structure of an example supercharging system of this application;

[0024] Figure 8 This is a flowchart of the control method of the supercharging system according to an embodiment of this application;

[0025] Figure 9 This is a control timing diagram of an embodiment of this application;

[0026] In the diagram, 100 is the charging module; 110 is the first charging unit; 120 is the second charging unit; 130 is the first switching unit; 140 is the second switching unit; 150 is the control unit; 160 is the display control unit; and 200 is the charging interface.

[0027] The realization of the purpose, functional features and advantages of this application will be further explained in conjunction with the embodiments and with reference to the accompanying drawings. Detailed Implementation

[0028] To make the objectives, technical solutions, and advantages of this application clearer, the technical solutions of this application will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some embodiments of this application, not all embodiments. Based on the embodiments of this application, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of this application.

[0029] In the field of new energy charging technology, especially for the charging needs of high-power vehicles such as heavy trucks and construction machinery, charging systems face the technical challenges of ultra-high voltage and high-power output. The currently prevalent two-stage power conversion architecture, while meeting basic functional requirements, exhibits significant efficiency bottlenecks in practical applications. In this traditional architecture, the front stage handles power factor correction and voltage regulation, while the rear stage uses an isolated converter to achieve electrical isolation and voltage matching. However, the accumulated losses from the two-stage energy conversion severely impact the overall efficiency of the charging system.

[0030] While single-stage power conversion topologies offer advantages in terms of structural simplicity and efficiency potential, they lack the capability for pre-charging system safety checks, such as insulation and short-circuit detection, because they can only output high power and large current. Furthermore, in special operating conditions like low temperatures, single-stage topologies struggle to output the small current required for battery preheating.

[0031] Therefore, current charging systems cannot balance safety and high efficiency, especially in ultra-high power applications, where this contradiction is even more pronounced, and innovative technical solutions are urgently needed to overcome existing limitations.

[0032] Therefore, this application provides a supercharging system and its control method. By combining a two-stage power conversion topology with a single-stage power conversion topology, in practical applications, the first charging unit of the two-stage power conversion topology is used to achieve insulation, short-circuit detection, and battery heating before charging. The second charging unit or the first charging unit of the single-stage conversion topology is then used to charge the load battery. This not only ensures the safety and reliability of the supercharging system's charging process but also effectively improves the charging efficiency of the supercharging system.

[0033] For ease of understanding, the system architecture of the supercharging system in this application embodiment will be described in detail below.

[0034] Figure 1 This is one of the structural schematic diagrams of the supercharging system according to an embodiment of this application. For example... Figure 1 As shown, the supercharging system may include a multi-winding transformer Tx, at least two charging modules 100 and at least two charging interfaces 200. One end of each charging module 100 is connected to a secondary winding of the multi-winding transformer Tx, and the other end is connected to at least one charging interface 200.

[0035] The charging module 100 includes a first charging unit 110, M second charging units 120, a first switching unit 130, and a second switching unit 140, where M ≥ 1 and is a positive integer. The first charging unit 110 and each of the second charging units 120 are connected in parallel. One end of the first charging unit 110 and each of the second charging units 120 is connected to the corresponding secondary winding. The other end of the first charging unit 110 is connected to each of the corresponding charging interfaces 200 of the charging module 100 through the first switching unit 130. The other end of each of the second charging units 120 is connected to a corresponding charging interface 200 of the charging module 100 through a second switching unit 140. The first charging unit 110 is a two-stage transformation topology, and the second charging unit 120 is a single-stage transformation topology.

[0036] First, it should be noted that the supercharging system of this application embodiment can be applied in electric vehicle charging scenarios, especially in charging scenarios for heavy trucks and mechanical engineering vehicles.

[0037] In this embodiment, the supercharging system may include a multi-winding transformer Tx, multiple charging modules 100, and multiple charging interfaces 200. The number of charging modules 100 and charging interfaces 200 can be set according to actual needs. For example, if the supercharging system of this embodiment is applied in a large charging station, a larger number of charging modules 100 and charging interfaces 200 can be set to meet the charging needs of the large charging station. The number of charging modules 100 and charging interfaces 200 is not specifically limited here.

[0038] Specifically, the multi-winding transformer Tx can be a power frequency transformer or a high-frequency transformer. This embodiment uses a multi-winding power frequency transformer as an example for subsequent description. The multi-winding transformer Tx can include one primary winding and several secondary windings. The primary winding is used to connect to a high-voltage power grid (e.g., 10kV high-voltage AC). The high-voltage power grid inputs three-phase AC power to the primary winding of the multi-winding transformer Tx, and the primary winding then distributes the electrical energy to the various secondary windings through magnetic coupling. In this embodiment, because the multi-winding transformer Tx is connected to three-phase power, the primary winding can consist of three windings, and these three windings can be connected using a delta connection or a star connection. Figure 1 The three sets of primary windings in the example use a delta connection.

[0039] Furthermore, in this embodiment, each secondary winding is connected to one charging module 100, meaning there is a one-to-one correspondence between the secondary winding and the charging module 100. The secondary winding is used to reduce the high voltage (e.g., 10kV AC) transmitted by the primary winding to the low voltage required by the charging module 100 (e.g., 480V or 690V low-voltage AC), and one secondary winding supplies power to one charging module 100 independently. In this embodiment, a secondary winding can also consist of three sets of windings, and the three sets of windings are connected in a star configuration. This is because the second charging unit 120 in this embodiment needs to connect not only the three phase lines A / B / C, but also the neutral line (N line) and the protective earth line (PE). The N line needs to be connected to the secondary winding; therefore, the secondary winding can only be connected in a star configuration. The specific connection methods of the second charging unit 120, the first charging unit 110, and the secondary winding can be found in [reference needed]. Figure 1 The connection methods in the document will not be elaborated here.

[0040] The multi-winding transformer Tx in this embodiment can realize voltage transformation from high voltage to low voltage, and also realize electrical isolation between the power grid and the supercharging system, electrical isolation between each charging module 100, and electrical isolation between charging terminals. For example, if the multi-winding transformer Tx is a power frequency transformer, then the multi-winding transformer Tx can realize voltage transformation from 10kV to 0.4kV. The rated capacity of one secondary winding of the multi-winding transformer Tx is 200kVA, which can be connected to a charging gun with a maximum supercharging power of 200kW.

[0041] In this embodiment, the supercharging system may include multiple charging interfaces 200, which are used to connect to a charging terminal (e.g., a charging gun) to charge the electric vehicle. Further, a charging module 100 may be connected to at least one charging interface 200. Different charging modules 100 are connected to different charging interfaces 200. All charging interfaces 200 connected to a charging module 100 can be referred to as the charging interface 200 corresponding to that module 100. The quantity relationship between the charging module 100 and the charging interfaces 200 connected to it can be set manually according to actual needs; therefore, the quantity relationship between the charging module 100 and the charging interface 200 is not specifically limited here.

[0042] As an example, if a charging module 100 is connected to one charging interface A, and charging interface A is connected to one charging gun 1, then the charging pile formed by the charging module 100 is a single-gun charging pile. If a charging module 100 is connected to both charging interface A and charging interface B, and charging interface A and charging interface B are connected to charging gun 1 and charging gun 2 respectively, then the charging pile formed by the charging module 100 is a dual-gun charging pile, and both charging interface A and charging interface B are charging interfaces 200 corresponding to the charging module 100.

[0043] In this embodiment, the charging module 100 is used to convert AC power from the power grid into DC power and provide it to the charging interface 200, and finally output it to the load battery through the charging terminal. The charging module 100 in this embodiment may include a first charging unit 110, M second charging units 120, a first switching unit 130 and a second switching unit 140, where M is a positive integer greater than or equal to 1.

[0044] Specifically, the first charging unit 110 is a two-stage power conversion topology, which can convert the AC power transmitted by the secondary winding into the required DC power. Furthermore, since the first charging unit 110 is a two-stage power conversion architecture, the two-stage power conversion architecture decouples the voltage through the front-stage conversion circuit and controls the current through the rear-stage conversion circuit, thereby enabling precise output of small current.

[0045] Furthermore, one end of the first charging unit 110 is connected to the corresponding secondary winding via a three-phase line, and the other end of the first charging unit 110 is connected to each charging port 200 of the charging module 100 via the first switching unit 130. As an example, if the charging module 100 is connected to three charging ports 200, then one end of the first switching unit 130 is connected to the first charging unit 110, and the other end of the first switching unit 130 is connected to all three charging ports 200.

[0046] The second charging unit 120 is a single-stage power conversion topology. The second charging unit 120 can also convert the AC power transmitted by the secondary winding into DC power. Furthermore, since the second charging unit 120 is a single-stage power conversion topology, its conversion efficiency is higher than that of the first charging unit 110. However, its power adjustment range is limited, and it cannot accurately output small currents.

[0047] Furthermore, one end of the second charging unit 120 is connected to the corresponding secondary winding via a four-phase wire, and the other end of the second charging unit 120 is connected to a corresponding charging interface 200 of the charging module 100 via a second switching unit 140. It should be noted that multiple second charging units 120 in the same charging module 100 can be connected to the corresponding charging interface 200 via the same second switching unit 140, and each second charging unit 120 in the same charging module 100 can also be connected to the corresponding charging interface 200 via different second switching units 140. As an example, if the charging module 100 is connected to charging interface A and charging interface B, and the charging module 100 includes a second charging unit A, a second charging unit B, a second switching unit A, and a second switching unit B, then the second charging unit A can be connected to charging interface A via the second switching unit A, and the second charging unit B can be connected to charging interface B via the second switching unit B. Other combinations can also be used, which are not listed here. As another example, if the charging module 100 is connected to charging interface A and charging interface B respectively, and the charging module 100 includes a second charging unit A, a second charging unit B and a second switch unit A, then the second charging unit A can be connected to the charging interface A through the second switch unit A, and the second charging unit B can also be connected to the charging interface B through the second switch unit A.

[0048] Therefore, by adding a second charging unit 120 with a single-stage power conversion topology to the charging module 100, when charging an electric vehicle is required, the first charging unit 110 can be controlled to output a small current before charging to achieve pre-charging safety monitoring and load battery heating of the supercharging system. When the detection is completed and charging begins, the first charging unit 110 and each of the second charging units 120 can be controlled to charge the electric vehicle simultaneously, or only each of the second charging units 120 can be controlled to charge the electric vehicle according to the charging demand, thereby effectively improving the charging efficiency and ensuring the safety and reliability of the supercharging system.

[0049] The components of the charging module 100 in this embodiment will be described in detail below.

[0050] In some embodiments, the first charging unit 110 includes an AC / DC conversion circuit and a DC / DC conversion circuit, and the DC / DC conversion circuit is an isolated conversion circuit; the second charging unit 120 includes at least one PCS conversion circuit, and the PCS conversion circuits are connected in parallel.

[0051] Figure 2 This is a schematic diagram of the structure of the first charging unit according to an embodiment of this application. Figure 2 As shown, the first charging unit 110 may include a front-end AC / DC conversion circuit and a rear-end DC / DC conversion circuit. The AC / DC conversion circuit and the DC / DC conversion circuit may be two circuit units in one module, or they may be two independent modules used together.

[0052] The AC / DC converter circuit is mainly used to rectify the input three-phase mains power into DC power, and then use a large-capacity electrolytic capacitor for voltage regulation and filtering before outputting the DC / DC converter circuit. The DC / DC converter circuit uses one or more LLC resonant cavities for output conversion, and uses a series and parallel combination of relays at the DC output terminal to achieve a wide range of output from low voltage 50V to high voltage 1000V.

[0053] In this embodiment, the AC / DC conversion circuit can be a non-isolated power conversion circuit. The AC / DC conversion circuit can adopt existing topologies, such as Vienna topology, single-level power supply topology, conventional two-level topology, three-level topology, etc. The specific topology of the AC / DC conversion circuit is not limited here. The DC / DC conversion circuit can be an isolated power conversion circuit. In some embodiments, the DC / DC conversion circuit can adopt LLC topology or BUCK-BOOST topology.

[0054] In addition, the first charging unit 110 may also include an input EMC module, an output rectifier module, and an output EMC module. The input EMC module is connected to the corresponding secondary coil and is used to ensure the stable operation of the first charging unit 110 in an electromagnetic environment, while reducing its interference with the power grid and other equipment, and preventing electromagnetic noise from the power grid from entering the first charging unit 110.

[0055] One end of the AC / DC converter circuit is connected to the input EMC module, and the other end is connected to the DC / DC converter circuit. The AC / DC converter circuit converts the AC power transmitted from the input EMC module into DC power. The DC power is then transmitted to the subsequent DC / DC converter circuit through the DC bus capacitor in the AC / DC converter circuit. The DC / DC converter circuit then performs further power conversion and outputs the required power.

[0056] One end of the output rectifier module is connected to the DC / DC converter circuit, and the other end is connected to the output EMC module. The output rectifier module is used to rectify the DC power output from the DC / DC converter circuit, while the output EMC module is used to suppress electromagnetic interference at the load end.

[0057] Figure 3 This is a circuit diagram of the first charging unit of an example of this application, which is shown below. Figure 3 Taking the first charging unit 110 shown in the figure as an example, the specific circuit structure of the first charging unit 110 is introduced.

[0058] like Figure 3 As shown, the AC / DC converter circuit uses the Vienna topology, while the DC / DC converter circuit uses the LLC topology. The AC / DC converter circuit can include an input unit, a rectification unit, and a DC output unit.

[0059] Specifically, the input unit may include a first switch Q1, a second switch Q2, a third switch Q3, a first inductor L1, a second inductor L2, and a third inductor L3. One end of the first switch Q1, the second switch Q2, and the third switch Q3 are respectively connected to the three-phase windings of the secondary winding; the other end of the first switch Q1, the second switch Q2, and the third switch Q3 are respectively connected to one end of the first inductor L1, the second inductor L2, and the third inductor L3.

[0060] The first switch Q1, the second switch Q2, and the third switch Q3 can be existing switches such as relays or transistors. When the first switch Q1, the second switch Q2, and the third switch Q3 are closed, the first charging unit 110 is turned on and started. The first inductor L1, the second inductor L2, and the third inductor L3 are used to limit the rate of current rise and help achieve power factor correction.

[0061] The rectifier unit may include a first diode D1, a second diode D2, a third diode D3, a fourth diode D4, a fifth diode D5, a sixth diode D6, a fourth switch Q4, a fifth switch Q5, a sixth switch Q6, a seventh switch Q7, an eighth switch Q8, and a ninth switch Q9.

[0062] The DC output unit may include a DC bus, on which a first electrolytic capacitor C1 and a second electrolytic capacitor C2 are connected in series; it may also include a tenth switch Q10, an eleventh switch Q11, a twelfth switch Q12 and a thirteenth switch Q13.

[0063] Specifically, the fourth switch Q4 and the fifth switch Q5 are connected in reverse series between the midpoint of the first inductor L1 and the DC bus, forming the first node N1 between the fourth switch Q4 and the first inductor L1. The sixth switch Q6 and the seventh switch Q7 are connected in reverse series between the midpoint of the second inductor L2 and the DC bus, forming the second node N2 between the sixth switch Q6 and the second inductor L2. The eighth switch Q8 and the ninth switch Q9 are connected in reverse series between the midpoint of the third inductor L3 and the DC bus, forming the third node N3 between the eighth switch Q8 and the third inductor L3.

[0064] It should be noted that the first electrolytic capacitor C1 and the second electrolytic capacitor C2 are connected in series, and the first electrolytic capacitor C1 and the second electrolytic capacitor C2 are set on the DC bus, with the midpoint of the DC bus between the first electrolytic capacitor C1 and the second electrolytic capacitor C2.

[0065] Furthermore, the anode of the first diode D1 is connected to the first node N1, and the cathode of the first diode D1 is connected to one end of the first electrolytic capacitor C1. The cathode of the second diode D2 is connected to the first node N1, and the anode of the second diode D2 is connected to one end of the second electrolytic capacitor C2. The anode of the third diode D3 is connected to the second node N2, and the cathode of the third diode D3 is connected to one end of the first electrolytic capacitor C1. The cathode of the fourth diode D4 is connected to the second node N2, and the anode of the fourth diode D4 is connected to one end of the second electrolytic capacitor C2. The anode of the fifth diode D5 is connected to the third node N3, and the cathode of the fifth diode D5 is connected to one end of the first electrolytic capacitor C1. The cathode of the sixth diode D6 is connected to the third node N3, and the anode of the sixth diode D6 is connected to one end of the second electrolytic capacitor C2.

[0066] The tenth switch Q10 and the eleventh switch Q11 are connected in series and then in parallel to the two ends of the DC bus, forming the fourth node N4 between them. Similarly, the twelfth switch Q12 and the thirteenth switch Q13 are connected in series and then in parallel to the two ends of the DC bus, forming the fifth node N5 between them.

[0067] It should be noted that the fourth switch Q4, the fifth switch Q5, the sixth switch Q6, the seventh switch Q7, the eighth switch Q8, the ninth switch Q9, the tenth switch Q10, the eleventh switch Q11, the twelfth switch Q12, and the thirteenth switch Q13 can be NMOS transistors, SiC MOS transistors, etc. Furthermore, the control terminals of the first switch Q1 to the thirteenth switch Q13 can be connected to the control unit 150 in subsequent embodiments, and the control unit 150 can control the closing or closing of each switch.

[0068] The DC / DC converter circuit may include a resonant unit, a rectifier unit, and an output protection unit. The resonant unit may include a third capacitor C3, a fourth inductor L4, and a first transformer T1; the rectifier unit may include a seventh diode D7, an eighth diode D8, a ninth diode D9, and a tenth diode D10; and the output protection unit includes a fourth capacitor C4 and an eleventh diode D11.

[0069] Specifically, one end of the third capacitor C3 is connected to the fifth node N5, and the other end of the third capacitor C3 is connected to one end of the primary winding of the first transformer T1. One end of the fourth inductor L4 is connected to the fourth node N4, and the other end of the fourth inductor L4 is connected to the other end of the primary winding of the first transformer T1. One end of the secondary winding of the first transformer T1 is connected to the anode of the seventh diode D7, and the other end of the secondary winding of the first transformer T1 is connected to the anode of the ninth diode D9.

[0070] The cathode of the seventh diode D7 is connected to the anode of the eleventh diode D11. The cathode of the eighth diode D8 is connected to the anode of the seventh diode D7. The anode of the eighth diode D8 is connected to the negative output terminal DC- of the DC / DC converter circuit. The cathode of the ninth diode D9 is connected to the anode of the eleventh diode D11. The cathode of the tenth diode D10 is connected to the anode of the ninth diode D9. The anode of the tenth diode D10 is connected to the negative output terminal DC- of the DC / DC converter circuit. One end of the fourth capacitor C4 is connected to the anode of the eleventh diode D11. The other end of the fourth capacitor C4 is connected to the negative output terminal DC- of the DC / DC converter circuit. The cathode of the eleventh diode D11 is connected to the positive output terminal DC+ of the DC / DC converter circuit.

[0071] In this embodiment, the third capacitor C3, the fourth inductor L4, and the first transformer T1 form a resonant circuit, which determines the operating frequency of the resonant unit. By selecting appropriate capacitor values, the resonant frequency can be adjusted to match the required switching frequency range. Furthermore, the third capacitor C3 helps stabilize the output voltage, reduces voltage fluctuations, and has a certain filtering effect. The fourth inductor L4 can store energy and release it when needed, and also helps control current peaks, protecting other components in the circuit from overcurrent damage. The main function of the first transformer T1 is to raise or lower the voltage to the required level. In addition, the first transformer T1 provides necessary electrical isolation to ensure the safety of the high-voltage and low-voltage sides.

[0072] In this embodiment, the second charging unit 120 may include at least one PCS conversion circuit. For example, the second charging unit 120 may include three PCS conversion circuits or two PCS conversion circuits. Each PCS conversion circuit can adopt the same topology. The number of PCS conversion circuits in the second charging unit 120 can be manually set by the operator according to actual needs. The specific number of PCS conversion circuits in the second charging unit 120 is not limited here. It should be noted that the PCS conversion circuit is also called an energy storage converter. The PCS conversion circuit is a non-isolated AC / DC power conversion circuit. The PCS conversion circuit can adopt existing T-shaped three-level circuits, I-shaped three-level circuits, and T-shaped two-level circuits, etc. The specific topology of the PCS conversion circuit is not limited here.

[0073] As an example, in a high-power charging scenario, a second charging unit 120 may include three sets of parallel PCS conversion circuits. If one set of PCS conversion circuits can output 65kW of power, then a second charging unit 120 can output 195kW of power. As another example, a second charging unit 120 may include two 125kW PCS conversion circuits, thus enabling a second charging unit 120 to output 250kW of power, achieving high-power charging.

[0074] Figure 4 This is a schematic diagram of an example PCS conversion circuit from this application. See below for reference. Figure 4 The example of a PCS conversion circuit is described in detail, along with a detailed explanation of its topology.

[0075] like Figure 4As shown, the PCS conversion circuit may include a fifth inductor L5, a sixth inductor L6, a seventh inductor L7, an eighth inductor L8, a fourteenth switch Q14, a fifteenth switch Q15, a sixteenth switch Q16, a seventeenth switch Q17, an eighteenth switch Q18, a nineteenth switch Q19, a twentieth switch Q20, a twenty-first switch Q21, a fifth capacitor C5, a twenty-second switch Q22, a twenty-third switch Q23, a twenty-fourth switch Q24, and a first resistor R1.

[0076] In this circuit, the fifth inductor L5, the sixth inductor L6, the seventh inductor L7, and the eighth inductor L8 are connected to a secondary winding of the multi-winding transformer Tx via the four phase lines A, B, C, and N, respectively. The fourteenth switch Q14 and the fifteenth switch Q15 are connected in series, with their two ends connected to the positive and negative output terminals of the PCS conversion circuit, respectively. The other end of the fifth inductor L5 is connected between the fourteenth and fifteenth switches Q14 and Q15. Similarly, the sixteenth switch Q16 and the seventeenth switch Q17 are connected in series, with their two ends connected to the positive and negative output terminals of the PCS conversion circuit, respectively. The other end of the sixth inductor L6 is connected between the sixteenth and seventeenth switches Q16 and Q17, respectively. Finally, the eighteenth switch Q18 and the nineteenth switch Q19 are connected in series, with their two ends connected to the positive and negative output terminals of the PCS conversion circuit, respectively. The other end of the seventh inductor L7 is connected between the eighteenth and nineteenth switches Q18 and Q19, respectively. After the twentieth switch Q20 and the twenty-first switch Q21 are connected in series, their two ends are connected to the positive output terminal and the negative output terminal of the PCS conversion circuit, respectively. The other end of the eighth inductor L8 is connected between the twentieth switch Q20 and the twenty-first switch Q21.

[0077] Furthermore, the fifth capacitor C5 is connected in parallel with the branch containing the twentieth switch Q20 and the twenty-first switch Q21. One end of the fifth capacitor C5 is connected to the positive output terminal of the PCS conversion circuit, and the other end is connected to the negative output terminal of the PCS conversion circuit. One end of the twenty-second switch Q22 is connected to one end of the fifth capacitor C5, and the other end of the twenty-second switch Q22 is connected to the positive output terminal of the PCS conversion circuit, forming the sixth node N6. One end of the twenty-third switch Q23 is connected to the fifth capacitor C5, and the other end of the twenty-third switch Q23 is connected to one end of the first resistor R1. The other end of the first resistor R1 is connected to the sixth node N6. One end of the twenty-fourth switch Q24 is connected to the other end of the fifth capacitor C5, and the other end of the twenty-fourth switch Q24 is connected to the negative output terminal of the PCS conversion circuit.

[0078] In this embodiment, the fourteenth switch Q14, the fifteenth switch Q15, the sixteenth switch Q16, the seventeenth switch Q17, the eighteenth switch Q18, the nineteenth switch Q19, the twentieth switch Q20, and the twenty-first switch Q21 can be NMOS transistors, SiC MOS transistors, etc.; the twenty-second switch Q22, the twenty-third switch Q23, and the twenty-fourth switch Q24 can be contactors or relays, etc.; and the control terminals of the fourteenth switch Q14 to the twenty-fourth switch Q24 can be connected to the control unit 150 in a subsequent embodiment, and the control unit 150 controls the closing or turning off of each switch. The fifth capacitor C5 can be a large-value electrolytic capacitor. It should also be noted that the twenty-second switch Q22 and the twenty-fourth switch Q24 are the main power switches of the PCS conversion circuit.

[0079] The above describes the specific structure of a PCS conversion circuit with an I-shaped three-level topology. The structures of the PCS conversion circuits in the second charging unit 120 can be the same or different.

[0080] Figure 5 This is the second structural schematic diagram of the supercharging system according to an embodiment of this application.

[0081] like Figure 5 As shown, in some embodiments, the first switch unit 130 may include a first controllable switch K1 and a second controllable switch K2, and the second switch unit 140 may include a third controllable switch K3 and a fourth controllable switch K4. One end of the first controllable switch K1 is connected to the positive output terminal of the first charging unit 110, and the other end of the first controllable switch K1 is connected to the positive input terminal of each corresponding charging interface 200; one end of the second controllable switch K2 is connected to the negative output terminal of the first charging unit 110, and the other end of the second controllable switch K2 is connected to the negative input terminal of each corresponding charging interface 200.

[0082] One end of the third controllable switch K3 is connected to the positive output terminal of the second charging unit 120, and the other end of the third controllable switch K3 is connected to the positive input terminal of the corresponding charging interface 200; one end of the fourth controllable switch K4 is connected to the negative output terminal of the second charging unit 120, and the other end of the fourth controllable switch K4 is connected to the negative input terminal of the corresponding charging interface 200.

[0083] It should be noted that the two controllable switches in each second switch unit 140 are uniformly referred to as the third controllable switch K3 and the fourth controllable switch K4; in addition, the first controllable switch K1, the second controllable switch K2, the third controllable switch K3 and the fourth controllable switch K4 can be selected from existing controllable switches such as relays and contactors, and no specific limitation is made on the above four controllable switches here.

[0084] In this embodiment, the first controllable switch K1 and the second controllable switch K2 are used to control the connection and disconnection of each charging interface 200 corresponding to the first charging unit 110 and the charging module 100; the third controllable switch K3 and the fourth controllable switch K4 are used to control the connection and disconnection of a charging interface 200 corresponding to the second charging unit 120 and the charging module 100.

[0085] Figure 6 This is the third structural schematic diagram of the supercharging system according to an embodiment of this application.

[0086] like Figure 6 As shown, in some embodiments, the charging module 100 further includes a control unit 150; the control unit 150 is connected to the first charging unit 110 and the first switching unit 130, and is used to control the opening or closing of the first charging unit 110 and the first switching unit 130; the control unit 150 is also connected to the corresponding second charging unit 120 and the corresponding second switching unit 140, and is used to control the opening or closing of the corresponding second charging unit 120 and the corresponding second switching unit 140.

[0087] Specifically, the charging module 100 may further include a control unit 150. The number of control units 150 may be less than or equal to the number of second charging units 120. For example, the number of control units 150 may be one, or the number of control units 150 may be equal to the number of second charging units 120. As an example, if the charging module 100 includes three second charging units 120, then the charging module 100 may include three control units 150, or it may include two control units 150. The control unit 150 may be a CCU monitoring board.

[0088] In this embodiment, the control unit 150 is mainly used to control the start-up or shutdown of each unit in the charging module 100. Taking the number of second charging units 120 being equal to the number of control units 150 as an example, specifically, one control unit 150 can be selected to control the first charging unit 110, the first switching unit 130, and one second charging unit 120 and one second switching unit 140; the remaining control units 150 can each individually control one second switching unit 140 and one second charging unit 120, that is, the second charging unit 120, the second switching unit 140 and the control unit 150 have a one-to-one correspondence. If the number of second charging units 120 is greater than the number of control units 150, then only some control units 150 need to control multiple second switching units 140 and second charging units 120, which will not be elaborated here.

[0089] In some embodiments, the charging module 100 may further include a display control unit 160, which may be an existing centralized control screen. The display control unit 160 can connect to the client of the charging APP or the charging platform via communication methods such as the Internet. The display control unit 160 can receive requests or information sent by the client or the charging platform and display this information to the user through the display screen. At the same time, the display control unit 160 can also send control commands to the control unit 150 in the charging module 100 based on the received requests.

[0090] It should be noted that the display control unit 160 can establish a communication connection with the corresponding control unit 150 through existing communication protocols.

[0091] Specifically, when a user needs to charge the vehicle, the user can initiate a charging request through the app. The app client then sends the charging request to the display control unit 160, which in turn sends a charging start control command to each control unit 150 based on the charging request. Alternatively, the user can also directly operate on the display screen of the display control unit 160 to initiate a charging request, which in turn sends a charging start control command to each control unit 150 based on the charging request.

[0092] In some implementations, multiple adjacent charging modules 100 may share a single display control unit 160. For example, two adjacent charging modules 100 may share a single display control unit 160, that is, the display control unit 160 controls the operation of the two charging modules 100.

[0093] Figure 7 This is a schematic diagram of an example supercharging system according to this application. The structure of the supercharging system will be further described below with a specific example.

[0094] like Figure 7 As shown, in some embodiments, the charging module 100 includes at least two second charging units 120 and at least one second switching unit 140, and the charging module 100 is correspondingly connected to two charging interfaces 200; wherein, a portion of the second charging units 120 are connected to one charging interface 200 through a second switching unit 140; and another portion of the second charging units 120 are connected to the other charging interface 200 through a second switching unit 140.

[0095] In this embodiment, a charging module 100 can be connected to two charging ports 200 to form a dual-gun charging device. The charging module 100 can charge the same electric vehicle through the two charging ports 200.

[0096] As an example, the charging module 100 may include two second charging units 120, two second switching units 140, two control units 150, and one display control unit 160, and the charging module 100 is correspondingly connected to two charging interfaces 200. The two second charging units 120 are respectively designated as second charging unit A and second charging unit B, the two second switching units 140 are respectively designated as second switching unit A and second switching unit B, the two control units 150 are respectively designated as control unit A and control unit B, and the two charging interfaces 200 are respectively designated as charging interface A and charging interface B.

[0097] Specifically, the first charging unit 110, the second charging unit A, and the second charging unit B are connected in parallel and one side is connected to a secondary winding of the multi-winding transformer Tx. The first charging unit 110 is connected to charging interface A and charging interface B respectively through the first switching unit 130. The second charging unit A is connected to charging interface A through the second switching unit A, and the second charging unit B is connected to charging interface B through the second switching unit B. Further, the control unit A can be used to control the first charging unit 110, the first switching unit 130, the second charging unit A, and the second switching unit A; the control unit B can be used to control the second charging unit B and the second switching unit B.

[0098] Charging port A and charging port B can each be connected to a charging gun. Users can choose to use both charging guns simultaneously or use each charging gun individually.

[0099] Furthermore, the charging module 100 may also include only one second switch unit 140, since both charging ports 200 charge the load battery simultaneously, and therefore can be controlled by a single second switch unit 140. That is, in the example above, the first charging unit 110 is connected to charging port A and charging port B respectively via the first switch unit 130; the second charging unit A is connected to charging port A via the second switch unit A, and the second charging unit B can also be connected to charging port B via the second switch unit A.

[0100] The above is an introduction to the structure of the supercharging system. Below, referring to the structure of the supercharging system, a detailed introduction to the control methods of the supercharging system will be provided.

[0101] Figure 8 This is a flowchart of the control method of the supercharging system according to an embodiment of this application. Figure 8 As shown, the control method of this supercharging system may include the following steps:

[0102] Step 810: Upon receiving a start charging command, control the first charging unit 110 to start and use the first charging unit 110 to perform a pre-detection of the supercharging system.

[0103] Step 820: When the supercharging system meets the preset conditions, control the first charging unit 110 and / or each of the second charging units 120 to charge the load battery, wherein the preset conditions include the supercharging system's pre-detection result being qualified.

[0104] First, it should be noted that the control method of this embodiment can be executed by the control unit 150 of the charging module 100 in the aforementioned embodiment, and each control unit 150 can execute the control method of the supercharging system.

[0105] Understandably, according to national charging standards, it is necessary to perform self-testing and insulation checks on the charging system before starting charging to ensure charging safety. However, while single-stage non-isolated PCS modules typically have extremely high efficiency, their topology limits their ability to achieve battery heating, short-circuit detection, and insulation checks with small currents. Therefore, this embodiment proposes a control method for starting a supercharging system, which not only enables short-circuit and insulation checks before charging but also significantly improves efficiency during the charging process.

[0106] The control method in this embodiment mainly involves controlling the first charging unit 110 to participate in battery heating, short circuit and insulation detection. After the detection and battery heating are completed, the second charging units 120 are controlled to charge the load battery, thereby realizing the self-test before charging of the supercharging system and improving the charging efficiency. Figure 9 This is a control timing diagram of an embodiment of this application, which is referred to below. Figure 9 The control logic for each stage of charging startup is described in detail.

[0107] Specifically, before charging is started, each unit in the charging module 100 is in standby mode, and the first controllable switch K1 and the second controllable switch K2 in the first switch unit 130 and the third controllable switch K3 and the fourth controllable switch K4 in each of the second switch units 140 are all in the off state, and each switch in the first charging unit 110 and the second charging unit 120 is also in the off state.

[0108] refer to Figure 9 At time T0, when the control unit 150 receives the start charging command issued by the display control unit 160, the control unit 150 can first control the first charging unit 110 to start, and perform the self-test process of the supercharging system by making the first charging unit 110 output voltage.

[0109] In some implementations, pre-detection may include short-circuit detection of the supercharging system. Step 810, which involves controlling the first charging unit 110 to start and using the first charging unit 110 to perform pre-detection of the supercharging system, may include: controlling the first charging unit 110 to start and output a preset voltage, while the first switching unit 130 and each of the second switching units 140 remain in an open state; acquiring the output voltage of the first charging unit 110 and performing short-circuit detection of the supercharging system based on the preset voltage and the output voltage; and, if the short-circuit detection is completed, controlling the first charging unit 110 to stop and discharging the voltage of the first charging unit 110.

[0110] Specifically, during times T0 to T1, when the control unit 150 receives the start charging command from the display control unit 160, the control unit 150 can first control the first charging unit 110 to turn on. This can be achieved by controlling the closing of each switch in the first charging unit 110. Simultaneously, a PID closed-loop control algorithm can be used to control the first charging unit 110 to output a preset voltage. It should be noted that the preset voltage can be the required output voltage of the load battery, which the control unit 150 can obtain from the electric vehicle's BMS (Battery Management System).

[0111] Furthermore, during the process of the first charging unit 110 outputting a preset voltage, the control unit 150 can collect the actual output voltage of the first charging unit 110. In this embodiment, the control unit 150 may be configured with a voltage and current sampling circuit, which can be used to sample the output voltage of the first charging unit 110; alternatively, a voltage sensor may be set at the first charging unit 110 and connected to the control unit 150, so that the voltage sensor can collect the output voltage of the first charging unit 110 and then output it to the control unit 150.

[0112] After the control unit 150 acquires the output voltage of the first charging unit 110, it can determine whether the first controllable switch K1 and the second controllable switch K2 in the first switching unit 130 are stuck together based on the output voltage and the preset voltage. If they are stuck together, it indicates that the charging module 100 is short-circuited; if they are not stuck together, it indicates that the charging module 100 is not short-circuited. The specific determination method can be implemented using existing short-circuit detection methods, which will not be elaborated here.

[0113] After completing the detection of the first switching unit 130, the control unit 150 can control the first charging unit 110 to stop. In this embodiment, a discharge circuit can also be provided in the charging module 100. The discharge circuit can be connected to the first charging unit 110 and each of the second charging units 120. The discharge circuit can be composed of multiple discharge resistors. The specific structure of the discharge circuit can refer to existing discharge circuits, which will not be described in detail here. At times T1~T2, that is, after controlling the first charging unit 110 to stop, the discharge circuit can be turned on to discharge the port voltage of the first charging unit 110 to below 60V, thereby ensuring the safety of the supercharging system.

[0114] In some embodiments, the pre-detection may include system insulation detection. Step 810, which controls the first charging unit 110 to start and uses the first charging unit 110 to perform pre-detection of the supercharging system, may also include: controlling the first switching unit 130 and each of the second switching units 140 to conduct; controlling the first charging unit 110 to turn on and output a preset voltage, and performing system insulation detection of the supercharging system; and, upon completion of the system insulation detection, controlling the first charging unit 110 to stop, discharging the voltage of the first charging unit 110, and controlling the first switching unit 130 and each of the second switching units 140 to turn off.

[0115] Specifically, during times T2 to T3, the control unit 150 can simultaneously close the first controllable switch K1, the second controllable switch K2, the third controllable switch K3, and the fourth controllable switch K4, and control the first charging unit 110 to start up. This can be achieved by controlling the closing of each switch transistor within the first charging unit 110. Simultaneously, the control unit 150 can output a preset voltage, which is the required output voltage of the load battery.

[0116] During times T3-T4, after the first charging unit 110 outputs a preset voltage, the control unit 150 can perform insulation detection between the supercharging system and the charging gun circuit to determine whether there are faults such as poor insulation or short circuits in the power circuit. Specific insulation detection methods can refer to existing methods and will not be elaborated here.

[0117] During times T4-T5, after the insulation test between the supercharging system and the charging gun circuit is completed, the control unit 150 can control the first charging unit 110 to shut down and use the discharge circuit to discharge the voltage at the port of the first charging unit 110. At the same time, the control unit 150 can control the first controllable switch K1, the second controllable switch K2, the third controllable switch K3, and the fourth controllable switch K4 to open simultaneously, thus completing the self-test process of the supercharging system.

[0118] In some embodiments, step 820, controlling the first charging unit 110 and / or each of the second charging units 120 to charge the load battery, may include: controlling the first charging unit 110 to start and output a preset start-up voltage, and controlling the first switching unit 130 to turn on so that the first charging unit 110 charges the load battery; controlling each of the second charging units 120 to turn on and performing insulation detection on each of the second charging units 120, and, upon completion of the insulation detection, controlling each of the second charging units 120 to stop and discharging the voltage of each of the second charging units 120; and controlling the first charging unit 110 and / or each of the second charging units 120 to charge the load battery according to a power distribution strategy.

[0119] After the supercharging system completes its self-test, the charging module 100 can begin charging the electric vehicle's load battery. The specific energy transfer process is as follows:

[0120] At time T6, the contactor on the vehicle side closes, connecting the vehicle side to the charging interface 200. The voltage of the vehicle-side load battery is fed back to the terminals of the first controllable switch K1, the second controllable switch K2, the third controllable switch K3, and the fourth controllable switch K4. That is, the voltages at the terminals of these switches are the same as the voltage of the load battery. The control unit 150 can collect the voltages at the terminals of these switches to obtain the current voltage of the load battery.

[0121] Furthermore, at times T6-T7, the control unit 150 can first control the first charging unit 110 to turn on and make the first charging unit 110 output a preset start-up voltage. It should be noted that the preset start-up voltage is lower than the current voltage of the load battery. The reason for the first charging unit 110 to output a voltage lower than the current voltage of the load battery is to reduce the voltage difference across the first switching unit 130 (i.e., the first controllable switch K1 and the second controllable switch K2), thereby ensuring that the first controllable switch K1 and the second controllable switch K2 can close normally, creating conditions for the first controllable switch K1 and the second controllable switch K2 to close.

[0122] At times T7-T8, after the first controllable switch K1 and the second controllable switch K2 are closed, the power circuit between the first charging unit 110 and the load battery is connected. The control unit 150 then increases the output voltage of the first charging unit 110, making its output voltage higher than that of the load battery, thereby causing the first charging unit 110 to output charging current to the load battery. Thus, the control unit 150 first controls the first charging unit 110 to pre-charge the load battery.

[0123] During times T8-T9, the control unit 150 can control the conduction of each PCS conversion circuit in the second charging unit 120, that is, control the closing of the main power switches (the twenty-second switch Q22 and the twenty-fourth switch Q24) in the PCS conversion circuit. At this time, the uncontrolled rectified voltage on the AC side is transmitted to the front end of the third controllable switch K3 and the fourth controllable switch K4. During times T9-T10, each parallel PCS conversion circuit performs ground insulation monitoring on the DC side to identify whether there are faults such as ground insulation abnormalities. The specific method of insulation detection for the second charging unit 120 can refer to the existing method of ground insulation detection for PCS conversion circuits, which will not be described in detail here.

[0124] Furthermore, at times T10-T11, after each PCS conversion circuit completes insulation testing, the control unit 150 can shut down the second charging unit 120 by controlling the 22nd switch Q22 and the 24th switch Q24 in the PCS conversion circuit to open. The control unit 150 further controls the discharge circuit to conduct, discharging the port voltage of the second charging unit 120 to below 60V. After the port voltage of the second charging unit 120 is discharged to below 60V, the control unit 150 controls the 3rd controllable switch K3 and the 4th controllable switch K4 to close, connecting the power circuit of the second charging unit 120 with the charging gun.

[0125] At times T11~T12, after the third controllable switch K3 and the fourth controllable switch K4 are closed, the voltage of the load battery will first charge the fifth capacitor C5 in the PCS conversion circuit through the DC side of the PCS conversion circuit. When the voltage of the fifth capacitor C5 is equal to the voltage of the load battery, the control unit 150 controls the twenty-second switch Q22 and the twenty-fourth switch Q24 to close, and controls the PCS conversion circuit to output a voltage higher than the voltage of the load battery, thereby enabling the second charging unit 120 to charge the load battery.

[0126] After the second charging unit 120 starts charging the load battery, the control unit 150 can use a power allocation algorithm and obtain a power allocation result based on parameters such as the load battery's required power, the maximum output power of the first charging unit 110, the maximum output power of the second charging unit 120, and the call priority. The control unit 150 can control the first charging unit 110 and / or each of the second charging units 120 to charge the load battery according to the power allocation result.

[0127] In this embodiment, the second charging unit 120 has a higher priority than the first charging unit 110. Therefore, during the power matching process, the second charging unit 120 is prioritized to charge the load battery. As an example, if the charging module 100 includes one 30kW first charging unit 110 and two 195kW second charging units 120, each second charging unit 120 includes three 65kW PCS conversion circuits, when the load battery's power requirement is greater than 390kW, the 30kW first charging unit 110 and each of the second charging units 120 can participate in the module call simultaneously; when the load battery's power requirement is less than or equal to 390kW, only any number of PCS conversion circuits from the two 195kW second charging units 120 need to be called. The power allocation algorithm used in this embodiment can be any existing power allocation algorithm; no specific limitation is made to the power allocation algorithm here.

[0128] When only the second charging unit 120 is used to charge the load battery, the first charging unit 110 can be turned off and the first controllable switch K1 and the second controllable switch K2 can be disconnected at times T12~T13. At the same time, the working mode of the second charging unit 120 can also be set, thereby improving the charging efficiency of the supercharging system.

[0129] In some implementations, when the required power or current is low, only the first charging unit 110 can be used to charge the load battery, and the second charging unit 120 can be turned off, because the second charging unit 120 is unlikely to output a small current.

[0130] During times T14-T15, when charging is complete and the control unit 150 receives a stop charging command from the BMS or display control unit 160, the control unit 150 controls the second charging unit 120 to shut down and stop outputting current. During times T15-T16, the control unit 150 can control the third controllable switch K3 and the fourth controllable switch K4 to open, and the contactor at the vehicle end will also open simultaneously. At this time, the charging power circuit is completely disconnected, the charging process ends, and all units in the charging module 100 enter standby mode.

[0131] In some embodiments, after performing a pre-detection of the supercharging system using the first charging unit 110, the control method further includes: acquiring temperature data of the load battery; and if the temperature data is lower than a preset temperature, controlling the first charging unit 110 to start and output a target current, the target current being used to heat the load battery.

[0132] Understandably, in practical applications, if the ambient temperature of the battery is relatively low, it needs to be heated first to improve battery activity. Heating the battery requires the charging module 100 to output a small current to achieve this.

[0133] Therefore, in this embodiment, after the pre-detection of the supercharging system is completed, the temperature data of the load battery can also be obtained. When the temperature data is lower than the preset temperature, the first charging unit 110 is controlled to turn on and output a target current, thereby heating the load battery using the target current. Specifically, the temperature data of the load battery can be provided to the control unit 150 by the BMS. The target current output by the first charging unit 110 can be manually set according to the current requirements of the vehicle, and no specific limitation is made to the target current here. After heating is completed, the subsequent charging process is executed.

[0134] Therefore, by adding a second charging unit 120 (i.e., PCS conversion circuit) to the charging module 100, the first charging unit 110 can be used to perform insulation and short circuit detection and battery heating before charging, and then the second charging unit 120 can be used to charge the load battery. The PCS conversion circuit not only has high charging efficiency but also lower cost, thereby effectively improving the charging efficiency of the supercharging system and reducing the cost of the supercharging system.

[0135] The device embodiments described above are merely illustrative. The units described as separate components may or may not be physically separate. The components shown as units may or may not be physical units; that is, they may be located in one place or distributed across multiple network units. Some or all of the modules can be selected to achieve the purpose of this embodiment according to actual needs. Those skilled in the art can understand and implement this without any creative effort.

[0136] Finally, it should be noted that the above embodiments are only used to illustrate the technical solutions of the present invention, and not to limit them; although the present invention 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; and these 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 the present invention.

Claims

1. A supercharging system, characterized in that, It includes a multi-winding transformer, at least two charging modules and at least two charging interfaces. One end of each charging module is connected to a secondary winding of the multi-winding transformer, and the other end is connected to at least one of the charging interfaces. The charging module includes a first charging unit, M second charging units, a first switching unit, and a second switching unit, where M ≥ 1 and is a positive integer. The first charging unit and each of the second charging units are connected in parallel. One end of the first charging unit and each of the second charging units is connected to the corresponding secondary winding. The other end of the first charging unit is connected to each charging interface of the charging module through the first switching unit. The other end of each of the second charging units is connected to a charging interface of the charging module through a second switching unit. The first charging unit is a two-stage transformation topology, and the second charging unit is a single-stage transformation topology.

2. The supercharging system according to claim 1, characterized in that, The first charging unit includes an AC / DC conversion circuit and a DC / DC conversion circuit, and the DC / DC conversion circuit is an isolated conversion circuit; The second charging unit includes at least one PCS conversion circuit, and the PCS conversion circuits are connected in parallel.

3. The supercharging system according to claim 1, characterized in that, The charging module also includes a control unit; The control unit is connected to the first charging unit and the first switching unit, and is used to control the opening or closing of the first charging unit and the first switching unit; The control unit is also connected to the corresponding second charging unit and the corresponding second switching unit, and is used to control the opening or closing of the corresponding second charging unit and the corresponding second switching unit.

4. The supercharging system according to claim 1, characterized in that, The charging module includes at least two second charging units and at least one second switching unit, and the charging module is connected to the two charging interfaces respectively. One portion of the second charging units is connected to one of the charging interfaces via a second switch unit, while another portion of the second charging units is connected to another charging interface via a second switch unit.

5. The supercharging system according to claim 2, characterized in that, The DC / DC converter circuit is an LLC topology or a BUCK-BOOST topology, and the PCS converter circuit is a T-shaped three-level topology, an I-shaped three-level topology, or a T-shaped two-level topology.

6. A control method for a supercharging system, characterized in that, Applied to the supercharging system as described in any one of claims 1 to 5, the method comprises: Upon receiving a charge start command, the system controls the first charging unit to start and uses the first charging unit to perform a pre-test of the supercharging system. When the supercharging system meets preset conditions, the first charging unit and / or each of the second charging units are controlled to charge the load battery, wherein the preset conditions include the supercharging system's pre-detection result being qualified.

7. The control method for the supercharging system according to claim 6, characterized in that, The pre-detection includes short-circuit detection. The control of the first charging unit to start and the use of the first charging unit to perform pre-detection of the supercharging system includes: The first charging unit is controlled to start and output a preset voltage, while the first switching unit and each of the second switching units remain in the off state. The output voltage of the first charging unit is collected, and the short circuit detection is performed on the supercharging system based on the preset voltage and the output voltage; Upon completion of the short-circuit detection, the first charging unit is shut down, and its voltage is discharged.

8. The control method for the supercharging system according to claim 6, characterized in that, The pre-detection includes system insulation detection. The control of the first charging unit to start and the use of the first charging unit to perform pre-detection of the supercharging system includes: Control the first switching unit and each of the second switching units to conduct; Control the first charging unit to turn on and output a preset voltage, and perform system insulation detection on the supercharging system; Upon completion of the system insulation test, the system controls the first charging unit to stop, discharges the voltage of the first charging unit, and controls the first switching unit and each of the second switching units to turn off.

9. The control method for the supercharging system according to claim 6, characterized in that, The control of the first charging unit and / or each of the second charging units to charge the load battery includes: The system controls the first charging unit to start and output a preset start-up voltage, and controls the first switching unit to turn on, so that the first charging unit charges the load battery. Control each of the second charging units to turn on, and perform insulation detection on each of the second charging units; and, upon completion of the insulation detection, control each of the second charging units to stop and discharge the voltage of each of the second charging units. The first charging unit and / or each of the second charging units are controlled to charge the load battery according to the power distribution strategy.

10. The control method for the supercharging system according to any one of claims 6 to 9, characterized in that, After performing a pre-detection of the supercharging system using the first charging unit, the method further includes: Obtain the temperature data of the load battery; If the temperature data is lower than the preset temperature, the first charging unit is controlled to start and output a target current, which is used to heat the load battery.

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