Control method and device of DCDC system and vehicle

Abstract

The invention provides a control method and device of a DCDC system and a vehicle. The method comprises the steps that the output voltage of a charging pile and the working voltage of a high-voltage device are obtained; the charging voltage of the DCDC system is adjusted according to the output voltage and the working voltage, different types of charging piles and various power supply voltage ranges can be compatible, and the charging voltage is adjusted in real time until the working voltage is met.

Description

Technical Field

[0001] The present invention relates to the technical field of vehicles, and in particular, to a control method, a device, and a vehicle for a DCDC system. Background Art

[0002] With the rapid development of new energy vehicles, various vehicle voltage devices and different types of charging equipment have emerged, such as AC charging piles, DC charging piles, DC 200 - 500V, DC 300V - 750V, DC 300 - 1000V, etc. The diversity of high-voltage devices in the vehicle voltage platform makes it difficult for existing charging piles to match well with them. Summary of the Invention

[0003] The present invention aims to solve at least one of the technical problems existing in the prior art.

[0004] To this end, an object of the present invention is to provide a control method for a DCDC system, which can be compatible with different types of charging piles and a variety of power supply voltage ranges, and adjust the charging voltage in real time until the working voltage is satisfied.

[0005] To this end, a second object of the present invention is to provide a control device for a DCDC system.

[0006] To this end, a third object of the present invention is to provide a vehicle.

[0007] To achieve the above object, an embodiment of the first aspect of the present invention provides a control method for a DCDC system, the control method including: obtaining the output voltage of the charging pile and the working voltage of the high-voltage device; adjusting the charging voltage of the DCDC system according to the output voltage and the working voltage.

[0008] According to the control method of the DCDC system of the embodiment of the present invention, by obtaining the output voltage of the charging pile and the working voltage of the high-voltage device, determining the type of the output voltage, and adjusting the charging voltage of the DCDC control circuit according to the magnitude relationship between different types of output voltages and the working voltage, the present invention can be compatible with different types of charging piles and a variety of power supply voltage ranges, and adjust the charging voltage in real time until the working voltage is satisfied.

[0009] In some embodiments, the output voltage includes an AC voltage. Adjusting the charging voltage of the DCDC system according to the output voltage and the working voltage includes: rectifying and converting the AC voltage to determine a first DC voltage after rectification; adjusting the charging voltage to a first preset charging voltage according to the first DC voltage and the working voltage.

[0010] In some embodiments, adjusting the charging voltage to a first preset charging voltage according to the first DC voltage and the operating voltage includes: when the first DC voltage is greater than the operating voltage, reducing the charging voltage of the DCDC system until the first preset charging voltage is reached; when the first DC voltage is less than the operating voltage, increasing the charging voltage of the DCDC system until the first preset charging voltage is reached.

[0011] In some embodiments, after reaching the first preset charging voltage, it further includes: obtaining a first current threshold of the high-voltage device, a second current threshold of the DCDC control circuit, a third current threshold of the rectification module, and a fourth current threshold of the AC charging pile; determining the minimum value among the first current threshold, the second current threshold, the third current threshold, and the fourth current threshold as a first preset current; charging the high-voltage device according to the first preset current until the high-voltage device reaches a preset charge threshold.

[0012] In some embodiments, the output voltage includes a DC voltage range. Adjusting the charging voltage of the DCDC system according to the output voltage and the operating voltage includes: when the DC voltage range is greater than the operating voltage range, determining a second preset charging voltage of the DCDC system according to the DC voltage range.

[0013] In some embodiments, adjusting the charging voltage of the DCDC system according to the output voltage and the operating voltage further includes: when the DC voltage range is less than the operating voltage range, obtaining a second DC voltage; adjusting the charging voltage of the DCDC system to a second preset charging voltage according to the second DC voltage and the operating voltage.

[0014] In some embodiments, adjusting the charging voltage of the DCDC system to a second preset charging voltage according to the second DC voltage and the operating voltage includes: when the second DC voltage is greater than the operating voltage, reducing the charging voltage of the DCDC system until the second preset charging voltage is reached; when the second DC voltage is less than the operating voltage, increasing the charging voltage of the DCDC system until the second preset charging voltage is reached.

[0015] In some embodiments, after reaching the second preset charging voltage, it further includes: obtaining a fifth current threshold of the high-voltage device, a sixth current threshold of the DCDC control circuit, and a seventh current threshold of the DC charging pile; determining the minimum value among the fifth current threshold, the sixth current threshold, and the seventh current threshold as a second preset current; charging the high-voltage device according to the second preset current until the high-voltage device reaches a preset charge threshold.

[0016] To achieve the above object, an embodiment of the second aspect of the present invention provides a control device for a DCDC system, the control device comprising: an acquisition module configured to acquire the output voltage of a charging pile and the operating voltage of a high-voltage device; and an adjustment module configured to adjust the charging voltage of the DCDC system according to the output voltage and the operating voltage.

[0017] According to the control device of the DCDC system in the embodiment of the present invention, by acquiring the output voltage of the charging pile and the operating voltage of the high-voltage device, determining the type of the output voltage, and adjusting the charging voltage of the DCDC control circuit according to the magnitude relationship between different types of output voltages and the operating voltage, the present invention can be compatible with different types of charging piles and a variety of power supply voltage ranges, and adjust the charging voltage in real time until the operating voltage is satisfied.

[0018] To achieve the above object, an embodiment of the third aspect of the present invention provides a vehicle, the vehicle comprising the control device of the DCDC system in the above embodiment.

[0019] According to the vehicle in the embodiment of the present invention, by acquiring the output voltage of the charging pile and the operating voltage of the high-voltage device, determining the type of the output voltage, and adjusting the charging voltage of the DCDC control circuit 1 according to the magnitude relationship between different types of output voltages and the operating voltage, the present invention can be compatible with different types of charging piles and a variety of power supply voltage ranges, and adjust the charging voltage in real time until the operating voltage is satisfied.

[0020] The additional aspects and advantages of the present invention will be partially given in the following description, partially become apparent from the following description, or be understood through the practice of the present invention. BRIEF DESCRIPTION OF THE DRAWINGS

[0021] The above and / or additional aspects and advantages of the present invention will become apparent and be readily understood from the description of the embodiments in conjunction with the following drawings, in which: Figure 1 is a hardware connection diagram of a DCDC control system according to an embodiment of the present invention; Figure 2 is a flowchart of a control method for a DCDC system according to an embodiment of the present invention; Figure 3 is a flowchart of a control method for a DCDC system according to a specific embodiment of the present invention; Figure 4 is a structural block diagram of a control device for a DCDC system according to an embodiment of the present invention; Figure 5 is a structural block diagram of a vehicle according to an embodiment of the present invention.

[0022] Reference Signs: DCDC control system 100; DCDC control circuit 1; charging pile 2; high-voltage device 3; battery stack 4; AC charging pile 21; DC charging pile 22; Rectification module 11; DCDC buck-boost module 12; First switch K1, second switch K2, third switch K3, fourth switch K4, fifth switch K5; Fifth diode D5; sixth diode D6; seventh diode D7; eighth diode D8; ninth diode D9; tenth diode D10; Capacitor C1; First MOS transistor Q1; second MOS transistor Q2; third MOS transistor Q3; fourth MOS transistor Q4; First diode D1; second diode D2; third diode D3; fourth diode D4; Inductor L; Control device 200 of DCDC system; Acquisition module 201; adjustment module 202; Vehicle 300. Detailed implementation manners

[0023] The embodiments of the present invention will be described in detail below. The embodiments described with reference to the accompanying drawings are exemplary. The embodiments of the present invention will be described in detail below.

[0024] In recent years, the global energy crisis and environmental pollution have been intensifying continuously. The proton exchange membrane fuel cell (PEMFC) has been receiving more and more attention and research, and is considered to be the ultimate form of new energy for vehicles.

[0025] First, in combination with Figure 1 Describe the DCDC control system 100 of the embodiments of the present invention.

[0026] As Figure 1 shown, the DCDC control system 100 of the embodiments of the present invention includes: a charging pile 2, a high-voltage device 3, and a DCDC control circuit 1. Among them, The charging pile 2 is used to provide a power supply voltage; the high-voltage device 3 is used to consume the power supply voltage; the first end of the DCDC control circuit 1 is connected to the charging pile 2, and the second end of the DCDC control circuit 1 is connected to the high-voltage device 3, and is used to receive the power supply voltage output by the charging pile 2 and the working voltage of the high-voltage device 3, and output an adjustment signal of the DCDC control circuit 1 to adjust the charging voltage of the DCDC control circuit 1.

[0027] Specifically, the DCDC control circuit 1 includes an AC charging module and a DC charging module. Among them, the first end of the AC charging module is connected to the AC charging pile 21, the second end of the AC charging module is connected to the negative electrode of the high-voltage device 3, and the third end of the AC charging module is connected to the positive electrode of the high-voltage device 3. It is used to receive the AC voltage and working voltage output by the AC charging pile 21, output the AC adjustment signal of the DCDC control circuit 1, and adjust the charging voltage to the first preset charging voltage; the first end and the second end of the DC charging module are connected to the DC charging pile 22, the third end of the DC charging module is connected to the negative electrode of the high-voltage device 3, and the fourth end of the AC charging module is connected to the positive electrode of the high-voltage device 3. When the vehicle replenishes power to the high-voltage device 3, such as the power battery, through the DC charging pile 22, it is used to receive the DC voltage range and working voltage range output by the DC charging pile 22, output the DC adjustment signal of the DCDC control circuit 1, and adjust the charging voltage to the second preset charging voltage according to the DC adjustment signal.

[0028] The AC charging module includes a rectification module 11, an AC switch module, and a DCDC buck-boost module 12. Among them, the first end of the rectification module 11 is connected to the AC charging pile 21 and is used to receive the AC voltage and convert the AC voltage into the first DC voltage; the first end of the AC switch is connected to the third end of the rectification module 11, and the second end of the AC switch is connected to the second end of the rectification module 11. When receiving the first DC voltage, the AC switch module is closed to conduct the first path between the rectification module 11 and the high-voltage device 3; the first end of the DCDC buck-boost module 12 is connected to the third end of the AC switch module, the second end of the DCDC buck-boost module 12 is connected to the fourth end of the AC switch module, the third end of the DCDC buck-boost module 12 is connected to the negative electrode of the high-voltage device 3, and the fourth end of the DCDC buck-boost module 12 is connected to the positive electrode of the high-voltage device 3. When receiving the first AC adjustment signal, it controls the DCDC buck-boost module 12 to be in the buck mode to adjust the charging voltage to the first preset charging voltage, or when receiving the second AC adjustment signal, it controls the DCDC buck-boost module 12 to be in the boost mode to adjust the charging voltage to the first preset charging voltage.

[0029] The DC charging module includes a DC switch module and a DCDC buck-boost module 12. Among them, the first, second, and third ends of the DC switch module are connected to the DC charging pile 22, and the fourth end of the DC switch module is connected to the positive electrode of the high-voltage device 3, for conducting the second or third path between the DC charging pile 22 and the high-voltage device 3; the first end of the DCDC buck-boost module 12 is connected to the sixth end of the DC charging module, the second end of the DCDC buck-boost module 12 is connected to the seventh end of the DC charging module, the third end of the DCDC buck-boost module 12 is connected to the negative electrode of the high-voltage device 3, and the fourth end of the DCDC buck-boost module 12 is connected to the fifth end of the DC switch module and the negative electrode of the high-voltage device 3. When receiving the first DC adjustment signal, it controls the DCDC buck-boost module 12 to be in the buck mode to adjust the charging voltage to the second preset charging voltage, or when receiving the second DC adjustment signal, it controls the DCDC buck-boost module 12 to be in the boost mode to adjust the charging voltage to the second preset charging voltage.

[0030] The rectification module 11 includes: a fifth diode, denoted as D5 for example, a sixth diode, denoted as D6 for example, a seventh diode, denoted as D7 for example, an eighth diode, denoted as D8 for example, a ninth diode, denoted as D9 for example, a twelfth diode, denoted as D10 for example, and a capacitor, denoted as C1 for example. Among them, the positive electrode of the fifth diode D5 is connected to the first end of the AC switch module; the positive electrode of the sixth diode D6 is connected to the negative electrode of the fifth diode D5, and the negative electrode of the sixth diode D6 is connected to the second end of the AC switch module; the positive electrode of the seventh diode D7 is connected to the first end of the AC switch module; the positive electrode of the eighth diode D8 is connected to the negative electrode of the seventh diode D7, and the negative electrode of the eighth diode D8 is connected to the second end of the AC switch module; the positive electrode of the ninth diode D9 is connected to the first end of the AC switch module; the positive electrode of the twelfth diode D10 is connected to the negative electrode of the ninth diode D9, and the negative electrode of the twelfth diode D10 is connected to the second end of the AC switch module; one end of the capacitor C1 is connected to the first end of the AC switch module, and the other end of the capacitor C1 is connected to the second end of the AC switch module.

[0031] The AC switch module includes: a first switch, denoted as K1 for example, and a second switch, denoted as K2 for example. Among them, one end of the first switch K1 is connected to the second end of the rectification module 11, and the other end of the first switch K1 is connected to the first end of the DCDC buck-boost module 12; one end of the second switch K2 is connected to the third end of the rectification module 11, and the other end of the second switch K2 is connected to the second end of the DCDC buck-boost module 12. When receiving the first DC voltage, it closes the first switch K1 and the second switch K2 to conduct the first path between the rectification module 11 and the high-voltage device 3.

[0032] The DC switch module includes: a third switch, denoted as K3 for example, a fourth switch, denoted as K4 for example, and a fifth switch, denoted as K5 for example. Among them, one end of the third switch K3 is connected to the DC charging pile 22, and the other end of the third switch K3 is connected to the first end of the DCDC buck-boost module 12; one end of the fourth switch K4 is connected to the DC charging pile 22, and the other end of the fourth switch K4 is connected to the second end of the DCDC buck-boost module 12; the first end of the fifth switch K5 is connected to the DC charging pile 22, the second end of the fifth switch K5 is connected to the positive electrode of the high-voltage device 3, and the third end of the fifth switch K5 is connected to the fourth end of the DCDC buck-boost module 12. When receiving the first DC voltage range, the fourth switch K4 and the fifth switch K5 are closed to conduct the second path between the DC charging pile 22 and the high-voltage device 3, or when receiving the second DC voltage range, the third switch K3 and the fourth switch K4 are closed to conduct the third path between the DC charging pile 22 and the high-voltage device 3.

[0033] The DCDC buck-boost module 12 includes: a first MOS transistor, denoted as Q1 for example; a second MOS transistor, denoted as Q2 for example; a third MOS transistor, denoted as Q3 for example; a fourth MOS transistor, denoted as Q4 for example; a first diode, denoted as D1 for example; a second diode, denoted as D2 for example; a third diode, denoted as D3 for example; a fourth diode, denoted as D4 for example; and an inductor, denoted as L for example. Wherein, one end of the first MOS transistor Q1 is connected to the other end of the first switch K1 or the other end of the third switch K3; one end of the second MOS transistor Q2 is connected to the third end of the fifth switch K5 and the positive electrode of the high-voltage device 3; one end of the third MOS transistor Q3 is connected to the other end of the first MOS transistor Q1, and the other end of the third MOS transistor Q3 is connected to the other end of the fourth switch K4; one end of the fourth MOS transistor Q4 is connected to the other end of the second MOS transistor Q2, and the other end of the fourth MOS transistor Q4 is connected to the negative electrode of the high-voltage device 3; the positive electrode of the first diode D1 is connected to the other end of the first MOS transistor Q1, and the negative electrode of the first diode D1 is connected to one end of the first MOS transistor Q1; the positive electrode of the second diode D2 is connected to the other end of the second MOS transistor Q2, and the other end of the second diode D2 is connected to one end of the second MOS transistor Q2; the positive electrode of the third diode D3 is connected to the other end of the third MOS transistor Q3, and the other end of the third diode D3 is connected to one end of the third MOS transistor Q3; the positive electrode of the fourth diode D4 is connected to the other end of the fourth MOS transistor Q4, and the other end of the fourth diode D4 is connected to one end of the fourth MOS transistor Q4; one end of the inductor L is connected to the connection midpoint of the first MOS transistor Q1 and the third MOS transistor Q3, and the other end of the inductor L is connected to the connection midpoint of the second MOS transistor Q2 and the fourth MOS transistor Q4. When the DCDC buck-boost module 12 is in the buck mode, the second MOS transistor Q2 is closed, the fourth MOS transistor Q4 is turned off, and the on / off of the first MOS transistor Q1 and the third MOS transistor Q3 is controlled. Or when the DCDC buck-boost module 12 is in the boost mode, the first MOS transistor Q1 is closed, the third MOS transistor Q3 is turned off, and the on / off of the second MOS transistor Q2 and the fourth MOS transistor Q4 is controlled.

[0034] The DCDC control system 100 further includes: a battery stack 4, and the battery stack 4 is connected to the third end of the DCDC control circuit 1 for converting fuel chemical energy into electrical energy.

[0035] The following combines Figures 1-3 to describe the control method of the DCDC system according to the embodiments of the present invention.

[0036] As Figure 2 shown, the control method of the DCDC system according to the embodiments of the present invention at least includes step S1 and step S2.

[0037] Step S1, obtaining the output voltage of the charging pile and the working voltage of the high-voltage device.

[0038] In an embodiment, after the DCDC control circuit obtains the output voltage delivered by the charging pile and the operating voltage of the high-voltage device, denoted as V2 for example, it determines the source type of the output voltage, including the AC voltage output by the AC charging pile and the DC voltage output by the DC charging pile. By obtaining the output voltage of the charging pile, different types of charging piles and various power voltage ranges can be compatible.

[0039] Step S2: Adjust the charging voltage of the DCDC system according to the output voltage and the operating voltage.

[0040] In an embodiment, in the case of different types of output voltages, the magnitude relationship between the output voltage and the operating voltage is judged to determine whether the output voltage output by the charging pile meets the operating voltage required by the high-voltage device. If not, the charging voltage of the DCDC control circuit is adjusted in real time until the operating voltage that meets the high-voltage device is reached under different types.

[0041] According to the control method of the DCDC system according to the embodiment of the present invention, by obtaining the output voltage of the charging pile and the operating voltage of the high-voltage device, the type of the output voltage is judged, and the charging voltage of the DCDC control circuit is adjusted according to the magnitude relationship between different types of output voltages and the operating voltage. The present invention can be compatible with different types of charging piles and various power voltage ranges, and adjust the charging voltage in real time until the operating voltage is satisfied.

[0042] In some embodiments, the output voltage includes an AC voltage. Adjusting the charging voltage of the DCDC system according to the output voltage and the operating voltage includes: rectifying and converting the AC voltage to determine the first DC voltage after rectification; adjusting the charging voltage to a first preset charging voltage according to the first DC voltage and the operating voltage.

[0043] In an embodiment, when the vehicle replenishes power to the high-voltage device 3, such as the power battery, through the AC charging pile, the charging gun is connected, and low-voltage power is supplied to the battery monitoring and management system (BMS) of the vehicle, the DCDC control circuit 1, etc. After the connection information is confirmed to be correct, the AC voltage output by the AC charging pile is received. The rectification module 11 converts the AC voltage into a first DC voltage, denoted as V1 for example. The magnitude relationship between the first DC voltage V1 and the operating voltage V2 is judged to determine whether the first DC voltage V1 meets the operating voltage V2 required by the high-voltage device. If not, the charging voltage of the DCDC control circuit is adjusted in real time until the first preset charging voltage for AC charging is reached.

[0044] In some embodiments, adjusting the charging voltage to a first preset charging voltage according to the first DC voltage and the operating voltage includes: when the first DC voltage is greater than the operating voltage, reducing the charging voltage of the DCDC system until the first preset charging voltage is reached; when the first DC voltage is less than the operating voltage, increasing the charging voltage of the DCDC system until the first preset charging voltage is reached.

[0045] In an embodiment, if the first DC voltage is greater than the operating voltage, i.e., V1 > V2, the DCDC buck-boost module 12 is controlled to be in the buck mode to reduce the charging voltage until the first preset charging voltage is reached; if the first DC voltage is less than the operating voltage, i.e., V1 < V2, the DCDC buck-boost module 12 is controlled to be in the boost mode to increase the charging voltage until the first preset charging voltage is reached.

[0046] Wherein, when the DCDC buck-boost module 12 is in the buck mode, the DCDC control circuit 1 controls the second MOS transistor Q2 to be always on and the fourth MOS transistor Q4 to be always off, forming a BUCK buck structure. At the same time, the on-off of the first MOS transistor Q1 and the third MOS transistor Q3 is synchronously controlled by the pulse width modulation method, and there are two working cycles. One is that the first MOS transistor Q1 is closed and the third MOS transistor Q3 is open to charge the inductor L; the other is that the first MOS transistor Q1 is open and the third MOS transistor Q3 is closed, and the inductor L discharges to the load.

[0047] Or when the DCDC buck-boost module 12 is in the boost mode, the DCDC control circuit 1 controls the first MOS transistor Q1 to be always on and the third MOS transistor Q3 to be always off, forming a BUCK boost structure. At the same time, the on-off of the second MOS transistor Q2 and the fourth MOS transistor Q4 is synchronously controlled by the pulse width modulation method, and there are two working cycles. One is that the second MOS transistor Q2 is closed and the fourth MOS transistor Q4 is open to charge the inductor L; the other is that the second MOS transistor Q2 is open and the fourth MOS transistor Q4 is closed, and the inductor L discharges to the load.

[0048] In some embodiments, after reaching the first preset charging voltage, it further includes: obtaining a first current threshold of the high-voltage device, a second current threshold of the DCDC control circuit, a third current threshold of the rectification module, and a fourth current threshold of the AC charging pile; determining the minimum value among the first current threshold, the second current threshold, the third current threshold, and the fourth current threshold as the first preset current; charging the high-voltage device according to the first preset current until the high-voltage device reaches the preset charge threshold.

[0049] In an embodiment, after adjusting the charging voltage to the first preset charging voltage, the first current threshold I1 of the high-voltage device 3, the second current threshold I2 of the DCDC control circuit 1, the third current threshold I3 of the rectification module 11, and the fourth current threshold I4 of the AC charging pile 21 are received. The minimum current among the four currents, i.e., Imin (I1, I2, I3, I4), is determined as the first preset current, and the vehicle is charged according to the first preset current until the charging request current of the BMS is 0. At this time, the state of charge (SOC) is 100%, the charging ends, and the charging gun is disconnected.

[0050] In some embodiments, the output voltage includes a DC voltage range. Adjusting the charging voltage of the DCDC system according to the output voltage and the operating voltage includes: when the DC voltage range is greater than the operating voltage range, determining the second preset charging voltage of the DCDC system according to the DC voltage range.

[0051] In an embodiment, when the vehicle replenishes power to the high-voltage device 3, such as the power battery, through the DC charging pile, the charging gun is connected, and low-voltage power is supplied to the battery monitoring and management system of the vehicle and the DCDC control circuit 1, etc. After the connection information is confirmed to be correct, the DC voltage range output by the DC charging pile, such as denoted as V1~V2, is received. The coverage relationship between the DC voltage range V1~V2 and the operating voltage range V3~V4 is judged to determine whether the DC voltage range V1~V2 meets the operating voltage range V3~V4 required by the high-voltage device. If the DC voltage range V1~V2 can cover the operating voltage range V3~V4, it is considered that the DC charging pile 22 can directly charge the high-voltage device 3, such as the high-voltage battery. At this time, the second path between the DC charging pile 22 and the high-voltage device 3 is turned on, and the second preset charging voltage of the DCDC system is determined according to the DC voltage range, and the high-voltage device 3 is directly charged.

[0052] In some embodiments, adjusting the charging voltage of the DCDC system according to the output voltage and the operating voltage further includes: when the DC voltage range is less than the operating voltage range, obtaining a second DC voltage; adjusting the charging voltage of the DCDC system to the second preset charging voltage according to the second DC voltage and the operating voltage.

[0053] In an embodiment, if the DC voltage range V1~V2 cannot cover the operating voltage range V3~V4, it is considered that the DC charging pile 22 cannot directly charge the high-voltage device 3, such as the high-voltage battery. At this time, the third path between the DC charging pile 22 and the high-voltage device 3 is turned on, and the DCDC control circuit 1 obtains the second DC voltage V1 to judge the magnitude relationship between the second DC voltage V1 and the operating voltage V2, and determines whether the second DC voltage V1 meets the operating voltage V2 required by the high-voltage device. If not, the charging voltage of the DCDC control circuit is adjusted in real time until the second preset charging voltage for DC charging is reached.

[0054] In some embodiments, adjusting the charging voltage of the DCDC system to a second preset charging voltage according to the second DC voltage and the operating voltage includes: when the second DC voltage is greater than the operating voltage, reducing the charging voltage of the DCDC system until the second preset charging voltage is reached; when the second DC voltage is less than the operating voltage, increasing the charging voltage of the DCDC system until the second preset charging voltage is reached.

[0055] In an embodiment, the magnitude relationship between the second DC voltage V1 and the operating voltage V2 is judged. If the first DC voltage is greater than the operating voltage, i.e., V1 > V2, the DCDC buck-boost module 12 is controlled to be in the buck mode to reduce the charging voltage until the second preset charging voltage is reached; if the first DC voltage is less than the operating voltage, i.e., V1 < V2, the DCDC buck-boost module 12 is controlled to be in the boost mode to increase the charging voltage until the second preset charging voltage is reached.

[0056] In some embodiments, after reaching the second preset charging voltage, it further includes: obtaining the fifth current threshold of the high-voltage device, the sixth current threshold of the DCDC control circuit, and the seventh current threshold of the DC charging pile; determining the minimum value among the fifth current threshold, the sixth current threshold, and the seventh current threshold as the second preset current; charging the high-voltage device according to the second preset current until the high-voltage device reaches the preset charge threshold.

[0057] In an embodiment, after adjusting the charging voltage to the second preset charging voltage, the fifth current threshold I5 of the high-voltage device 3, the sixth current threshold I6 of the DCDC control circuit 1, and the seventh current threshold I7 of the DC charging pile 22 are received, and the minimum current among the three currents, i.e., Imin(I5, I6, I7), is determined as the second preset current. The vehicle is charged according to the second preset current until the charging request current of the BMS is 0. At this time, the state of charge is 100%, the charging is completed, and the charging gun is disconnected.

[0058] The following refers to Figure 3 to give an example of the control method of the DCDC system according to the embodiments of the present invention.

[0059] As Figure 3 shown, the control method of the DCDC system according to the embodiments of the present invention at least includes step S11-step S23.

[0060] Step S11, obtaining the output voltage of the charging pile and the operating voltage of the high-voltage device.

[0061] Step S12, rectifying and converting the AC voltage to determine the rectified first DC voltage.

[0062] Step S13, judging whether the first DC voltage is greater than the operating voltage. If so, execute step S14; otherwise, execute step S15.

[0063] Step S14, reduce the charging voltage of the DCDC system until the first preset charging voltage is reached.

[0064] Step S15, increase the charging voltage of the DCDC system until the first preset charging voltage is reached.

[0065] Step S16, obtain the first current threshold of the high-voltage device, the second current threshold of the DCDC control circuit, the third current threshold of the rectification module, and the fourth current threshold of the AC charging pile; determine the minimum value among the first current threshold, the second current threshold, the third current threshold, and the fourth current threshold as the first preset current; charge the high-voltage device according to the first preset current until the high-voltage device reaches the preset charge threshold.

[0066] Step S17, determine whether the DC voltage range is greater than the operating voltage range. If so, execute Step S19; otherwise, execute Step S18.

[0067] Step S18, obtain the second DC voltage.

[0068] Step S19, determine the second preset charging voltage of the DCDC system according to the DC voltage range.

[0069] Step S20, determine whether the second DC voltage is greater than the operating voltage. If so, execute Step S21; otherwise, execute Step S22.

[0070] Step S21, reduce the charging voltage of the DCDC system until the second preset charging voltage is reached.

[0071] Step S22, increase the charging voltage of the DCDC system until the second preset charging voltage is reached.

[0072] Step S23, obtain the fifth current threshold of the high-voltage device, the sixth current threshold of the DCDC control circuit, and the seventh current threshold of the DC charging pile; determine the minimum value among the fifth current threshold, the sixth current threshold, and the seventh current threshold as the second preset current; charge the high-voltage device according to the second preset current until the high-voltage device reaches the preset charge threshold.

[0073] According to the control method of the DCDC system in the embodiment of the present invention, by obtaining the output voltage of the charging pile and the operating voltage of the high-voltage device, judging the type of the output voltage, and adjusting the charging voltage of the DCDC control circuit according to the magnitude relationship between different types of output voltages and the operating voltage, the present invention can be compatible with different types of charging piles and a variety of power supply voltage ranges, and adjust the charging voltage in real time until the operating voltage is satisfied.

[0074] The following is combined with Figure 4Describe the control device 200 of the DCDC system according to an embodiment of the present invention.

[0075] As Figure 4 shown, the control device 200 of the DCDC system according to an embodiment of the present invention includes: an acquisition module 201 and an adjustment module 202, wherein, The acquisition module 201 is used to acquire the output voltage of the charging pile and the working voltage of the high-voltage device; the adjustment module 202 is used to adjust the charging voltage of the DCDC system according to the output voltage and the working voltage.

[0076] In an embodiment, after the acquisition module 201 of the DCDC control circuit acquires the output voltage delivered by the charging pile and the working voltage of the high-voltage device, for example, denoted as V2, it determines the source type of the output voltage, including the AC voltage output by the AC charging pile and the DC voltage output by the DC charging pile. By acquiring the output voltage of the charging pile, different types of charging piles and various power supply voltage ranges can be compatible.

[0077] The adjustment module 202 determines the magnitude relationship between the output voltage and the working voltage in the case of different types of output voltages, and determines whether the output voltage output by the charging pile meets the working voltage required by the high-voltage device. If not, it adjusts the charging voltage of the DCDC control circuit in real time until the working voltage that meets the high-voltage device is reached under different types.

[0078] According to the control device 200 of the DCDC system according to an embodiment of the present invention, by acquiring the output voltage of the charging pile and the working voltage of the high-voltage device, determining the type of the output voltage, and adjusting the charging voltage of the DCDC control circuit according to the magnitude relationship between different types of output voltages and the working voltage, the present invention can be compatible with different types of charging piles and various power supply voltage ranges, and adjust the charging voltage in real time until the working voltage is satisfied.

[0079] In some embodiments, when the output voltage includes an AC voltage, when the adjustment module 202 adjusts the charging voltage of the DCDC system according to the output voltage and the working voltage, it specifically is used for: rectifying and converting the AC voltage to determine the first DC voltage after rectification; adjusting the charging voltage to a first preset charging voltage according to the first DC voltage and the working voltage.

[0080] In some embodiments, when the adjustment module 202 adjusts the charging voltage to the first preset charging voltage according to the first DC voltage and the working voltage, it specifically is used for: when the first DC voltage is greater than the working voltage, reducing the charging voltage of the DCDC system until the first preset charging voltage is reached; when the first DC voltage is less than the working voltage, increasing the charging voltage of the DCDC system until the first preset charging voltage is reached.

[0081] In some embodiments, after the adjustment module 202 reaches the first preset charging voltage, it is further specifically configured to: obtain the first current threshold of the high-voltage device, the second current threshold of the DCDC control circuit, the third current threshold of the rectification module, and the fourth current threshold of the AC charging pile; determine the minimum value among the first current threshold, the second current threshold, the third current threshold, and the fourth current threshold as the first preset current; charge the high-voltage device according to the first preset current until the high-voltage device reaches the preset charge threshold.

[0082] In some embodiments, the output voltage includes a DC voltage range. When the adjustment module 202 adjusts the charging voltage of the DCDC system according to the output voltage and the operating voltage, it is specifically configured to: when the DC voltage range is greater than the operating voltage range, determine the second preset charging voltage of the DCDC system according to the DC voltage range.

[0083] In some embodiments, when the adjustment module 202 adjusts the charging voltage of the DCDC system according to the output voltage and the operating voltage, it is further specifically configured to: when the DC voltage range is less than the operating voltage range, obtain the second DC voltage; adjust the charging voltage of the DCDC system to the second preset charging voltage according to the second DC voltage and the operating voltage.

[0084] In some embodiments, when the adjustment module 202 adjusts the charging voltage of the DCDC system to the second preset charging voltage according to the second DC voltage and the operating voltage, it is specifically configured to: when the second DC voltage is greater than the operating voltage, reduce the charging voltage of the DCDC system until it reaches the second preset charging voltage; when the second DC voltage is less than the operating voltage, increase the charging voltage of the DCDC system until it reaches the second preset charging voltage.

[0085] In some embodiments, after the adjustment module 202 reaches the second preset charging voltage, it is further specifically configured to: obtain the fifth current threshold of the high-voltage device, the sixth current threshold of the DCDC control circuit, and the seventh current threshold of the DC charging pile; determine the minimum value among the fifth current threshold, the sixth current threshold, and the seventh current threshold as the second preset current; charge the high-voltage device according to the second preset current until the high-voltage device reaches the preset charge threshold.

[0086] According to the control device 200 of the DCDC system in the embodiments of the present invention, by obtaining the output voltage of the charging pile and the operating voltage of the high-voltage device, judging the type of the output voltage, and adjusting the charging voltage of the DCDC control circuit according to the magnitude relationship between different types of output voltages and operating voltages, the present invention can be compatible with different types of charging piles and various power supply voltage ranges, and adjust the charging voltage in real time until the operating voltage is satisfied.

[0087] The following combines Figure 5 to describe the vehicle 300 according to the embodiments of the present invention.

[0088] As shown Figure 5 in the figure, the vehicle 300 according to an embodiment of the present invention includes the control device 200 of the DCDC system in the above embodiment.

[0089] For the vehicle 300 according to an embodiment of the present invention, by obtaining the output voltage of the charging pile and the operating voltage of the high-voltage device, judging the type of the output voltage, and adjusting the charging voltage of the DCDC control circuit according to the magnitude relationship between different types of output voltages and operating voltages, the present invention can be compatible with different types of charging piles and a variety of power voltage ranges, and adjust the charging voltage in real time until the operating voltage is satisfied.

[0090] In the description of this specification, the description with reference to terms such as "one embodiment", "some embodiments", "schematic embodiments", "examples", "specific examples", or "some examples", etc. means that the specific features, structures, materials, or characteristics described in connection with the embodiment or example are included in at least one embodiment or example of the present invention. In this specification, the schematic representations of the above terms do not necessarily refer to the same embodiment or example.

[0091] Although the embodiments of the present invention have been shown and described, those of ordinary skill in the art can understand that various changes, modifications, substitutions, and variations can be made to these embodiments without departing from the principles and purposes of the present invention, and the scope of the present invention is defined by the claims and their equivalents.

Claims

1. A control method for a DCDC system, characterized in that: include: Obtain the output voltage of the charging pile and the operating voltage of the high-voltage device; The charging voltage of the DCDC system is adjusted according to the output voltage and the operating voltage.

2. The control method of the DCDC system according to claim 1, characterized in that: The output voltage includes an AC voltage, and adjusting the charging voltage of the DCDC system according to the output voltage and the working voltage includes: Rectifying and converting the AC voltage to determine a first rectified DC voltage; The charging voltage is adjusted to a first preset charging voltage according to the first DC voltage and the operating voltage.

3. The control method of the DCDC system according to claim 2, characterized in that: Adjusting the charging voltage to a first preset charging voltage according to the first DC voltage and the working voltage includes: When the first DC voltage is greater than the operating voltage, reducing the charging voltage of the DCDC system until it reaches a first preset charging voltage; When the first DC voltage is lower than the operating voltage, the charging voltage of the DCDC system is increased until it reaches the first preset charging voltage.

4. The control method of the DCDC system according to claim 3, characterized in that: After reaching the first preset charging voltage, the method further includes: Obtaining a first current threshold of the high-voltage device, a second current threshold of the DCDC control circuit, a third current threshold of the rectifier module, and a fourth current threshold of the AC charging pile; Determine that a minimum value among the first current threshold, the second current threshold, the third current threshold, and the fourth current threshold is a first preset current; The high-voltage device is charged according to the first preset current until the high-voltage device reaches a preset charge threshold.

5. The control method of the DCDC system according to claim 1, characterized in that: The output voltage includes a DC voltage range, and adjusting the charging voltage of the DCDC system according to the output voltage and the operating voltage includes: When the DC voltage range is greater than the operating voltage range, a second preset charging voltage of the DCDC system is determined according to the DC voltage range.

6. The control method of the DCDC system according to claim 5, characterized in that: The charging voltage of the DCDC system is adjusted according to the output voltage and the operating voltage, and further includes: When the DC voltage range is smaller than the operating voltage range, obtaining a second DC voltage; The charging voltage of the DCDC system is adjusted to a second preset charging voltage according to the second DC voltage and the operating voltage.

7. The control method of the DCDC system according to claim 6, characterized in that: Adjusting the charging voltage of the DCDC system to a second preset charging voltage according to the second DC voltage and the working voltage includes: When the second DC voltage is greater than the operating voltage, reducing the charging voltage of the DCDC system until it reaches a second preset charging voltage; When the second DC voltage is lower than the operating voltage, the charging voltage of the DCDC system is increased until it reaches a second preset charging voltage.

8. The control method of the DCDC system according to claim 7, characterized in that: After reaching the second preset charging voltage, the method further comprises: Obtaining a fifth current threshold of the high-voltage device, a sixth current threshold of the DCDC control circuit, and a seventh current threshold of the DC charging pile; Determine the fifth current threshold, the sixth current threshold, and the minimum value of the seventh current threshold is the second preset current; The high-voltage device is charged according to the second preset current until the high-voltage device reaches a preset charge threshold.

9. A control device for a DCDC system, characterized in that: include: An acquisition module is used to obtain the output voltage of the charging pile and the working voltage of the high-voltage device; The adjustment module is used to adjust the charging voltage of the DCDC system according to the output voltage and the operating voltage.

10. A vehicle, characterized in that: include: The control device of the DCDC system as claimed in claim 9.

Images