Charger control method, device, charger and vehicle

Abstract

The present disclosure relates to a charger control method, device, charger and vehicle. The method is applied to a charger, which is a vehicle-mounted charger or a charging pile charger, and the method includes: obtaining a first voltage of a battery; determining a target operating mode of an LLC circuit according to the first voltage, wherein the target operating mode is a full-bridge mode or a half-bridge mode; and controlling the LLC circuit to operate according to the target operating mode. Thus, the operating mode of the LLC circuit can be dynamically switched according to the battery voltage to avoid the generation of uncontrolled rectifier current, so that the charger can operate safely, stably and reliably in various operating conditions, and the control method is simple and efficient.

Description

Technical Field

[0001] The present disclosure relates to the field of vehicle technology, and in particular, to a charger control method, a charger, and a vehicle. Background Art

[0002] A charger is an electronic device that converts AC power into DC power. It is used as a charging device for electric vehicles to charge batteries. Existing chargers mostly use a two-stage topology, with a power factor correction circuit in the front stage and an isolated DCDC circuit (LLC (resonant circuit)) in the back stage. The bus capacitor is used to balance the instantaneous power difference between the AC side and the DC side.

[0003] At present, during the operation of the charger, the upper and lower bridge arms of each bridge arm of the isolated DCDC circuit are complementary to each other to realize the charging of the vehicle battery. However, when the AC side voltage of the charger is high and the battery voltage is low, an uncontrolled rectifier current will be generated, resulting in risks for the charger. Summary of the invention

[0004] In order to overcome the problems existing in the related art, the present disclosure provides a charger control method, a charger device, a charger and a vehicle.

[0005] In order to achieve the above-mentioned object, in a first aspect, the present disclosure provides a charger control method, which is applied to a charger, wherein the charger is a vehicle-mounted charger or a charging pile charger, and the charger includes an LLC circuit, and the LLC circuit is connected to a battery, and the method includes:

[0006] Acquiring a first voltage of the battery;

[0007] Determining a target operating mode of the LLC circuit according to the first voltage, wherein the target operating mode is a full-bridge mode or a half-bridge mode;

[0008] The LLC circuit is controlled to operate according to the target operating mode.

[0009] Optionally, determining a target operating mode of the LLC circuit according to the first voltage includes:

[0010] If the first voltage is less than a first preset voltage, determining that the target operating mode is the half-bridge mode;

[0011] If the first voltage is greater than or equal to the first preset voltage, the target operating mode is determined to be the full-bridge mode.

[0012] Optionally, the LLC circuit comprises an inverter circuit, a resonant circuit and a rectifier circuit connected in sequence, wherein the inverter circuit comprises a first phase bridge arm and a second phase bridge arm;

[0013] The controlling the LLC circuit to operate according to the target operating mode includes:

[0014] If the target operating mode is the half-bridge mode, the upper bridge arm and the lower bridge arm of the first phase bridge arm are controlled to be complementary turned on with a first duty cycle, and the upper bridge arm of the second phase bridge arm is controlled to be disconnected and the lower bridge arm is turned on;

[0015] If the target operating mode is the full-bridge mode, the upper bridge arm and the lower bridge arm of the first phase bridge arm are controlled to be complementary turned on with the first duty cycle, and the upper bridge arm and the lower bridge arm of the second phase bridge arm are controlled to be complementary turned on with the first duty cycle, wherein the upper bridge arm of the first phase bridge arm and the lower bridge arm of the second phase bridge arm are turned on at the same time, and the lower bridge arm of the first phase bridge arm and the upper bridge arm of the second phase bridge arm are turned on at the same time.

[0016] Optionally, the charger further includes a bus capacitor, a first bus terminal of the first phase bridge arm and the second phase bridge arm is connected to one end of the bus capacitor, and a second bus terminal of the first phase bridge arm and the second phase bridge arm is connected to the other end of the bus capacitor;

[0017] When the target operating mode is the full-bridge mode, before the step of controlling the upper bridge arm and the lower bridge arm of the first phase bridge arm to be complementarily turned on at the first duty cycle, controlling the LLC circuit to operate according to the target operating mode further includes:

[0018] Acquiring a second voltage of the bus capacitor;

[0019] If the second voltage is less than the second preset voltage, the step of controlling the upper bridge arm and the lower bridge arm of the first phase bridge arm to be complementary turned on with the first duty cycle is executed, wherein the ratio of the second preset voltage to the first preset voltage is equal to the turns ratio of the transformer in the resonant circuit.

[0020] Optionally, the controlling the LLC circuit to operate according to the target operating mode further includes:

[0021] If the second voltage is greater than or equal to the second preset voltage, the upper bridge arm and the lower bridge arm of the first phase bridge arm are controlled to be turned on complementarily with the second duty cycle, and the upper bridge arm and the lower bridge arm of the second phase bridge arm are controlled to be turned on complementarily with the second duty cycle, wherein the upper bridge arm of the first phase bridge arm and the lower bridge arm of the second phase bridge arm are turned on at the same time, the lower bridge arm of the first phase bridge arm and the upper bridge arm of the second phase bridge arm are turned on at the same time, and the second duty cycle is less than the first duty cycle.

[0022] Optionally, the charger further comprises a power factor correction circuit and a bus capacitor, wherein the power factor correction circuit is connected to the LLC circuit via the bus capacitor;

[0023] The method further comprises:

[0024] Acquire current power information of the AC side of the charger and the second voltage of the bus capacitor, wherein the power information includes the current current and the current voltage of the AC side;

[0025] determining a steady-state target current of the AC side;

[0026] Determining a target current value of the AC side according to the current voltage and the steady-state target current;

[0027] The power factor correction circuit is controlled to perform power factor correction according to the target current value, the current current, the current voltage and the second voltage.

[0028] Optionally, determining the steady-state target current of the AC side includes:

[0029] Determining a target charging power on the AC side;

[0030] The steady-state target current of the AC side is determined according to the target charging power.

[0031] In a second aspect, the present disclosure provides a charger control device, comprising:

[0032] a memory having a computer program stored thereon;

[0033] A controller, wherein when the computer program is executed by the controller, the steps of the charger control method provided in the first aspect of the present disclosure are implemented.

[0034] In a third aspect, the present disclosure provides a charger, including a power factor correction circuit, a bus capacitor, and an LLC circuit connected in sequence, and the charger further includes:

[0035] The charger control device provided in the second aspect of the present disclosure is connected to the power factor correction circuit and the LLC circuit respectively.

[0036] In a fourth aspect, the present disclosure provides a vehicle, comprising a battery and the charger provided in the third aspect of the present disclosure.

[0037] In the above technical solution, the target working mode of the LLC circuit can be determined according to the battery voltage, and then the LLC circuit can be controlled to work according to the target working mode. Among them, the target working mode is full-bridge mode or half-bridge mode, so that the working mode of the LLC circuit can be dynamically switched according to the battery voltage to avoid the generation of uncontrolled rectifier current, so that the charger can work safely, stably and reliably in various working conditions, and the control method is simple and efficient.

[0038] Other features and advantages of the present disclosure will be described in detail in the following detailed description. BRIEF DESCRIPTION OF THE DRAWINGS

[0039] The accompanying drawings are used to provide a further understanding of the present disclosure and constitute a part of the specification. Together with the following specific embodiments, they are used to explain the present disclosure but do not constitute a limitation of the present disclosure. In the accompanying drawings:

[0040] Figure 1 The figure is a structural block diagram of a charger according to an exemplary embodiment.

[0041] Figure 2 The figure is a circuit topology diagram of a charger according to an exemplary embodiment.

[0042] Figure 3 The figure is a flow chart of a charger control method according to an exemplary embodiment.

[0043] Figure 4 The invention is a schematic diagram showing a control method of a power factor correction circuit in a charger according to an exemplary embodiment. DETAILED DESCRIPTION

[0044] The specific implementation of the present disclosure is described in detail below in conjunction with the accompanying drawings. It should be understood that the specific implementation described herein is only used to illustrate and explain the present disclosure, and is not used to limit the present disclosure.

[0045] The present disclosure provides a charger, wherein the charger can be a vehicle-mounted charger or a charging pile charger, and the charging pile charger can adopt the same circuit topology as the vehicle-mounted charger (such as Figure 2 As shown in Figure 1 As shown, the charger 100 includes a charger control device 5, and a power factor correction circuit 2, a bus capacitor C1, and an LLC circuit 3 connected in sequence, wherein the power factor correction circuit 2 is connected to the power grid 1, the LLC circuit 3 is used to connect to the battery 4, and the bus capacitor C1 can be an electrolytic capacitor, a film capacitor, a ceramic capacitor, etc., for DC voltage filtering.

[0046] The charger control device 5 is connected to the power factor correction circuit 2 and the LLC circuit 3 respectively, and is used to execute the charging control method applied to the above charger to control the power factor correction circuit 2 and the LLC circuit 3 to work, thereby realizing battery charging. Among them, the power factor correction circuit 2 is used to perform power factor correction on the input signal of the power grid and output the current signal after power factor correction; the LLC circuit 3 is used to perform DC conversion on the current signal after power factor correction to obtain DC power to charge the battery of the vehicle.

[0047] like Figure 2 As shown, the power factor correction circuit 2 may include: a third phase bridge arm composed of a first switch tube T1 and a second switch tube T2, and a fourth phase bridge arm composed of a third switch tube T3 and a fourth switch tube T4, wherein the midpoint of the third phase bridge arm is connected to the positive electrode of the power grid 1 through the inductor L1, and the midpoint of the fourth phase bridge arm is connected to the negative electrode of the power grid 1; the third bus terminals of the third phase bridge arm and the fourth phase bridge arm are connected to one end of the bus capacitor C1, and the fourth bus terminals of the third phase bridge arm and the fourth phase bridge arm are connected to the other end of the bus capacitor C1.

[0048] Among them, the current voltage on the AC side of the charger is u a , the current on the AC side of the charger is i a , the voltage across the bus capacitor C1 is Ubus (ie, the second voltage).

[0049] like Figure 2 As shown, the LLC circuit 3 includes an inverter circuit 31, a resonant circuit 32 and a rectifier circuit 33 which are connected in sequence.

[0050] Among them, the inverter circuit 31 includes: a first phase bridge arm composed of a fifth switch tube T5 and a sixth switch tube T6, and a second phase bridge arm composed of a seventh switch tube T7 and an eighth switch tube T8, the first bus ends of the first phase bridge arm and the second phase bridge arm are respectively connected to one end of the bus capacitor C1 and the above-mentioned third bus end, and the second bus ends of the first phase bridge arm and the second phase bridge arm are respectively connected to the other end of the bus capacitor C1 and the above-mentioned fourth bus end.

[0051] The resonant circuit 32 adopts an LLC type resonant cavity, including a resonant inductor L2, a resonant capacitor C2 and a transformer M1. Among them, the resonant inductor L2 has one end connected to the midpoint of the first phase bridge arm, and the other end connected to the first input end of the primary side of the transformer M1, wherein the resonant inductor L2 can be magnetically integrated with the transformer M1 and participate in the resonance in the resonant circuit; the resonant capacitor C2 has one end connected to the midpoint of the second phase bridge arm, and the other end connected to the second input end of the primary side of the transformer M1, and the resonant capacitor C2 can be selected from a film capacitor or a ceramic capacitor to prevent the transformer M1 from having a DC bias and participating in the resonance in the resonant circuit; the transformer M1 can be a tapped transformer, which is used to perform power isolation transmission.

[0052] The rectifier circuit 33 includes a fifth-phase bridge arm composed of a first diode D1 and a second diode D2, a sixth-phase bridge arm composed of a third diode D3 and a fourth diode D4, and a filter capacitor C3. The midpoint of the fifth-phase bridge arm is connected to the first output terminal of the secondary side of the transformer M1, and the midpoint of the sixth-phase bridge arm is connected to the second output terminal of the secondary side of the transformer M1; the fifth bus terminals of the fifth-phase bridge arm and the sixth-phase bridge arm are respectively connected to one end of the filter capacitor C3 and the positive electrode of the battery 4, and the sixth bus terminals of the fifth-phase bridge arm and the sixth-phase bridge arm are respectively connected to the other end of the filter capacitor C3 and the negative electrode of the battery 4. The filter capacitor C3 is a battery-side capacitor used for battery-side DC voltage filtering.

[0053] In addition, it should be noted that the rectifier circuit 33 can be a switch tube device or a rectifier diode (such as Figure 2 ), to achieve the transmission of electrical energy.

[0054] The following is a detailed description of the charging control method applied to the above charger. Figure 3 As shown, the method may include the following S301 to S303.

[0055] In S301 , a first voltage of a battery is obtained.

[0056] In the present disclosure, the first voltage of the battery is the voltage across the battery, which is a DC side voltage. The first voltage can be obtained by sampling a voltage sensor or by vehicle message communication.

[0057] In S302, a target operating mode of the LLC circuit is determined according to the first voltage.

[0058] In the present disclosure, the target operation mode is a full-bridge mode or a half-bridge mode.

[0059] In S303, the LLC circuit is controlled to operate according to the target operating mode.

[0060] In the above technical solution, the target working mode of the LLC circuit can be determined according to the battery voltage, and then the LLC circuit can be controlled to work according to the target working mode. Among them, the target working mode is full-bridge mode or half-bridge mode, so that the working mode of the LLC circuit can be dynamically switched according to the battery voltage to avoid the generation of uncontrolled rectifier current, so that the charger can work safely, stably and reliably in various working conditions, and the control method is simple and efficient.

[0061] The specific implementation of determining the target operating mode of the LLC circuit according to the first voltage in S302 is described in detail below.

[0062] Specifically, if the first voltage is less than the first preset voltage, the target operating mode is determined to be the half-bridge mode; if the first voltage is greater than or equal to the first preset voltage, the target operating mode is determined to be the full-bridge mode.

[0063] according to Figure 2 It can be seen from the circuit principle of the circuit topology shown in that in order to ensure that the charger works within a safe range, it is necessary to ensure that the voltage across the bus capacitor C1 (i.e., the second voltage) is Otherwise, uncontrolled rectifier current will be generated, where UacMax is the maximum operating voltage of the AC side of the charger. Therefore, it can be inferred that when the first voltage of the battery is lower than When the LLC circuit operates in full-bridge mode, uncontrolled rectification current will be generated, causing risks to the charger.

[0064] Therefore, the first preset voltage can be set to That is, when the first voltage of the battery is less than When the first voltage of the battery is greater than or equal to When , the LLC circuit works in full-bridge mode to realize the characteristics of full-bridge LLC, where K is the turns ratio of the transformer in the resonant circuit (i.e., the turns ratio of the primary to the secondary of the transformer).

[0065] When the first voltage of the battery changes from greater than or equal to becomes less than When the working mode of the LLC circuit is switched from full-bridge mode to half-bridge mode, the characteristics of the LLC circuit change. At this time, the input-output characteristics become a 2:1 relationship, that is, Ubus=2*K*Udc. In this way, when the working mode of the LLC circuit is switched from full-bridge mode to half-bridge mode, Ubus will be much larger than Thus, the risk of uncontrolled rectification when the AC side voltage of the charger is high can be eliminated. Wherein, Udc is the first voltage of the battery.

[0066] The specific implementation method of controlling the LLC circuit to operate according to the target operating mode in the above S303 is described in detail below.

[0067] Specifically, if the target operating mode is half-bridge mode, the upper bridge arm and the lower bridge arm of the first phase bridge arm are controlled to be complementary to each other with a first duty cycle, and the upper bridge arm of the second phase bridge arm is controlled to be disconnected and the lower bridge arm is controlled to be turned on; if the target operating mode is full-bridge mode, the upper bridge arm and the lower bridge arm of the first phase bridge arm are controlled to be complementary to each other with a first duty cycle, and the upper bridge arm and the lower bridge arm of the second phase bridge arm are controlled to be complementary to each other with the first duty cycle, wherein the upper bridge arm of the first phase bridge arm and the lower bridge arm of the second phase bridge arm are turned on at the same time, and the lower bridge arm of the first phase bridge arm and the upper bridge arm of the second phase bridge arm are turned on at the same time.

[0068] For example, an LLC circuit such as Figure 2 As shown, at this time, if the target working mode is the half-bridge mode, the fifth switch tube T5 and the sixth switch tube T6 are controlled to be complementary turned on with the first duty cycle, and the seventh switch tube T7 is controlled to be continuously turned off and the eighth switch tube T8 is controlled to be continuously turned on; if the target working mode is the full-bridge mode, the fifth switch tube T5 and the sixth switch tube T6 are controlled to be complementary turned on with the first duty cycle, and the seventh switch tube T7 and the eighth switch tube T8 are controlled to be complementary turned on with the first duty cycle, wherein the fifth switch tube T5 and the eighth switch tube T8 are turned on at the same time, and the sixth switch tube T6 and the seventh switch tube T7 are turned on at the same time.

[0069] In addition, according to the abnormal analysis, the working mode of the LLC circuit is distinguished by the first preset voltage as the critical point. It can be inferred that in the two working modes (i.e., full-bridge mode and half-bridge mode), the voltage Ubus across the bus capacitor C1 is quite different. In the half-bridge mode, Ubus = 2*K*Udc, and in the full-bridge mode, Ubus = K*Udc. In this way, when the LLC circuit switches from the half-bridge mode to the full-bridge mode, the input voltage of the LLC circuit (i.e., Ubus) is too high, resulting in a very large current in the resonant cavity, which puts the charger at risk of damage. For the same conduction time, the higher the input voltage of the LLC circuit, the greater the current flowing through the resonant circuit.

[0070] In order to avoid the generation of large current in the resonant cavity when the LLC circuit switches from half-bridge mode to full-bridge mode, the following method is proposed:

[0071] To ensure that the charger operates within a safe range, the voltage across the bus capacitor C1 must be Otherwise, an uncontrolled rectifier current will be generated, that is, the voltage across the bus capacitor C1 is (i.e., the second preset voltage) is used as the boundary to distinguish whether an uncontrolled rectifier current is generated. When the LLC circuit ends its operation in half-bridge mode, that is, when the LLC circuit switches from half-bridge mode to full-bridge mode, it is necessary to determine the relationship between the voltage Ubus across the bus capacitor C1 and the second preset voltage. When Ubus is less than (here only slightly less than) the second preset voltage, the LLC circuit can directly switch from half-bridge mode to full-bridge mode; when Ubus is greater than or equal to the second preset voltage, the LLC circuit does not directly switch from half-bridge mode to full-bridge mode, but controls the upper and lower bridge arms of each phase bridge arm in the inverter circuit to switch between the upper and lower bridge arms. The LLC circuit is controlled to operate in the above-mentioned full-bridge mode only after a duty cycle smaller than the above-mentioned first duty cycle is complementary turned on to discharge the bus capacitor voltage in an open loop until Ubus is less than the second preset voltage (i.e., the upper bridge arm and the lower bridge arm of the first phase bridge arm are controlled to be complementary turned on with the first duty cycle, and the upper bridge arm and the lower bridge arm of the second phase bridge arm are controlled to be complementary turned on with the first duty cycle, wherein the upper bridge arm of the first phase bridge arm and the lower bridge arm of the second phase bridge arm are turned on at the same time, and the lower bridge arm of the first phase bridge arm and the upper bridge arm of the second phase bridge arm are turned on at the same time).

[0072] Specifically, when the target working mode is the full-bridge mode, before the step of controlling the upper bridge arm and the lower bridge arm of the first phase bridge arm to be complementary turned on with a first duty cycle, the above-mentioned controlling the LLC circuit to work according to the target working mode (i.e., S303) may further include the following steps:

[0073] Acquire a second voltage of the bus capacitor;

[0074] If the second voltage is less than the second preset voltage, the steps of controlling the upper bridge arm and the lower bridge arm of the first phase bridge arm to be complementary turned on at the first duty cycle, and controlling the upper bridge arm and the lower bridge arm of the second phase bridge arm to be complementary turned on at the first duty cycle are performed, wherein the ratio of the second preset voltage to the first preset voltage is equal to the turns ratio of the transformer in the resonant circuit;

[0075] If the second voltage is greater than or equal to the second preset voltage, the upper bridge arm and the lower bridge arm of the first phase bridge arm are controlled to be complementary turned on at the second duty cycle, and the upper bridge arm and the lower bridge arm of the second phase bridge arm are controlled to be complementary turned on at the second duty cycle, wherein the upper bridge arm of the first phase bridge arm and the lower bridge arm of the second phase bridge arm are turned on at the same time, the lower bridge arm of the first phase bridge arm and the upper bridge arm of the second phase bridge arm are turned on at the same time, and the second duty cycle is less than the first duty cycle. For example, the first duty cycle is 50% and the second duty cycle is 10%.

[0076] In the above embodiment, when Ubus is greater than or equal to the second preset voltage, the LLC circuit does not directly switch from the half-bridge mode to the full-bridge mode, but controls the upper bridge arm and the lower bridge arm of each phase bridge arm in the inverter circuit to be complementary turned on with a duty cycle smaller than the above-mentioned first duty cycle, so that the conduction duty cycle of the upper bridge arm and the lower bridge arm of each phase bridge arm in the inverter circuit is limited, that is, the conduction time of the upper bridge arm and the lower bridge arm of each phase bridge arm in the inverter circuit is reduced, so that the resonant cavity current can be effectively suppressed, thereby avoiding the generation of large current in the resonant cavity when the LLC circuit switches from the half-bridge mode to the full-bridge mode, thereby improving the safety and stability of the charger.

[0077] In addition, the above method may further include the following steps (1) to (4):

[0078] (1) Obtaining current power information of the AC side of the charger and the second voltage of the bus capacitor.

[0079] In the present disclosure, the power information includes the current current and the current voltage of the AC side.

[0080] For example, the current current on the AC side of the charger can be obtained through a current sensor, and the current voltage on the AC side of the charger and the second voltage of the bus capacitor can be obtained through a voltage sensor. In this way, the current power information on the AC side of the charger and the second voltage of the bus capacitor can be clearly identified, providing data support for current adjustment on the AC side.

[0081] (2) Determine the steady-state target current on the AC side.

[0082] In the present disclosure, the steady-state target current is the current value that the AC side of the charger should correspond to when the charger is in a stable and efficient optimal working state.

[0083] (3) Determine the target current value of the AC side according to the current voltage and the steady-state target current.

[0084] For example, the current voltage u a (i.e., the voltage of the grid output current), extract the phase of the AC output of the grid; for example, the product of the steady-state target current and the phase of the AC output of the grid can be determined as the target current value. Figure 4 As shown, if the steady-state target current is I a_ref , the phase of the AC power output from the power grid determined by the phase-locked loop is coswt, then I a_ref *coswt is the target current value I a_ref1 .

[0085] (4) According to the target current value, the current current, the current voltage and the second voltage, the power factor correction circuit is controlled to perform power factor correction.

[0086] Specifically, if Figure 4 As shown, the second voltage Ubus and the current voltage u a Input into the divider to obtain the feedforward u of the closed-loop control result a / Ubus; at the same time, the target current value I a_ref1 With the current i a It is input into the controller to obtain the feedback of the closed-loop control result; then, the difference between the feedforward amount and the feedback amount is used as the modulation wave and passed into the PWM generator to obtain the duty cycle of the power factor correction circuit (PFC). Finally, the duty cycle of the power factor correction circuit can be adjusted so that the current on the AC side follows the target current value, thereby achieving power factor correction.

[0087] The specific implementation method of determining the steady-state target current on the AC side in (2) above is described in detail below. Specifically, it can be achieved by the following steps (21) and (22):

[0088] (21) Determine the target charging power on the AC side.

[0089] In the present disclosure, the target charging power refers to the power on the AC side of the charger when the charger is in a stable and efficient optimal working state. Specifically, the target charging power can be determined as the minimum value of the maximum output power of the power grid, the current output power of the power grid, the maximum charging power allowed by the battery management system, the maximum power allowed by the cable, and the maximum charging power of the charger.

[0090] For example, the maximum output power of the power grid and the maximum power allowed by the cable can be determined according to the content of the national standard GBT18487.1-2015; the current output power of the power grid can be determined by the power sensor pre-set on the power grid; the maximum charging power allowed by the battery management system can be determined according to the relevant parameter information of the battery; the maximum charging power of the charger can be determined according to the hardware device selection of the charger, that is, it belongs to the inherent attribute parameter of the charger. The above-mentioned powers to be selected are the maximum power corresponding to the power grid, battery, cable, charger and the current output power of the power grid. Therefore, the minimum value is selected as the target charging power. On the one hand, it can ensure that the power grid, battery and cables used to connect the various parts of the charger are in a safe working state when the charger is working, reducing the possibility of damage to the electronic components on the related circuits; on the other hand, it can ensure that the power on the AC side of the charger can reach its maximum value while ensuring the safety of work. Therefore, if the power on the AC side of the charger is the target charging power, the charger can be in a stable and efficient optimal working state.

[0091] (22) According to the target charging power, the steady-state target current on the AC side is determined.

[0092] In the present disclosure, the steady-state target current on the AC side is a current value determined according to the target charging power. The steady-state target current can be determined according to the quotient of the target charging power and the effective value of the AC voltage output by the power grid.

[0093] In addition, the charger control device 5 may include:

[0094] a memory having a computer program stored thereon;

[0095] The computer program, when executed by the controller, implements the steps of the charger control method provided by the present disclosure.

[0096] The present disclosure also provides a vehicle, comprising a battery and the charger provided by the present disclosure.

[0097] The preferred embodiments of the present disclosure are described in detail above in conjunction with the accompanying drawings; however, the present disclosure is not limited to the specific details in the above embodiments. Within the technical concept of the present disclosure, a variety of simple modifications can be made to the technical solution of the present disclosure, and these simple modifications all fall within the protection scope of the present disclosure.

[0098] It should also be noted that the various specific technical features described in the above specific embodiments can be combined in any suitable manner without contradiction. In order to avoid unnecessary repetition, the present disclosure will not further describe various possible combinations.

[0099] In addition, various embodiments of the present disclosure may be arbitrarily combined, and as long as they do not violate the concept of the present disclosure, they should also be regarded as the contents disclosed by the present disclosure.

Claims

1. A charger control method, applied to a charger, wherein the charger is a vehicle-mounted charger or a charging pile charger, and the charger comprises an LLC circuit, wherein the LLC circuit is connected to a battery, and wherein: The method comprises: obtaining a first voltage of the battery; Determining a target operating mode of the LLC circuit according to the first voltage, wherein the target operating mode is a full-bridge mode or a half-bridge mode; Controlling the LLC circuit to operate according to the target operating mode; The charger further comprises a power factor correction circuit and a bus capacitor, wherein the power factor correction circuit is connected to the LLC circuit via the bus capacitor; The method further comprises: Acquire current power information of the AC side of the charger and the second voltage of the bus capacitor, wherein the power information includes the current current and the current voltage of the AC side; Determine the minimum value among the maximum output power of the power grid, the current output power of the power grid, the maximum charging power of the battery allowed by the battery management system, the maximum power allowed by the cable, and the maximum charging power of the charger as the target charging power of the AC side; Determine the steady-state target current of the AC side according to the target charging power, wherein the steady-state target current is the current value that the AC side of the charger should correspond to when the charger is in a stable and efficient optimal working state; Determining a target current value of the AC side according to the current voltage and the steady-state target current; The power factor correction circuit is controlled to perform power factor correction according to the target current value, the current current, the current voltage and the second voltage.

2. The method according to claim 1, characterized in that The step of determining a target operating mode of the LLC circuit according to the first voltage includes: If the first voltage is less than a first preset voltage, determining that the target operating mode is the half-bridge mode; If the first voltage is greater than or equal to the first preset voltage, the target operating mode is determined to be the full-bridge mode.

3. The method according to claim 2, characterized in that The LLC circuit comprises an inverter circuit, a resonant circuit and a rectifier circuit connected in sequence, wherein the inverter circuit comprises a first phase bridge arm and a second phase bridge arm; The controlling the LLC circuit to operate according to the target operating mode includes: If the target operating mode is the half-bridge mode, the upper bridge arm and the lower bridge arm of the first phase bridge arm are controlled to be complementary turned on with a first duty cycle, and the upper bridge arm of the second phase bridge arm is controlled to be disconnected and the lower bridge arm is turned on; If the target operating mode is the full-bridge mode, the upper bridge arm and the lower bridge arm of the first phase bridge arm are controlled to be complementary turned on with the first duty cycle, and the upper bridge arm and the lower bridge arm of the second phase bridge arm are controlled to be complementary turned on with the first duty cycle, wherein the upper bridge arm of the first phase bridge arm and the lower bridge arm of the second phase bridge arm are turned on at the same time, and the lower bridge arm of the first phase bridge arm and the upper bridge arm of the second phase bridge arm are turned on at the same time.

4. The method according to claim 3, characterized in that: The charger further includes a bus capacitor, wherein the first bus terminals of the first phase bridge arm and the second phase bridge arm are connected to one end of the bus capacitor, and the second bus terminals of the first phase bridge arm and the second phase bridge arm are connected to the other end of the bus capacitor; When the target operating mode is the full-bridge mode, before the step of controlling the upper bridge arm and the lower bridge arm of the first phase bridge arm to be complementarily turned on at the first duty cycle, controlling the LLC circuit to operate according to the target operating mode further includes: Acquiring a second voltage of the bus capacitor; If the second voltage is less than the second preset voltage, the step of controlling the upper bridge arm and the lower bridge arm of the first phase bridge arm to be complementary turned on with the first duty cycle is executed, wherein the ratio of the second preset voltage to the first preset voltage is equal to the turns ratio of the transformer in the resonant circuit.

5. The method according to claim 4, characterized in that The controlling the LLC circuit to operate according to the target operating mode further includes: If the second voltage is greater than or equal to the second preset voltage, the upper bridge arm and the lower bridge arm of the first phase bridge arm are controlled to be turned on complementarily with the second duty cycle, and the upper bridge arm and the lower bridge arm of the second phase bridge arm are controlled to be turned on complementarily with the second duty cycle, wherein the upper bridge arm of the first phase bridge arm and the lower bridge arm of the second phase bridge arm are turned on at the same time, the lower bridge arm of the first phase bridge arm and the upper bridge arm of the second phase bridge arm are turned on at the same time, and the second duty cycle is less than the first duty cycle.

6. A charger control device, characterized in that: include: a memory having a computer program stored thereon; A controller, wherein when the computer program is executed by the controller, the steps of the method according to any one of claims 1 to 5 are implemented.

7. A charger, comprising a power factor correction circuit, a bus capacitor and an LLC circuit connected in sequence, characterized in that: The charger also includes: The charger control device according to claim 6, wherein the charger control device is connected to the power factor correction circuit and the LLC circuit respectively.

8. A vehicle, characterized in that: The device comprises a battery and a charger according to claim 7.

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