CN118174406A - Dual PFC charging circuit, control method and electric automobile - Google Patents

Abstract

The invention discloses a double PFC charging circuit, a control method and an electric automobile, wherein the method comprises the following steps: determining a target working mode of the double PFC charging circuit; adjusting the working states of the first relay, the second relay and the third relay according to the target working mode; detecting the current and voltage conditions of the double PFC charging circuit in real time through a first current sensor, a second current sensor and a target voltage sensor to obtain a first current, a second current and a target voltage; judging a target working state of the double PFC charging circuit according to the first current, the second current and the target voltage, wherein the target working state comprises: normal work and abnormal work; and when the target working state is abnormal, the double PFC charging circuit is regulated so as to enable the double PFC charging circuit to continue to work. By adopting the embodiment of the invention, the problem that the vehicle-mounted charging circuit does not work due to overload is avoided.

Description

Dual PFC charging circuit, control method and electric automobile

Technical Field

The invention relates to the technical field of electronic circuits, in particular to a double PFC charging circuit, a control method and an electric automobile.

Background

In recent years, the application scene of vehicle-mounted slow charge is more and more complex, and the vehicle-mounted slow charge has a forward charging function and a reverse discharging function (wherein the reverse discharging is divided into modes such as V2L, V2V, V G and the like, V2L can be divided into V2L outside a vehicle and V2L inside the vehicle), at present, a single-path PFC circuit is usually used as a vehicle-mounted charging circuit for vehicle-mounted slow charge, but the vehicle-mounted charging circuit discharges outside the vehicle and discharges inside the vehicle at the same time, and any path of overload can possibly cause the vehicle-mounted charging circuit to be out of work, so that the problem of avoiding the problem of the vehicle-mounted charging circuit being out of work caused by the overload is needed to be solved.

Disclosure of Invention

The embodiment of the invention provides a double PFC charging circuit, a control method and an electric automobile, wherein the double PFC charging circuit comprises two PFC circuits, the two PFC circuits work independently, one PFC circuit is turned off due to overload, and the other PFC circuit can work normally, so that the problem that the vehicle-mounted charging circuit does not work due to overload is avoided.

In a first aspect, an embodiment of the present invention provides a dual PFC charging circuit, where one end of the dual PFC charging circuit is connected to an external AC socket and an internal AC socket, and the other end of the dual PFC charging circuit is connected to a DCDC circuit, and the dual PFC charging circuit is connected to a power battery through the DCDC circuit; wherein,

The dual PFC charging circuit includes: the first relay, the second relay, the third relay, the first current sensor, the second current sensor, the target voltage sensor, the first PFC circuit, the second PFC circuit and the capacitor; the first live wire of the AC socket outside the vehicle is connected with the first end of the first relay, the second end of the first relay is connected with the first end of the first current sensor, the second end of the first current sensor is respectively connected with the first end of the target voltage sensor and the first end of the third relay, and the second end of the target voltage sensor is connected with the first end of the first PFC circuit; the first zero line of the off-board AC socket is connected with the second end of the first PFC circuit; the second live wire of the in-vehicle AC socket is connected with the first end of the second relay, the second end of the second relay is connected with the first end of the second current sensor, the second end of the second current sensor is respectively connected with the second end of the third relay and the first end of the second PFC circuit, and the second zero wire of the in-vehicle AC socket is respectively connected with the first zero wire of the out-vehicle AC socket and the second end of the second PFC circuit; the first PFC circuit and the second PFC circuit are both connected in parallel with the capacitor and are connected with the DCDC circuit through the capacitor.

Optionally, the first PFC circuit includes: the power factor correction circuit comprises a first inductor, a first switching tube, a second switching tube, a third switching tube and a fourth switching tube, wherein a first end of the first inductor is used as a first end of a first PFC circuit to be connected with a second end of the target voltage sensor, and a second end of the first inductor is respectively connected with a source electrode of the first switching tube and a drain electrode of the second switching tube; the first switching tube and the second switching tube form a first PFC bridge arm, the third switching tube and the fourth switching tube form a second PFC bridge arm, and the first PFC bridge arm and the second PFC bridge arm form a first full-bridge PFC; the drain electrode of the fourth switching tube is used as a second end of the first PFC circuit and is respectively connected with the first zero line of the external AC socket and the second zero line of the internal AC socket; the second PFC circuit includes: the first end of the second inductor is used as a first end of the second PFC circuit to be connected with the second end of the second current sensor, and the second end of the second inductor is respectively connected with the source electrode of the fifth switching tube and the drain electrode of the sixth switching tube; the fifth switching tube and the sixth switching tube form a third PFC bridge arm; and the third PFC bridge arm and the second PFC bridge arm form a second full-bridge PFC.

Optionally, the second PFC circuit includes: the first end of the second inductor is used as the first end of the second PFC circuit to be connected with the second end of the second current sensor, and the second end of the second inductor is respectively connected with the source electrode of the fifth switching tube and the drain electrode of the sixth switching tube; the fifth switching tube and the sixth switching tube form a third PFC bridge arm; the seventh switching tube and the eighth switching tube form a fourth PFC bridge arm; the third PFC bridge arm and the fourth PFC bridge arm form a second full-bridge PFC; and the drain electrode of the eighth switching tube is used as a second end of the second PFC circuit to be connected with the second zero line of the in-vehicle AC socket.

Optionally, the first relay is located on the first fire wire, and the second relay is located on the second fire wire, or the first relay is located on the first zero wire, and the second relay is located on the second zero wire.

In a second aspect, an embodiment of the present invention provides a control method of a dual PFC charging circuit, applied to any of the dual PFC charging circuits described in the first aspect, the method including:

determining a target working mode of the double PFC charging circuit;

adjusting the working states of the first relay, the second relay and the third relay according to the target working mode;

detecting the current and voltage conditions of the double PFC charging circuit in real time through the first current sensor, the second current sensor and the target voltage sensor to obtain a first current, a second current and a target voltage;

Judging a target working state of the double PFC charging circuit according to the first current, the second current and the target voltage, wherein the target working state comprises: normal work and abnormal work;

and when the target working state is the abnormal working state, the double PFC charging circuit is regulated so as to enable the double PFC charging circuit to continue working.

Optionally, the adjusting the working states of the first relay, the second relay and the third relay according to the target working mode includes:

When the target working mode is forward charging only, the first relay is closed, the second relay is opened, and the power battery is supplied with power through the first PFC circuit and/or the second PFC circuit; the positive charging is that an external device supplies power to the power battery through the double PFC charging circuit;

When the target working mode is in-vehicle discharging only, the first relay is opened, the second relay is closed, and power is supplied to the in-vehicle AC socket through the first PFC circuit and/or the second PFC circuit;

When the target working mode is that only the vehicle is discharged, the first relay is closed, the second relay is opened, and power is supplied to the AC socket outside the vehicle through the first PFC circuit and/or the second PFC circuit;

When the target working mode is the forward charging and the in-vehicle discharging, if the first relay, the second relay and the third relay are closed, the power battery is supplied with power through the external equipment, and the in-vehicle discharging is performed through the power battery; if the first relay and the second relay are closed, the third relay is opened, the power battery is supplied with power through the external equipment, the direct current output of the first PFC circuit is used as the direct current input of the second PFC circuit, and the direct current input of the second PFC circuit is inverted to the in-vehicle AC socket for use;

When the target working mode is that the vehicle interior discharges and the vehicle exterior discharges at the same time, the first relay and the second relay are closed, and the power is respectively supplied to the vehicle exterior AC socket and the vehicle interior AC socket through the first PFC circuit and the second PFC circuit.

Optionally, the determining the target working state of the dual PFC charging circuit according to the first current, the second current, and the target voltage includes:

When the first current is larger than a first current threshold value, a relay corresponding to a circuit where the first current sensor is positioned is disconnected so as to realize overcurrent protection;

when the second current is larger than a second current threshold value, a relay corresponding to a circuit where the second current sensor is positioned is disconnected so as to realize overcurrent protection;

And continuing to work through the PFC circuit which is not disconnected in the double PFC charging circuit.

Optionally, the method further comprises:

Transmitting the first current, the second current, and the target voltage to a target controller;

Generating a corresponding target PWM control signal by the target controller;

And controlling the working frequency and the duty ratio of the first PFC circuit and the second PFC circuit by the target PWM control signal so as to control the voltage and the frequency of the output voltage of the double PFC charging circuit.

Optionally, the method further comprises:

Controlling the first PFC circuit to work with first power; the first power is between 0 and 3.3 kw;

controlling the second PFC circuit to work with second power; the second power is between 0 and 3.3 kw.

In a third aspect, an embodiment of the present invention provides an electric vehicle, including the dual PFC charging circuit according to the first aspect, a DCDC circuit, and a power battery, where the dual PFC charging circuit is connected to the power battery through the DCDC circuit.

It can be seen that by implementing the embodiment of the present invention, the target operation mode of the dual PFC charging circuit is determined; adjusting the working states of the first relay, the second relay and the third relay according to the target working mode; detecting the current and voltage conditions of the double PFC charging circuit in real time through a first current sensor, a second current sensor and a target voltage sensor to obtain a first current, a second current and a target voltage; judging a target working state of the double PFC charging circuit according to the first current and the second current, wherein the target working state comprises: normal work and abnormal work; when the target working state is abnormal, the double PFC charging circuit is regulated so as to enable the double PFC charging circuit to continue to work, the double PFC charging circuit comprises two PFC circuits, the two PFC circuits work independently, one PFC circuit is turned off due to overload, and the other PFC circuit can work normally, so that the problem that the vehicle-mounted charging circuit does not work due to overload of the load is avoided.

Drawings

In order to more clearly describe the embodiments of the present invention or the technical solutions in the background art, the following description will describe the drawings that are required to be used in the embodiments of the present invention or the background art.

Fig. 1 is a circuit block diagram of a dual PFC charging circuit according to an embodiment of the present invention;

fig. 2 is a schematic structural diagram of a dual PFC charging circuit according to an embodiment of the present invention;

fig. 3 is a schematic structural diagram of another dual PFC charging circuit according to an embodiment of the present invention;

fig. 4 is a schematic structural diagram of another dual PFC charging circuit according to an embodiment of the present invention;

fig. 5 is a schematic structural diagram of another dual PFC charging circuit according to an embodiment of the present invention;

Fig. 6 is a flowchart of a control method of a dual PFC charging circuit according to an embodiment of the present invention.

Detailed Description

In order that those skilled in the art will better understand the present application, a technical solution in the embodiments of the present application will be clearly and completely described below with reference to the accompanying drawings in which it is apparent that the described embodiments are only some embodiments of the present application, not all embodiments. All other embodiments, which can be made by those skilled in the art based on the embodiments of the application without making any inventive effort, are intended to be within the scope of the application.

The terms first, second and the like in the description and in the claims and in the above-described figures are used for distinguishing between different objects and not necessarily for describing a sequential or chronological order. Furthermore, the terms "comprise" and "have," as well as any variations thereof, are intended to cover a non-exclusive inclusion. For example, a process, method, system, article, or apparatus that comprises a list of steps or elements is not limited to only those listed steps or elements but may include other steps or elements not listed or inherent to such process, method, article, or apparatus.

Reference herein to "an embodiment" means that a particular feature, structure, or characteristic described in connection with the embodiment may be included in at least one embodiment of the application. The appearances of such phrases in various places in the specification are not necessarily all referring to the same embodiment, nor are separate or alternative embodiments mutually exclusive of other embodiments. Those of skill in the art will explicitly and implicitly appreciate that the embodiments described herein may be combined with other embodiments.

In recent years, the application scene of vehicle-mounted slow charge (OBC) is more and more complex, and the vehicle-mounted slow charge has a forward charging function and a reverse discharging function (wherein the reverse discharging is divided into modes such as V2L, V2V, V G and the like, V2L can be divided into V2L outside a vehicle and V2L inside the vehicle), at present, a single PFC circuit is usually used as a vehicle-mounted charging circuit for carrying out vehicle-mounted slow charge, but the vehicle-mounted charging circuit discharges outside the vehicle and discharges inside the vehicle at the same time, and any path of overload can cause the non-working of the vehicle-mounted charging circuit, so that the problem of non-working of the vehicle-mounted charging circuit caused by overload is to be solved.

In addition, forward charging and reverse discharging may operate simultaneously in certain operating scenarios. In order to meet different application scenes, the embodiment of the invention provides a double PFC charging circuit, a control method and an electric automobile, which avoid the problem that a vehicle-mounted charging circuit is not operated due to overload and can meet the requirements of different application scenes.

Wherein, OBC: on-BoardCharger, vehicle-mounted slow charging;

V2L: vehicle-to-Load, i.e., the Vehicle is supplying power to external loads;

V2V: vehicle-to-Vehicle, i.e., the vehicles are powered by each other;

V2G: vehicle-to-Grid, the Vehicle supplies power to the Grid, i.e., the Vehicle supplies power to the Grid.

Referring to fig. 1, fig. 1 is a circuit block diagram of a dual PFC charging circuit 100 according to an embodiment of the present invention; the dual PFC charging circuit 100 shown in fig. 1:

One end of the double PFC charging circuit 100 is respectively connected with an external AC socket and an internal AC socket, the other end of the double PFC charging circuit 100 is connected with a DCDC circuit, and the double PFC charging circuit 100 is connected with a power battery (HVDC) through the DCDC circuit; the dual PFC charging circuit 100 includes: the first relay K1, the second relay K2, the third relay K3, the first current sensor Cs1, the second current sensor Cs2, the target voltage sensor Vs, the first PFC circuit PFC1, the second PFC circuit PFC2 and the capacitor C; the first live wire L1 of the AC socket outside the vehicle is connected with the first end of the first relay K1, the second end of the first relay K1 is connected with the first end of the first current sensor Cs1, the second end of the first current sensor Cs1 is respectively connected with the first end of the target voltage sensor Vs and the first end of the third relay K3, and the second end of the target voltage sensor Vs is connected with the first end of the first PFC circuit PFC 1; the first zero line N1 of the off-vehicle AC socket is connected with the second end of the first PFC circuit PFC 1; the second live wire L2 of the in-vehicle AC socket is connected with the first end of the second relay K2, the second end of the second relay K2 is connected with the first end of the second current sensor Cs2, the second end of the second current sensor Cs2 is respectively connected with the second end of the third relay K3 and the first end of the second PFC circuit PFC2, and the second zero line N2 of the in-vehicle AC socket is respectively connected with the first zero line N1 of the out-of-vehicle AC socket and the second end of the second PFC circuit PFC 2; the first PFC circuit PFC1 and the second PFC circuit PFC2 are both connected in parallel with a capacitor C and are connected with a DCDC circuit through the capacitor C.

The first PFC circuit PFC1 and the second PFC circuit PFC2 are both connected in parallel with a capacitor C, and are connected to the DCDC circuit through the capacitor C, specifically as follows:

The third end of the first PFC circuit PFC1 is respectively connected with the third end of the second PFC circuit PFC2, the first end of the capacitor C and the first end of the DCDC circuit, the fourth end of the first PFC circuit PFC1 is respectively connected with the fourth end of the second PFC circuit PFC2, the second end of the capacitor C and the second end of the DCDC circuit, and the DCDC circuit is connected with the power battery in parallel.

The first relay K1, the second relay K2, and the third relay K3 are used for controlling the on and off of the dual PFC charging circuit 100, so as to change the working state of the dual PFC charging circuit 100.

The first current sensor Cs1, the second current sensor Cs2, the target voltage sensor Vs, and the method are used for detecting the voltage and the current of the dual PFC charging circuit 100 in the working process, judging the actual operation condition of the dual PFC charging circuit 100 according to the change condition of the voltage and the current, and in addition, when detecting the current or the voltage abnormality of the dual PFC charging circuit 100, uploading the abnormality information in time, and closing the abnormality circuit in the dual PFC charging circuit 100.

The first PFC circuit PFC1 and the second PFC circuit PFC2 are used for controlling waveforms of input currents so as to keep synchronization with waveforms of input voltages, and the problems of serious distortion and electromagnetic interference of current waveforms caused by capacitive loads are solved; the capacitor is used to store energy for release at the appropriate time.

The DCDC circuit is configured to perform power conversion on the dc voltage output by the dual PFC charging circuit 100, so as to charge the power battery; the external device can be a power supply device or electric equipment, and the power battery can be a battery in the electric automobile.

The dual PFC charging circuit 100 may meet different application scenario requirements by controlling the operation modes of the switches and circuits of the three relays, and power control, as follows:

1. Only forward charging: that is, the external device charges the power battery through the dual PFC charging circuit 100 without performing other operations, it may be to close the first relay K1 and open the second relay K2, then, it may be that two PFC circuits simultaneously operate to output 6.6KW or a single PFC operation to output 3.3KW, and then the DCDC circuit outputs 6.6KW of power to charge the power battery, and in this case, the third relay K3 may or may not be closed, however, in order to avoid accidents, it is preferable to open the third relay K3.

2. Forward charging while in-vehicle V2L:

① Operation mode one: simultaneously, the first relay K1, the second relay K2 and the third relay K3 are closed, an external device provides an AC input for the double PFC charging circuit, the AC input can be used as an output of V2L in a vehicle, and the residual power of the V2L power in the vehicle subtracted from the input power of the external device can be continuously used for forward charging.

② And a second working mode: simultaneously, the first relay K1 and the second relay K2 are closed, the third relay K3 is opened, an AC input is provided for the double PFC charging circuit by external equipment to carry out forward charging, in addition, the opening of the third relay K3 can avoid the AC input as the output of V2L in a vehicle, then, the DC output of the first PFC circuit PFC1 can be used as the DC input of the second PFC circuit PFC2 to be inverted for the AC socket in the vehicle to carry out V2L in the vehicle, and the mode has the advantages of adjustable AC output voltage and frequency.

3. V2L in the car and V2L outside the car simultaneously: the first relay K1 and the second relay K2 are closed, the two PFC circuits independently operate to supply power to the AC socket inside the vehicle and the AC socket outside the vehicle, and on the premise that the total power of the AC output does not exceed 6.6KW, the discharge power of the two PFC circuits can be freely distributed, for example, 1kw+5.6kw, 2kw+4.6kw, and the like, and in addition, the third relay K3 may or may not be closed in this case, however, in order to avoid accidents, it is preferable to open the third relay K3.

4. Vehicle V2L only: the first relay K1 is opened, the second relay K2 is closed, and the two PFC circuits can simultaneously work and output 6.6KW or the single PFC work and output 3.3KW to supply power to the AC socket in the vehicle so as to carry out V2L in the vehicle, in other words, the V2L in the vehicle, namely the power battery charges a load connected with the AC socket in the vehicle.

5. Vehicle exterior V2L only: the first relay K1 is closed, the second relay K2 is opened, and the two PFC circuits simultaneously work and output 6.6KW or single PFC work and output 3.3KW to supply power to the AC socket outside the vehicle so as to carry out V2L outside the vehicle, in other words, the V2L outside the vehicle, namely the power battery charges a load connected with the AC socket outside the vehicle.

6. V2V in-vehicle V2L: the first PFC circuit PFC1 can output 3.3KW of CP signal to charge the external vehicle; the second PFC circuit PFC2 can output 3.3KW to supply power to the AC socket in the vehicle, and when the load is overweight, the target controller can detect that the second current sensor Cs2 overflows, the second relay K2 is disconnected, and the influence of the load of the AC socket in the vehicle on V2V is avoided.

The CP signal, which is called a control and guide function signal (Control Pilot Function), is mainly used for monitoring the interactive function between the electric vehicle and the electric vehicle power supply device, specifically, when the vehicle-mounted charger detects that the charging port is completely connected with the charging gun, it communicates the CP signal of the external power supply device with the CP signal of the vehicle-mounted charger, and the process adopts PWM modulation.

The above method is also applicable to the dual PFC charging circuit 100 in fig. 2, 3, 4, and 5.

It should be noted that, the dual PFC charging circuit 100 shown in fig. 1 may be applied to an electric vehicle, for example, for vehicle-mounted slow charging, the target controller may be an automobile controller, and the dual PFC charging circuit 100 may receive a control signal issued by the target controller and adjust a working state of the circuit according to the control signal. The external AC socket and the internal AC socket are power sockets of the electric automobile, and the external AC socket is generally positioned outside the electric automobile, for example, a trunk area or an engine cabin of the electric automobile, can provide alternating current power and can also be used for connecting external equipment, such as an electric tool, a dust collector, an inflator pump and the like; the off-board AC outlet facilitates the use of electrical equipment outside the vehicle by a user when needed, without relying on other external power sources. In-car AC sockets are typically located inside electric vehicles, such as a center console, a rear seat area, or a trunk, etc., which can provide AC power and can also be used to connect various electrical devices, such as notebook computers, cell phone chargers, electric fans, small appliances, etc. The AC socket in the vehicle is convenient for passengers to use electrical equipment in the vehicle, and meets the charging and using requirements of the passengers.

Fig. 2 is a schematic structural diagram of a dual PFC charging circuit 100 according to an embodiment of the present invention; as shown in fig. 2, one end of the double-PFC charging circuit is respectively connected with an external AC socket and an internal AC socket, the other end of the double-PFC charging circuit is connected with a DCDC circuit, and the double-PFC charging circuit is connected with a power battery (HVDC) through the DCDC circuit; the double PFC charging circuit includes: the first relay K1, the second relay K2, the third relay K3, the first current sensor Cs1, the second current sensor Cs2, the target voltage sensor Vs, the first PFC circuit PFC1, the second PFC circuit PFC2 and the capacitor C; the first live wire L1 of the AC socket outside the vehicle is connected with the first end of the first relay K1, the second end of the first relay K1 is connected with the first end of the first current sensor Cs1, and the second end of the first current sensor Cs1 is respectively connected with the first end of the target voltage sensor Vs and the first end of the third relay K3; the second end of the target voltage sensor Vs is connected with the first end of the first PFC circuit PFC 1; the first zero line N1 of the off-vehicle AC socket is connected with the second end of the first PFC circuit PFC 1; the second live wire L2 of the in-vehicle AC socket is connected with the first end of the second relay K2, the second end of the second relay K2 is connected with the first end of the second current sensor Cs2, the second end of the second current sensor Cs2 is respectively connected with the second end of the third relay K3 and the first end of the second PFC circuit PFC2, and the second zero line N2 of the in-vehicle AC socket is respectively connected with the first zero line N1 of the out-of-vehicle AC socket and the second end of the first PFC circuit PFC 1; the first PFC circuit PFC1 and the second PFC circuit PFC2 are both connected in parallel with a capacitor C and are connected with a DCDC circuit through the capacitor C.

Optionally, the first PFC circuit PFC1 includes: the first end of the first inductor H1 is used as the first end of the first PFC circuit PFC1 to be connected with the second end of the target voltage sensor Vs, and the second end of the first inductor H1 is respectively connected with the source electrode of the first switch tube Q1 and the drain electrode of the second switch tube Q2; the first switching tube Q1 and the second switching tube Q2 form a first PFC bridge arm, the third switching tube Q3 and the fourth switching tube Q4 form a second PFC bridge arm, and the first PFC bridge arm and the second PFC bridge arm form a first full-bridge PFC; the drain electrode of the fourth switching tube Q4 is used as the second end of the first PFC circuit PFC1 to be respectively connected with a first zero line N1 of an AC socket outside the vehicle and a second zero line N2 of the AC socket inside the vehicle; the second PFC circuit PFC2 includes: the first end of the second inductor H2 is used as the first end of the second PFC circuit PFC2 to be connected with the second end of the second current sensor, and the second end of the second inductor H2 is respectively connected with the source electrode of the fifth switch tube Q5 and the drain electrode of the sixth switch tube Q6; the fifth switching tube Q5 and the sixth switching tube Q6 form a third PFC bridge arm; the third PFC bridge arm and the second PFC bridge arm form a second full-bridge PFC.

It should be noted that, in fig. 2, since the first PFC circuit PFC1 and the second PFC circuit PFC2 share the same N-line bridge arm, the second end of the first PFC circuit PFC1 and the second end of the second PFC circuit PFC2 are the same, that is, the two ends are the same port.

Optionally, referring to fig. 3, fig. 3 is a schematic structural diagram of another dual PFC charging circuit 100 according to an embodiment of the present invention; as shown in fig. 3, the second PFC circuit PFC2 may further include, on the basis of fig. 2: the first end of the second inductor H2 is used as the first end of the second PFC circuit PFC2 to be connected with the second end of the second current sensor Cs2, and the second end of the second inductor H2 is respectively connected with the source electrode of the fifth switching tube Q5 and the drain electrode of the sixth switching tube Q6; the fifth switching tube Q5 and the sixth switching tube Q6 form a third PFC bridge arm; the seventh switching tube Q7 and the eighth switching tube Q8 form a fourth PFC bridge arm; the third PFC bridge arm and the fourth PFC bridge arm form a second full-bridge PFC; the drain electrode of the fourth switching tube Q4 is used as the second end of the first PFC circuit PFC1 to be connected with a first zero line N1 of an off-vehicle AC socket; the drain electrode of the eighth switching tube Q8 is used as a second end of the second PFC circuit PFC2 and is connected with a second zero line N2 of the in-vehicle AC socket.

Optionally, referring to fig. 4, fig. 4 is a schematic structural diagram of another dual PFC charging circuit 100 according to an embodiment of the present invention; on the basis of fig. 2, the positions of the first relay K1 and the second relay K2 are changed, the first relay K1 being located on the first neutral line N1, and the second relay K2 being located on the second neutral line N2.

Referring to fig. 5, fig. 5 is a schematic diagram of another dual PFC charging circuit 100 according to an embodiment of the present invention, in which positions of a first relay K1 and a second relay K2 are changed based on fig. 3, the first relay K1 is located on a first neutral line N1, and the second relay K2 is located on a second neutral line N2.

Referring to fig. 6, fig. 6 is a flowchart of a control method of a dual PFC charging circuit according to an embodiment of the present invention, and the method may be applied to any of the dual PFC charging circuits described above, and the method may include the following steps:

s601, determining a target working mode of the double PFC charging circuit.

It should be explained that the dual PFC charging circuit may be applied to an electric vehicle.

In an embodiment of the present application, the working modes may include at least one of the following: forward charging, off-vehicle V2L, in-vehicle V2L, V2V, V G, and the like, are not limited herein.

In a specific embodiment, the target working mode of the dual PFC charging circuit may be determined according to the actual situation, for example, when the electric vehicle needs to be charged, the target working mode may be forward charging, or when the electric vehicle needs to charge the mobile phone, the target working mode may be in-vehicle V2L or out-of-vehicle V2L, and the like, which is not limited herein.

S602, adjusting working states of the first relay, the second relay and the third relay according to the target working mode.

In the embodiment of the application, since the target working mode is already determined in the last step, the first relay, the second relay and the third relay can be adjusted to be closed or opened according to the target working mode so as to realize the target working mode.

Optionally, in step S602, the adjusting the working states of the first relay, the second relay, and the third relay according to the target working mode may include the following steps:

A1, when the target working mode is forward charging only, closing the first relay, and opening the second relay, and supplying power to the power battery through the first PFC circuit and/or the second PFC circuit; the positive charging is that an external device supplies power to the power battery through the double PFC charging circuit;

a2, when the target working mode is in-vehicle discharging only, the first relay is opened, the second relay is closed, and power is supplied to the in-vehicle AC socket through the first PFC circuit and/or the second PFC circuit;

A3, when the target working mode is only off-vehicle discharging, closing the first relay, and opening the second relay, and supplying power to the off-vehicle AC socket through the first PFC circuit and/or the second PFC circuit;

A4, when the target working mode is the forward charging and the vehicle interior discharges, if the first relay, the second relay and the third relay are closed, the power battery is supplied with power through the external equipment, and the vehicle interior discharges through the power battery; if the first relay and the second relay are closed, the third relay is opened, the power battery is supplied with power through the external equipment, the direct current output of the first PFC circuit is used as the direct current input of the second PFC circuit, and the direct current input of the second PFC circuit is inverted to the in-vehicle AC socket for use;

a5, when the target working mode is that the vehicle interior discharges and the vehicle exterior discharges, the first relay and the second relay are closed, and the vehicle exterior AC socket and the vehicle interior AC socket are respectively powered through the first PFC circuit and the second PFC circuit.

In the embodiment of the application, the external equipment can be power supply equipment for supplying power to the double PFC charging circuit, or the external equipment can be electric equipment; the power battery may be a battery inside an electric vehicle.

Firstly, introducing a plurality of English abbreviations related to vehicle discharge, for example, V2L is the English abbreviation of vehicle-to-load, and the vehicle supplies power to external loads (external equipment), namely, the vehicle discharges; V2V is English abbreviation of vehicle-to-vehicle, and the vehicles supply power mutually; V2G is the english abbreviation of car to grid, which the car supplies power to.

In a specific embodiment, the working states of the first relay, the second relay and the third relay may be adjusted according to different target working modes, which is specifically as follows:

1. The target operating mode is forward charging only: that is, the external device charges the power battery through the dual PFC charging circuit 100 without performing other operations, may close the first relay and open the second relay, and then, may operate to output 6.6KW simultaneously or 3.3KW singly for the two PFC circuits, and then, the DCDC circuit outputs 6.6KW for charging the power battery, and in this case, the third relay may or may not be closed, however, in order to avoid accidents, it is preferable to open the third relay.

2. The target working mode is positive charging and V2L in the vehicle simultaneously:

① Operation mode one: and meanwhile, the first relay, the second relay and the third relay are closed, an external device provides an AC input for the double PFC charging circuit, the AC input can be used as an output of V2L in a vehicle, and the residual power of the V2L power in the vehicle subtracted from the input power of the external device can be continuously used for forward charging.

② And a second working mode: meanwhile, the first relay and the second relay are closed, the third relay is opened, an AC input is provided for the double PFC charging circuit by external equipment to carry out forward charging, in addition, the opening of the third relay can avoid the AC input as the output of V2L in a vehicle, then, the DC output of the first PFC circuit can be used as the DC input of the second PFC circuit to be inverted to an AC socket in the vehicle for use, and the V2L in the vehicle is carried out.

3. The target working mode is V2L in the vehicle and V2L outside the vehicle at the same time: the first relay and the second relay are closed, the two PFC circuits independently work to supply power to an AC socket in the vehicle and an AC socket outside the vehicle respectively, and on the premise that the total power of AC output does not exceed 6.6KW, the discharging power of the two PFC circuits can be freely distributed, for example, 1KW+5.6KW, 2KW+4.6KW and the like, and in addition, the third relay can be closed or not closed under the condition, however, in order to avoid accidents, the third relay is preferably opened.

4. The target working mode is V2L in the vehicle only: the first relay is opened, the second relay is closed, and the two PFC circuits can work simultaneously to output 6.6KW or the single PFC circuit can work to output 3.3KW to supply power to an AC socket in the vehicle so as to carry out V2L in the vehicle.

5. The target working mode is only the vehicle exterior V2L: the first relay is closed, the second relay is opened, and the two PFC circuits work simultaneously to output 6.6KW or single PFC work to output 3.3KW to supply power to an AC socket outside the vehicle so as to carry out V2L outside the vehicle.

6. The target working mode is V2V and V2L in the vehicle at the same time: outputting a 3.3KWCP signal to an external vehicle, wherein the first PFC circuit can output 3.3KW to charge the external vehicle; the second PFC circuit can output 3.3KW to supply power to the AC socket in the vehicle, and when the load is overweight, the target controller can detect that the second current sensor is overcurrent, and the second relay is disconnected, so that the influence of the load of the AC socket in the vehicle on V2V is avoided.

Optionally, the method further comprises the following steps:

b1, controlling the first PFC circuit to work with first power; the first power is between 0 and 3.3 kw;

b2, controlling the second PFC circuit to work with second power; the second power is between 0 and 3.3 kw.

In the embodiment of the application, the first PFC circuit can be controlled by the target controller to work with the first power; the second PFC circuit may also be controlled by the target controller to operate at a second power. The first power and the second power may be manually adjusted, or may be adjusted by a target controller (e.g., an automobile controller) according to actual conditions, for example, the target controller may adjust the power of the first PFC circuit and the second PFC circuit according to the load requirement of the circuit, and if the load requirement of a certain PFC circuit is higher, the target controller may correspondingly increase the power of the PFC circuit to meet the load requirement, so as to obtain the best performance and efficiency.

It should be explained that the sum of the first power and the second power is less than or equal to 6.6KW; the target controller can adjust the power of the PFC circuit according to the load requirement, and can also adjust the power of the PFC circuit according to other factors such as the electric quantity of a battery, the temperature and the efficiency, so that the working performance of the PFC circuit is optimal.

And S603, detecting the current and voltage conditions of the double PFC charging circuit in real time through the first current sensor, the second current sensor and the target voltage sensor to obtain a first current, a second current and a target voltage.

In an embodiment of the present application, the current sensor may include at least one of: hall sensors, shunts, transformers, etc., without limitation herein, the voltage sensor may include at least one of: voltage dividers, voltage transformers, capacitive sensors, etc., are not limited herein.

In a specific embodiment, the first current sensor is used for detecting the current flowing through the first PFC circuit to obtain a first current, the second current sensor is used for detecting the current flowing through the second PFC circuit to obtain a second current, and the target voltage sensor is used for detecting the voltage of the double PFC charging circuit to obtain a target voltage.

Optionally, the method further comprises the following steps:

31. transmitting the first current, the second current, and the target voltage to a target controller;

32. Generating a corresponding target PWM control signal by the target controller;

33. and controlling the working frequency and the duty ratio of the first PFC circuit and the second PFC circuit by the target PWM control signal so as to control the voltage and the frequency of the output voltage of the double PFC charging circuit.

In the embodiment of the application, the first current, the second current and the target voltage can be transmitted to the target controller; the target controller generates a corresponding target PWM control signal, specifically, a target output value of the PFC circuit may be calculated according to a target voltage and a PFC control algorithm (for example, an average current control method), the target output value is compared with an actual output value of the PFC circuit, a duty cycle or a frequency of the PWM control signal is adjusted according to a comparison result to obtain a target PWM control signal, and an operating frequency and a duty cycle of the first PFC circuit or the second PFC circuit are controlled by the target PWM control signal to control the voltage and the frequency of the output voltage of the dual PFC charging circuit so that the actual output signal approaches to a target value.

S604, judging a target working state of the double PFC charging circuit according to the first current, the second current and the target voltage, wherein the target working state comprises the following steps: normal work and abnormal work.

In the embodiment of the application, the target controller can judge the target working state of the double PFC charging circuit according to the first current, the second current and the target voltage.

Optionally, in step S604, the determining the target operating state of the dual PFC charging circuit according to the first current, the second current and the target voltage may include the following steps:

41. when the first current is larger than a first current threshold value, a relay corresponding to a circuit where the first current sensor is positioned is disconnected so as to realize overcurrent protection;

42. When the second current is larger than a second current threshold value, a relay corresponding to a circuit where the second current sensor is positioned is disconnected so as to realize overcurrent protection;

43. And continuing to work through the PFC circuit which is not disconnected in the double PFC charging circuit.

In the embodiment of the present application, the first current threshold and the second current threshold may be default values or values set by a user.

In a specific embodiment, when the first current is greater than the first current threshold, it may be indicated that the circuit in which the first current sensor is located has an overcurrent, and the relay corresponding to the circuit in which the first current sensor is located may be disconnected, that is, the first relay is disconnected, so that the first PFC circuit is disconnected, so as to implement overcurrent protection;

Similarly, when the second current is greater than the second current threshold, it may be indicated that the circuit in which the second current sensor is located is over-current, and the relay corresponding to the circuit in which the second current sensor is located may be turned off, that is, the second relay is turned off, so that the second PFC circuit is turned off, so as to implement over-current protection; then, the operation can be continued by the PFC circuit which is not disconnected in the double PFC charging circuit.

Thus, overcurrent protection can be realized, and damage to the circuit due to overcurrent is avoided. When overcurrent occurs in the circuit, the corresponding relay is disconnected, the circuit can be rapidly cut off, electronic elements and equipment in the circuit are protected from being damaged, meanwhile, the uninterrupted PFC circuit in the double PFC charging circuit continues to work, the continuity and stability of the charging process can be ensured, and the condition that the charging is interrupted or unstable due to overcurrent protection is avoided.

And S605, when the target working state is the abnormal working state, the double PFC charging circuit is regulated so as to enable the double PFC charging circuit to continue working.

In the embodiment of the application, when the target working state is abnormal, the target controller can be used for adjusting the double PFC charging circuit so as to enable the double PFC charging circuit to continue working, for example, the target controller can be used for adjusting the duty ratio or the frequency of the PWM signal so as to keep the output voltage stable.

It can be seen that by implementing the embodiment of the present invention, the target operation mode of the dual PFC charging circuit is determined; adjusting the working states of the first relay, the second relay and the third relay according to the target working mode; detecting the current and voltage conditions of the double PFC charging circuit in real time through a first current sensor, a second current sensor and a target voltage sensor to obtain a first current, a second current and a target voltage; judging a target working state of the double PFC charging circuit according to the first current and the second current, wherein the target working state comprises: normal work and abnormal work; when the target working state is abnormal, the double PFC charging circuit is regulated so as to enable the double PFC charging circuit to continue to work, the double PFC charging circuit comprises two PFC circuits, the two PFC circuits work independently, one PFC circuit is turned off due to overload, and the other PFC circuit can work normally, so that the problem that the vehicle-mounted charging circuit does not work due to overload of the load is avoided.

The embodiment of the application also provides an electric automobile, which comprises the double PFC charging circuit, the DCDC circuit and the power battery, wherein the double PFC charging circuit is connected with the power battery through the DCDC circuit.

It should be noted that, for simplicity of description, the foregoing method embodiments are all described as a series of acts, but it should be understood by those skilled in the art that the present application is not limited by the order of acts described, as some steps may be performed in other orders or concurrently in accordance with the present application. Further, those skilled in the art will also appreciate that the embodiments described in the specification are all preferred embodiments, and that the acts and modules referred to are not necessarily required for the present application.

In the foregoing embodiments, the descriptions of the embodiments are emphasized, and for parts of one embodiment that are not described in detail, reference may be made to related descriptions of other embodiments.

In the several embodiments provided by the present application, it should be understood that the disclosed apparatus may be implemented in other manners. For example, the above-described apparatus embodiments are merely illustrative, such as the above-described division of units, merely a division of logic functions, and there may be additional manners of dividing in actual implementation, such as multiple units or components may be combined or integrated into another system, or some features may be omitted, or not performed. Alternatively, the coupling or direct coupling or communication connection shown or discussed with each other may be an indirect coupling or communication connection via some interfaces, devices or units, or may be in electrical or other forms.

The units described above as separate components may or may not be physically separate, and components shown as units may or may not be physical units, may be located in one place, or may be distributed over a plurality of network units. Some or all of the units may be selected according to actual needs to achieve the purpose of the solution of this embodiment.

In addition, each functional unit in the embodiments of the present application may be integrated in one processing unit, or each unit may exist alone physically, or two or more units may be integrated in one unit. The integrated units may be implemented in hardware or in software functional units.

The foregoing has outlined rather broadly the more detailed description of embodiments of the application, wherein the principles and embodiments of the application are explained in detail using specific examples, the above examples being provided solely to facilitate the understanding of the method and core concepts of the application; meanwhile, as those skilled in the art will have variations in the specific embodiments and application scope in accordance with the ideas of the present application, the present description should not be construed as limiting the present application in view of the above.

Claims (10)

1. The double PFC charging circuit is characterized in that one end of the double PFC charging circuit is respectively connected with an external AC socket and an internal AC socket, the other end of the double PFC charging circuit is connected with a DCDC circuit, and the double PFC charging circuit is connected with a power battery through the DCDC circuit; wherein,

The dual PFC charging circuit includes: the first relay, the second relay, the third relay, the first current sensor, the second current sensor, the target voltage sensor, the first PFC circuit, the second PFC circuit and the capacitor;

The first live wire of the AC socket outside the vehicle is connected with the first end of the first relay, the second end of the first relay is connected with the first end of the first current sensor, the second end of the first current sensor is respectively connected with the first end of the target voltage sensor and the first end of the third relay, and the second end of the target voltage sensor is connected with the first end of the first PFC circuit; the first zero line of the off-board AC socket is connected with the second end of the first PFC circuit;

The second live wire of the in-vehicle AC socket is connected with the first end of the second relay, the second end of the second relay is connected with the first end of the second current sensor, the second end of the second current sensor is respectively connected with the second end of the third relay and the first end of the second PFC circuit, and the second zero wire of the in-vehicle AC socket is respectively connected with the first zero wire of the out-vehicle AC socket and the second end of the second PFC circuit;

The first PFC circuit and the second PFC circuit are both connected in parallel with the capacitor and are connected with the DCDC circuit through the capacitor.

2. The dual PFC charging circuit of claim 1, wherein the first PFC circuit comprises: a first inductor, a first switching tube, a second switching tube, a third switching tube and a fourth switching tube, wherein,

The first end of the first inductor is used as the first end of the first PFC circuit to be connected with the second end of the target voltage sensor, and the second end of the first inductor is respectively connected with the source electrode of the first switching tube and the drain electrode of the second switching tube; the first switching tube and the second switching tube form a first PFC bridge arm, the third switching tube and the fourth switching tube form a second PFC bridge arm, and the first PFC bridge arm and the second PFC bridge arm form a first full-bridge PFC; the drain electrode of the fourth switching tube is used as a second end of the first PFC circuit and is respectively connected with the first zero line of the external AC socket and the second zero line of the internal AC socket;

The second PFC circuit includes: a second inductor, a fifth switching tube and a sixth switching tube, wherein,

The first end of the second inductor is used as the first end of the second PFC circuit to be connected with the second end of the second current sensor, and the second end of the second inductor is respectively connected with the source electrode of the fifth switching tube and the drain electrode of the sixth switching tube; the fifth switching tube and the sixth switching tube form a third PFC bridge arm; and the third PFC bridge arm and the second PFC bridge arm form a second full-bridge PFC.

3. The dual PFC charging circuit of claim 2, wherein the second PFC circuit comprises: the second inductor, the fifth switching tube, the sixth switching tube, the seventh switching tube and the eighth switching tube,

The first end of the second inductor is used as the first end of the second PFC circuit to be connected with the second end of the second current sensor, and the second end of the second inductor is respectively connected with the source electrode of the fifth switching tube and the drain electrode of the sixth switching tube; the fifth switching tube and the sixth switching tube form a third PFC bridge arm; the seventh switching tube and the eighth switching tube form a fourth PFC bridge arm; the third PFC bridge arm and the fourth PFC bridge arm form a second full-bridge PFC; and the drain electrode of the eighth switching tube is used as a second end of the second PFC circuit to be connected with the second zero line of the in-vehicle AC socket.

4. A dual PFC charging circuit according to any of claims 1-3, wherein the first relay is located on the first fire line and the second relay is located on the second fire line or the first relay is located on the first zero line and the second relay is located on the second zero line.

5. A control method of a dual PFC charging circuit according to any of claims 1 to 4, the method comprising:

determining a target working mode of the double PFC charging circuit;

adjusting the working states of the first relay, the second relay and the third relay according to the target working mode;

detecting the current and voltage conditions of the double PFC charging circuit in real time through the first current sensor, the second current sensor and the target voltage sensor to obtain a first current, a second current and a target voltage;

Judging a target working state of the double PFC charging circuit according to the first current, the second current and the target voltage, wherein the target working state comprises: normal work and abnormal work;

and when the target working state is the abnormal working state, the double PFC charging circuit is regulated so as to enable the double PFC charging circuit to continue working.

6. The method of claim 5, wherein said adjusting the operating states of the first relay, the second relay, and the third relay according to the target operating mode comprises:

When the target working mode is forward charging only, the first relay is closed, the second relay is opened, and the power battery is supplied with power through the first PFC circuit and/or the second PFC circuit; the positive charging is that an external device supplies power to the power battery through the double PFC charging circuit;

When the target working mode is in-vehicle discharging only, the first relay is opened, the second relay is closed, and power is supplied to the in-vehicle AC socket through the first PFC circuit and/or the second PFC circuit;

When the target working mode is that only the vehicle is discharged, the first relay is closed, the second relay is opened, and power is supplied to the AC socket outside the vehicle through the first PFC circuit and/or the second PFC circuit;

When the target working mode is the forward charging and the in-vehicle discharging, if the first relay, the second relay and the third relay are closed, the power battery is supplied with power through the external equipment, and the in-vehicle discharging is performed through the power battery; if the first relay and the second relay are closed, the third relay is opened, the power battery is supplied with power through the external equipment, the direct current output of the first PFC circuit is used as the direct current input of the second PFC circuit, and the direct current input of the second PFC circuit is inverted to the in-vehicle AC socket for use;

When the target working mode is that the vehicle interior discharges and the vehicle exterior discharges at the same time, the first relay and the second relay are closed, and the power is respectively supplied to the vehicle exterior AC socket and the vehicle interior AC socket through the first PFC circuit and the second PFC circuit.

7. The method of claim 5, wherein determining the target operating state of the dual PFC charging circuit based on the first current, the second current, and the target voltage comprises:

When the first current is larger than a first current threshold value, a relay corresponding to a circuit where the first current sensor is positioned is disconnected so as to realize overcurrent protection;

when the second current is larger than a second current threshold value, a relay corresponding to a circuit where the second current sensor is positioned is disconnected so as to realize overcurrent protection;

And continuing to work through the PFC circuit which is not disconnected in the double PFC charging circuit.

8. The method of any one of claims 6 or 7, wherein the method further comprises:

Transmitting the first current, the second current, and the target voltage to a target controller;

Generating a corresponding target PWM control signal by the target controller;

And controlling the working frequency and the duty ratio of the first PFC circuit and the second PFC circuit by the target PWM control signal so as to control the voltage and the frequency of the output voltage of the double PFC charging circuit.

9. The method of claim 8, wherein the method further comprises:

Controlling the first PFC circuit to work with first power; the first power is between 0 and 3.3 kw;

controlling the second PFC circuit to work with second power; the second power is between 0 and 3.3 kw.

10. An electric vehicle, characterized by comprising a dual PFC charging circuit according to any of claims 1-4, a DCDC circuit and a power battery, the dual PFC charging circuit being connected with the power battery through the DCDC circuit.