Power conversion device and vehicle-mounted charging system

Abstract

The invention discloses a power conversion device and a vehicle-mounted charging system. The power conversion device comprises a coupler, a direct current charging seat, a rechargeable battery and a power conversion circuit, the power conversion circuit comprises a wireless charging circuit and a direct current charging circuit which are connected through a switch, and by controlling the switch, the wireless charging circuit is controlled to charge the rechargeable battery through a coupler or the direct current charging circuit and a direct current charging seat are controlled to charge the rechargeable battery; the direct current charging circuit is connected to the rechargeable battery after voltage conversion through switch control or is directly connected to the rechargeable battery in a breakover mode. The wireless charging circuit has the advantages that wireless charging, direct-current variable-voltage charging and direct-current direct conduction charging are achieved through the circuit, the utilization rate of switches and circuit elements is increased, material use is reduced, and cost is reduced.

Description

Technical Field

[0001] The invention relates to a power conversion device and a vehicle-mounted charging system, belonging to the technical field of power conversion. Background Art

[0002] Wireless charging of electric vehicles can avoid manual operation and greatly improve the convenience of charging. However, wireless charging has a complex structure and high cost.

[0003] In addition, the output of existing wired DC charging piles is mostly around 400V, while the power batteries of electric vehicles are generally beginning to use high-voltage batteries of around 800V, resulting in the existing installed charging piles being unable to adapt to the new 800V power battery vehicles, causing a waste of resources.

[0004] In order to support DC charging and wireless charging in the prior art, two independent sets of power conversion equipment are required, one for wired DC charging and the other for wireless charging. The two sets of power conversion equipment increase the cost and system volume, and the increase in components increases the probability of error. Summary of the invention

[0005] The technical problem to be solved by the present invention is to overcome the defects of the prior art and provide a power conversion device and a vehicle-mounted charging system, which integrate wireless charging and wired charging, and can realize both wireless charging function and DC voltage change function by controlling the switch.

[0006] In order to solve the above technical problems, the present invention provides a power conversion device, comprising: a coupler, a DC charging seat, a rechargeable battery, and also comprising: a power conversion circuit; The power conversion circuit includes a wireless charging circuit and a DC charging circuit connected by a switch. By controlling the switch, the wireless charging circuit is controlled to charge the rechargeable battery using a coupler or the DC charging circuit and a DC charging stand are controlled to charge the rechargeable battery. The DC charging circuit is connected to the rechargeable battery after voltage conversion through switch control or is directly connected to the rechargeable battery.

[0007] Furthermore, the power conversion circuit includes: a coil L2, a capacitor C 2A 、Inductance L FA , switch S1, switch S4, capacitor C0; One end of coil L2 is connected to capacitor C 2A One end, capacitor C 2A The other end is connected to the inductor L FA one end, one end of switch S1 and one end of switch S4; The other end of coil L2 is connected to the negative pole of the DC charging base, the other end of switch S4, one end of capacitor C0 and the negative pole of the rechargeable battery; Inductance L FA The other end is connected to the positive pole of the DC charging base, and the other end of the switch S1 is connected to the other end of the capacitor C0 and the positive pole of the rechargeable battery.

[0008] Furthermore, the power conversion circuit includes: a coil L2, a capacitor C 2A 、Inductance L FA , switch S1, switch S4, capacitor C0; One end of coil L2 is connected to capacitor C 2A One end, capacitor C 2A The other end is connected to the positive pole of the DC charging base and the inductor L FA One end, inductor L FA The other end is connected to one end of switch S1 and one end of switch S4; The other end of coil L2 is connected to the negative pole of the DC charging base, the other end of switch S4, one end of capacitor C0 and the negative pole of the rechargeable battery; The other end of the switch S1 is connected to the other end of the capacitor C0 and the positive electrode of the rechargeable battery.

[0009] Furthermore, the power conversion circuit further includes: an input capacitor C X ; Connect the input capacitor C between the positive and negative electrodes of the DC charging station. X .

[0010] Furthermore, the power conversion circuit further includes: a switch Q1 and an input capacitor C X ; In the inductor L FA Connect switch Q1 between the positive pole of the DC charging station; Connect input capacitor C between the positive and negative poles of the DC charging station. X .

[0011] Furthermore, the power conversion circuit further includes: a switch Q2; The switch Q2 is connected between the positive pole of the DC charging base and the other end of the switch S1.

[0012] Furthermore, the power conversion circuit includes: a coil L2, a capacitor C 2B 、Inductance L FB , switch S1, switch S2, switch S3, switch S4, capacitor C0; One end of the coil L2 is connected to one end of the switch S1 and one end of the switch S4 respectively, and the other end of the switch S1 is connected to one end of the switch S2, one end of the capacitor C0 and the positive electrode of the rechargeable battery respectively; The other end of coil L2 is connected to capacitor C 2B One end, capacitor C 2B The other end is connected to the positive pole of the DC charging stand and the inductor L FB One end, inductor L FBThe other end is connected to the other end of switch S2 and one end of switch S3 respectively; The negative pole of the DC charging base is respectively connected to the other end of the switch S4, the other end of the switch S3, the other end of the capacitor C0 and the negative pole of the rechargeable battery.

[0013] Furthermore, the power conversion circuit further includes: a capacitor C 2A , capacitor C F and inductor L FA ; Capacitor C 2A and inductor L FA Connected in series between one end of coil L2 and one end of switch S1; Capacitor C F One end is connected to capacitor C 2A and inductor L FA Between, capacitor C F The other end is connected to the capacitor C 2B and inductor L FB between.

[0014] Furthermore, the power conversion circuit further includes: a switch Q1 and an input capacitor C X ; The capacitor C 2B A switch Q1 is connected between the other end and the positive pole of the DC charging station; Connect input capacitor C between the positive and negative poles of the DC charging station. X .

[0015] Furthermore, the power conversion circuit includes: a coil L2, a capacitor C 2A , capacitor C 2B , capacitor C F 、Inductance L FA 、Inductance L FB , switch S1, switch S2, switch S3, switch S4, capacitor C0; One end of coil L2 is connected to capacitor C 2A One end, capacitor C 2A The other end is connected to capacitor C F One end, inductor L FA One end and the positive pole of the DC charging stand, inductor L FA The other end is connected to one end of switch S1 and one end of switch S4 respectively, and the other end of switch S1 is connected to one end of switch S2, one end of capacitor C0 and the positive electrode of the rechargeable battery respectively; The other end of coil L2 is connected to capacitor C 2B One end, capacitor C 2B The other end is connected to capacitor C F The other end, the negative pole of the DC charging station and the inductor L FB One end, inductor L FBThe other end is respectively connected to the other end of switch S2 and one end of switch S3, and the other end of switch S3 is respectively connected to the other end of switch S4, the other end of capacitor C0 and the negative electrode of the rechargeable battery.

[0016] Furthermore, the power conversion circuit further includes: a switch Q1 and an input capacitor C X ; The capacitor C 2A A switch Q1 is connected between the other end and the positive pole of the DC charging station; Connect an input capacitor C between the positive pole of the DC charging base and the other end of switch S3. X .

[0017] Further, the DC charging station positive electrode includes a contact port P1 and a contact port P2; The contact port P1 and the capacitor C 2A The other end is connected to the contact port P2 and the capacitor C 2B The other end is connected.

[0018] Furthermore, the DC charging station positive electrode includes a contact port P1, a contact port P2 and a contact port P3, and the power conversion device also includes: an input capacitor C X ; The contact port P1 and the capacitor C 2A The other end is connected to the contact port P2 and the capacitor C 2B The other end is connected to the input capacitor C between the contact port P3 and the negative electrode of the DC charging base X .

[0019] Furthermore, the power conversion circuit further includes: a switch Q1 and a switch Q2; The positive electrode of the DC charging base and the capacitor C 2B The other end is connected with switch Q1; The positive electrode of the DC charging base and the capacitor C 2A The other end is connected with switch Q2.

[0020] Furthermore, the power conversion circuit further includes: a switch Q1, a switch Q2 and a switch Q3; The positive electrode of the DC charging base and the capacitor C 2B The other end is connected with switch Q1; The positive electrode of the DC charging base and the capacitor C 2A The other end is connected with switch Q2; A switch Q3 is connected between the positive electrode of the DC charging base and the other end of the switch S1.

[0021] Furthermore, the power conversion circuit further includes: an input capacitor C X ; Connect the input capacitor C between the positive pole of the DC charging base and the negative pole of the DC charging base. X .

[0022] Furthermore, the power conversion circuit includes: a coil L2, a capacitor C 2A , capacitor C 2B , capacitor C F 、Inductance L FA 、Inductance L FB , switch S1, switch S2, switch S3, switch S4, switch S5, switch S6, switch Q1, capacitor C0; One end of coil L2 is connected to capacitor C 2A One end, capacitor C 2A The other end is connected to capacitor C F One end, inductor L FA One end, inductor L FB One end and one end of switch Q1, inductor L FA The other end is connected to the switch S1 and the switch S6 respectively. The inductor L FB The other end is connected to one end of switch S2 and one end of switch S5 respectively, and the other end of switch S1 is connected to the other end of switch S2, one end of switch S3, one end of capacitor C0 and the positive electrode of the rechargeable battery respectively; The other end of coil L2 is connected to capacitor C 2B One end, capacitor C 2B The other end is connected to capacitor C F the other end, the other end of switch S3 and one end of switch S4; The positive pole of the DC charging base is connected to the other end of the switch Q1; The negative pole of the DC charging base is respectively connected to the other end of the switch S6, the other end of the switch S5, the other end of the switch S4, the other end of the capacitor C0 and the negative pole of the rechargeable battery.

[0023] Furthermore, the power conversion circuit further includes: a switch Q2; The switch Q2 is connected between the other end of the switch S1 and the positive electrode of the DC charging base.

[0024] Furthermore, the power conversion circuit further includes: an input capacitor C X ; Connect the input capacitor C between the positive pole of the DC charging base and the negative pole of the DC charging base. X .

[0025] Furthermore, the power conversion circuit further includes: a switch Q3 and an inductor L FC ; The capacitor C 2B The inductor L is connected between the other end and the other end of the switch S3 and one end of the switch S4. FC ; The inductance LFC Close to capacitor C 2B The switch Q3 is connected between one end of the other end and the positive electrode of the DC charging base.

[0026] A vehicle-mounted charging system comprises a power conversion device and a controller. The controller is connected to the power conversion device and is used to control the on-off of a switch in the power conversion device to perform conversion between wireless charging and wired DC charging.

[0027] The beneficial effects achieved by the present invention are: The present invention realizes wireless charging, DC variable voltage charging, and DC direct conduction charging through a circuit, thereby improving the utilization rate of switches and circuit elements, reducing the use of materials, reducing costs, and reducing volume. BRIEF DESCRIPTION OF THE DRAWINGS

[0028] Figure 1 It is the block diagram of the on-board charging system; Figure 2-1 to Figure 2-6 There are six circuit diagrams of power conversion circuits of half-bridge rectifiers; Figure 3-1 to Figure 3-3 It is a full-bridge rectifier - three circuit diagrams of a power conversion circuit using only a single channel; Figure 4-1 to Figure 4-2 It is a full-bridge rectifier - two circuit diagrams of a power conversion circuit using two channels with the negative channel grounded; Figure 5-1 to Figure 5-2 It is a full-bridge rectifier - two circuit diagrams of a power conversion circuit that can be operated alternately with two channels and connected through a charging station; Figure 6-1 to Figure 6-4 It is a full-bridge rectifier - four circuit diagrams of a power conversion circuit that uses two channels that can be interleaved and connected through switches; Figure 7-1 to Figure 7-4 It is a three-phase full-bridge rectifier - four circuit diagrams of a power conversion circuit that can be operated in two interleaved ways through a switch connection; Figure 8-1 to Figure 8-2 These are three circuit diagrams of a power conversion circuit in which a three-phase full-bridge rectifier-three-phase voltage converter can operate in three-phase interleaving. DETAILED DESCRIPTION

[0029] The present invention will be further described below in conjunction with the accompanying drawings. The following embodiments are only used to more clearly illustrate the technical solution of the present invention, and cannot be used to limit the protection scope of the present invention.

[0030] like Figure 1 As shown, a vehicle-mounted charging system includes a power conversion device and a controller. The controller is connected to the power conversion device and is used to control the switch in the power conversion device to perform conversion between wireless charging and wired DC charging.

[0031] The power conversion device includes: a coupler, a DC charging seat, a rechargeable battery, and a power conversion circuit; The power conversion circuit includes a wireless charging circuit and a DC charging circuit connected by a switch. By controlling the switch, the wireless charging circuit is controlled to charge the rechargeable battery using a coupler or the DC charging circuit and the DC charging seat are controlled to charge the rechargeable battery. The DC charging circuit is connected to the rechargeable battery after voltage conversion through switch control or is directly connected to the rechargeable battery. Embodiment 1, like Figure 2-1 As shown, the power conversion circuit includes: a coil L2, a capacitor C 2A 、Inductance L FA , switch S1, switch S4, capacitor C0; one end of coil L2 is connected to capacitor C 2A One end, capacitor C 2A The other end is connected to the inductor L FA One end of the coil L2 is connected to the negative pole of the DC charging station, the other end of the switch S4, one end of the capacitor C0 and the negative pole of the rechargeable battery; the inductor L FA The other end is connected to the positive pole of the DC charging base, and the other end of the switch S1 is connected to the other end of the capacitor C0 and the positive pole of the rechargeable battery. like Figure 2-3 As shown, the power conversion circuit includes: a coil L2, a capacitor C 2A 、Inductance L FA , switch S1, switch S4, capacitor C0; one end of coil L2 is connected to capacitor C 2A One end, capacitor C 2A The other end is connected to the positive pole of the DC charging base and the inductor L FA One end, inductor L FA The other end is connected to one end of switch S1 and one end of switch S4; the other end of coil L2 is connected to the negative pole of the DC charging socket, the other end of switch S4, one end of capacitor C0 and the negative pole of the rechargeable battery; the other end of switch S1 is connected to the other end of capacitor C0 and the positive pole of the rechargeable battery.

[0032] like Figure 2-2 and Figure 2-5 As shown, in Figure 2-1 and Figure 2-3 Based on the power conversion circuit shown in the figure, the inductor L FA Connect switch Q1 between the positive pole of the DC charging station and Figure 2-2 , Figure 2-4 and Figure 2-5 As shown, an input capacitor C is connected between the positive and negative electrodes of the DC charging station. X , C X As the input capacitor of the voltage converter, it can reduce the electromagnetic interference of the voltage converter.

[0033] Figure 2-1 to Figure 2-4 In the wireless charging, switch S1 and switch S4 are driven and controlled by a pair of complementary PWM signals. Switch S1 and switch S4 form a half-bridge rectifier. Coil L2 is used to receive wireless charging. The resonant network output is rectified into DC by the half-bridge. The resonant network includes capacitor C 2A and coil L2.

[0034] When wired DC charging is performed, switches S1 and S4 are driven and controlled by a pair of complementary PWM signals. FA Together with S1 and S4, a (boost) voltage converter is formed, and input capacitor C is added X Finally, in order not to affect the wireless charging function, a switch Q1 is introduced. When wireless charging is performed, Q1 is disconnected, and when DC charging is performed, Q1 is turned on to form a voltage converter.

[0035] During direct conduction charging, when the output voltage of the external charging pile can directly charge the battery, it can be directly turned on without voltage conversion.

[0036] Not included C X The specific method is: turn on S1, turn off S4, and the positive current flows through the inductor L FA and S1 to charge the battery. FA and output capacitor C O It also forms an LC filter to reduce output ripple.

[0037] Contains C X The specific method is: turn on S1 and Q1, the positive current flows through Q1 and inductor L FA and S1 to charge the battery. FA and output capacitor C O It also forms an LC filter to reduce output ripple.

[0038] like Figure 2-6 As another way of direct charging, Figure 2-1 A switch Q2 is introduced on the basis of the power conversion circuit shown. The switch Q2 is connected between the positive pole of the DC charging base and the other end of the switch S1. When charging is directly turned on, Q2 is turned on, and Q2 is turned off in other states. Direct conduction can reduce losses.

[0039] Figure 2-4 In the circuit, coil L2 and capacitor C 2A 、Inductance L FA , and capacitor C X The LCC resonant network that constitutes wireless charging.

[0040] Figure 2-1 , Figure 2-2 , Figure 2-6 In the circuit, coil L2 and capacitor C 2A The series resonance that constitutes wireless charging.

[0041] Figure 2-3 , Figure 2-5 In the circuit, coil L2, inductor L FA , capacitor C 2A The series resonance that constitutes wireless charging.

[0042] Embodiment 2, like Figure 3-1 As shown, it is a power conversion circuit based on full-bridge rectification, which uses only a single channel, and the negative electrode is directly grounded. The power conversion circuit includes: coil L2, capacitor C 2B 、Inductance L FB , switch S1, switch S2, switch S3, switch S4, capacitor C0; one end of coil L2 is connected to one end of switch S1 and one end of switch S4 respectively, the other end of switch S1 is connected to one end of switch S2, one end of capacitor C0 and the positive electrode of the rechargeable battery respectively; the other end of coil L2 is connected to capacitor C 2B One end, capacitor C 2B The other end is connected to the positive pole of the DC charging stand and the inductor L FB One end, inductor L FB The other end is connected to the other end of switch S2 and one end of switch S3 respectively; the negative pole of the DC charging base is connected to the other end of switch S4, the other end of switch S3, the other end of capacitor C0 and the negative pole of the rechargeable battery respectively.

[0043] like Figure 3-2 As shown, another power conversion circuit includes: coil L2, capacitor C 2A , capacitor C 2B , capacitor C F 、Inductance L FA 、Inductance L FB , switch S1, switch S2, switch S3, switch S4, capacitor C0; one end of coil L2 is connected to capacitor C 2A One end, capacitor C 2A The other end is connected to capacitor C F One end and inductor L FA One end, inductor L FA The other end of coil L2 is connected to one end of switch S1 and one end of switch S4 respectively. The other end of switch S1 is connected to one end of switch S2, one end of capacitor C0 and the positive electrode of the rechargeable battery respectively. The other end of coil L2 is connected to capacitor C 2B One end, capacitor C 2B The other end is connected to capacitor C F The other end, the positive pole of the DC charging stand and the inductor L FB One end, inductor L FBThe other end is connected to the other end of switch S2 and one end of switch S3 respectively; the negative pole of the DC charging base is connected to the other end of switch S4, the other end of switch S3, the other end of capacitor C0 and the negative pole of the rechargeable battery respectively.

[0044] like Figure 3-3 As shown, in Figure 3-2 The power conversion circuit shown is based on the capacitor C 2B Connect switch Q1 between the other end and the positive pole of the DC charging station; connect input capacitor C between the positive pole of the DC charging station and the negative pole of the DC charging station X .

[0045] During wireless charging, the on-off status of S1-S4 is that S1 and S4 are driven and controlled by a pair of complementary PWM signals, and S2 and S3 are driven and controlled by another pair of complementary PWM signals. There is a certain phase difference between the two pairs of complementary PWM signals. S1-S4 constitute a full-bridge rectifier, and the output of the coil and the resonant network is rectified into DC by the full-bridge to improve the processing power capability.

[0046] When the voltage changes, S4 is turned on, S1 is turned off, and L FA、 L FB Together with S2 and S3, they form a voltage converter. Both inductors can be used to reduce input current ripple and improve efficiency. Add input capacitor C X Finally, in order not to affect the wireless charging function, a switch Q1 is introduced. When wireless charging is performed, Q1 is disconnected, and when DC charging is performed, Q1 is turned on to form a voltage converter.

[0047] During direct charging, when the output voltage of the external charging pile can directly charge the battery, it can be directly turned on without voltage conversion.

[0048] Not included C X The specific method is: turn on S2 and S4, the positive current flows through the inductor L FA , L FB And S2, S4, to charge the battery. Among them, the inductor L FA , L FB and output capacitor C O It also forms an LC filter to reduce output ripple.

[0049] Not included C X The specific method is: turn on S2, S4, Q1, and the positive current flows through the inductor L FA , L FB and S2, S4, Q 1, To charge the battery. The inductor L FA , L FB and output capacitor CO It also forms an LC filter to reduce output ripple.

[0050] Figure 3-1 In the circuit, coil L2, inductor L FB , capacitor C 2B The series resonance that constitutes wireless charging.

[0051] Figure 3-2 , Figure 3-3 In the circuit, coil L2 and capacitor C 2A , capacitor C 2B , capacitor C F 、Inductance L FA 、Inductance L FB The LCC resonant network that constitutes wireless charging.

[0052] Embodiment 3, like Figure 4-1 As shown, it is a power conversion circuit based on full-bridge rectification, which uses two channels, and the negative channel is grounded; the power conversion circuit includes: a coil L2, a capacitor C 2A , capacitor C 2B , capacitor C F 、Inductance L FA 、Inductance L FB , switch S1, switch S2, switch S3, switch S4, capacitor C0; one end of coil L2 is connected to capacitor C 2A One end, capacitor C 2A The other end is connected to capacitor C F One end, inductor L FA One end and the positive pole of the DC charging stand, inductor L FA The other end of coil L2 is connected to one end of switch S1 and one end of switch S4 respectively. The other end of switch S1 is connected to one end of switch S2, one end of capacitor C0 and the positive electrode of the rechargeable battery respectively. The other end of coil L2 is connected to capacitor C 2B One end, capacitor C 2B The other end is connected to capacitor C F The other end, the negative pole of the DC charging station and the inductor L FB One end, inductor L FB The other end is respectively connected to the other end of switch S2 and one end of switch S3, and the other end of switch S3 is respectively connected to the other end of switch S4, the other end of capacitor C0 and the negative electrode of the rechargeable battery.

[0053] like Figure 4-2 As shown, in Figure 4-1 The power conversion circuit also includes: switch Q1 and input capacitor C X ; At capacitor C 2A Connect switch Q1 between the other end and the positive pole of the DC charging station; connect input capacitor C between the positive pole of the DC charging station and the other end of switch S3 X .

[0054] Figure 4-1 and 4-2 In the wireless charging, the on-off status of S1-S4 is that S1 and S4 are driven and controlled by a pair of complementary PWM signals, and S2 and S3 are driven and controlled by another pair of complementary PWM signals. There is a certain phase difference between the two pairs of complementary PWM signals. S1-S4 constitute a full-bridge rectifier, and the output of the coil and the resonant network is rectified into DC by the full-bridge. When the voltage changes, S4 is turned on, S1 is turned off, and L FA、 L FB Together with S2 and S3, a voltage converter is formed. Both inductors can be used to reduce input current ripple and improve efficiency. After adding the input capacitor CX, in order not to affect the wireless charging function, a switch Q1 is introduced. When wireless charging is performed, Q1 is disconnected, and when DC charging is performed, Q1 is turned on to form a voltage converter.

[0055] When charging directly, when the output voltage of the external charging pile can directly charge the battery, it can be directly turned on without voltage conversion. C X The specific method is: turn on S2 and S4, the positive current flows through the inductor L FA , L FB And S2, S4, to charge the battery. Among them, the inductor L FA , L FB and output capacitor C O It also forms an LC filter to reduce output ripple. C X The specific method is: turn on S2, S4, Q1, and the positive current flows through the inductor L FA , L FB And S2, S4, Q1, to charge the battery. Among them, the inductor L FA , L FB and output capacitor C O It also forms an LC filter to reduce output ripple.

[0056] Figure 4-1 , Figure 4-2 In the circuit, coil L2 and capacitor C 2A , capacitor C 2B , capacitor C F 、Inductance L FA 、Inductance L FB The LCC resonant network that constitutes wireless charging.

[0057] Embodiment 4, like Figure 5-1 As shown, in Figure 3-2Based on the power conversion circuit, the positive electrode of the DC charging seat includes a contact port P1 and a contact port P2; the contact port P1 and the capacitor C 2A The other end is connected to the contact port P2 and the capacitor C 2B The other end is connected.

[0058] like Figure 5-2 As shown, in Figure 3-3 Based on the power conversion circuit, the positive electrode of the DC charging seat includes a contact port P1, a contact port P2 and a contact port P3, and the power conversion device also includes: an input capacitor C X The contact port P1 and the capacitor C 2A The other end is connected to the contact port P2 and the capacitor C 2B The other end is connected to the input capacitor C between the contact port P3 and the negative electrode of the DC charging base X .

[0059] Figure 5-1 Shown and Figure 5-2 The power conversion circuits shown are all full-bridge rectifiers - using two channels, running interleaved, connected via a charging cradle.

[0060] During wireless charging, the on-off status of S1-S4 is that S1 and S4 are driven and controlled by a pair of complementary PWM signals, and S2 and S3 are driven and controlled by another pair of complementary PWM signals. There is a certain phase difference between the two pairs of complementary PWM signals. S1-S4 constitute a full-bridge rectifier, and the output of the coil and resonant network is rectified into DC by the full-bridge.

[0061] When the voltage changes, Figure 5-1 As shown, the negative pole of the DC charging stand is directly connected to the negative output of the rectifier, L FA , L FB Together with S1-S4, two groups of voltage converters are formed. The two groups of voltage converters can work synchronously or staggered (which can further reduce the output ripple). L FA One end of the contact is connected to port P1, L FB One end is connected to the contact port P2. When the charging gun of the charging pile is connected to the charging base, the positive pole of the charging gun contacts P1 and P2 at the same time.

[0062] like Figure 5-2 As shown, adding input capacitor C X Finally, in order not to affect the wireless charging function, the contact port P3 is introduced. When wireless charging is performed, the capacitor C X There is no contact with the rectifier. When DC charging, the positive pole of the charging gun contacts P1, P2 and P3 at the same time, thereby connecting the capacitor C XConnected to the circuit, the two sets of voltage converters increase power and operate in an interleaved manner, further reducing ripple and improving efficiency.

[0063] When charging directly, when the output voltage of the external charging pile can directly charge the battery, it can be directly turned on without voltage conversion. The specific method is: turn on S2 and S1, and the positive current flows through the inductor L FA , L FB And S1, S2, to charge the battery. Among them, the inductor L FA , L FB and output capacitor C O It also forms an LC filter to reduce output ripple.

[0064] Figure 5-1 , Figure 5-2 In the circuit, coil L2 and capacitor C 2A , capacitor C 2B , capacitor C F 、Inductance L FA 、Inductance L FB The LCC resonant network that constitutes wireless charging.

[0065] Embodiment 5, like Figure 6-1 As shown, in Figure 3-2 Based on the power conversion circuit, switch Q1 and switch Q2 are added; the positive electrode of the DC charging base is connected to the capacitor C 2B The other end is connected to switch Q1; the positive pole of the DC charging base is connected to the capacitor C 2A The other end is connected with switch Q2; like Figure 6-2 As shown, in Figure 6-1 Based on the power conversion circuit, the input capacitor C is connected between the positive electrode of the DC charging base and the negative electrode of the DC charging base. X , which can reduce the electromagnetic interference of the voltage converter.

[0066] Figure 6-1 Shown and Figure 6-2 The power conversion circuits shown are all full-bridge rectifiers - using two channels, interleaved, connected via switches.

[0067] During wireless charging, the on-off status of S1-S4 is that S1 and S4 are driven and controlled by a pair of complementary PWM signals, and S2 and S3 are driven and controlled by another pair of complementary PWM signals. There is a certain phase difference between the two pairs of complementary PWM signals. S1-S4 constitute a full-bridge rectifier, and the output of the coil and resonant network is rectified into DC by the full-bridge.

[0068] When the voltage is converted, the negative pole of the DC charging station is directly connected to the negative pole output of the rectifier, L FA , LFB Together with S1-S4, two groups of voltage converters are formed. The two groups of voltage converters can work synchronously or staggered (which can further reduce the output ripple).

[0069] In order not to affect the wireless charging function, switches Q1 and Q2 are introduced. When wireless charging is performed, Q1 and Q2 are disconnected. When DC charging is performed, Q1 and Q2 are turned on to form a voltage converter.

[0070] When charging directly, when the output voltage of the external charging pile can directly charge the battery, it can be directly turned on without voltage conversion. The specific method is: turn on Q1, Q2, S2, S1, and the positive current flows through the inductor Q1, Q2, L FA , L FB And S1, S2, to charge the battery. Among them, the inductor L FA , L FB and output capacitor C O It also forms an LC filter to reduce output ripple.

[0071] like Figure 6-3 As shown, in Figure 6-1 On the basis of the power conversion circuit, a switch Q3 is connected between the positive pole of the DC charging base and the other end of the switch S1 as another way of direct charging of the full-bridge solution. When directly charging, Q3 is turned on, and Q3 is disconnected in other states.

[0072] like Figure 6-4 As shown, in Figure 6-3 Based on the power conversion circuit, the input capacitor C is connected between the positive electrode of the DC charging base and the negative electrode of the DC charging base. X , which can reduce the electromagnetic interference of the voltage converter.

[0073] Figure 6-1 , Figure 6-2 , Figure 6-3 , Figure 6-4 In the circuit, coil L2 and capacitor C 2A , capacitor C 2B , capacitor C F 、Inductance L FA 、Inductance L FB The LCC resonant network that constitutes wireless charging.

[0074] Embodiment 6, like Figure 7-1 , Figure 7-2 , Figure 7-3 and Figure 7-4 As shown, a three-phase full-bridge rectifier is connected through switches and can be independently switched on and off for charging.

[0075] like Figure 7-1As shown, the power conversion circuit includes: coil L2, capacitor C 2A , capacitor C 2B , capacitor C F 、Inductance L FA 、Inductance L FB , switch S1, switch S2, switch S3, switch S4, switch S5, switch S6, switch Q1, capacitor C0; one end of coil L2 is connected to capacitor C 2A One end, capacitor C 2A The other end is connected to capacitor C F One end, inductor L FA One end, inductor L FB One end and one end of switch Q1, inductor L FA The other end is connected to the switch S1 and the switch S6 respectively. The inductor L FB The other end of the coil L2 is connected to one end of the switch S2 and one end of the switch S5. The other end of the switch S1 is connected to the other end of the switch S2, one end of the switch S3, one end of the capacitor C0 and the positive electrode of the rechargeable battery. The other end of the coil L2 is connected to the capacitor C 2B One end, capacitor C 2B The other end is connected to capacitor C F The positive pole of the DC charging base is connected to the other end of switch Q1; the negative pole of the DC charging base is respectively connected to the other end of switch S6, the other end of switch S5, the other end of switch S4, the other end of capacitor C0 and the negative pole of the rechargeable battery.

[0076] like Figure 7-2 As shown, in Figure 7-1 Based on the power conversion circuit, a switch Q2 is connected between the other end of the switch S1 and the positive pole of the DC charging base, and charging is performed directly when Q2 is turned on.

[0077] like Figure 7-3 As shown, in Figure 7-2 Based on the power conversion circuit, the input capacitor C is connected between the positive electrode of the DC charging base and the negative electrode of the DC charging base. X , which can reduce the electromagnetic interference of the voltage converter.

[0078] like Figure 7-4 As shown, in Figure 7-3 The power conversion circuit is based on the embodiment of the present invention, excluding the through switch Q2.

[0079] During wireless charging, the on-off status of S1-S6 is that S1 and S6 are driven and controlled by the first pair of complementary PWM signals, S2 and S5 are driven and controlled by the second pair of complementary PWM signals, and S3 and S4 are driven and controlled by the third pair of complementary PWM signals. There is a certain phase difference between the first pair of complementary PWM signals and the third pair of complementary PWM signals. S1-S6 constitute a full-bridge rectifier, and the output of the coil and the resonant network is rectified into DC by the full-bridge.

[0080] When the voltage is converted, the negative pole of the DC charging station is directly connected to the negative pole output of the rectifier, L FA , L FB Together with S1, S2, S5, and S6, two groups of voltage converters can work synchronously or staggered (further reducing output ripple). In order not to affect the wireless charging function, switches Q1 and Q2 are introduced. When wireless charging is performed, Q1 and Q2 are disconnected. When DC charging is performed, Q1 is turned on to form a voltage converter, or Q2 is turned on to charge directly.

[0081] When charging directly, when the output voltage of the external charging pile can directly charge the battery, it can be directly turned on without voltage conversion. The specific method is: turn on Q1, S2, S1, and the positive current flows through the inductor Q1, L FA , L FB And S1, S2, to charge the battery. Among them, the inductor L FA , L FB and output capacitor C O It also forms an LC filter to reduce the output ripple. Another method is to introduce switch Q2, which is directly turned on when charging, and turned on when Q2 is turned off in other states.

[0082] Figure 7-1 , Figure 7-2 , Figure 7-3 , Figure 7-4 In the circuit, coil L2 and capacitor C 2A , capacitor C 2B , capacitor C F 、Inductance L FA 、Inductance L FB The LCC resonant network that constitutes wireless charging.

[0083] Embodiment 7, as Figure 8-1 and 8-2 As shown, three-phase full-bridge rectifier - three-phase voltage converter.

[0084] like Figure 8-1 As shown in Figure 8-2, Figure 7-1 and Figure 7-2 Based on the power conversion circuit, the capacitor C 2B The inductor L is connected between the other end and the other end of the switch S3 and one end of the switch S4. FC ; Inductance L FC Close to capacitor C 2B A switch Q3 is connected between one end of the other end and the positive pole of the DC charging base.

[0085] During wireless charging, the on-off status of S1-S6 is that S1 and S6 are driven and controlled by the first pair of complementary PWM signals, S2 and S5 are driven and controlled by the second pair of complementary PWM signals, and S3 and S4 are driven and controlled by the third pair of complementary PWM signals. There is a certain phase difference between the first pair of complementary PWM signals and the third pair of complementary PWM signals. S1-S6 constitute a full-bridge rectifier, and the output of the coil and the resonant network is rectified into DC by the full-bridge.

[0086] When the voltage is converted, the negative pole of the DC charging station is directly connected to the negative pole output of the rectifier, L FA , L FB , L FC Together with S1, S2, S5, S6, S3, and S4, they form three groups of voltage converters, which can work synchronously or staggered (further reducing output ripple). In order not to affect the wireless charging function, switches Q1, Q2, and Q3 are introduced. When wireless charging is performed, Q1, Q2, and Q3 are disconnected; when DC charging is performed, Q1 and Q3 are turned on to form a voltage converter or Q2 is turned on for direct charging.

[0087] Figure 8-1 , Figure 8-2 In the circuit, coil L2 and capacitor C 2A , capacitor C 2B , capacitor C F 、Inductance L FA 、Inductance L FB 、Inductance L FC The LCC resonant network that constitutes wireless charging.

[0088] During direct charging, when the output voltage of the external charging pile can directly charge the battery, it can be directly turned on without voltage conversion.

[0089] The specific method is: turn on Q1, Q3, S2, S1, S3, and the positive current flows through the inductors Q1, Q3, L FA , L FB , L FC And S1, S2, S3, to charge the battery. Among them, the inductor L FA , L FB , L FC and output capacitor C O It also forms an LC filter to reduce the output ripple. Another method is to introduce switch Q2, which is directly turned on when charging, and turned on when Q2 is turned off in other states.

[0090] The above is only a preferred embodiment of the present invention. It should be pointed out that for ordinary technicians in this technical field, several improvements and modifications can be made without departing from the technical principles of the present invention. These improvements and modifications should also be regarded as the scope of protection of the present invention.

Claims

1. A power conversion device, comprising: The coupler, the DC charging stand, and the rechargeable battery are characterized in that they also include: a power conversion circuit; The power conversion circuit includes a wireless charging circuit and a DC charging circuit connected by a switch. By controlling the switch, the wireless charging circuit is controlled to charge the rechargeable battery using a coupler or the DC charging circuit and a DC charging stand are controlled to charge the rechargeable battery. The DC charging circuit is connected to the rechargeable battery after voltage conversion through switch control or is directly connected to the rechargeable battery.

2. The power conversion device according to claim 1, characterized in that: The power conversion circuit includes: a coil L2, a capacitor C 2A 、Inductance L FA , switch S1, switch S4, capacitor C0; One end of coil L2 is connected to capacitor C 2A One end, capacitor C 2A The other end is connected to the inductor L FA one end, one end of switch S1 and one end of switch S4; The other end of coil L2 is connected to the negative pole of the DC charging base, the other end of switch S4, one end of capacitor C0 and the negative pole of the rechargeable battery; Inductance L FA The other end is connected to the positive pole of the DC charging base, and the other end of the switch S1 is connected to the other end of the capacitor C0 and the positive pole of the rechargeable battery.

3. The power conversion device according to claim 1, characterized in that: The power conversion circuit includes: a coil L2, a capacitor C 2A 、Inductance L FA , switch S1, switch S4, capacitor C0; One end of coil L2 is connected to capacitor C 2A One end, capacitor C 2A The other end is connected to the positive pole of the DC charging base and the inductor L FA One end, inductor L FA The other end is connected to one end of switch S1 and one end of switch S4; The other end of coil L2 is connected to the negative pole of the DC charging base, the other end of switch S4, one end of capacitor C0 and the negative pole of the rechargeable battery; The other end of the switch S1 is connected to the other end of the capacitor C0 and the positive electrode of the rechargeable battery.

4. The power conversion device according to claim 3, characterized in that: The power conversion circuit also includes: an input capacitor C X ; Connect the input capacitor C between the positive and negative electrodes of the DC charging station. X .

5. The power conversion device according to claim 2 or 3, characterized in that: The power conversion circuit also includes: a switch Q1 and an input capacitor C X ; In the inductor L FA Connect switch Q1 between the positive pole of the DC charging station; Connect input capacitor C between the positive and negative poles of the DC charging station. X .

6. The power conversion device according to claim 2, 3 or 4, characterized in that: The power conversion circuit further includes: a switch Q2; The switch Q2 is connected between the positive pole of the DC charging base and the other end of the switch S1.

7. The power conversion device according to claim 1, characterized in that: The power conversion circuit includes: a coil L2, a capacitor C 2B 、Inductance L FB , switch S1, switch S2, switch S3, switch S4, capacitor C0; One end of the coil L2 is connected to one end of the switch S1 and one end of the switch S4 respectively, and the other end of the switch S1 is connected to one end of the switch S2, one end of the capacitor C0 and the positive electrode of the rechargeable battery respectively; The other end of coil L2 is connected to capacitor C 2B One end, capacitor C 2B The other end is connected to the positive pole of the DC charging stand and the inductor L FB One end, inductor L FB The other end is connected to the other end of switch S2 and one end of switch S3 respectively; The negative pole of the DC charging base is respectively connected to the other end of the switch S4, the other end of the switch S3, the other end of the capacitor C0 and the negative pole of the rechargeable battery.

8. The power conversion device according to claim 7, characterized in that: The power conversion circuit also includes a capacitor C 2A , capacitor C F and inductor L FA ; Capacitor C 2A and inductor L FA Connected in series between one end of coil L2 and one end of switch S1; Capacitor C F One end is connected to capacitor C 2A and inductor L FA Between, capacitor C F The other end is connected to the capacitor C 2B and inductor L FB between.

9. The power conversion device according to claim 7 or 8, characterized in that: The power conversion circuit also includes: a switch Q1 and an input capacitor C X ; The capacitor C 2B A switch Q1 is connected between the other end and the positive pole of the DC charging station; Connect input capacitor C between the positive and negative poles of the DC charging station. X .

10. The power conversion device according to claim 1, characterized in that: The power conversion circuit includes: a coil L2, a capacitor C 2A , capacitor C 2B , capacitor C F 、Inductance L FA 、Inductance L FB , switch S1, switch S2, switch S3, switch S4, capacitor C0; One end of coil L2 is connected to capacitor C 2A One end, capacitor C 2A The other end is connected to capacitor C F One end, inductor L FA One end and the positive pole of the DC charging stand, inductor L FA The other end is connected to one end of switch S1 and one end of switch S4 respectively, and the other end of switch S1 is connected to one end of switch S2, one end of capacitor C0 and the positive electrode of the rechargeable battery respectively; The other end of coil L2 is connected to capacitor C 2B One end, capacitor C 2B The other end is connected to capacitor C F The other end, the negative pole of the DC charging station and the inductor L FB One end, inductor L FB The other end is respectively connected to the other end of switch S2 and one end of switch S3, and the other end of switch S3 is respectively connected to the other end of switch S4, the other end of capacitor C0 and the negative electrode of the rechargeable battery.

11. The power conversion device according to claim 10, characterized in that: The power conversion circuit also includes: a switch Q1 and an input capacitor C X ; The capacitor C 2A A switch Q1 is connected between the other end and the positive pole of the DC charging station; Connect an input capacitor C between the positive pole of the DC charging base and the other end of switch S3. X .

12. The power conversion device according to claim 8, characterized in that: The DC charging station positive electrode includes a contact port P1 and a contact port P2; The contact port P1 and the capacitor C 2A The other end is connected to the contact port P2 and the capacitor C 2B The other end is connected.

13. The power conversion device according to claim 8, characterized in that: The DC charging seat positive electrode includes a contact port P1, a contact port P2 and a contact port P3, and the power conversion device also includes: an input capacitor C X ; The contact port P1 and the capacitor C 2A The other end is connected to the contact port P2 and the capacitor C 2B The other end is connected to the input capacitor C between the contact port P3 and the negative electrode of the DC charging base X .

14. The power conversion device according to claim 8, characterized in that: The power conversion circuit further includes: a switch Q1 and a switch Q2; The positive electrode of the DC charging base and the capacitor C 2B The other end is connected with switch Q1; The positive electrode of the DC charging base and the capacitor C 2A The other end is connected with switch Q2.

15. The power conversion device according to claim 6, characterized in that: The power conversion circuit further includes: a switch Q1, a switch Q2 and a switch Q3; The positive electrode of the DC charging base and the capacitor C 2B The other end is connected with switch Q1; The positive electrode of the DC charging base and the capacitor C 2A The other end is connected with switch Q2; A switch Q3 is connected between the positive electrode of the DC charging base and the other end of the switch S1.

16. The power conversion device according to claim 14 or 15, characterized in that: The power conversion circuit also includes: an input capacitor C X ; Connect the input capacitor C between the positive pole of the DC charging base and the negative pole of the DC charging base. X .

17. The power conversion device according to claim 1, characterized in that: The power conversion circuit includes: a coil L2, a capacitor C 2A , capacitor C 2B , capacitor C F 、Inductance L FA 、Inductance L FB , switch S1, switch S2, switch S3, switch S4, switch S5, switch S6, switch Q1, capacitor C0; One end of coil L2 is connected to capacitor C 2A One end, capacitor C 2A The other end is connected to capacitor C F One end, inductor L FA One end, inductor L FB One end and one end of switch Q1, inductor L FA The other end is connected to the switch S1 and the switch S6 respectively. The inductor L FB The other end is connected to one end of switch S2 and one end of switch S5 respectively, and the other end of switch S1 is connected to the other end of switch S2, one end of switch S3, one end of capacitor C0 and the positive electrode of the rechargeable battery respectively; The other end of coil L2 is connected to capacitor C 2B One end, capacitor C 2B The other end is connected to capacitor C F the other end, the other end of switch S3 and one end of switch S4; The positive pole of the DC charging base is connected to the other end of the switch Q1; The negative pole of the DC charging base is respectively connected to the other end of the switch S6, the other end of the switch S5, the other end of the switch S4, the other end of the capacitor C0 and the negative pole of the rechargeable battery.

18. The power conversion device according to claim 17, characterized in that: The power conversion circuit further includes: a switch Q2; The switch Q2 is connected between the other end of the switch S1 and the positive electrode of the DC charging base.

19. The power conversion device according to claim 17 or 18, characterized in that: The power conversion circuit also includes: an input capacitor C X ; Connect the input capacitor C between the positive pole of the DC charging base and the negative pole of the DC charging base. X .

20. The power conversion device according to claim 17, 18 or 19, characterized in that: The power conversion circuit also includes: a switch Q3 and an inductor L FC ; The capacitor C 2B The inductor L is connected between the other end and the other end of the switch S3 and one end of the switch S4. FC ; The inductance L FC Close to capacitor C 2B The switch Q3 is connected between one end of the other end and the positive electrode of the DC charging base.

21. A vehicle charging system, characterized in that: It comprises the power conversion device and controller as described in any one of claims 1-20, wherein the controller is connected to the power conversion device and is used to control the on and off of the switch in the power conversion device to perform conversion between wireless charging and wired DC charging.

Images