Bidirectional charging and DCDC integrated circuit structure

Abstract

The utility model discloses a bidirectional charging and DCDC integrated circuit structure, which comprises a two-stage EMI filtering input module, a bridgeless totem-pole PFC module, an LLC module, a phase-shifted full-bridge DCDC module and a two-stage EMI filtering output module, and is characterized in that alternating current is connected with the input end of the bridgeless totem-pole PFC module through the two-stage EMI filtering input module; the output end of the bridgeless totem pole PFC module is connected with a first winding of a magnetic integrated main transformer in the LLC module, the output end of the LLC module is connected with the large battery pack through the two-stage EMI filter output module, and a second winding and a third winding of the magnetic integrated main transformer in the LLC module are connected with the phase-shifted full-bridge DCDC module; the LLC module is a double-pole single-throw LLC module, and a resonant inductance coil and a resonant capacitor are adjusted through a double-pole single-throw switch, so that the gain range is adjusted, and the resonant frequency is maintained.

Description

Technical Field

[0001] The utility model relates to the technical field of on-board chargers for new energy vehicles, and in particular to a circuit structure for widening output voltage type bidirectional charging and DCDC fusion. Background Art

[0002] At present, mainstream on-board chargers and DCDC products for new energy vehicles have their own independent topologies. Usually, bidirectional inverters are mostly CLLC, unidirectional charging is mostly LLC, and the DCDC function part usually uses a phase-shifted full bridge. Since these two products are indispensable in new energy vehicles, they are usually combined as much as possible to form a two-in-one or all-in-one product.

[0003] However, in the market, two transformers are generally used to complete each power part. The electrical characteristics of CLLC and LLC topologies determine that their output range cannot be wide, and the vehicle has to strictly limit the working range of the battery pack to define the platform characteristics. There are also some products in the market that increase the output range by parallelizing two outputs in the back stage, but the space is too large and the power density is low.

[0004] Therefore, the applicant has found a solution to the above-mentioned problem through beneficial exploration and research, and the technical solution to be introduced below is produced in this context. Utility Model Content

[0005] The technical problem to be solved by the utility model is: to provide a circuit structure of bidirectional charging and DCDC fusion with a widened output voltage type, which improves the output range, enhances the power density, and improves the integration, in view of the shortcomings of the prior art.

[0006] The technical problem to be solved by the present invention can be achieved by adopting the following technical solutions:

[0007] A circuit structure integrating bidirectional charging and DCDC, comprising a two-stage EMI filter input module, a bridgeless totem pole PFC module, an LLC module, a phase-shifted full-bridge DCDC module and a two-stage EMI filter output module, wherein the alternating current is connected to the input end of the bridgeless totem pole PFC module through the two-stage EMI filter input module, the output end of the bridgeless totem pole PFC module is connected to the first winding of the magnetically integrated main transformer in the LLC module, the output end of the LLC module is connected to a large battery pack through the two-stage EMI filter output module, and the second and third windings of the magnetically integrated main transformer in the LLC module are connected to the phase-shifted full-bridge DCDC module; characterized in that:

[0008] The LLC module is a double-pole single-throw LLC module, which adjusts the resonant inductor and the resonant capacitor through a double-pole single-throw switch to adjust the gain range and maintain the resonant frequency.

[0009] In a preferred embodiment of the utility model, the bridgeless totem pole PFC module includes a first inductor, a first capacitor, and first, second, third, and fourth MOS transistors; one end of the first MOS transistor, one end of the second MOS transistor, and one end of the first capacitor are connected in parallel, the other end of the first MOS transistor and the other end of the second MOS transistor are correspondingly connected to one end of the third MOS transistor and one end of the fourth MOS transistor, the other end of the third MOS transistor, the other end of the fourth MOS transistor, and the other end of the first capacitor are connected in parallel and then grounded, one end of the first inductor is connected to one end of the two-stage EMI filter input module, and the other end is connected to the common connection end between the second MOS transistor and the fourth MOS transistor, and the common connection end between the first MOS transistor and the third MOS transistor is connected to the other end of the two-stage EMI filter input module.

[0010] In a preferred embodiment of the utility model, the double-pole single-throw LLC module includes fifth, sixth, seventh, eighth, ninth, tenth, eleventh, and twelfth MOS tubes, first and second resonant inductors, first and second resonant capacitors, a double-pole single-throw relay, a second capacitor, and a magnetic integrated main transformer;

[0011] One end of the fifth MOS tube and one end of the sixth MOS tube are connected in parallel and then connected to one end of the first capacitor, the other end of the fifth MOS tube and the other end of the sixth MOS tube are connected to one end of the seventh MOS tube and one end of the eighth MOS tube respectively, and the other end of the seventh MOS tube and the other end of the eighth MOS tube are connected in parallel and then connected to the other end of the first capacitor;

[0012] One end of the first resonant inductor is connected in parallel with one end of one side of the double-pole single-throw switch of the double-pole single-throw relay and then connected between the sixth MOS tube and the eighth MOS tube, and the other end of the first resonant inductor is connected in parallel with one end of the second resonant inductor and then connected to one end of the first winding of the magnetic integrated main transformer, the other end of one side of the double-pole single-throw switch of the double-pole single-throw relay is connected in parallel with one end of the first resonant capacitor and then connected between the fifth MOS tube and the seventh MOS tube, the other end of the first resonant capacitor is connected in parallel with one end of the second resonant capacitor and then connected to the other end of the first winding of the magnetic integrated main transformer, and the two ends of the other side of the double-pole single-throw switch of the double-pole single-throw relay are respectively connected to the other end of the second resonant inductor and the other end of the second resonant capacitor;

[0013] One end of the ninth MOS tube and one end of the eleventh MOS tube are connected in parallel and then connected to one end of the second winding of the magnetic integrated main transformer; the other end of the ninth MOS tube, one end of the tenth MOS tube and one end of the second capacitor are connected in parallel and then connected to one end of the two-stage EMI filter output module; the other end of the tenth MOS tube and one end of the twelfth MOS tube are connected in parallel and then connected to the other end of the second winding of the magnetic integrated main transformer; the other end of the eleventh MOS tube, the other end of the twelfth MOS tube and the other end of the second capacitor are connected in parallel and then connected to the other end of the two-stage EMI filter output module and grounded.

[0014] In a preferred embodiment of the present utility model, the phase-shifted full-bridge DCDC module includes a thirteenth MOS tube, a second inductor, a third capacitor, a resistor, and first, second, third, and fourth diodes, and also includes the ninth, tenth, eleventh, and twelfth MOS tubes and the second capacitor;

[0015] One end of the ninth MOS tube and one end of the eleventh MOS tube are connected in parallel and then connected to one end of the second winding of the magnetic integrated main transformer; the other end of the ninth MOS tube, one end of the tenth MOS tube and one end of the second capacitor are connected in parallel and then connected to one end of the two-stage EMI filter output module; the other end of the tenth MOS tube and one end of the twelfth MOS tube are connected in parallel and then connected to the other end of the second winding of the magnetic integrated main transformer; the other end of the eleventh MOS tube, the other end of the twelfth MOS tube and the other end of the second capacitor are connected in parallel and then connected to the other end of the two-stage EMI filter output module and grounded;

[0016] The positive pole of the first diode and the negative pole of the third diode are connected in parallel and connected to one end of the third winding of the magnetic integrated main transformer. The negative pole of the first diode and the negative pole of the second diode are connected in parallel and connected to one end of the second inductor. The other end of the second inductor is connected in parallel to one end of the third capacitor and connected to the positive pole of the small battery pack. The positive pole of the second diode and the negative pole of the fourth diode are connected in parallel and connected to the other end of the third winding of the magnetic integrated main transformer. The positive pole of the third diode and the positive pole of the fourth diode are connected in parallel and connected to one end of the thirteenth MOS tube. The other end of the thirteenth MOS tube is connected to the other end of the third capacitor through the resistor and connected to the negative pole of the small battery pack and then grounded.

[0017] In a preferred embodiment of the present invention, the two-stage EMI filter input module is a two-stage EMI filter, and the two-stage EMI filter output module is a two-stage EMI filter.

[0018] Due to the adoption of the above technical solution, the beneficial effects of the utility model are:

[0019] 1. The main transformer of the utility model is deeply integrated, the parameters of the main transformer are fixed, and the double-pole single-throw relay in the double-pole single-throw LLC module is used to adjust the resonant inductance and resonant capacitance, which can adjust the gain range and maintain the resonant frequency, thereby better compatibility with various battery pack platforms of real vehicles;

[0020] 2. The utility model adopts a fusion topology, a common magnetic core of the main transformer, deep integration, LLC rear-stage output and DCDC input fusion, and supports wide-range charging and inverter bidirectional operation. It also supports DC / DC function, reduces power tubes, reduces data by half, is deeply integrated, and has a simple magnetic component switching circuit, which reduces process difficulty, reduces product volume, and improves power density. BRIEF DESCRIPTION OF THE DRAWINGS

[0021] In order to more clearly illustrate the embodiments of the utility model or the technical solutions in the prior art, the drawings required for use in the embodiments or the description of the prior art will be briefly introduced below. Obviously, the drawings described below are only some embodiments of the utility model. For ordinary technicians in this field, other drawings can be obtained based on these drawings without paying creative work.

[0022] Figure 1 It is a structural schematic diagram of the circuit structure of bidirectional charging and DCDC fusion of the utility model (K1 is in the disconnected state).

[0023] Figure 2 It is a structural schematic diagram of the circuit structure of bidirectional charging and DCDC fusion of the utility model (K1 is in a closed state).

[0024] Figure 3 It is a separate working schematic diagram of the phase-shifted full-bridge DCDC module of the utility model.

[0025] Figure 4 The utility model discloses a double-pole single-throw widened output working flow chart. DETAILED DESCRIPTION

[0026] In order to make the technical means, creative features, objectives and effects achieved by the present invention easy to understand, the present invention is further described below with reference to specific illustrations.

[0027] See also Figure 1 and Figure 2The figure shows a circuit structure of bidirectional charging and DCDC fusion, including a two-stage EMI filter input module 100, a bridgeless totem pole PFC module 200, an LLC module 300, a phase-shifted full-bridge DCDC module 400 and a two-stage EMI filter output module 500. The AC power 10 is connected to the input end of the bridgeless totem pole PFC module 200 through the two-stage EMI filter input module 100, the output end of the bridgeless totem pole PFC module 200 is connected to the first winding of the magnetic integrated main transformer in the LLC module 300, the output end of the LLC module 300 is connected to the large battery pack 20a through the two-stage EMI filter output module 500, and the second and third windings of the magnetic integrated main transformer in the LLC module 300 are connected to the phase-shifted full-bridge DCDC module 400. Among them, the two-stage EMI filter input module 100 preferably adopts a two-stage EMI filter, and the two-stage EMI filter output module 500 preferably adopts a two-stage EMI filter.

[0028] The bridgeless totem pole PFC module 200 includes an inductor coil Lf, a capacitor C1, and MOS transistors S1, S2, S3, and S4. One end of the MOS transistor S1, one end of the MOS transistor S2, and one end of the capacitor C1 are connected in parallel, and the other end of the MOS transistor S1 and the other end of the MOS transistor S2 are connected to one end of the MOS transistor S3 and one end of the MOS transistor S4 respectively, and the other end of the MOS transistor S3, the other end of the MOS transistor S4, and the other end of the capacitor C1 are connected in parallel and then grounded, one end of the inductor coil Lf is connected to one end of the two-stage EMI filter input module 100, and the other end thereof is connected to the common connection end between the MOS transistor S2 and the MOS transistor S4, and the common connection end between the MOS transistor S1 and the MOS transistor S3 is connected to the other end of the two-stage EMI filter input module 100.

[0029] The LLC module 300 adopts a double-pole single-throw LLC module, which adjusts the resonant inductor and resonant capacitor through a double-pole single-throw switch to adjust the gain range and maintain the resonant frequency, so as to better be compatible with various battery pack platforms of the actual vehicle. Specifically, the double-pole single-throw LLC module includes MOS tubes S5, S6, S7, S8, S9, S10, S11, S12, resonant inductors Lr1, Lr2, resonant capacitors Cr1, Cr2, double-pole single-throw relays, capacitors C2 and magnetic integrated main transformers Lm.

[0030] One end of the MOS transistor S5 and one end of the MOS transistor S6 are connected in parallel and then connected to one end of the capacitor C1. The other ends of the MOS transistor S5 and the other ends of the MOS transistor S6 are connected to one end of the MOS transistor S7 and one end of the MOS transistor S8 respectively. The other ends of the MOS transistor S7 and the other ends of the MOS transistor S8 are connected in parallel and then connected to the other end of the capacitor C1.

[0031] One end of the resonant inductor Lr1 is connected in parallel with one end of one side of the double-pole single-throw switch K1 of the double-pole single-throw relay and then connected between the MOS tube S6 and the MOS tube S8. The other end of the resonant inductor Lr1 is connected in parallel with one end of the resonant inductor Lr2 and then connected to one end of the first winding of the magnetic integrated main transformer Lm. The other end of the double-pole single-throw switch K1 of the double-pole single-throw relay is connected in parallel with one end of the resonant capacitor Cr1 and then connected between the MOS tube S5 and the MOS tube S7. The other end of the resonant capacitor Cr1 is connected in parallel with one end of the resonant capacitor Cr2 and then connected to the other end of the first winding of the magnetic integrated main transformer Lm. The two ends of the other side of the double-pole single-throw switch K1 of the double-pole single-throw relay are respectively connected to the other end of the resonant inductor Lr2 and the other end of the resonant capacitor Cr2.

[0032] One end of the MOS tube S9 and one end of the MOS tube S11 are connected in parallel and connected to one end of the second winding of the magnetic integrated main transformer Lm. The other end of the MOS tube S9, one end of the MOS tube S10 and one end of the capacitor C2 are connected in parallel and connected to one end of the two-stage EMI filter output module 500. The other end of the MOS tube S10 and one end of the MOS tube S12 are connected in parallel and connected to the other end of the second winding of the magnetic integrated main transformer Lm. The other end of the MOS tube S11, the other end of the MOS tube S12 and the other end of the capacitor C2 are connected in parallel and connected to the other end of the two-stage EMI filter output module 500 and grounded.

[0033] See also Figure 3 Combined with Figure 1 and Figure 2 The phase-shifted full-bridge DCDC module 400 includes a MOS tube S13, an inductor Lo, a capacitor C3, a resistor R, and diodes D1, D2, D3, and D4, and also includes MOS tubes S9, S10, S11, S12 and a capacitor C2.

[0034] One end of the MOS tube S9 and one end of the MOS tube S11 are connected in parallel and connected to one end of the second winding of the magnetic integrated main transformer Lm. The other end of the MOS tube S9, one end of the MOS tube S10 and one end of the capacitor C2 are connected in parallel and connected to one end of the two-stage EMI filter output module 500. The other end of the MOS tube S10 and one end of the MOS tube S12 are connected in parallel and connected to the other end of the second winding of the magnetic integrated main transformer Lm. The other end of the MOS tube S11, the other end of the MOS tube S12 and the other end of the capacitor C2 are connected in parallel and connected to the other end of the two-stage EMI filter output module 500 and grounded.

[0035] The positive electrode of diode D1 and the negative electrode of diode D3 are connected in parallel and connected to one end of the third winding of the magnetic integrated main transformer Lm. The negative electrode of diode D1 and the negative electrode of diode D2 are connected in parallel and connected to one end of the inductor Lo. The other end of the inductor Lo is connected in parallel to one end of the capacitor C3 and then connected to the positive electrode of the small battery pack 20b. The positive electrode of diode D2 and the negative electrode of diode D4 are connected in parallel and connected to the other end of the third winding of the magnetic integrated main transformer Lm. The positive electrode of diode D3 and the positive electrode of diode D4 are connected in parallel and connected to one end of the MOS tube S13. The other end of the MOS tube S13 is connected to the other end of the capacitor C3 through the resistor R and is connected to the negative electrode of the small battery pack 20b and then grounded.

[0036] The phase-shifted full-bridge DCDC module 400 can control the on or off of the MOS tube S13 according to whether the DCDC operation needs to be enabled; the control parameters required to achieve a given voltage and a given current are calculated through the phase-shifted full-bridge control algorithm, and the PWM frequency and duty cycle are controlled by the MCU main chip through the PWM control principle and output to the MOS tubes S9, S10, S11, and S12, and a stable voltage output or current output is obtained by controlling the current loop or the voltage loop (depending on the situation).

[0037] The utility model adopts a fusion topology, a common magnetic core of the main transformer, deep integration, LLC rear-stage output and DCDC input fusion, and supports wide-range charging and inverter bidirectional operation. It also supports DC / DC function, reduces power tubes, reduces data by half, is deeply integrated, and has a simple magnetic component switching circuit, which reduces process difficulty, reduces product volume, and improves power density.

[0038] See also Figure 4 , the figure shows a control method of a circuit structure integrating bidirectional charging and DCDC, including the following steps:

[0039] 1. The circuit is awakened by low voltage and powered on by high voltage after self-test. The double-pole single-throw switch K1 of the double-pole single-throw relay is in the disconnected state by default;

[0040] 2. When charging is required, collect the voltage value of the battery pack and make the following judgments based on the voltage value of the battery pack:

[0041] a. When the battery pack voltage is in the relatively low range of 150V-235V, the double-pole single-throw switch K1 of the double-pole single-throw relay continues to maintain the disconnected state, such as Figure 1 As shown, at this time, only the resonant inductor Lr1, the resonant capacitor Cr1 and the magnetic integrated main transformer Lm are involved in the work to maintain low-voltage charging. At this time, charging starts and the voltage of the battery pack slowly increases; otherwise, execute step b;

[0042] b. Determine whether the voltage of the battery pack is within 230V-510V. If it is, it indicates that the battery pack is in the high voltage range. The double-pole single-throw switch K1 of the double-pole single-throw relay is switched to the closed state. Figure 2 As shown, at this time, the resonant inductors Lr1, Lr2, the resonant capacitors Cr1, Cr2 and the magnetic integrated main transformer Lm are working at the same time, the resonant equivalent inductance of the resonant cavity is reduced, and the resonant capacitance is increased until the battery pack is fully charged and the charging is terminated.

[0043] The above shows and describes the basic principle and main features of the utility model and the advantages of the utility model. Those skilled in the art should understand that the utility model is not limited by the above embodiments. The above embodiments and descriptions are only for explaining the principle of the utility model. Without departing from the spirit and scope of the utility model, the utility model may have various changes and improvements, which fall within the scope of the utility model to be protected. The scope of protection claimed by the utility model is defined by the attached claims and their equivalents.

Claims

1. A circuit structure integrating bidirectional charging and DCDC, comprising a two-stage EMI filter input module, a bridgeless totem pole PFC module, an LLC module, a phase-shifted full-bridge DCDC module and a two-stage EMI filter output module, wherein the AC power is connected to the input end of the bridgeless totem pole PFC module through the two-stage EMI filter input module, the output end of the bridgeless totem pole PFC module is connected to the first winding of the magnetically integrated main transformer in the LLC module, the output end of the LLC module is connected to a large battery pack through the two-stage EMI filter output module, and the second and third windings of the magnetically integrated main transformer in the LLC module are connected to the phase-shifted full-bridge DCDC module; characterized in that: The LLC module is a double-pole single-throw LLC module, which adjusts the resonant inductor and the resonant capacitor through a double-pole single-throw switch to adjust the gain range and maintain the resonant frequency.

2. The circuit structure of bidirectional charging and DCDC fusion as claimed in claim 1, characterized in that: The bridgeless totem pole PFC module includes a first inductor, a first capacitor, and first, second, third, and fourth MOS transistors; one end of the first MOS transistor, one end of the second MOS transistor, and one end of the first capacitor are connected in parallel, the other end of the first MOS transistor and the other end of the second MOS transistor are correspondingly connected to one end of the third MOS transistor and one end of the fourth MOS transistor, the other end of the third MOS transistor, the other end of the fourth MOS transistor, and the other end of the first capacitor are connected in parallel and then grounded, one end of the first inductor is connected to one end of the two-stage EMI filter input module, the other end of the first inductor is connected to a common connection end between the second MOS transistor and the fourth MOS transistor, and the common connection end between the first MOS transistor and the third MOS transistor is connected to the other end of the two-stage EMI filter input module.

3. The circuit structure of bidirectional charging and DCDC fusion as claimed in claim 2, characterized in that: The double-pole single-throw LLC module includes fifth, sixth, seventh, eighth, ninth, tenth, eleventh and twelfth MOS tubes, first and second resonant inductors, first and second resonant capacitors, a double-pole single-throw relay, a second capacitor and a magnetic integrated main transformer; One end of the fifth MOS tube and one end of the sixth MOS tube are connected in parallel and then connected to one end of the first capacitor, the other end of the fifth MOS tube and the other end of the sixth MOS tube are connected to one end of the seventh MOS tube and one end of the eighth MOS tube respectively, and the other end of the seventh MOS tube and the other end of the eighth MOS tube are connected in parallel and then connected to the other end of the first capacitor; One end of the first resonant inductor is connected in parallel with one end of one side of the double-pole single-throw switch of the double-pole single-throw relay and then connected between the sixth MOS tube and the eighth MOS tube, and the other end of the first resonant inductor is connected in parallel with one end of the second resonant inductor and then connected to one end of the first winding of the magnetic integrated main transformer, the other end of one side of the double-pole single-throw switch of the double-pole single-throw relay is connected in parallel with one end of the first resonant capacitor and then connected between the fifth MOS tube and the seventh MOS tube, the other end of the first resonant capacitor is connected in parallel with one end of the second resonant capacitor and then connected to the other end of the first winding of the magnetic integrated main transformer, and the two ends of the other side of the double-pole single-throw switch of the double-pole single-throw relay are respectively connected to the other end of the second resonant inductor and the other end of the second resonant capacitor; One end of the ninth MOS tube and one end of the eleventh MOS tube are connected in parallel and then connected to one end of the second winding of the magnetic integrated main transformer; the other end of the ninth MOS tube, one end of the tenth MOS tube and one end of the second capacitor are connected in parallel and then connected to one end of the two-stage EMI filter output module; the other end of the tenth MOS tube and one end of the twelfth MOS tube are connected in parallel and then connected to the other end of the second winding of the magnetic integrated main transformer; the other end of the eleventh MOS tube, the other end of the twelfth MOS tube and the other end of the second capacitor are connected in parallel and then connected to the other end of the two-stage EMI filter output module and grounded.

4. The circuit structure of bidirectional charging and DCDC fusion as claimed in claim 3, characterized in that: The phase-shifted full-bridge DCDC module includes a thirteenth MOS tube, a second inductor, a third capacitor, a resistor, and first, second, third, and fourth diodes, and also includes the ninth, tenth, eleventh, and twelfth MOS tubes and the second capacitor; The positive pole of the first diode and the negative pole of the third diode are connected in parallel and connected to one end of the third winding of the magnetic integrated main transformer. The negative pole of the first diode and the negative pole of the second diode are connected in parallel and connected to one end of the second inductor. The other end of the second inductor is connected in parallel to one end of the third capacitor and connected to the positive pole of the small battery pack. The positive pole of the second diode and the negative pole of the fourth diode are connected in parallel and connected to the other end of the third winding of the magnetic integrated main transformer. The positive pole of the third diode and the positive pole of the fourth diode are connected in parallel and connected to one end of the thirteenth MOS tube. The other end of the thirteenth MOS tube is connected to the other end of the third capacitor through the resistor and connected to the negative pole of the small battery pack and then grounded.

5. The circuit structure of bidirectional charging and DCDC fusion as claimed in claim 1, characterized in that: The two-stage EMI filter input module is a two-stage EMI filter, and the two-stage EMI filter output module is a two-stage EMI filter.

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