CN210807100U

CN210807100U - Power transmission circuit

Info

Publication number: CN210807100U
Application number: CN201921775401.9U
Authority: CN
Inventors: 凌和平; 黄伟; 潘华; 骆孝龙; 刘建斌
Original assignee: BYD Co Ltd; Changsha BYD Automobile Co Ltd
Current assignee: BYD Co Ltd; Changsha BYD Automobile Co Ltd
Priority date: 2019-10-18
Filing date: 2019-10-18
Publication date: 2020-06-19
Anticipated expiration: 2029-10-18

Abstract

The embodiment of the utility model provides a power transmission circuit, including first conversion module, high-voltage module and low-voltage module connected with the first conversion module respectively, and control module; first conversion module includes first bridge type switch circuit, high pressure module includes high voltage bridge type switch circuit, low pressure module includes low voltage bridge type switch circuit, first bridge type switch circuit, high voltage bridge type switch circuit and low voltage bridge type switch circuit are connected through coil coupling each other, control module respectively with first bridge type switch circuit, high voltage bridge type switch circuit and low voltage bridge type switch circuit connect. The utility model discloses not only can reach the purpose that promotes power density, subtracts heavy and reduce the cost, owing to reduced electronic components's quantity among the power conversion circuit, reduced the probability that electronic components became invalid, also can promote vehicle power supply's reliability.

Description

Power transmission circuit

Technical Field

The utility model relates to a power transmission technical field especially relates to a power transmission circuit.

Background

With the increasing consumption of energy, the energy-saving requirement on the running equipment is also higher and higher.

Especially in the automotive field, kinetic energy is increasingly being supplied from fossil fuels to renewable energy sources. The power is important. After using electric energy as power energy of the vehicle, the electric energy is needed to provide working electric energy for various devices in the vehicle, such as vehicle lights, navigation, control terminals, and the like, in addition to providing the vehicle with continuous driving. Different devices require different electric energy, and therefore different power supply devices and electric energy conversion devices are required to provide working electric energy for the devices.

The vehicle-mounted charger (OBC module), the low-voltage direct-current power supply (DC module) and the high-voltage direct-current power supply (DC module) are key components required by charging and supplying power for the electric automobile. Currently, OBC modules and DC modules employ separate functional sub-circuit/component connections that are low power density, low efficiency and high cost. And most of the integrated physical structures or the integrated local shared circuits need additional parts, the number of devices for realizing local functions is increased, the reliability of a power supply is reduced, the integrated circuits of all the parts are large in size, the whole weight is heavy, the circuit transmission efficiency is low, the electric energy consumption is high, and the operation and the control of technical personnel are difficult.

SUMMERY OF THE UTILITY MODEL

In view of the above, embodiments of the present invention are proposed in order to provide a power transmission circuit that overcomes or at least partially solves the above mentioned problems.

In order to solve the above problem, an embodiment of the present invention discloses a power transmission circuit, which includes a first conversion module, a high voltage module and a low voltage module respectively connected to the first conversion module, and a control module;

the first conversion module comprises a first bridge type switch circuit, the high-voltage module comprises a high-voltage bridge type switch circuit, the low-voltage module comprises a low-voltage bridge type switch circuit, the first bridge type switch circuit, the high-voltage bridge type switch circuit and the low-voltage bridge type switch circuit are coupled and connected with each other through coils, and the control module is respectively connected with the first bridge type switch circuit, the high-voltage bridge type switch circuit and the low-voltage bridge type switch circuit;

the control module is used for controlling the high-voltage bridge type switching circuit to be in a full-bridge rectification topology switching mode and controlling the low-voltage bridge type switching circuit to be in a center-tap rectification topology switching mode when the first bridge type switching circuit is in the full-bridge switching module, so that the first switching is used for respectively charging the high-voltage module and the low-voltage module;

or, the controller is configured to control the first bridge switching circuit to be in an off mode, control the high-voltage bridge switching circuit to be in a half-bridge rectification topology switching mode, and control the low-voltage bridge switching circuit to be in a center-tap rectification topology switching mode, so that the high-voltage module charges the low-voltage module separately.

Optionally, the control module further comprises:

and the high-voltage module is used for controlling the high-voltage bridge type switching circuit to be in the full-bridge topology switching mode and controlling the low-voltage bridge type switching circuit to be in the center tap rectification topology switching mode when the first bridge type switching circuit is in the full-bridge rectification topology switching mode, so that the high-voltage module respectively charges the first conversion module and the low-voltage module.

Optionally, the first conversion module further includes an ac power supply, a PFC circuit connected to the ac current, an inductor L1 and a capacitor C4 connected to the first dc terminal and the second dc terminal of the power bridge circuit, respectively, and a power coil connected in series to the first terminal of the inductor L1 and the first terminal of the capacitor C4, respectively, and the PFC circuit is connected to the first ac terminal and the second ac terminal of the power bridge circuit.

Optionally, the first bridge switching circuit comprises: the MOS transistors comprise 4 MOS transistors which are respectively Q1, Q2, Q3 and Q4, wherein the Q1 is connected with the Q3 in series, the Q2 is connected with the Q4 in series, the Q1 is connected with the Q3, the Q2 is connected with the Q4 in parallel, the Q1, the Q2, the Q3 and the Q4 are connected into a bridge structure, the Q1 is connected with the connection end of the Q3 and the second end of an inductor L1, and the Q2 is connected with the connection end of the Q4 and the second end of a capacitor C4.

Optionally, the high voltage module further includes a high voltage battery, a filter capacitor C2 connected in parallel with the high voltage battery, an inductor L2 and a capacitor C5 connected to two ends of the high voltage bridge switch circuit respectively, and a high voltage coil connected in series to a first end of the inductor L2 and a first end of the capacitor C5 respectively, wherein the high voltage bridge switch circuit is connected to two ends of the filter capacitor C2 respectively.

Optionally, the high voltage bridge switching circuit comprises: 4 MOS tubes, Q5, Q6, Q7 and Q8 respectively, wherein the Q5 is connected with the Q7 in series, the Q6 is connected with the Q8 in series, the Q5 is connected with the Q7 and the Q6 is connected with the Q8 in parallel, so that the Q5, the Q6, the Q7 and the Q8 are connected into a bridge structure, the Q5 is connected with the connection end of the Q7 and the second end of an inductor L2, and the Q6 is connected with the connection end of the Q8 and the second end of a capacitor C5.

Optionally, the controlling the high-voltage bridge switching circuit in a half-bridge rectification topology switching mode includes:

the Q5 and the Q7 are controlled to be in a switching mode of alternating conduction, the Q8 is controlled to be in a switching mode of constant conduction, and the Q6 is controlled to be in a switching mode of constant disconnection.

the Q6 and the Q8 are controlled to be in a switching mode of alternating conduction, the Q7 is controlled to be in a switching mode of constant conduction, and the Q5 is controlled to be in a switching mode of constant disconnection.

Optionally, the low voltage module further includes a low voltage battery, a filter capacitor C3 connected in parallel with the low voltage battery, and low voltage coils respectively connected to two ends of the low voltage bridge switch circuit, and the low voltage bridge switch circuit is connected to the filter capacitor C3.

Optionally, the low-voltage bridge switch circuit includes two MOS transistors, Q9 and Q10, two ends of the low-voltage coil are connected to the first end of Q9 and the first end of Q10, the second end of Q9 is connected to the positive terminal of the filter capacitor C3, the second end of Q10 is connected to the positive terminal of the filter capacitor C3, and the negative terminal of the filter capacitor C3 is connected to the midpoint of the low-voltage coil.

Optionally, the low-voltage bridge switch circuit includes two unidirectional diodes, D9 and D10, two ends of the low-voltage coil are connected to the positive terminals of D9 and D10, the negative terminal of D9 is connected to the positive terminal of the filter capacitor C3, the negative terminal of D10 is connected to the positive terminal of the filter capacitor C3, and the negative terminal of the filter capacitor C3 is connected to the midpoint of the low-voltage coil.

The embodiment of the utility model provides a include following advantage:

the utility model can not only achieve the purposes of improving power density, reducing weight and reducing cost, but also improve the reliability of the vehicle-mounted power supply as the number of electronic components in the power conversion circuit is reduced, thereby reducing the failure probability of the electronic components; meanwhile, the number of elements in a switching state and switching loss can be reduced, the electric energy transmission efficiency is improved, and the power supply efficiency for supplying power to the low-voltage battery in a light-load state is improved.

Drawings

Fig. 1 is a schematic structural diagram of one embodiment of the power transmission circuit of the present invention

Fig. 2 is a schematic structural diagram of one embodiment of a power transmission circuit of the present invention;

fig. 3 is a schematic structural diagram of one embodiment of a power transmission circuit of the present invention;

fig. 4 is a schematic structural diagram of one embodiment of a power transmission circuit of the present invention;

fig. 5 is a schematic structural diagram of one embodiment of a power transmission circuit of the present invention;

fig. 6 is a schematic structural diagram of one embodiment of the power transmission circuit of the present invention.

Detailed Description

In order to make the above objects, features and advantages of the present invention more comprehensible, the present invention is described in detail with reference to the accompanying drawings and the detailed description.

Referring to fig. 1, a schematic structural diagram of one embodiment of the power transmission circuit of the present invention is shown, and specifically, the power transmission circuit may include the following modules: the high-voltage module and the low-voltage module are connected with each other, the first conversion module 1 is connected with the high-voltage module and the low-voltage module respectively, the high-voltage module is connected with the low-voltage module, and the control module can be connected with the first conversion module, the high-voltage module and the low-voltage module respectively. The control module is used for respectively controlling the on and off of the first conversion module, the high-voltage module and the low-voltage module. The first conversion module can respectively and independently supply power to the high-voltage module and the low-voltage module, or the first conversion module simultaneously supplies power to the high-voltage module or the low-voltage module, or the high-voltage module respectively supplies power to the low-voltage module and the first conversion module, or the high-voltage module independently supplies power to the low-voltage module, and the like.

In this embodiment, the control module may control the first conversion module to be switched on with the high voltage module, and the low voltage module to be switched off, so that the first conversion module supplies power to the high voltage module or the high voltage module supplies power to the first conversion module; the first conversion module, the high-voltage module and the low-voltage module can also be controlled to be conducted, so that the first conversion module respectively supplies power to the high-voltage module and the low-voltage module, or the high-voltage module respectively supplies power to the first conversion module and the low-voltage module; the first conversion module can also be controlled to be closed, and the high-voltage module is communicated with the low-voltage module, so that the high-voltage module supplies power to the low-voltage module.

Referring to fig. 2, a schematic structural diagram of one embodiment of the Power transmission circuit of the present invention is shown, wherein the first conversion module includes an AC Power supply AC, a filter capacitor C1 connected in parallel with the AC Power supply AC, and a Power Factor Correction circuit (PFC circuit for short) connected in parallel with the AC Power supply AC. And the high-voltage module comprises a high-voltage battery and a filter capacitor C2 connected with the high-voltage battery in parallel. The low-voltage module comprises a low-voltage battery and a filter capacitor C3 connected with the low-voltage battery in parallel. The high-voltage module and the low-voltage module can be connected through a direct current to direct current integrated circuit, the direct current to direct current integrated circuit can be integrated by an on board charger circuit (OBC circuit for short) and a direct current conversion circuit (DC-DC converter DC-DC circuit for short), and the integrated circuit is respectively connected with the first conversion module, the high-voltage module and the low-voltage module.

In this embodiment, if energy is transmitted from the AC terminal of the AC power source to the capacitor C1 and is transmitted from the capacitor C1 to the capacitor C2 and/or the capacitor C3, respectively, the PFC module can be operated in the rectification mode; if the capacitor C1 transmits energy to the AC terminal of the AC power supply, it can be defined that the PFC module operates in an inverter mode; when the capacitor C1 transmits energy to the capacitor C2, the high-voltage module can be defined to work in a forward charging mode; when the capacitor C2 transmits energy in the direction of the capacitor C1, the high voltage module can be defined to operate in a reverse discharge mode; when the capacitor C1 transmits energy to the capacitor C3, the low voltage module can be defined to work in a forward power supply mode; when the capacitor C3 transmits energy in the direction of the capacitor C1, the low voltage module can be defined to operate in a reverse discharge mode; when the high-voltage module supplies power to the low-voltage module, namely when the capacitor C2 transmits the transmission capacity to the capacitor C3, the high-voltage module can be defined to work in a reverse discharge mode, and the low-voltage module can be defined to work in a forward power supply mode.

In an alternative embodiment, a non-isolated DC-DC regulated power supply, such as Buck, Boost, Buck-Boost, etc., may be connected in parallel between the capacitor C3 and the low-voltage battery. The voltage stabilization precision of the low-voltage battery end can be improved, and the input voltage received by the low-voltage battery is more stable.

Referring to fig. 3, which shows a schematic circuit structure diagram of one embodiment of the power transmission circuit of the present invention, in this embodiment, the first conversion module may include an AC power supply AC, a PFC module connected to the AC power supply AC, a filter capacitor C1 juxtaposed to the PFC module, and a first bridge switch circuit connected to the filter capacitor C1.

The PFC circuit can be a three-phase staggered circuit, so that an alternating current power supply AC can supply power to the high-voltage battery and the low-voltage battery respectively, and can also receive electric energy of the high-voltage battery or the low-voltage battery, or the alternating current power supply AC can supply power to the high-voltage battery and the voltage battery in a single-way mode.

In this embodiment, the PFC circuit may include two inductors and six MOS transistors, where the two inductors are respectively inductors L_PFC1Inductor L_PFC2Six MOS tubes are respectively Q_PFC1、Q_PFC2、Q_PFC3、Q_PFC4、Q_PFC5、Q_PFC6Two inductors L_PFC1Inductor L_PFC2Are respectively connected to a first end of an alternating current power supply AC so that L_PFC1And L_PFC2Parallel MOS transistor Q_PFC1Source terminal and Q_PFC4Is connected to the drain terminal of Q_PFC1And Q_PFC4In series, similarly, Q_PFC2Source terminal and Q_PFC5Is connected to the drain terminal of Q_PFC2And Q_PFC5In series, Q_PFC3Source terminal and Q_PFC6Is connected to the drain terminal of Q_PFC3And Q_PFC6Are connected in series. Inductor L_PFC1Is connected at a second terminal to Q_PFC1And Q_PFC4Connection terminal of, inductor L_PFC2Is connected at a second terminal to Q_PFC2And Q_PFC5A second end of the AC power supply is connected to Q_PFC3And Q_PFC6The connecting end of (1). MOS tube Q_PFC1、Q_PFC2And Q_PFC3The drain end of the MOS tube Q is respectively connected with the positive end of a filter capacitor C1 and the MOS tube Q_PFC4、Q_PFC5And Q_PFC6Respectively, connected to the terminals of the filter capacitor C1. The control module can be respectively connected with the MOS transistor Q_PFC1、Q_PFC2、Q_PFC3、Q_PFC4、Q_PFC5And a gate terminal of the QPFC6 is connected, and the conduction and the closing of the MOS tube can be controlled by controlling the gate terminal.

In this implementationIn example, Q_PFC3And Q_PFC6The diode can be used for replacement, so that the circuit cost can be reduced, and the volume of the integrated circuit can be reduced.

In this embodiment, the first bridge switch circuit may include 4 MOS transistors, an inductor L1, a capacitor C4, and a power coil. The 4 MOS transistors are Q1, Q2, Q3 and Q4 respectively, a source terminal of Q1 is connected with a drain terminal of Q3, Q1 is connected with Q3 in series, a source terminal of Q2 is connected with a drain terminal of Q4, Q2 is connected with Q4 in series, drain terminals of Q1 and Q2 are connected with an anode terminal of a filter capacitor C1 respectively, source terminals of Q3 and Q4 are connected with a cathode terminal of a filter capacitor C1 respectively, and Q1, Q2, Q3 and Q4 are connected into a bridge structure. The bridge structure circuit formed by the Q1, the Q2, the Q3 and the Q4 comprises two direct current ends and two alternating current ends which are respectively a first direct current end, a second direct current end, a first alternating current end and a second alternating current end. The first dc terminal may be connected to the inductor L1, the second dc terminal may be connected to the capacitor C4, the positive terminal of the first ac terminal filter capacitor C1, the second ac terminal may be connected to the negative terminal of the filter capacitor C1, or the negative terminal of the first ac terminal filter capacitor C1, and the second ac terminal may be connected to the positive terminal of the filter capacitor C1. Specifically, a first end of an inductor L1 is connected to a connection end of Q1 and Q3, a second end of an inductor L1 is connected to a first end of the power coil, a first end of a capacitor C4 is connected to a connection end of Q2 and Q4, a second end of a capacitor C4 is connected to a second end of the power coil, and the inductor L1 and the capacitor C4 are respectively connected to two ends of the power coil. In this embodiment, the high voltage module further includes a high voltage bridge switching circuit, which may be connected in parallel with the filter capacitor C2.

The high voltage bridge switching circuit includes: the high-voltage power supply comprises 4 MOS tubes, an inductor L2, a capacitor C5 and a high-voltage coil, wherein the 4 MOS tubes are Q5, Q6, Q7 and Q8 respectively, the source end of Q5 is connected with the drain end of Q7, the Q5 is connected with Q7 in series, the source end of Q6 is connected with the drain end of Q8, the Q6 is connected with the Q8 in series, the drain ends of Q5 and Q6 are connected with the positive electrode end of a filter capacitor C2 respectively, the source ends of Q7 and Q8 are connected with the negative electrode end of a filter capacitor C2 respectively, and Q5, Q6, Q7, Q8 and Q5 are connected into a bridge structure. The bridge structure circuit formed by the Q5, the Q6, the Q7 and the Q8 can comprise two direct current ends and two alternating current ends, namely a first direct current end, a second direct current end, a first alternating current end and a second alternating current end. The first dc terminal may be connected to the inductor L2, the second dc terminal may be connected to the capacitor C5, the first ac terminal may be connected to the positive terminal of the filter capacitor C2, the second ac terminal may be connected to the negative terminal of the filter capacitor C2, or the negative terminal of the filter capacitor C2 may be connected to the first ac terminal, and the second ac terminal may be connected to the positive terminal of the filter capacitor C2. Specifically, a first end of an inductor L2 is connected to a connection end of Q5 and Q7, a second end of an inductor L2 is connected to a first end of the high-voltage coil, a first end of a capacitor C5 is connected to a connection end of Q6 and Q8, a second end of a capacitor C5 is connected to a second end of the high-voltage coil, and the inductor L2 and the capacitor C5 are respectively connected to two ends of the high-voltage coil.

In the present embodiment, the low voltage module includes a low voltage battery, a BUCK-BOOST circuit connected in parallel with the low voltage battery, a filter capacitor C3 connected in parallel with the low voltage battery, and a low voltage bridge switch circuit connected in parallel with the filter capacitor C3.

The low-voltage bridge type switch circuit comprises two MOS (metal oxide semiconductor) tubes and a low-voltage coil, wherein the two MOS tubes are Q9 and Q10 respectively, the first end of the low-voltage coil is connected with the drain end of Q9, the second end of the low-voltage coil is connected with the source end of Q10, the source end of Q9 is connected with the drain end of Q10, the connecting end of Q9 and Q10 is connected with the positive end of a filter capacitor C3, and the negative end of the filter capacitor C3 is connected with the midpoint of the low-voltage coil.

In this embodiment, the two MOS transistors Q9 and Q10 can improve energy conversion efficiency, reduce the size of the integrated circuit, and facilitate the control of the MOS transistors by a technician to turn on or off.

Referring to fig. 4, a schematic circuit diagram of one embodiment of the power transmission circuit of the present invention is shown.

In an alternative embodiment, the low-voltage bridge switch circuit includes two unidirectional diodes D9 and D10, and a low-voltage coil, a first end of the low-voltage coil is connected to the positive terminal of D9, a second end of the low-voltage coil is connected to the positive terminal of D10, a negative terminal of D9 is connected to the positive terminal of the filter capacitor C3, a negative terminal of D10 is connected to the positive terminal of the filter capacitor C3, and a negative terminal of the filter capacitor C3 is connected to the midpoint of the low-voltage coil.

In the embodiment, the unidirectional diode is light and low in price, and the cost of the integrated circuit can be reduced.

In a specific implementation, the control module may control the MOS transistors Q1, Q2, Q3, and Q4 to operate in a full-bridge switching mode, control the MOS transistors Q5, Q6, Q7, and Q8 to operate in a full-bridge rectification topology switching mode, and control the MOS transistors Q9/D9 to Q10/D10 to operate in a center-tap rectification topology switching mode, so that the AC power source AC may respectively supply power to the high-voltage battery and the low-voltage battery.

Or when the MOS transistors Q1, Q2, Q3 and Q4 work in a full-bridge rectification topology switch mode, the MOS transistors Q5, Q6, Q7 and Q8 are controlled to work in the full-bridge topology switch mode, and the MOS transistors Q9/D9-Q10/D10 are controlled to work in a center-tap rectification topology switch mode, so that the high-voltage battery can respectively supply power to the low-voltage battery and the AC side of the AC power supply.

Or the MOS tubes Q1, Q2, Q3 and Q4 are controlled to be in an off mode, the MOS tubes Q9/D9-Q10/D10 are controlled to work in a center tap rectification topology switch mode, and the MOS tubes Q5, Q6, Q7 and Q8 are controlled to work in a half-bridge topology switch mode, so that the high-voltage battery can independently supply power to the low-voltage battery.

In this embodiment, four MOS transistors are adopted in the full-bridge switching circuit, and are connected into a diamond circuit, and are connected into a bridge structure, two diagonal points are ac input ends, and the other two diagonal points are dc output ends, so that unidirectional current guiding can be realized by using the current guiding function of the MOS transistors. In operation, when alternating current enters from the two alternating current input ends and passes through the bridge circuit, direct current can be output.

In specific operation, when the alternating current power supply AC is in a positive half cycle, the MOS transistors Q1 and Q4 are conducted, and Q2 and Q3 are closed, so that current flows into the L1 from the Q1, flows into the capacitor C4 through the coil, and then enters the alternating current power supply AC from the Q4 to form a loop; or Q1 and Q4 are closed, Q2 and Q3 are conducted, so that current flows into L1 from Q3, flows into a capacitor C4 through a coil, and then enters an alternating current power supply AC from Q2 to form a loop.

The full-bridge switching circuit can convert alternating current generated by the alternating current power supply AC into direct current to supply power to electric equipment and charge the storage battery, and can limit the current of the storage battery from reversely flowing back to the alternating current power supply AC to protect the alternating current power supply AC from being burnt out by reverse current. And the whole circuit has simple structure, low component cost and easy control, and can be convenient for technicians to operate.

In this embodiment, the full-bridge rectification topology switch circuit adopts four MOS transistors connected to form a diamond circuit, which are connected to form a bridge structure, two diagonal points are ac input ends, and the other two diagonal points are dc output ends.

In specific operation, MOS tubes Q5 and Q8 are switched on, Q6 and Q7 are switched off, so that the current of the high-voltage battery flows into L2 from Q5, flows into a capacitor C5 through a coil, and then enters the high-voltage battery from Q4 to form a loop; or Q5 and Q8 are closed, Q6 and Q7 are conducted, so that current flows into C5 from Q6, flows into L2 through the coil, and then enters the high-voltage battery from Q7 to form a loop.

The full-bridge rectification topology switch circuit can convert direct current of the high-voltage battery into alternating current, and the alternating current is used for reversely charging a low-voltage battery or an alternating current power supply AC. Or receive the direct current sent by the alternating current power supply AC to charge the high-voltage battery. The whole circuit structure of full-bridge rectification topology switch circuit is simple, the manufacturing cost is low, the filtering effect is good, the MOS tube bearing back pressure is small in the using process, and the service life of the product can be prolonged.

In this embodiment, the center-tapped rectifying topology switch circuit includes two MOS transistors and a low-voltage coil, a first end of the low-voltage coil is connected to a drain end of Q9, a second end of the low-voltage coil is connected to a source end of Q10, and a lead-out line is further connected to a negative end of a filter capacitor in the middle of the low-voltage coil.

The central tap rectification topology switch circuit can meet the requirements of various voltage inputs or outputs, the tap can slide, the voltage transmission transformation ratio can be adjusted, and the central tap is used as a middle position point, so that the number of rectifier tubes can be reduced, the number of original devices of the circuit is reduced, the circuit is simpler, and the cost of the whole circuit is reduced.

In this embodiment, the half-bridge rectification topology switch circuit may adopt two MOS transistors to operate simultaneously, and when receiving the ac power, may receive a positive half portion of a sine wave output by the ac power, and a negative half portion of the sine wave is suppressed, or alternatively outputs the dc power to form the ac power. In an alternative embodiment, the half-bridge topology switching mode may be: the Q5 and the Q7 are controlled to work in a switching mode of alternating conduction, the Q8 works in a constant conduction mode, and the Q6 is in a constant off mode. In the constant on mode of Q8 and the constant off mode of Q6, the alternating on of Q5 and Q7 is adjusted, the duty ratio of power transmission can be adjusted, and the voltage can be adjusted according to the actual transmission requirement.

Specifically, when the half-bridge topology switching mode is adopted, Q6 is in a constant turn-off mode, Q6 does not work and generates no working loss, Q8 is in a very constant turn-on mode, Q8 only has a conduction loss, Q5 and Q7 are alternately used, when Q5 is used, Q7 is closed, Q7 also generates no working loss, and similarly, when Q5 is closed, Q5 also generates no loss, and Q7 is switched on and uses only a conduction loss. In whole working process, only two MOS pipes produce the conduction loss, and two other MOS pipes do not produce working loss to can effectively reduce the working loss of each part, increase the life of product, promote circuit's practicality, through using in turn between control Q5, the Q7 moreover, output duty cycle that can control current can realize voltage regulation.

In another alternative embodiment, the half-bridge topology switch mode may also be: the Q6 and the Q8 are controlled to work in a switching mode of alternating conduction, the Q7 works in a constant conduction mode, and the Q5 works in a constant turn-off mode.

Similarly, when the half-bridge topology switch mode is adopted, Q5 is in a constant turn-off mode, Q5 does not work, no working loss is generated, Q7 is in a very constant turn-on mode, Q7 only has a conduction loss, Q6 and Q8 are alternately used, when Q6 is used, Q8 is closed, Q8 does not generate a working loss, when Q6 is closed, Q6 also has no loss, Q8 is used in a conduction mode, the working loss of each component can be effectively reduced, the service life of a product is prolonged, and therefore the practicability of the circuit is improved.

In a specific implementation, the first bridge switch circuit, the high-voltage bridge switch circuit and the low-voltage bridge switch circuit are coupled with each other through coils, the alternating current part and the direct current part of the circuits can be coupled by increasing the voltage between the circuits, and the effect of energy transmission can be achieved by configuring proper impedance at two ends.

In this embodiment, when the high-voltage battery provides the power supply mode of the energy to the low-voltage battery, the Q5 to Q8 are controlled to operate in the half-bridge topology switching state, so that the number of elements in the switching state and the switching loss can be reduced, the power transmission efficiency is improved, and the power supply efficiency for supplying power to the low-voltage battery in the light load state is also improved.

Referring to fig. 5, a schematic circuit diagram of one embodiment of the power transmission circuit of the present invention is shown.

In another alternative embodiment, the PFC circuit may include four bridge unidirectional diodes, two parallel inductors, and two parallel MOS transistors, where the four bridge unidirectional diodes are D respectively_RECT1、D_RECT2、D_RECT3And D_RECT4Two parallel unidirectional diodes are respectively D_PFC1And D_PFC2Two parallel inductors are respectively L_PFC1And L_PFC2Two parallel MOS tubes are respectively Q_PFC1And Q_PFC2. Wherein D_RECT1Positive terminal of (1) and (D)_RECT3Is connected to the negative terminal of D_RECT2Positive terminal of (1) and (D)_RECT4Is connected to the negative terminal of D_RECT1Negative terminal of (1) and (D)_RECT2Is connected to the negative terminal of D_RECT3Positive terminal of (1) and (D)_RECT4Is connected with the positive terminal. First terminal of AC power supply and D_RECT1And D_RECT3Is connected with the second end of the AC power supply AC and D_RECT2And D_RECT4Are connected. D_RECT1And D_RECT2Respectively connected with the inductor L_PFC1And L_PFC2Is connected to a first end of, L_PFC1Second terminal and D_PFC1Positive terminal connection, L_PFC2Second terminal and D_PFC2Positive terminal connection, D_PFC1Negative terminal and D_PFC2The negative terminal is connected with the positive terminal of the filter capacitor C1. MOS tube Q_PFC1Drain terminal and L_PFC1And D_PFC1Is connected with the connection end of the MOS tube Q_PFC2Drain terminal and L_PFC2And D_PFC2Is connected with the connection end of the MOS tube Q_PFC1And MOS transistor Q_PFC2Is connected to the negative terminal of the filter capacitor C1. Unidirectional diode D_RECT3And D_RECT4May be connected to the negative terminal of the filter capacitor C1.

In this embodiment, D_PFC1And D_PFC2A metal oxide semiconductor field effect transistor (MOSFET, abbreviated as MOS transistor) may be used instead, so as to improve the power conversion efficiency.

Referring to fig. 6, a schematic circuit diagram of a power transmission circuit according to an embodiment of the present invention is shown.

In an alternative embodiment, the power module and the high-voltage module have the same structure as the above-mentioned embodiment, and can achieve the same technical effect, and for avoiding repetition, it is not described herein again, but refer to the above-mentioned embodiment, where the low-voltage bridge switching circuit includes two unidirectional diodes and a low-voltage coil, the two unidirectional diodes are D9 and D10, respectively, a first end of the low-voltage coil is connected to the positive terminal of D9, a second end of the low-voltage coil is connected to the positive terminal of D10, a negative end of D9 is connected to the positive terminal of the filter capacitor C3, a negative end of D10 is connected to the positive terminal of the filter capacitor C3, and a negative end of the filter capacitor C3 is connected to the midpoint of the low-voltage coil.

In a specific implementation, the control module may be respectively connected to the gate terminals of the MOS transistors, and the MOS transistors may be controlled to be turned on and off by controlling the gate terminals, so that the MOS transistors may achieve the purpose of switching.

In this embodiment, the PFC circuit may employ a bidirectional conversion topology circuit that may perform both an AC-DC rectification function and a DC-AC inversion function. The high voltage bridge switching circuit may employ a bidirectional conversion topology that can operate in both a forward charging mode and a reverse discharging mode. The high-voltage bridge type switching circuit can adopt a bridgeless PFC circuit architecture, has the function of charging the high-voltage battery and the low-voltage battery by the AC power supply AC, and also has the function of providing AC energy to the AC side of the AC power supply board by the high-voltage battery/the low-voltage battery, thereby realizing the function of bidirectional charging and discharging.

In the present invention, the MOS transistors (MOSFETs) in the circuit diagrams of all embodiments may also be replaced by electronic devices with similar functions, such as IGBTs or bipolar transistors, and the inductors L1 and L2 and the capacitors C4 and C5 in the circuit diagrams of all embodiments may use discrete devices, or may be integrated with the transformer Tx1 by an integration technique.

The utility model provides a power transmission circuit, this circuit can be integrated with the degree of depth of on-vehicle OBC power module and DC power module, reduce integrated circuit's components and parts quantity, thereby make integrated circuit smaller and more exquisite light, can increase vehicle mounted power's reliability, also can reduce vehicle mounted power's cost, this integrated circuit has used the resonance soft switch circuit topology of symmetry moreover, vehicle mounted power's transmission power can be promoted, be favorable to electric automobile to increase continuation of the journey mileage, and reduce energy storage unit's cost.

The embodiments in the present specification are described in a progressive manner, each embodiment focuses on differences from other embodiments, and the same and similar parts among the embodiments are referred to each other.

As will be appreciated by one skilled in the art, embodiments of the present invention may be provided as a method, apparatus, or computer program product. Accordingly, embodiments of the present invention may take the form of an entirely hardware embodiment, an entirely software embodiment or an embodiment combining software and hardware aspects. Furthermore, embodiments of the present invention may take the form of a computer program product embodied on one or more computer-usable storage media (including, but not limited to, disk storage, CD-ROM, optical storage, and the like) having computer-usable program code embodied therein.

Embodiments of the present invention are described with reference to flowchart illustrations and/or block diagrams of circuits, terminal devices (systems), and computer program products according to embodiments of the invention. It will be understood that each flow and/or block of the flow diagrams and/or block diagrams, and combinations of flows and/or blocks in the flow diagrams and/or block diagrams, can be implemented by computer program instructions. These computer program instructions may be provided to a processor of a general purpose computer, special purpose computer, embedded processor, or other programmable data processing terminal to produce a machine, such that the instructions, which execute via the processor of the computer or other programmable data processing terminal, create means for implementing the functions specified in the flowchart flow or flows and/or block diagram block or blocks.

These computer program instructions may also be stored in a computer-readable memory that can direct a computer or other programmable data processing terminal to function in a particular manner, such that the instructions stored in the computer-readable memory produce an article of manufacture including instruction means which implement the function specified in the flowchart flow or flows and/or block diagram block or blocks.

These computer program instructions may also be loaded onto a computer or other programmable data processing terminal to cause a series of operational steps to be performed on the computer or other programmable terminal to produce a computer implemented process such that the instructions which execute on the computer or other programmable terminal provide steps for implementing the functions specified in the flowchart flow or flows and/or block diagram block or blocks.

While preferred embodiments of the present invention have been described, additional variations and modifications of these embodiments may occur to those skilled in the art once they learn of the basic inventive concepts. It is therefore intended that the following claims be interpreted as including the preferred embodiments and all changes and modifications that fall within the scope of the embodiments of the invention.

Finally, it should also be noted that, herein, relational terms such as first and second, and the like may be used solely to distinguish one entity or action from another entity or action without necessarily requiring or implying any actual such relationship or order between such entities or actions. Also, the terms "comprises," "comprising," or any other variation thereof, are intended to cover a non-exclusive inclusion, such that a process, method, article, or terminal that comprises a list of elements does not include only those elements but may include other elements not expressly listed or inherent to such process, method, article, or terminal. Without further limitation, an element defined by the phrase "comprising an … …" does not exclude the presence of other like elements in a process, method, article, or terminal that comprises the element.

The above detailed description is made on the power transmission circuit provided by the present invention, and the principle and the implementation of the present invention are explained by applying a specific example, and the description of the above embodiment is only used to help understanding the method and the core idea of the present invention; meanwhile, for the general technical personnel in the field, according to the idea of the present invention, there are changes in the specific implementation and application scope, to sum up, the content of the present specification should not be understood as the limitation of the present invention.

Claims

1. A power transmission circuit is characterized by comprising a first conversion module, a high-voltage module, a low-voltage module and a control module, wherein the high-voltage module and the low-voltage module are respectively connected with the first conversion module;

the control module is used for controlling the high-voltage bridge type switching circuit to be in a full-bridge rectification topology switching mode and controlling the low-voltage bridge type switching circuit to be in a center-tap rectification topology switching mode when the first bridge type switching circuit is in the full-bridge switching module, so that the first switching module respectively charges the high-voltage module and the low-voltage module;

2. The circuit of claim 1, wherein the control module further comprises:

3. The circuit of claim 1, wherein the first conversion module further comprises an ac power source, a PFC circuit coupled to the ac current, an inductor L1 and a capacitor C4 coupled to the first dc terminal and the second dc terminal of the power bridge circuit, respectively, and a power coil coupled in series with the first terminal of the inductor L1 and the first terminal of the capacitor C4, respectively, the PFC circuit coupled to the first ac terminal and the second ac terminal of the power bridge circuit.

4. The circuit of claim 3, wherein the first bridge switching circuit comprises: the MOS transistors comprise 4 MOS transistors which are respectively Q1, Q2, Q3 and Q4, wherein the Q1 is connected with the Q3 in series, the Q2 is connected with the Q4 in series, the Q1 is connected with the Q3, the Q2 is connected with the Q4 in parallel, the Q1, the Q2, the Q3 and the Q4 are connected into a bridge structure, the Q1 is connected with the connection end of the Q3 and the second end of an inductor L1, and the Q2 is connected with the connection end of the Q4 and the second end of a capacitor C4.

5. The circuit of claim 1, wherein the high voltage module further comprises a high voltage battery, a filter capacitor C2 connected in parallel with the high voltage battery, an inductor L2 and a capacitor C5 connected across the high voltage bridge switch circuit, respectively, and a high voltage coil connected in series with a first terminal of the inductor L2 and a first terminal of the capacitor C5, respectively, the high voltage bridge switch circuit being connected across the filter capacitor C2, respectively.

6. The circuit of claim 5, wherein the high voltage bridge switching circuit comprises: 4 MOS tubes, Q5, Q6, Q7 and Q8 respectively, wherein the Q5 is connected with the Q7 in series, the Q6 is connected with the Q8 in series, the Q5 is connected with the Q7 and the Q6 is connected with the Q8 in parallel, so that the Q5, the Q6, the Q7 and the Q8 are connected into a bridge structure, the Q5 is connected with the connection end of the Q7 and the second end of an inductor L2, and the Q6 is connected with the connection end of the Q8 and the second end of a capacitor C5.

7. The circuit of claim 6, wherein the controlling the high voltage bridge switching circuit in a half bridge rectifier topology switching mode comprises:

controlling the Q5 and the Q7 to be in an alternately conducting switching mode, controlling the Q8 to be in a constantly conducting switching mode, and controlling the Q6 to be in a constantly off switching mode;

or, the Q6 and the Q8 are controlled to be in a switching mode of alternating conduction, the Q7 is controlled to be in a switching mode of constant conduction, and the Q5 is controlled to be in a switching mode of constant disconnection.

8. The circuit of claim 1, wherein the low voltage module further comprises a low voltage battery, a filter capacitor C3 connected in parallel with the low voltage battery, and low voltage coils connected across the low voltage bridge switching circuit, respectively, the low voltage bridge switching circuit being connected to the filter capacitor C3.

9. The circuit of claim 8, wherein the low voltage bridge switch circuit comprises two MOS transistors, Q9 and Q10, the two ends of the low voltage coil are respectively connected to the first end of Q9 and the first end of Q10, the second end of Q9 is connected to the positive terminal of the filter capacitor C3, the second end of Q10 is connected to the positive terminal of the filter capacitor C3, and the negative terminal of the filter capacitor C3 is connected to the midpoint of the low voltage coil.

10. The circuit of claim 9, wherein the low voltage bridge switch circuit comprises two unidirectional diodes, D9 and D10, the two ends of the low voltage coil are respectively connected to the positive terminals of D9 and D10, the negative terminal of D9 is connected to the positive terminal of the filter capacitor C3, the negative terminal of D10 is connected to the positive terminal of the filter capacitor C3, and the negative terminal of the filter capacitor C3 is connected to the midpoint of the low voltage coil.