Charging control circuit and vehicle-mounted charger

Abstract

The invention provides a charging control circuit and a vehicle-mounted charger, the charging control circuit comprises a first primary side conversion circuit and a first secondary side conversion circuit which are connected with a first transformer, the first primary side conversion circuit comprises a matrix type rectifier bridge and a resonance network, a first AC side of the matrix type rectifier bridge is a first port, and a second AC side of the matrix type rectifier bridge is a second port; a second alternating current side of the matrix rectifier bridge is connected with the first transformer through the resonance network; the second primary side conversion circuit and the second secondary side conversion circuit are connected with the second transformer; wherein the first transformer and the second transformer are mutually independent, the direct current side of the first secondary side conversion circuit is a high-voltage second port, and the direct current side of the second secondary side conversion circuit is a low-voltage third port. The power factor can be effectively improved through the matrix type rectifier bridge, harmonic pollution to a power grid is reduced, meanwhile, the circuit works at a specific frequency through the resonance network, the switching loss is reduced, the efficiency is improved, and the size and the weight of the circuit are also reduced.

Description

Technical Field

[0001] The present application relates to the field of charging technology, and in particular to a charging control circuit and an on-board charger. Background Art

[0002] With the rapid development of new energy technologies, electric vehicles are becoming increasingly popular due to their energy-saving and environmentally friendly advantages. The on-board charger (OBC) and on-board DC-DC (Direct Current Control) are important components of electric vehicles, charging the high-voltage battery and low-voltage battery, respectively.

[0003] However, in related technologies, the on-board charger and on-board DCDC are two independent components. Even if the two are integrated into one, the number of switching devices and passive devices in the on-board charger is not fundamentally optimized, resulting in defects such as large size and high cost. At the same time, since the number of OBC power conversion stages is not reduced and the inverter function is not supported, it not only affects the conversion efficiency of on-board charging, but also cannot meet various charging scenarios. Summary of the Invention

[0004] In view of the above shortcomings of the prior art, the purpose of this application is to provide a charging control circuit and an on-board charger to solve the problems of large size and high cost of existing integrated charging circuits.

[0005] To achieve the above-mentioned objectives and other related objectives, the first aspect of the present application provides a charging control circuit, comprising: a first primary-side conversion circuit and a first secondary-side conversion circuit connected to a first transformer, the first primary-side conversion circuit comprising a matrix rectifier bridge and a resonant network, the first AC side of the matrix rectifier bridge being a first port, and the second AC side of the matrix rectifier bridge being connected to the first transformer through the resonant network; a second primary-side conversion circuit and a second secondary-side conversion circuit connected to the second transformer; wherein the first transformer and the second transformer are independent of each other, the DC side of the first secondary-side conversion circuit being a high-voltage second port, and the DC side of the second secondary-side conversion circuit being a low-voltage third port.

[0006] In one embodiment of the present application, the matrix rectifier bridge includes a first bridge arm and a second bridge arm, the first bridge arm and the second bridge arm constitute a full bridge structure, and the upper bridge arm and the lower bridge arm of each bridge arm are composed of at least one group of switches with opposite polarity.

[0007] In one embodiment of the present application, the upper arm of the first bridge arm is composed of a first switching tube and a second switching tube with opposite polarities, and the lower arm of the first bridge arm is composed of a third switching tube and a fourth switching tube with opposite polarities; the upper arm of the second bridge arm is composed of a fifth switching tube and a sixth switching tube with opposite polarities, and the lower arm of the second bridge arm is composed of a seventh switching tube and an eighth switching tube with opposite polarities.

[0008] In one embodiment of the present application, the matrix rectifier bridge includes a first bridge arm and a second bridge arm, the first bridge arm and the second bridge arm constitute a full-bridge structure, the upper bridge arm of the first bridge arm is a first bidirectional GaN device, and the lower bridge arm of the first bridge arm is a second bidirectional GaN device; the upper bridge arm of the second bridge arm is a third bidirectional GaN device, and the lower bridge arm of the second bridge arm is a fourth bidirectional GaN device.

[0009] In one embodiment of the present application, the matrix rectifier bridge includes a first bridge arm and a second bridge arm, the first bridge arm and the second bridge arm constitute a full-bridge structure, the upper bridge arm of the first bridge arm is a first bidirectional GaN device, and the lower bridge arm of the first bridge arm is a second bidirectional GaN device; the upper bridge arm of the second bridge arm is composed of a fifth switch tube and a sixth switch tube with opposite polarities, and the lower bridge arm of the second bridge arm is composed of a seventh switch tube and an eighth switch tube with opposite polarities.

[0010] In one embodiment of the present application, the matrix rectifier bridge includes a first bridge arm and a second bridge arm, the first bridge arm and the second bridge arm constitute a full-bridge structure, the upper and lower bridge arms in the first bridge arm and the second bridge arm are composed of bidirectional GaN devices and back-to-back switches, and the back-to-back switches are composed of two switches with opposite polarities.

[0011] In one embodiment of the present application, a back-to-back common drain structure is formed between the two switches with opposite polarities.

[0012] In one embodiment of the present application, the drive signal of the first switching tube and the upper drive signal of the first bidirectional GaN device are the 1a drive signal, and the drive signal of the second switching tube and the lower drive signal of the first bidirectional GaN device are the 1b drive signal; the drive signal of the third switching tube and the upper drive signal of the second bidirectional GaN device are the 2a drive signal, and the drive signal of the fourth switching tube and the lower drive signal of the second bidirectional GaN device are the 2b drive signal; the drive signal of the fifth switching tube and the upper drive signal of the third bidirectional GaN device are the 3a drive signal, and the drive signal of the sixth switching tube and the lower drive signal of the third bidirectional GaN device are the 3b drive signal; the drive signal of the seventh switching tube and the upper drive signal of the fourth bidirectional GaN device are the 4a drive signal, and the drive signal of the eighth switching tube and the lower drive signal of the fourth bidirectional GaN device are the 4b drive signal.

[0013] In one embodiment of the present application, it also includes: when power is transmitted from the first port to the second port, or power is transmitted from the second port to the first port, the second transformer is short-circuited by controlling the conduction state in the second secondary conversion circuit to prevent energy from being transmitted to the third port through the second transformer; or, when power is transmitted from the second port to the third port, or power is transmitted from the third port to the second port, the first transformer is short-circuited by controlling the conduction state in the first secondary conversion circuit to prevent energy from being transmitted to the first port through the first transformer.

[0014] In one embodiment of the present application, the resonant network includes a first resonant inductor, a first resonant capacitor and an excitation inductor. The midpoint of the first bridge arm is connected to the same-name end of the first winding in the first transformer through the first resonant inductor, the midpoint of the second bridge arm is connected to the opposite-name end of the first winding through the first resonant capacitor, and the excitation inductor is connected in parallel at both ends of the first winding.

[0015] In one embodiment of the present application, the first secondary side conversion circuit includes a third bridge arm and a fourth bridge arm, the first transformer includes a second winding as a secondary coil, wherein the second winding is connected between the midpoint of the third bridge arm and the midpoint of the fourth bridge arm; the second primary side conversion circuit includes a fifth bridge arm and a shared fourth bridge arm, the second transformer includes a third winding as a main coil, wherein the third winding is connected between the midpoint of the fourth bridge arm and the midpoint of the fifth bridge arm, and the two ends of the third bridge arm, the fourth bridge arm and the fifth bridge arm serve as a second port for connecting high voltage direct current.

[0016] In one embodiment of the present application, the upper and lower bridge arms of the third bridge arm are respectively the ninth switch tube and the tenth switch tube, the upper and lower bridge arms of the fourth bridge arm are respectively the eleventh switch tube and the twelfth switch tube; the upper and lower bridge arms of the fifth bridge arm are respectively the thirteenth switch tube and the fourteenth switch tube, wherein the drive signals corresponding to the ninth switch tube, the tenth switch tube, the eleventh switch tube, the twelfth switch tube, the thirteenth switch tube and the fourteenth switch tube are respectively the fifth drive signal, the sixth drive signal, the seventh drive signal, the eighth drive signal, the ninth drive signal and the tenth drive signal.

[0017] In one embodiment of the present application, the control method of the charging control circuit includes: when the three ports are operating in the forward direction, if the voltage of the first port is greater than zero, the 1a drive signal, the 2a drive signal, the 3a drive signal, and the 4a drive signal are continuously on signals, and the 1b drive signal and the 4b drive signal control the corresponding switch tubes to turn on and off at a preset duty cycle and a preset frequency, wherein the 4b drive signal lags behind the 1b drive signal by a first preset time, the 1b drive signal and the 2b drive signal are complementary, and the 3b drive signal and the 4b drive signal are complementary;

[0018] At the second port, based on the phase-shift control strategy, the fifth drive signal and the eighth drive signal control the corresponding switch tube to be turned on and off with a preset duty cycle and a preset frequency, and the fifth drive signal lags behind the 1b drive signal by a second preset time, and the eighth drive signal lags behind the fifth drive signal by a third preset time. By controlling the first secondary-side conversion circuit, the AC voltage is rectified into a DC voltage, and power is transmitted to the second port; wherein, the fifth drive signal and the sixth drive signal, as well as the seventh drive signal and the eighth drive signal, are complementary; at the same time, based on the phase-shift control strategy, the ninth drive signal controls the corresponding switch tube to be turned on and off with a preset duty cycle and a preset frequency, and the ninth drive signal leads or lags behind the eighth drive signal by a fourth preset time, wherein the ninth drive signal and the tenth drive signal are complementary.

[0019] In one embodiment of the present application, the control method of the charging control circuit further includes: when the three ports are operating in the forward direction, if the voltage of the first port is less than zero, the 1b drive signal, the 2b drive signal, the 3b drive signal, and the 4b drive signal are continuously on signals, and the 2a drive signal and the 3a drive signal control the corresponding switch tubes to turn on and off at a preset duty cycle and a preset frequency, wherein the 3a drive signal lags behind the 2a drive signal by a fifth preset time, the 1a drive signal and the 2a drive signal are complementary, and the 3a drive signal and the 4a drive signal are complementary;

[0020] At the second port, based on the phase-shift control strategy, the fifth drive signal and the eighth drive signal control the corresponding switch tube to be turned on and off with a preset duty cycle and a preset frequency, and the fifth drive signal lags behind the 2a drive signal by a sixth preset time, and the eighth drive signal lags behind the fifth drive signal by a seventh preset time. By controlling the first secondary-side conversion circuit, the AC voltage is rectified into a DC voltage, and power is transmitted to the second port; wherein, the fifth drive signal and the sixth drive signal, as well as the seventh drive signal and the eighth drive signal, are complementary; at the same time, based on the phase-shift control strategy, the ninth drive signal controls the corresponding switch tube to be turned on and off with a preset duty cycle and a preset frequency, and the ninth drive signal leads or lags behind the eighth drive signal by an eighth preset time, wherein the ninth drive signal and the tenth drive signal are complementary.

[0021] In one embodiment of the present application, the control method of the charging control circuit further includes: when the three ports are operating in the forward direction, if the voltage of the first port is less than zero, the 1b drive signal, the 2b drive signal, the 3b drive signal, and the 4b drive signal are continuously on signals, and the 2a drive signal and the 3a drive signal control the corresponding switch tubes to turn on and off at a preset duty cycle and a preset frequency, wherein the 2a drive signal lags behind the 3a drive signal by a fifth preset time, the 1a drive signal and the 2a drive signal are complementary, and the 3a drive signal and the 4a drive signal are complementary;

[0022] At the second port, based on the phase-shift control strategy, the fifth drive signal and the eighth drive signal control the corresponding switch tube to be turned on and off with a preset duty cycle and a preset frequency, and the fifth drive signal lags behind the 3a drive signal by a sixth preset time, and the eighth drive signal lags behind the fifth drive signal by a seventh preset time. By controlling the first secondary-side conversion circuit, the AC voltage is rectified into a DC voltage, and power is transmitted to the second port; wherein, the fifth drive signal and the sixth drive signal, as well as the seventh drive signal and the eighth drive signal, are complementary; at the same time, based on the phase-shift control strategy, the ninth drive signal controls the corresponding switch tube to be turned on and off with a preset duty cycle and a preset frequency, and the ninth drive signal leads or lags behind the eighth drive signal by an eighth preset time, wherein the ninth drive signal and the tenth drive signal are complementary.

[0023] In one embodiment of the present application, the control method of the charging control circuit further includes: when operating in reverse three-port mode, if the voltage of the first port is greater than zero, the first, second, third, and fourth drive signals are continuously on signals; based on a phase-shift control strategy, the fifth and eighth drive signals control the corresponding switching transistors to turn on and off at a preset duty cycle and a preset frequency, and the eighth drive signal lags behind the fifth drive signal by a first preset time, thereby inverting a DC voltage into an AC voltage; wherein the fifth and sixth drive signals, as well as the seventh and eighth drive signals, are complementary;

[0024] The 1b drive signal and the 4b drive signal control the corresponding switch tubes to turn on and off at a preset duty cycle and a preset frequency, and the 1b drive signal lags behind the 5th drive signal by a second preset time, and the 4b drive signal lags behind the 1b drive signal by a third preset time, so that the AC voltage transmits power to the first port, wherein the 1b drive signal and the 2b drive signal are complementary, and the 3b drive signal and the 4b drive signal are complementary.

[0025] In one embodiment of the present application, the control method of the charging control circuit further includes:

[0026] During reverse three-port operation, if the voltage of the first port is less than zero, the 1b drive signal, the 2b drive signal, the 3b drive signal, and the 4b drive signal are continuously on signals, and based on the phase-shift control strategy, the 5th drive signal and the 8th drive signal control the corresponding switch tubes to turn on and off at a preset duty cycle and a preset frequency, and the 8th drive signal lags behind the 5th drive signal by a fifth preset time; the DC voltage is inverted into an AC voltage, wherein the 5th drive signal and the 6th drive signal, as well as the 7th drive signal and the 8th drive signal, are complementary;

[0027] The 2a drive signal and the 3a drive signal control the corresponding switch tube to be turned on and off at a preset duty cycle and a preset frequency, and the 2a drive signal lags behind the 5th drive signal by a sixth preset time, and the 3a drive signal lags behind the 2a drive signal by a seventh preset time, so that the AC voltage transmits power to the first port, wherein the 1a drive signal and the 2a drive signal are complementary to each other, and the 3a drive signal and the 4a drive signal are complementary to each other.

[0028] In one embodiment of the present application, the control method of the charging control circuit includes: The control method of the charging control circuit also includes:

[0029] During reverse three-port operation, if the voltage of the first port is less than zero, the 1b drive signal, the 2b drive signal, the 3b drive signal, and the 4b drive signal are continuously on signals, and based on the phase-shift control strategy, the 5th drive signal and the 8th drive signal control the corresponding switch tubes to turn on and off at a preset duty cycle and a preset frequency, and the 8th drive signal lags behind the 5th drive signal by a fifth preset time; the DC voltage is inverted into an AC voltage, wherein the 5th drive signal and the 6th drive signal, as well as the 7th drive signal and the 8th drive signal, are complementary;

[0030] The 2a drive signal and the 3a drive signal control the corresponding switch tube to turn on and off at a preset duty cycle and a preset frequency, and the 3a drive signal lags behind the 5th drive signal by a sixth preset time, and the 2a drive signal lags behind the 3a drive signal by a seventh preset time, so that the AC voltage transmits power to the first port, wherein the 1a drive signal and the 2a drive signal are complementary to each other, and the 3a drive signal and the 4a drive signal are complementary to each other.

[0031] In one embodiment of the present application, the control method of the charging control circuit further includes: when a single low-voltage DC-DC circuit is operating, the 1a, 1b, 2a, 2b, 3a, 3b, 4a, and 4b drive signals are shutdown signals, and phase-shifted full-bridge control or variable duty cycle control is performed on the three bridge arms and the fourth bridge arm; the fifth drive signal and the seventh drive signal control the corresponding switching tubes to be synchronously turned on and off, and the sixth drive signal and the eighth drive signal control the corresponding switching tubes to be synchronously turned on and off, so that the voltage between the third bridge arm and the fourth bridge arm approaches zero;

[0032] In which, when the low-voltage DCDC is working alone in step-down mode, the voltage duty cycle of the midpoint of the fourth bridge arm and the fifth bridge arm or the operating duty cycle of the switch tube in the fourth bridge arm and the fifth bridge arm is adjusted, and the high-voltage DC voltage is converted into a low-voltage DC voltage through synchronous rectification, and power is transmitted to the third port; or, when the low-voltage DCDC is working alone in step-up mode, whether the second primary side conversion circuit performs synchronous rectification is controlled to convert the low-voltage DC voltage into a high-voltage DC voltage, and power is transmitted to the second port.

[0033] A second aspect of the present application provides a vehicle-mounted charger, comprising the above-mentioned charging control circuit.

[0034] As described above, the technical solution of a charging control circuit and an on-board charger provided by this application has the following beneficial effects:

[0035] By introducing a matrix rectifier bridge into the charging control circuit, different switch conduction combinations are used in the positive and negative half-cycles of the AC input to achieve bidirectional conversion from AC to DC. This can effectively improve the power factor and reduce harmonic pollution to the power grid. By using a resonant network to operate at a specific frequency, switching losses are reduced, efficiency is improved, and the size and weight of the circuit are reduced. At the same time, by using two independent transformers and corresponding conversion circuits, high-voltage DC and low-voltage DC can be output simultaneously to meet the needs of various loads, thereby improving the flexibility of the charging control solution and the practicality of various usage scenarios. BRIEF DESCRIPTION OF THE DRAWINGS

[0036] Figure 1 Shown is a circuit diagram of a charging control circuit provided by the present application;

[0037] Figure 2 Another circuit diagram showing a charging control circuit provided by the present application;

[0038] Figure 3 Shown is a first timing control diagram corresponding to the switches of a charging control circuit provided by the present application when the three forward ports work simultaneously;

[0039] Figure 4 Shown is a second timing control diagram corresponding to the switches of a charging control circuit provided by the present application when the three forward ports work simultaneously;

[0040] Figure 5 Shown is a first timing control diagram corresponding to the switches of a charging control circuit provided by the present application when three ports in reverse direction work simultaneously;

[0041] Figure 6 The figure shows a second timing control diagram corresponding to the switches of a charging control circuit provided by the present application when the three ports in reverse direction work simultaneously. DETAILED DESCRIPTION

[0042] The following describes the embodiments of the present application through specific examples. Those skilled in the art can easily understand the other advantages and effects of the present application from the content disclosed in this specification. The present application can also be implemented or applied through other different specific embodiments. The details in this specification can also be modified or changed based on different viewpoints and applications without departing from the spirit of the present application. It should be noted that the following embodiments and features in the embodiments can be combined with each other unless they conflict.

[0043] It should be noted that the illustrations provided in the following embodiments are only schematic illustrations of the basic concept of the present application. Therefore, the illustrations only show components related to the present application and are not drawn according to the number, shape and size of components in actual implementation. In actual implementation, the type, quantity and proportion of each component can be changed at will, and the component layout type may also be more complicated.

[0044] The present invention is described in detail below through specific examples. Figure 1 As shown, Figure 1 A circuit diagram of a charging control circuit provided in this application includes the following steps:

[0045] A first primary conversion circuit and a first secondary conversion circuit are connected to the first transformer T1, the first primary conversion circuit includes a matrix rectifier bridge and a resonant network, the first AC side of the matrix rectifier bridge is a first port (i.e., AC end), and the second AC side of the matrix rectifier bridge is connected to the first transformer T1 through the resonant network; a second primary conversion circuit and a second secondary conversion circuit are connected to the second transformer T2; wherein the first transformer T1 and the second transformer T2 are independent of each other, the DC side of the first secondary conversion circuit is a high-voltage second port (i.e., HVDC port), and the DC side of the second secondary conversion circuit is a low-voltage third port (i.e., LVDC port).

[0046] When power is transmitted from the first port to the second port, or when power is transmitted from the second port to the first port, the second transformer is short-circuited by controlling the conduction state in the second secondary conversion circuit to prevent energy from being transmitted to the third port through the second transformer; or, when power is transmitted from the second port to the third port, or when power is transmitted from the third port to the second port, the first transformer is short-circuited by controlling the conduction state in the first secondary conversion circuit to prevent energy from being transmitted to the first port through the first transformer.

[0047] It should be noted that the charging control circuit of the present application can be widely used in vehicle-mounted chargers, integrating an independent vehicle-mounted charger and a DCDC module. The first port can be connected to the mains, the load of the second port can be a battery or a power battery, and the third port can be connected to various external loads in the vehicle.

[0048] It should be understood that by controlling the on and off of the switching tubes in the first primary-side conversion circuit, the first secondary-side conversion circuit, the second primary-side conversion circuit and the second secondary-side conversion circuit, it can be understood as a dedicated chip (logic gate circuit), microprocessor, digital signal processor or processor that generates timing control logic, and they will not be described one by one here.

[0049] The number of primary and secondary windings, as well as the turns ratio, of the first transformer T1 and the second transformer T2 can be modified based on user needs to accommodate different voltage conversion requirements and are not limited here. For example, the first primary-side conversion circuit can employ a full-bridge rectifier topology, while the second secondary-side conversion circuit can employ different topologies, such as a buck circuit or a boost circuit, to achieve different voltage regulation functions.

[0050] For example, AC power is connected to the first AC side of a matrix rectifier bridge through the first port. The matrix rectifier bridge can achieve bidirectional energy transmission through the bidirectional conduction characteristics of fully controlled devices. The AC power then enters the resonant network, generating a resonant current, which is then transmitted to the primary coil (winding) of the first transformer. The secondary coil (winding) of the first transformer outputs AC power, which is then processed by the rectification and filtering circuits and outputs high-voltage DC power at the second port. The second primary conversion circuit converts the DC power and outputs AC power, which is transmitted to the primary coil of the second transformer. The secondary coil of the second transformer outputs AC power, which is converted and outputs low-voltage DC power at the third port to power various loads in the vehicle.

[0051] Specifically, if Figure 1 As shown, the first winding n1 is connected to the AC port through the first primary conversion circuit, the second winding n2 is connected to the HVDC port through the first secondary conversion circuit, the third winding n3 is connected to the LVDC port through the second primary conversion circuit, and the fourth windings n4 (i.e., the positive winding segment) and n5 (i.e., the negative winding segment) are connected to the LVDC port through the second secondary conversion circuit. By controlling the on and off of the switches in the first primary conversion circuit, the first secondary conversion circuit, the second primary conversion circuit, and the second secondary conversion circuit, the charging mode switching between different ports is achieved.

[0052] For example, a matrix rectifier bridge allows bidirectional power flow, and the resonant network matches the switching frequency through the LC resonant frequency to achieve zero-voltage switching or zero-current switching, thereby improving efficiency. The matrix rectifier bridge consists of four switching tubes, with the first AC side connected to the first port and the second AC side connected to the primary side of the first transformer through a resonant network. The switching tubes are controlled by PWM to achieve the functions of rectifying AC-DC or inverting DC-AC. The resonant network is used for soft switching to reduce switching losses. It should also be noted that the rectangular rectifier bridge can be replaced with a full-bridge rectifier bridge, but additional switching tubes are required; or a bridgeless PFC circuit can be used to reduce conduction losses. In this way, bidirectional energy transmission improves transmission efficiency, and the resonant network reduces filtering interference. At the same time, the number of components is reduced, reducing costs.

[0053] For example, by adjusting the primary voltage of the transformer to zero, the magnetic flux change is blocked, thereby preventing energy transfer. When power is transmitted between the first port and the second port, the switch tube of the second secondary conversion circuit is controlled to be fully turned on, so that the primary side of the second transformer is short-circuited, thereby preventing energy from flowing to the third port; when power is transmitted between the second port and the third port, the switch tube of the first secondary conversion circuit is controlled to be fully turned on, so that the first transformer is short-circuited, thereby preventing energy from flowing back to the first port.

[0054] Through the above approach, by utilizing transformer design and conversion circuit topology selection, efficient power conversion from AC to HVDC and LVDC is achieved. Based on the timing control signals received from different switching tubes, the charging mode is determined and switched in real time, improving the flexibility and adaptability of the circuit and ensuring stable operation under various working conditions.

[0055] In some embodiments, the matrix rectifier bridge includes a first bridge arm and a second bridge arm, the first bridge arm and the second bridge arm constitute a full-bridge structure, and the upper bridge arm and the lower bridge arm of each bridge arm are composed of at least one group of switching tubes with opposite polarity, and each group is composed of switching tubes with opposite polarity to form a back-to-back switch; for example, a back-to-back switch can be selected to form the upper bridge arm and a back-to-back switch can be selected to form the lower bridge arm; of course, two back-to-back switches can also be connected in parallel to form the upper bridge arm and the lower bridge arm respectively.

[0056] Specifically, see Figure 1 In the embodiment, the upper bridge arm of the first bridge arm is composed of a first switching tube S1a and a second switching tube S1b with opposite polarities, and the lower bridge arm of the first bridge arm is composed of a third switching tube S2a and a fourth switching tube S2b with opposite polarities; the upper bridge arm of the second bridge arm is composed of a fifth switching tube S3a and a sixth switching tube S3b with opposite polarities, and the lower bridge arm of the second bridge arm is composed of a seventh switching tube S3a and an eighth switching tube S4b with opposite polarities.

[0057] It should be noted that the switch tubes of this application are all PMOS tubes, and are connected in a back-to-back manner so that their drains are directly connected to form a common drain structure. During the operation of the circuit, according to the input signal and the control strategy, the gate voltages of the two switches are controlled separately so that they switch in different working states, thereby realizing the regulation of the circuit current and voltage; since the drains are directly connected, this structure can effectively improve the voltage tolerance of the switching circuit, and during the switching process, the switching loss can be reduced by reasonable control timing; in addition, the back-to-back connection method has an inhibitory effect on electromagnetic interference to a certain extent, because the electric field and magnetic field distributions of the two switches affect each other, reducing the electromagnetic energy radiated outward. In addition, this control method can also effectively be compatible with the control of bidirectional gallium nitride switches.

[0058] The matrix bridge rectifier, based on the principle of a full-bridge circuit topology, utilizes a combination of opposite-polarity switches in each bridge arm to flexibly control the direction and magnitude of the AC input current. This combination of opposite-polarity switches dynamically adjusts the current path based on the phase and amplitude of the input AC power, enabling not only conventional rectification but also reverse energy flow when needed, achieving energy feedback. During the on- and off-state of the switches, a rational control strategy reduces switching losses, improves rectification efficiency, reduces harmonic generation, and improves power quality. It should be noted that the switches can be replaced with other types of power semiconductor devices, such as insulated-gate bipolar transistors (IGBTs) and metal-oxide-semiconductor field-effect transistors (MOSFETs), of varying models or performance. Different devices vary in on-resistance, switching speed, and voltage withstand capability. Choosing the appropriate device can optimize bridge rectifier performance based on actual application requirements, such as power level and operating frequency.

[0059] Through the above method, by precisely controlling the switches with opposite polarities, the current path is optimized, the conduction loss and switching loss are reduced, the rectification efficiency is improved, and the power conversion efficiency is significantly improved compared to the traditional rectifier bridge. For example, the switch tube combination structure enables the rectifier bridge to have the ability of bidirectional flow of electric energy. In some application scenarios that require energy feedback, such as electric vehicle braking energy recovery, renewable energy power generation systems, etc., excess electric energy can be fed back to the power grid or energy storage device, thereby improving energy utilization. In this way, the generation of harmonics is also effectively suppressed, the power factor is improved, the input current is made closer to a sine wave, and the harmonic pollution to the power grid is reduced. In addition, based on the control method of the switch tube, the rectifier output voltage and current can be flexibly adjusted to adapt to different load requirements, thereby enhancing applicability and compatibility.

[0060] In one embodiment, see Figure 2 The matrix rectifier bridge includes a first bridge arm and a second bridge arm, and the first bridge arm and the second bridge arm constitute a full-bridge structure. The upper bridge arm of the first bridge arm is a first bidirectional GaN device S1, and the lower bridge arm of the first bridge arm is a second bidirectional GaN device S2; the upper bridge arm of the second bridge arm is a third bidirectional GaN device S3, and the lower bridge arm of the second bridge arm is a fourth bidirectional GaN device S4.

[0061] Among them, in the full-bridge structure of the matrix rectifier bridge, the bidirectional GaN device can realize the bidirectional conductive function. When the AC input voltage is in the positive half cycle, the first bidirectional GaN device and the fourth bidirectional GaN device are turned on by controlling the drive signal, and the current forms a loop through these two devices to achieve rectification; when the AC input voltage is in the negative half cycle, the second bidirectional GaN device and the third bidirectional GaN device are controlled to be turned on to complete the rectification of the negative half cycle; due to the fast switching speed and low switching loss of the bidirectional GaN device, energy loss can be reduced during high-frequency switching; at the same time, its low on-resistance reduces conduction loss and improves the overall efficiency of the rectifier bridge. In addition, the high voltage resistance and high current density characteristics of GaN devices enable it to operate stably under high voltage and high current conditions, meeting the needs of high-power applications.

[0062] Specifically, if Figure 1 As shown, S1a and S1b can be replaced by a bidirectional GaN MOS. Figure 2 S1, S2a and S2b can be replaced by a bidirectional GaN MOS. Figure 2 S2, S3a and S3b can be replaced by a bidirectional GaN MOS. Figure 2 S3, S4a and S4b can be replaced by a bidirectional GaN MOS. Figure 2 In S4, the number of high-voltage switching tubes can be reduced from 14 to 10, further reducing the number of components, improving product power density and reducing costs.

[0063] In other embodiments, the matrix rectifier bridge includes a first bridge arm and a second bridge arm, the first bridge arm and the second bridge arm constitute a full-bridge structure, the upper bridge arm of the first bridge arm is a first bidirectional GaN device S1, and the lower bridge arm of the first bridge arm is a second bidirectional GaN device S2; the upper bridge arm of the second bridge arm is composed of a fifth switch tube S3a and a sixth switch tube S3b with opposite polarities, and the lower bridge arm of the second bridge arm is composed of a seventh switch tube S4a and an eighth switch tube S4b with opposite polarities, wherein the matrix rectifier bridge constructed in this way is not shown in the accompanying drawings.

[0064] For example, in the first bridge arm, switching and conduction losses can be significantly reduced, improving rectification efficiency and adapting to high-frequency operating scenarios. The second bridge arm, on the other hand, utilizes a combination of switching transistors with opposite polarity, leveraging their complementary conduction characteristics to operate alternately at different voltage polarities to achieve rectification. This combination leverages the performance advantages of GaN devices and the cost and technological maturity of traditional switching transistors. In a full-bridge structure, the two bridge arms work together to dynamically adjust the current path based on changes in the input AC phase and amplitude, achieving efficient conversion and transmission of electrical energy.

[0065] Among them, the two switches with opposite polarities have a back-to-back common drain structure, which will not be described in detail here.

[0066] Through the above method, through the back-to-back switching combination of bidirectional GaN devices and opposite polarity switching tubes, GaN devices are used in the first bridge arm to improve the efficiency, power density and high-frequency performance of the rectifier bridge, and traditional switching tubes are used in the second bridge arm to control costs, thereby achieving a good balance between performance and cost; the bidirectional GaN devices in the first bridge arm reduce the overall switching loss and conduction loss of the rectifier bridge, and improve the rectification efficiency; compared with traditional all-silicon-based rectifier bridges, in high-frequency working scenarios, it can not only improve stability and heat resistance, but also effectively reduce energy waste; through reasonable device selection and combination, combined with targeted heat dissipation and drive design, the risk of device damage due to overheating, excessive stress, etc. is reduced, and the reliability and service life of the rectifier bridge under complex working conditions are improved.

[0067] In some embodiments, a matrix rectifier bridge includes a first bridge arm and a second bridge arm, the first bridge arm and the second bridge arm constitute a full-bridge structure, the upper and lower bridge arms in the first bridge arm and the second bridge arm are composed of bidirectional GaN devices and back-to-back switches, and the back-to-back switches are composed of two switches with opposite polarities, wherein the matrix rectifier bridge constructed in this way is not shown in the attached figure.

[0068] The two switches with opposite polarity have a back-to-back common drain structure. The back-to-back switch, composed of two switches with opposite polarity, leverages their complementary conduction characteristics to achieve bidirectional current control and voltage isolation. When one switch is on, the other is off, switching the devices based on the current flow, ensuring smooth current flow. The connected drain structure enhances the switches' voltage resistance, effectively protecting them from sudden voltage changes or reverse voltage, and reducing the risk of damage. Furthermore, the back-to-back structure suppresses electromagnetic interference to a certain extent, improving the circuit's electromagnetic compatibility.

[0069] Through the above-mentioned approach, the combination of bidirectional GaN devices and back-to-back switches significantly reduces the switching and conduction losses of the rectifier bridge, improving the power conversion efficiency. At the same time, thanks to the high voltage resistance and high current density characteristics of the bidirectional GaN devices and the compact structural design of the back-to-back switches, the rectifier bridge can achieve higher power handling capabilities within a smaller volume. The wide voltage operating range of the bidirectional GaN devices and the flexible current control capabilities of the back-to-back switches enable the rectifier bridge to adapt to AC inputs of different voltage levels and diverse load requirements. The voltage isolation and overvoltage protection characteristics of the back-to-back switches, combined with the high reliability of the bidirectional GaN devices, enhance the rectifier bridge's anti-interference ability and stability under complex operating conditions. At the same time, the optimized heat dissipation design and control strategy reduce the risk of device overheating and damage, extend the service life of the rectifier bridge, and reduce maintenance costs and downtime. The back-to-back switch structure and reasonable circuit layout design effectively suppress the generation and propagation of electromagnetic interference.

[0070] In some embodiments, according to Figure 1 and Figure 2 The middle matrix rectifier bridge structure has the following corresponding drive signals: the drive signal of the first switching tube and the upper drive signal of the first bidirectional GaN device are the 1a drive signal, and the drive signal of the second switching tube and the lower drive signal of the first bidirectional GaN device are the 1b drive signal; the drive signal of the third switching tube and the upper drive signal of the second bidirectional GaN device are the 2a drive signal, and the drive signal of the fourth switching tube and the lower drive signal of the second bidirectional GaN device are the 2b drive signal; the drive signal of the fifth switching tube and the upper drive signal of the third bidirectional GaN device are the 3a drive signal, and the drive signal of the sixth switching tube and the lower drive signal of the third bidirectional GaN device are the 3b drive signal; the drive signal of the seventh switching tube and the upper drive signal of the fourth bidirectional GaN device are the 4a drive signal, and the drive signal of the eighth switching tube and the lower drive signal of the fourth bidirectional GaN device are the 4b drive signal.

[0071] In which, the first secondary side conversion circuit includes a third bridge arm and a fourth bridge arm, and the first transformer includes a second winding as a secondary coil, wherein the second winding is connected between the midpoint of the third bridge arm and the midpoint of the fourth bridge arm; the second primary side conversion circuit includes a fifth bridge arm and a shared fourth bridge arm, and the second transformer includes a third winding as a main coil, wherein the third winding is connected between the midpoint of the fourth bridge arm and the midpoint of the fifth bridge arm, and the two ends of the third bridge arm, the fourth bridge arm and the fifth bridge arm serve as the second port for connecting high-voltage direct current.

[0072] Specifically, the upper and lower bridge arms of the third bridge arm are the ninth switch tube and the tenth switch tube respectively, the upper and lower bridge arms of the fourth bridge arm are the eleventh switch tube and the twelfth switch tube respectively; the upper and lower bridge arms of the fifth bridge arm are the thirteenth switch tube and the fourteenth switch tube respectively, among which, the drive signals corresponding to the ninth switch tube, the tenth switch tube, the eleventh switch tube, the twelfth switch tube, the thirteenth switch tube and the fourteenth switch tube are the fifth drive signal, the sixth drive signal, the seventh drive signal, the eighth drive signal, the ninth drive signal and the tenth drive signal respectively.

[0073] In some embodiments, Figure 1 and Figure 2 The control mode of the charging control circuit includes at least one of the following:

[0074] In the first control mode, when the three-port forward terminal is operating, if the voltage at the first port is greater than zero, the 1a drive signal, the 2a drive signal, the 3a drive signal, and the 4a drive signal are continuously on signals, and the 1b drive signal and the 4b drive signal control the corresponding switch tubes to turn on and off at a preset duty cycle and a preset frequency, wherein the 4b drive signal lags behind the 1b drive signal by a first preset time, the 1b drive signal and the 2b drive signal are complementary, and the 3b drive signal and the 4b drive signal are complementary;

[0075] At the second port, based on the phase-shift control strategy, the 5th drive signal and the 8th drive signal control the corresponding switch tube to be turned on and off with a preset duty cycle and a preset frequency, and the 5th drive signal lags behind the 1b drive signal by a second preset time, and the 8th drive signal lags behind the 5th drive signal by a third preset time. By controlling the first secondary side conversion circuit, the AC voltage is rectified into a DC voltage, and power is transmitted to the second port; wherein, the 5th drive signal and the 6th drive signal, as well as the 7th drive signal and the 8th drive signal are complementary; at the same time, based on the phase-shift control strategy, the 9th drive signal controls the corresponding switch tube to be turned on and off with a preset duty cycle and a preset frequency, and the 9th drive signal leads or lags behind the 8th drive signal by a fourth preset time, wherein the 9th drive signal and the 10th drive signal are complementary.

[0076] In a second control mode, when the three-port forward terminal is operating, if the voltage at the first port is less than zero, the 1b drive signal, the 2b drive signal, the 3b drive signal, and the 4b drive signal are continuously on signals, and the 2a drive signal and the 3a drive signal control the corresponding switch tubes to turn on and off at a preset duty cycle and a preset frequency, wherein the 3a drive signal lags behind the 2a drive signal by a fifth preset time, the 1a drive signal and the 2a drive signal are complementary, and the 3a drive signal and the 4a drive signal are complementary;

[0077] At the second port, based on the phase-shift control strategy, the 5th drive signal and the 8th drive signal control the corresponding switch tube to be turned on and off with a preset duty cycle and a preset frequency, and the 5th drive signal lags behind the 2a drive signal by a sixth preset time, and the 8th drive signal lags behind the 5th drive signal by a seventh preset time. By controlling the first secondary side conversion circuit, the AC voltage is rectified into a DC voltage, and power is transmitted to the second port; wherein, the 5th drive signal and the 6th drive signal, as well as the 7th drive signal and the 8th drive signal are complementary; at the same time, based on the phase-shift control strategy, the 9th drive signal controls the corresponding switch tube to be turned on and off with a preset duty cycle and a preset frequency, and the 9th drive signal leads or lags behind the 8th drive signal by an eighth preset time, wherein the 9th drive signal and the 10th drive signal are complementary.

[0078] A third control mode is as follows: when the three-port forward terminal is operating, if the voltage at the first port is less than zero, the 1b drive signal, the 2b drive signal, the 3b drive signal, and the 4b drive signal are continuously on signals, and the 2a drive signal and the 3a drive signal control the corresponding switch tubes to turn on and off at a preset duty cycle and a preset frequency, wherein the 2a drive signal lags behind the 3a drive signal by a fifth preset time, the 1a drive signal and the 2a drive signal are complementary, and the 3a drive signal and the 4a drive signal are complementary;

[0079] At the second port, based on the phase-shift control strategy, the 5th drive signal and the 8th drive signal control the corresponding switch tube to be turned on and off with a preset duty cycle and a preset frequency, and the 5th drive signal lags behind the 3a drive signal by a sixth preset time, and the 8th drive signal lags behind the 5th drive signal by a seventh preset time. By controlling the first secondary side conversion circuit, the AC voltage is rectified into a DC voltage, and power is transmitted to the second port; wherein, the 5th drive signal and the 6th drive signal, as well as the 7th drive signal and the 8th drive signal are complementary; at the same time, based on the phase-shift control strategy, the 9th drive signal controls the corresponding switch tube to be turned on and off with a preset duty cycle and a preset frequency, and the 9th drive signal leads or lags behind the 8th drive signal by an eighth preset time, wherein the 9th drive signal and the 10th drive signal are complementary.

[0080] When operating in the forward three-port mode, if the AC voltage is greater than 0, there is one control method; if the AC voltage is less than 0, there are two control methods. In a matrix rectifier bridge, swapping the upper and lower arms of the same bridge evenly distributes the switching losses of the upper and lower switches. Swapping the left and right arms between two bridge arms evenly distributes the switching losses of the left and right arms, making this design more conducive to heat dissipation. Using the first control method alone in conjunction with the second control method concentrates the heat of the switching tube in the first arm. Using both the first and third control methods, periodically combining the first control method with the second and third control methods can significantly reduce the heat of the switching tube and ensure even distribution of the switching tube losses.

[0081] It should be noted that this control method is compatible with bidirectional GaN devices and back-to-back switches to form a matrix rectifier bridge, which will not be described in detail here.

[0082] Through the above-described method, precise drive signal control and phase-shift control strategies are used to optimize the switching timing of power devices in the circuit, effectively reducing switching and conduction losses and improving energy conversion efficiency. Compared to traditional control strategies, this method improves power conversion efficiency, reduces energy waste, and increases energy utilization, especially under the same operating conditions. By rationally setting the timing, phase difference, and complementary relationship between the various drive signals, current balance and voltage stability are ensured under different operating conditions. This effectively suppresses voltage fluctuations and current imbalances, enhances the system's anti-interference capability, improves system reliability and stability, and extends the service life of the equipment. Through flexible allocation and efficient transmission between the three ports, drive signal parameters can be dynamically adjusted according to the load requirements of different ports, rationally distributing energy to meet the power requirements of various application scenarios, improving the system's applicability and versatility. Furthermore, the optimized drive signal control method reduces the high-frequency harmonics generated during the switching of power devices, reducing electromagnetic interference levels.

[0083] A fourth control mode, in reverse three-port operation, if the voltage of the first port is greater than zero, the 1a drive signal, the 2a drive signal, the 3a drive signal, and the 4a drive signal are continuously on signals; based on the phase-shift control strategy, the 5th drive signal and the 8th drive signal control the corresponding switch tubes to turn on and off at a preset duty cycle and a preset frequency, and the 8th drive signal lags behind the 5th drive signal by a first preset time, thereby inverting the DC voltage into an AC voltage, wherein the 5th drive signal and the 6th drive signal, as well as the 7th drive signal and the 8th drive signal, are complementary;

[0084] The 1b drive signal and the 4b drive signal control the corresponding switch tubes to turn on and off with a preset duty cycle and a preset frequency, and the 1b drive signal lags behind the 5th drive signal by a second preset time, and the 4b drive signal lags behind the 1b drive signal by a third preset time, so that the AC voltage transmits power to the first port, wherein the 1b drive signal is complementary to the 2b drive signal, and the 3b drive signal is complementary to the 4b drive signal.

[0085] A fifth control mode, in reverse three-port operation, if the voltage at the first port is less than zero, the 1b drive signal, the 2b drive signal, the 3b drive signal, and the 4b drive signal are continuously on signals, and the 5th drive signal and the 8th drive signal control the corresponding switch tubes to turn on and off at a preset duty cycle and a preset frequency based on the phase-shift control strategy, and the 8th drive signal lags behind the 5th drive signal by a fifth preset time; the DC voltage is inverted into an AC voltage, wherein the 5th drive signal and the 6th drive signal, as well as the 7th drive signal and the 8th drive signal, are complementary;

[0086] The 2a drive signal and the 3a drive signal control the corresponding switch tube to turn on and off with a preset duty cycle and a preset frequency, and the 2a drive signal lags behind the 5th drive signal by a sixth preset time, and the 3a drive signal lags behind the 2a drive signal by a seventh preset time, so that the AC voltage transmits power to the first port, wherein the 1a drive signal and the 2a drive signal are complementary to each other, and the 3a drive signal and the 4a drive signal are complementary to each other.

[0087] A sixth control mode, in reverse three-port operation, if the voltage at the first port is less than zero, the 1b drive signal, the 2b drive signal, the 3b drive signal, and the 4b drive signal are continuously on signals, and the 5th drive signal and the 8th drive signal control the corresponding switch tubes to turn on and off at a preset duty cycle and a preset frequency based on the phase-shift control strategy, and the 8th drive signal lags behind the 5th drive signal by a fifth preset time; the DC voltage is inverted into an AC voltage, wherein the 5th drive signal and the 6th drive signal, as well as the 7th drive signal and the 8th drive signal, are complementary;

[0088] The 2a drive signal and the 3a drive signal control the corresponding switch tube to turn on and off with a preset duty cycle and a preset frequency, and the 3a drive signal lags behind the 5th drive signal by a sixth preset time, and the 2a drive signal lags behind the 3a drive signal by a seventh preset time, so that the AC voltage transmits power to the first port, wherein the 1a drive signal and the 2a drive signal are complementary to each other, and the 3a drive signal and the 4a drive signal are complementary to each other.

[0089] When operating in reverse three-port mode, one control mode exists when the AC voltage is greater than 0, and two control modes exist when the AC voltage is less than 0. In a matrix rectifier bridge, swapping the upper and lower arms of the same bridge evenly distributes the switching losses of the upper and lower switches. Swapping the left and right arms between two bridge arms evenly distributes the switching losses of the left and right arms, making this design more conducive to heat dissipation. Using the fourth control mode in conjunction with the fifth control mode alone concentrates the heat of the switching tube in the first bridge arm. Using the fourth control mode in conjunction with the sixth control mode simultaneously, the fourth control mode, periodically combined with the fifth and sixth control modes, significantly reduces the heat of the switching tube and ensures even distribution of the switching tube losses.

[0090] It should be noted that this control method is compatible with bidirectional GaN devices and back-to-back switches to form a matrix rectifier bridge, which will not be described in detail here.

[0091] Through precise drive signal control and phase-shift control strategies, energy loss during reverse three-port operation is effectively reduced, significantly improving power conversion efficiency. Compared to traditional solutions, under the same operating conditions, this improves energy conversion efficiency and enables efficient transmission and utilization of reverse energy. Reasonable drive signal timing and complementary conduction design effectively suppress circuit oscillations and voltage and current fluctuations, enhancing the system's stability and reliability in reverse operating mode. Even under complex operating conditions where the first-port voltage is less than zero, the system maintains continuous and stable operation, extending the device's service life.

[0092] Through flexible reverse distribution among the three ports, the drive signal parameters can be dynamically adjusted according to the load requirements of different ports, and energy can be reasonably distributed to meet the power requirements in various application scenarios, thereby improving the applicability and versatility of the system. At the same time, the optimized drive signal control method reduces the high-frequency harmonics generated during the switching process of the power device and reduces the level of electromagnetic interference.

[0093] A seventh control mode, when a single low-voltage DCDC is operating, the 1a, 1b, 2a, 2b, 3a, 3b, 4a, and 4b drive signals are shutdown signals, and phase-shifted full-bridge control or variable duty cycle control is performed on the three bridge arms and the fourth bridge arm. The 5th and 7th drive signals control the corresponding switching tubes to be synchronously turned on and off, and the 6th and 8th drive signals control the corresponding switching tubes to be synchronously turned on and off, so that the voltage between the third and fourth bridge arms approaches zero.

[0094] Among them, when the low-voltage DCDC is working in step-down mode alone, the voltage duty cycle of the midpoint of the fourth bridge arm and the fifth bridge arm or the operating duty cycle of the switch tube in the fourth bridge arm and the fifth bridge arm is adjusted, and the high-voltage DC voltage is converted into a low-voltage DC voltage through synchronous rectification, and power is transmitted to the third port; or, when the low-voltage DCDC is working in step-up mode alone, whether the second primary side conversion circuit performs synchronous rectification is controlled to convert the low-voltage DC voltage into a high-voltage DC voltage, and power is transmitted to the second port.

[0095] Exemplarily, when a low-voltage DC-DC converter is in boost operation alone, the switch in the first primary-side conversion circuit is turned off, the duty cycle of the switch in the second secondary-side conversion circuit is adjusted, and whether the second primary-side conversion circuit performs synchronous rectification, that is, rectification or non-rectification, is controlled to convert the low-voltage DC voltage into a high-voltage DC voltage, and transmit power to the second port.

[0096] Additionally, the following control methods are included:

[0097] When operating in the forward high voltage direction alone, the operating frequencies of the switches in the first primary conversion circuit and the first secondary conversion circuit are controlled, the voltage duty ratio of the midpoint of the bridge arm between the first primary conversion circuit and the first secondary conversion circuit, and the voltage phase of the midpoint of the bridge arm between the first primary conversion circuit and the first secondary conversion circuit are adjusted, the AC voltage is rectified into a DC voltage, and power is transmitted to the second port;

[0098] When working in reverse AC mode alone, the switch tube in the second secondary conversion circuit is turned off, the operating frequency of the switch tubes in the first primary conversion circuit and the first secondary conversion circuit is controlled, the voltage duty ratio of the midpoint of the bridge arm between the first primary conversion circuit and the first secondary conversion circuit, and the voltage phase of the midpoint of the bridge arm between the first primary conversion circuit and the first secondary conversion circuit are adjusted, the DC voltage is inverted into an AC voltage, and power is transmitted to the first port.

[0099] Specifically, the above-mentioned multiple operating modes correspond to the following multiple situations. For example, in the first situation, the AC port transmits power to the HVDC port, and the LVDC port is unloaded. For details, see the first, second, and third control modes mentioned above; in the second situation, the AC port transmits power to the HVDC and LVDC ports simultaneously; in the third situation, the HVDC port transmits power to the AC port, and the LVDC port is unloaded. For details, see the fourth, fifth, and sixth control modes mentioned above; in the fourth situation, the HVDC port transmits power to the LVDC port, and the AC port is unloaded. For details, see part of the seventh control mode mentioned above; in the fifth situation, the HVDC port transmits power to the AC and LVDC ports simultaneously; in the sixth situation, the LVDC port transmits power to the HVDC port, and the AC port is unloaded. For details, see part of the seventh control mode mentioned above.

[0100] For example, the switching tubes in the matrix rectifier bridge include but are not limited to bidirectional GaN devices, IGBTs, MOSFETs and other different model combinations to realize the functions of the switching tubes; different control algorithms can also be used, such as PI control, fuzzy control, etc. to adjust the voltage duty cycle and phase.

[0101] For example, during standalone low-voltage DC-DC step-down operation, after the switches in the first primary-side conversion circuit are turned off, the transmission path from the high-voltage DC to the first port is cut off. Conversion from high-voltage DC to low-voltage DC is achieved solely by adjusting the parameters of the second primary-side conversion circuit. For example, the switches in the first primary-side conversion circuit are turned off; the voltage duty cycle at the midpoint of the bridge arm of the second primary-side conversion circuit is adjusted, or the operating duty cycle of the switches in the second primary-side conversion circuit is adjusted, to control the second secondary-side conversion circuit to perform synchronous rectification, converting the high-voltage DC voltage to a low-voltage DC voltage, and transmitting power to the third port.

[0102] For example, during standalone low-voltage DC-DC boost operation, after the switch in the first primary-side conversion circuit is turned off, the parameters of the second primary-side conversion circuit are adjusted to achieve low-voltage DC to high-voltage DC conversion, prioritizing the stability of the low-voltage DC input and the accuracy of the high-voltage DC output. For example, the switch in the first primary-side conversion circuit is turned off, and the duty cycle of the switch in the second secondary-side conversion circuit is adjusted to control whether the second primary-side conversion circuit performs synchronous rectification, i.e., whether it rectifies or not, to convert the low-voltage DC voltage into a high-voltage DC voltage and transmit power to the second port.

[0103] Specifically, a filter circuit can be added to improve the quality of the low-voltage DC output; digital control technology can also be used to accurately adjust the voltage duty cycle; a step-up transformer can also be used to assist in the conversion of low-voltage DC to high-voltage DC; and more advanced control algorithms can also be used to improve conversion efficiency.

[0104] Illustratively, during single forward high-voltage operation, efficient and stable AC-DC power conversion is achieved by controlling the operating frequency, voltage duty cycle, and phase of the switching tube, and power is transmitted to the second port. For example, the operating frequency of the switching tubes in the first primary conversion circuit and the first secondary conversion circuit is controlled, and the voltage duty cycle and voltage phase of the midpoints of the bridge arms between the first primary conversion circuit and the first secondary conversion circuit are adjusted to rectify the AC voltage into a DC voltage, and transmit power to the second port.

[0105] In this embodiment, high efficiency is achieved across the full load range through coordinated optimization of frequency, duty cycle, and phase; power is transmitted only to the second port to ensure that the power battery of the high-voltage load can be charged first to meet different usage scenarios.

[0106] For example, when operating in reverse AC mode, the low-voltage DC output path is disconnected, and the DC-to-AC inversion function is achieved by controlling the switches in the first primary and secondary conversion circuits. For example, the switches in the second secondary conversion circuit are turned off; the operating frequencies of the switches in the first primary and second secondary conversion circuits are controlled, and the voltage duty cycle and voltage phase at the midpoint of the bridge arms of the first primary and second secondary conversion circuits are adjusted to invert the DC voltage into an AC voltage, transmitting power to the first port.

[0107] Specifically, multi-level inverter technology can be used to improve the waveform quality of the AC output; intelligent control strategies can also be used to adapt to different load changes.

[0108] In this embodiment, the focus is on inverting the DC voltage into an AC voltage to provide a stable AC power supply for devices that require AC power.

[0109] In the above manner, by switching modes among forward three-port operation, reverse three-port operation, separate low-voltage DCDC step-down operation, separate low-voltage DCDC step-up operation, separate forward high-voltage operation or separate reverse AC operation, the needs of different application scenarios are met, and the power conversion efficiency is improved by precisely controlling the switch and optimizing the circuit structure.

[0110] In some embodiments, the resonant network includes a first resonant inductor, a first resonant capacitor and an excitation inductor. The midpoint of the first bridge arm is connected to the same-name end of the first winding in the first transformer through the first resonant inductor, and the midpoint of the second bridge arm is connected to the opposite-name end of the first winding in the first transformer through the first resonant capacitor. The excitation inductor is connected in parallel at both ends of the first winding to form a resonant network with the first resonant inductor and the first resonant capacitor.

[0111] For example, the resonant network uses the resonant characteristics of inductors and capacitors to achieve efficient energy transfer at a specific frequency. The switch tube in the bridge arm controls the input and output of energy through high-frequency switching action to achieve DC-AC or AC-DC conversion. The resonant network can be L, LC, LLC, CLC, CLLC or CLLLC, etc. The resonant inductor stores electrical energy and releases energy when the switch tube is turned off to maintain the current flow in the circuit. The resonant capacitor cooperates with the inductor to form an LC oscillation circuit to achieve periodic energy conversion. The excitation inductor plays a role in stabilizing the voltage and current in the circuit, improving the circuit's anti-disturbance ability. The drive circuit provides sufficient drive voltage and current to ensure that the switch tube can be reliably turned on and off. By adjusting the switching timing of the switch tube, it is switched under zero voltage or zero current conditions, reducing the loss of the switch tube.

[0112] Specifically, the first primary-side conversion circuit includes selecting and installing switching tubes, such as MOSFETs or IGBTs, for the first and second bridge arms, a first resonant inductor, a first resonant capacitor, and an excitation inductor, ensuring that the midpoint of the first bridge arm is sequentially connected to the first resonant inductor, the same-name end of the first winding, the first resonant capacitor, and then to the midpoint of the second bridge arm to form a series circuit; the excitation inductor is connected in parallel to the two ends of the first winding to form a resonant network with the first resonant inductor and the first resonant capacitor. When the switching tube switches at a specific frequency, the inductor and capacitor in the resonant network will resonate, forming an oscillating current; by controlling the duty cycle and switching frequency of the switching tube, the output voltage and current of the resonant network can be adjusted to ensure that the switching tube switches according to the predetermined frequency and duty cycle, thereby achieving soft switching control of the switching tube and reducing losses and electromagnetic interference during the switching process.

[0113] Through the above method, by optimizing the resonant network and the switch tube, efficient energy conversion and transmission can be achieved, and the voltage stabilizing effect of the resonant network can be utilized to achieve a stable output voltage, thereby improving the reliability and stability of the circuit.

[0114] In some embodiments, the first secondary side conversion circuit includes a third bridge arm, a fourth bridge arm and a second resonant capacitor, the midpoint of the third bridge arm is connected in series with the second resonant capacitor, the same-name end of the second winding and the midpoint of the fourth bridge arm, wherein the second winding is connected between the midpoint of the third bridge arm and the midpoint of the fourth bridge arm.

[0115] For example, the third and fourth bridge arms undergo switching actions through the switching tubes. When the third and fourth bridge arms are switched on and off according to a specific timing sequence, the direction and magnitude of the current in the circuit change. The resonant capacitor, together with the bridge arms and windings, forms a complex resonant network that modulates and filters the current, helping to smooth the current waveform, reduce harmonic content, and improve power quality.

[0116] Through the above method, by optimizing the circuit design and introducing the resonant network, energy loss is reduced and conversion efficiency is improved; the second winding realizes the output of multiple different voltages or currents through the connection of different sub-windings and the switching control of the bridge arm; the introduction of the resonant capacitor improves the resonance characteristics of the circuit and improves the power quality and stability.

[0117] In some embodiments, the second primary side conversion circuit includes a fourth bridge arm and a fifth bridge arm, the fourth bridge arm is a common bridge arm, and the second transformer includes a third winding as the main coil, wherein the third winding is connected between the midpoint of the fourth bridge arm and the midpoint of the fifth bridge arm, and the two ends of the third bridge arm, the fourth bridge arm and the fifth bridge arm serve as the second port for connecting high voltage direct current.

[0118] Exemplarily, the like-name end of the third winding is connected to the midpoint of the fourth bridge arm, and the opposite-name end of the third winding is connected to the midpoint of the fifth bridge arm through the second resonant inductor. The second resonant inductor is added to the circuit to form a resonant network with the bridge arm; through the combination of multiple bridge arms and resonant elements, the efficiency and stability of the primary side conversion circuit are improved. At the same time, the design of the resonant network helps to optimize the performance of the circuit and reduce energy loss.

[0119] In the above manner, by optimizing the circuit structure and the design of the resonant network, energy loss is reduced and the primary side conversion efficiency is improved. By rationally configuring the resonant inductor, the circuit performance is improved and the harmonic content is reduced.

[0120] In some embodiments, the second secondary side conversion circuit includes a first synchronous rectification network, a second synchronous rectification network, a first clamping loop, a second clamping loop, an output capacitor, and an output inductor; the second transformer includes a positive winding segment n4 and a negative winding segment n5 as a secondary coil;

[0121] The first clamping loop is connected in parallel at both ends of the first synchronous rectification network, and the second clamping loop is connected in parallel at both ends of the second synchronous rectification network; the opposite-name end of the positive winding segment and the same-name end of the negative winding segment are connected in sequence, the same-name end of the positive winding segment is connected to the negative pole of the third port through the second synchronous rectification network, and the opposite-name end of the negative winding segment is connected to the negative pole of the third port through the first synchronous rectification network; the midpoint of the positive winding segment and the negative winding segment is connected to the positive pole of the third port through the output inductor, and the output capacitor is connected between the positive pole and the negative pole of the third port.

[0122] Optionally, the first clamping loop includes a thirteenth switch tube, a first freewheeling diode, and a first capacitor, wherein the anode of the first freewheeling diode is connected to the input end of the thirteenth switch tube, the cathode of the first freewheeling diode is connected to the output end of the thirteenth switch tube, and the output end of the thirteenth switch tube is connected to the cathode of the third port via the first capacitor;

[0123] The second clamping loop includes a fourteenth switch tube, a second freewheeling diode and a second capacitor, the positive electrode of the second freewheeling diode is connected to the input end of the fourteenth switch tube, the negative electrode of the second freewheeling diode is connected to the output end of the fourteenth switch tube, and the output end of the fourteenth switch tube is connected to the negative electrode of the third port through the second capacitor.

[0124] Optionally, the first synchronous rectification network and the second synchronous rectification network are the eleventh switch tube and the twelfth switch tube respectively, the thirteenth switch tube and the eleventh switch tube are complementary turned on, and the fourteenth switch tube and the twelfth switch tube are complementary turned on.

[0125] Exemplarily, the synchronous rectification network uses a MOSFET or other semiconductor device with low on-resistance to replace the traditional rectifier diode, reducing energy loss during the rectification process and improving conversion efficiency; the fourth winding is electromagnetically coupled through the series sub-windings, wherein the output capacitor is used to smooth the output voltage and reduce voltage fluctuations; the output inductor is connected to the midpoint of the series sub-windings to form an LC filter network for stabilizing the output voltage; the on-resistance of the synchronous rectification device is much lower than that of the traditional rectifier diode, reducing energy loss during the rectification process; by precisely controlling the switching action of the synchronous rectification device, efficient power conversion can be achieved; the output capacitor is used to smooth the output voltage, reduce voltage fluctuations, and improve the stability of the output voltage; the output inductor is connected to the midpoint of the series sub-windings to form an LC filter network for filtering out high-frequency noise and ripple and stabilizing the output voltage.

[0126] Through the above method, by adopting a synchronous rectification network, the energy loss in the rectification process is significantly reduced and the conversion efficiency is improved; through the application of output capacitors and output inductors, an effective filtering network is formed to ensure the stability of the output voltage; through reasonable circuit design and component selection, the number of unnecessary components is reduced, and the cost and complexity of the circuit are reduced.

[0127] Specifically, the second secondary side conversion circuit further includes a first clamping loop connected in parallel at both ends of the first synchronous rectification network, and a second clamping loop connected in parallel at both ends of the second synchronous rectification network.

[0128] For example, when an overvoltage exists across the synchronous rectification network, the clamping diode conducts, and a clamping resistor, or a combination of a clamping diode and a Zener diode, directs the overvoltage to a clamping capacitor, or a resistor-capacitor combination, for absorption and buffering. The clamping capacitor stores and releases energy, smoothing the overvoltage waveform and reducing its impact on the synchronous rectification device. The second clamping circuit operates on the same principle as the first clamping circuit. The clamping diode and clamping capacitor absorb and buffer the overvoltage, providing an additional protective barrier for the second synchronous rectification network and enhancing circuit reliability.

[0129] In the above manner, by connecting the clamping circuit in parallel at both ends of the first synchronous rectification network and the second synchronous rectification network, the synchronous rectification device is effectively protected from damage by overvoltage, thereby extending the service life of the device; the existence of the clamping circuit absorbs overvoltage and transient voltage fluctuations, improves the overall stability of the circuit, and reduces the occurrence of faults and abnormal conditions. The clamping circuit serves as an additional protective barrier, enhancing the reliability of the circuit, so that the circuit can still maintain normal operation under harsh working conditions and abnormal conditions.

[0130] In some embodiments, the first synchronous rectification network is a first switching tube, the first clamping loop is a second switching tube, the second synchronous rectification network is a third switching tube, the first clamping loop is a fourth switching tube, the first switching tube and the second switching tube are complementary conductive, and the third switching tube and the fourth switching tube are complementary conductive.

[0131] For example, the first switch tube usually adopts a semiconductor device with low on-resistance to achieve efficient power conversion. The second switch tube serves as a clamping switch and includes a clamping diode for absorbing and buffering overvoltage. The complementary conduction mechanism is implemented through a control circuit to ensure that the two switch tubes are not turned on at the same time, thereby avoiding short circuit and energy loss. The design of the third switch tube and the fourth switch tube is similar to that of the first switch tube and the second switch tube, adopting semiconductor devices with low on-resistance and clamping protection elements. The complementary conduction mechanism is also implemented through a control circuit to ensure that the two switch tubes are not turned on at the same time.

[0132] Through the above-mentioned method, the design of the first switch tube and the third switch tube achieves efficient power conversion and control, thereby improving the conversion efficiency of the entire circuit; the second switch tube and the fourth switch tube serve as switches corresponding to the clamping loop, providing effective overvoltage protection, preventing damage to circuit components, and enhancing circuit stability; the complementary conduction design makes the circuit more flexible and can adapt to different application requirements and working conditions. Through innovative circuit design, the circuit structure is simplified, the number of components is reduced, the cost is reduced, and the reliability is improved.

[0133] In some embodiments, the second clamping loop further includes a first freewheeling diode connected in parallel at both ends of the second switch tube, and a second freewheeling diode connected in parallel at both ends of the fourth switch tube.

[0134] For example, the freewheeling diode has unidirectional conductivity. When the current in the circuit suddenly decreases, the freewheeling diode provides a low-impedance path, allowing the energy in the inductor to be released as current through the freewheeling diode, thereby preventing the impact of sudden current changes and reverse electromotive force on circuit components. Under the action of forward voltage, the freewheeling diode conducts, allowing current to pass; under the action of reverse voltage, the freewheeling diode cuts off, preventing the current from flowing in the opposite direction. The function of the second freewheeling diode is the same as that of the first freewheeling diode, also to solve the problems of sudden current changes and reverse electromotive force. When the fourth switch tube is disconnected, the second freewheeling diode provides a low-impedance path, allowing the energy in the inductor to be released, protecting the circuit components.

[0135] In the above manner, by connecting freewheeling diodes in parallel in the first clamping loop and the second clamping loop respectively, the switching elements and other vulnerable elements in the circuit are fully protected, thereby extending the service life of the circuit; effectively solving the problems of current mutation and reverse electromotive force, improving the stability and reliability of the circuit, and reducing the failure rate; reducing energy loss, improving the overall efficiency of the circuit, and reducing operating costs.

[0136] In some embodiments, the first clamping loop further includes a first capacitor connected in series between the second switch tube and the cathode of the third port; and a second capacitor connected in series between the fourth switch tube and the cathode of the third port.

[0137] For example, capacitors have the ability to store charge and energy and can act as filters in circuits. When voltage fluctuations or ripples occur in a circuit, capacitors can absorb and release charge, thereby smoothing the voltage fluctuations and reducing the ripples.

[0138] Adding a capacitor in series with the clamping loop enhances the circuit's filtering effect and improves output signal stability. The second capacitor serves the same purpose as the first capacitor: to address voltage fluctuations and ripple, improving circuit stability. Adding a second capacitor in series with the clamping loop further enhances the filtering effect of the circuit associated with the second synchronous rectification network.

[0139] In the above manner, by connecting capacitors in series in the clamping loop, the voltage fluctuation and ripple in the circuit are effectively reduced, and the stability and performance of the circuit are improved; the series capacitors enhance the filtering capability of the circuit, improve the quality of the output signal, making it smoother and more stable, and at the same time reduce the impact of voltage fluctuations and ripples on circuit components, extend the service life of the circuit, and improve the reliability of the circuit.

[0140] The present application provides a vehicle-mounted charger, comprising the above-mentioned charging control circuit.

[0141] Exemplarily, the memory in the on-board charging control system stores preset control instructions. According to the control instructions, the on-board charger is controlled to switch the usage mode. The control system can switch between forward three-port operation, reverse three-port operation, independent low-voltage DCDC step-down operation, independent low-voltage DCDC step-up operation, independent forward high-voltage operation or independent reverse AC operation.

[0142] For example, the user can manually adjust the mode or adjust the usage mode through the controller according to the control instructions. For example, the user can manually adjust the mode intuitively through the user interface, which improves the convenience of operation and user experience. At the same time, the control automatically switches the usage mode of the on-board charger according to the preset control instructions in the memory, realizing intelligent charging management.

[0143] The present application provides a new energy vehicle, comprising the above-mentioned on-board charger.

[0144] Exemplarily, a new energy vehicle includes a high-voltage battery, an on-board charger and a low-voltage battery. The input end of the on-board charger is connected to the AC port, and the output end HVDC of the on-board charger is connected to the high-voltage battery. The high-voltage battery can also serve as an input end and be connected to the low-voltage battery through LVDC.

[0145] See Figure 1 , is an efficient integrated on-board charger circuit topology that integrates AC-DC, HVDC, and LVDC circuits, including two transformers T1 and T2 and three ports of AC, HVDC, and LVDC;

[0146] The first transformer T1 includes a magnetic core of the first transformer T1, a first winding n1 on the AC port side, and a second winding n2 on the HVDC port side.

[0147] The second transformer T2 includes a magnetic core of the second transformer T2, a HVDC port side third winding n3, a LVDC port side fourth winding n4 (ie, a positive winding section) and a LVDC port side winding n5 (ie, a negative winding section).

[0148] The AC port is connected to the AC grid or AC load, the HVDC port is connected to the on-board high-voltage battery or high-voltage load, and the LVDC port is connected to the on-board low-voltage battery.

[0149] The AC port circuit includes switches S1a, S1b, S2a, S2b, S3a, S3b, S4a, and S4b. S1a, S1b, S2a, and S2b form the first bridge arm, while S3a, S3b, S4a, and S4b form the second bridge arm. The midpoint of the first bridge arm is connected in series to inductor Lr and the same-name terminals of the first winding n1 of the first transformer. The midpoint of the second bridge arm is connected in series with capacitor Cr1 and the opposite-name terminals of the first winding n1. The magnetizing inductor Lm is connected in parallel across the first winding n1. Lr, Cr1, and the magnetizing inductor Lm form a resonant network.

[0150] The HVDC port circuit includes switches S5, S6, S7, S8, S9, and S10. S5 and S6 form the third bridge arm, S7 and S8 form the fourth bridge arm, and S9 and S10 form the fifth bridge arm. The midpoint of the third bridge arm is connected to the same-name terminals of the second winding n2 via capacitor Cr2. The midpoint of the fourth bridge arm is connected in series with the same-name terminals of the third winding n3 of the second transformer and the opposite-name terminals of the first winding n2 of the first transformer. The midpoint of the fifth bridge arm is connected in series with the inductor Ls, the opposite-name terminals of the third winding n3, and the opposite-name terminals of the second winding n2.

[0151] The LVDC port circuit includes switches S11, S12, S13, and S14. The positive winding segment n4 is connected to the negative winding segment n5. The same-name terminal of the positive winding segment n4 is connected to the switch S12, and the switch S14, diode D2, and capacitor C2 are connected in parallel to S12. The diode D2 is connected in parallel with the switch S14 and then in series with the capacitor C2. The opposite-name terminal of the negative winding segment n5 is connected to the switch S11, and the switch S11 is connected in parallel with the switch S13, diode D1, and capacitor C1. The diode D1 is connected in parallel with the switch S13 and then in series with the capacitor C1. The source electrodes of the switch S12 and the switch S11 are connected. The midpoint between the positive winding segment n4 and the negative winding segment n5 is connected to the output inductor Lo and the output capacitor Co, and is connected to the sources of the switch S12 and the switch S11, forming a series connection.

[0152] This application provides a control strategy applied to the above topology, which is detailed as follows:

[0153] When the AC port transmits power to the HVDC port, a control strategy of frequency conversion, phase shifting, or a combination of the two is adopted; when the HVDC port transmits power to the AC port, a control strategy of frequency conversion, phase shifting, or a combination of the two is adopted; when the HVDC port transmits power to the LVDC port, a control strategy of frequency conversion, phase shifting, or a combination of the two is adopted; when the LVDC port transmits power to the HVDC port, a control strategy of variable duty cycle is adopted.

[0154] The variable frequency control is manifested by changing the frequency of the switching tube. The phase shift control includes internal phase shift and external phase shift. Internal phase shift is manifested by changing the duty cycle of the output voltage between the midpoints of the two bridge arms on the AC port side (or the duty cycle of the output voltage between the midpoints of the three bridge arms on the HVDC port side), and external phase shift is manifested by changing the phase of the output voltage between the midpoints of the bridge arms of the AC port and the HVDC port. The variable duty cycle control is manifested by controlling the transmission power by changing the driving duty cycle of the switching tubes S11 and S12 in the LVDC port. At the same time, the switching tubes S13 and S11 are complementary to each other, the switching tube S14 and the switching tube S12 are complementary to each other, and the switching tubes S11 and S12 are synchronously rectified.

[0155] In forward three-port simultaneous operation, see Figure 3 , is a first timing control diagram corresponding to the switch of a charging control circuit provided by this application when the three forward ports work simultaneously, and power is transmitted from the AC port to the HVDC and LVDC ports simultaneously, as detailed below:

[0156] When the voltage of the AC port is greater than 0, the AC port switches S1a, S2a, S3a, and S4a are continuously turned on;

[0157] Switch S1b is turned on with a duty cycle of 50% and a frequency of fs;

[0158] The switch tube S4b is turned on with a duty cycle of 50% and a frequency of fs, and is turned on after the switch tube S1b is turned on for a first time Dt1;

[0159] The switch tube S2b and the switch tube S1b are complementary turned on, and the switch tube S3b and the switch tube S4b are complementary turned on;

[0160] The HVDC port switch S5 is turned on with a duty cycle of 50% and a frequency of fs, and is turned on after the switch S1b by a second time Dt2.

[0161] The switch S8 is turned on with a duty cycle of 50% and a frequency of fs, and its turn-on time lags behind the switch S5 by a third time Dt3;

[0162] The switch tubes S6 and S5 are complementary turned on, and the switch tubes S7 and S8 are complementary turned on;

[0163] The switch S9 is turned on with a duty cycle of 50% and a frequency of fs, and its on-time is ahead of (or behind) the switch S8 by a fourth time Dt4; the switch S10 and the switch S9 are turned on complementary to each other;

[0164] The LVDC port switch tubes S11 and S12 perform synchronous rectification timing work, the switch tube S13 and the switch tube S11 are complementary turned on, and the switch tube S14 and the switch tube S12 are complementary turned on.

[0165] In forward three-port simultaneous operation, see Figure 4 , which is a second timing control diagram corresponding to the switch of a charging control circuit provided by the present application when the three forward ports work simultaneously. When the AC port voltage is less than 0, the AC port switches S1b, S2b, S3b, and S4b are continuously turned on;

[0166] Switch S2a is turned on with a duty cycle of 50% and a frequency of fs;

[0167] The switch S3a is turned on with a duty cycle of 50% and a frequency of fs, and is turned on after the switch S2a by a fifth time Dt5.

[0168] The switch tubes S1a and S2a are complementary turned on, and the switch tubes S4a and S3a are complementary turned on;

[0169] The HVDC port switch S5 is turned on with a duty cycle of 50% and a frequency of fs, and is turned on after the switch S2a by a sixth time Dt6.

[0170] The switch tube S8 is turned on with a duty cycle of 50% and a frequency of fs, and its turn-on time lags behind the turn-on time of the switch tube S5 by seven time periods Dt7;

[0171] The switch tube S6 and the switch tube S5 are complementary turned on, and the switch tube S7 and the switch tube S8 are complementary turned on;

[0172] The switch S9 is turned on with a duty cycle of 50% and a frequency of fs, and its on-time is ahead of (or behind) the switch S8 by the eighth time Dt8; the switch S10 and the switch S9 are turned on in a complementary manner;

[0173] The LVDC port switch tubes S11 and S12 perform synchronous rectification timing work, the switch tube S13 and the switch tube S11 are complementary turned on, and the switch tube S14 and the switch tube S12 are complementary turned on.

[0174] In reverse three-port simultaneous operation, see Figure 5 , is a first timing control diagram corresponding to the switch of a charging control circuit provided by this application when the three ports work simultaneously in reverse, and power is transmitted from the HVDC port to the AC and LVDC ports simultaneously, as detailed below:

[0175] With reference to the simultaneous operation of the three forward ports, to achieve reverse power transmission, the voltage between the midpoints of the third and fourth arms of the HVDC port must be controlled to lead the voltage between the midpoints of the first and second arms of the AC port.

[0176] When the voltage of the AC port is greater than 0, the AC port switches S1a, S2a, S3a, and S4a are continuously turned on;

[0177] The HVDC port switch S5 is turned on with a duty cycle of 50% and a frequency of fs;

[0178] The switch tube S8 is turned on with a duty cycle of 50%, a frequency of fs, and is turned on after the switch tube S5 is turned on for a first time Dt1;

[0179] The switch tube S6 and the switch tube S5 are complementary turned on, and the switch tube S7 and the switch tube S8 are complementary turned on;

[0180] The switch S1b is turned on with a duty cycle of 50% and a frequency of fs, and is turned on after the switch S5 by a second time Dt2.

[0181] The switch S4b is turned on with a duty cycle of 50% and a frequency of fs, and is turned on after the switch S1b is turned on for a third time Dt3;

[0182] The switch tubes S2b and S1b are complementary turned on, and the switch tubes S3b and S4b are complementary turned on;

[0183] The switch S9 is turned on with a duty cycle of 50% and a frequency of fs, and its on-time is ahead (or behind) that of the switch S8 by a fourth time; the switch S10 and the switch S9 are turned on in a complementary manner;

[0184] The LVDC port switch tubes S11 and S12 perform synchronous rectification timing work, the switch tube S13 and the switch tube S11 are complementary turned on, and the switch tube S14 and the switch tube S12 are complementary turned on.

[0185] In reverse three-port simultaneous operation, see Figure 6 , which is a second timing control diagram corresponding to the switch of a charging control circuit provided by this application when the three ports in reverse direction work simultaneously, and power is transmitted from the HVDC port to the AC and LVDC ports simultaneously, as detailed below:

[0186] When the voltage of the AC port is less than 0, the AC port switches S1b, S2b, S3b, and S4b are continuously turned on;

[0187] The HVDC port switch S5 is turned on with a duty cycle of 50% and a frequency of fs;

[0188] The switch S8 is turned on with a duty cycle of 50% and a frequency of fs, and its turn-on time lags behind the turn-on time of the switch S5 by a fifth time Dt5;

[0189] The switch tubes S6 and S5 are complementary turned on, and the switch tubes S7 and S8 are complementary turned on;

[0190] The switch S2a is turned on with a duty cycle of 50% and a frequency of fs, and is turned on after the switch S5 by a sixth time Dt6.

[0191] The switch S3a is turned on with a duty cycle of 50% and a frequency of fs, and is turned on after the switch S2a by a seventh time Dt7.

[0192] The switch tubes S2a and S1a are complementary turned on, and the switch tubes S3a and S4a are complementary turned on;

[0193] The switch S9 is turned on with a duty cycle of 50% and a frequency of fs, and its on-time is ahead of (or behind) the switch S8 by the eighth time Dt8; the switch S10 and the switch S9 are turned on in a complementary manner;

[0194] The LVDC port switch tubes S11 and S12 perform synchronous rectification timing work, the switch tube S13 and the switch tube S11 are complementary turned on, and the switch tube S14 and the switch tube S12 are complementary turned on.

[0195] If in single low-voltage DCDC step-down operation, switches S1a, S1b, S2a, S2b, S3a, S3b, S4a, and S4b remain off; switches S7, S8, S9, and S10 perform phase-shifted full-bridge control or variable duty cycle control, switch S5 maintains a switching signal synchronized with switch S7, and switch S6 maintains a switching signal synchronized with switch S8, so that the voltage between the midpoints of the third and fourth bridge arms is ideally controlled to be 0, minimizing device losses.

[0196] In this embodiment, the charging control circuit and the on-board charger described above bring the following technical effects:

[0197] First, the on-board charger of this application fully integrates the PFC inductor, busbar capacitor and high-voltage power switch tube, which can further optimize the layout and improve the power density of the product;

[0198] Second, the on-board charger of the present application achieves bidirectional conversion through a matrix rectifier bridge and a resonant network. The matrix rectifier bridge solves the problem of large conduction voltage drop and severe heat generation in traditional bridge arms, which rely on body diode conduction under reverse voltage. The bidirectional power flow eliminates the need for additional switches or relays, reducing circuit complexity and, in particular, losses at high switching frequencies. Furthermore, the inclusion of a resonant circuit enables a higher voltage gain and enables power conversion over a wider range. When the LVDC operates alone, there is no need to control the AC port, and no additional power device losses are added, which further improves the efficiency of the LVDC circuit.

[0199] Third, the on-board charger of the present application optimizes costs by using a shared bridge arm design in the first and second transformers. For example, by sharing a portion of the bridge arm of the first secondary conversion circuit and the first primary conversion circuit, losses during energy conversion are reduced, thereby improving overall conversion efficiency. Furthermore, overlapping circuits and redundant components are reduced, optimizing the volume, weight, and production cost of the integrated product, thereby improving integration and compactness.

[0200] Fourth, the on-board charger of the present application switches between AC, high-voltage DC and low-voltage DC according to different application scenarios and needs, greatly improving the flexibility of the charging control scheme and the practicality of various usage scenarios.

[0201] The above embodiments are merely illustrative of the principles and effects of this application and are not intended to limit this application. Anyone skilled in the art may modify or alter the above embodiments without departing from the spirit and scope of this application. Therefore, all equivalent modifications or alterations made by one of ordinary skill in the art without departing from the spirit and technical concepts disclosed in this application shall be covered by the claims of this application.

Claims

1. A charging control circuit, characterized in that: include: a first primary-side conversion circuit and a first secondary-side conversion circuit connected to a first transformer, wherein the first primary-side conversion circuit includes a matrix rectifier bridge and a resonant network, wherein a first AC side of the matrix rectifier bridge is a first port, and a second AC side of the matrix rectifier bridge is connected to the first transformer via the resonant network; A second primary conversion circuit and a second secondary conversion circuit are connected to the second transformer; wherein the first transformer and the second transformer are independent of each other, the DC side of the first secondary conversion circuit is a high-voltage second port, and the DC side of the second secondary conversion circuit is a low-voltage third port.

2. The charging control circuit according to claim 1, wherein: The matrix rectifier bridge includes a first bridge arm and a second bridge arm, the first bridge arm and the second bridge arm form a full bridge structure, and the upper bridge arm and the lower bridge arm of each bridge arm are composed of at least one group of switches with opposite polarities.

3. The charging control circuit according to claim 2, wherein: The upper bridge arm of the first bridge arm is composed of a first switching tube and a second switching tube with opposite polarities, and the lower bridge arm of the first bridge arm is composed of a third switching tube and a fourth switching tube with opposite polarities; the upper bridge arm of the second bridge arm is composed of a fifth switching tube and a sixth switching tube with opposite polarities, and the lower bridge arm of the second bridge arm is composed of a seventh switching tube and an eighth switching tube with opposite polarities.

4. The charging control circuit according to claim 1, wherein: The matrix rectifier bridge includes a first bridge arm and a second bridge arm, the first bridge arm and the second bridge arm constitute a full-bridge structure, the upper bridge arm of the first bridge arm is a first bidirectional GaN device, and the lower bridge arm of the first bridge arm is a second bidirectional GaN device; the upper bridge arm of the second bridge arm is a third bidirectional GaN device, and the lower bridge arm of the second bridge arm is a fourth bidirectional GaN device.

5. The charging control circuit according to claim 1, wherein: The matrix rectifier bridge includes a first bridge arm and a second bridge arm, the first bridge arm and the second bridge arm constitute a full-bridge structure, the upper bridge arm of the first bridge arm is a first bidirectional GaN device, and the lower bridge arm of the first bridge arm is a second bidirectional GaN device; the upper bridge arm of the second bridge arm is composed of a fifth switching tube and a sixth switching tube with opposite polarities, and the lower bridge arm of the second bridge arm is composed of a seventh switching tube and an eighth switching tube with opposite polarities.

6. The charging control circuit according to claim 1, wherein: The matrix rectifier bridge includes a first bridge arm and a second bridge arm, the first bridge arm and the second bridge arm constitute a full-bridge structure, the upper and lower bridge arms of the first bridge arm and the second bridge arm are composed of bidirectional GaN devices and back-to-back switches, and the back-to-back switches are composed of two switches with opposite polarities.

7. The charging control circuit according to claim 3, 5 or 6, characterized in that: A back-to-back common drain structure is formed between the two switches with opposite polarities.

8. The charging control circuit according to any one of claims 3 to 5, characterized in that: Also includes: The driving signal of the first switch tube and the upper driving signal of the first bidirectional GaN device are driving signals 1a, and the driving signal of the second switch tube and the lower driving signal of the first bidirectional GaN device are driving signals 1b; The driving signal of the third switching tube and the upper driving signal of the second bidirectional GaN device are driving signal 2a, and the driving signal of the fourth switching tube and the lower driving signal of the second bidirectional GaN device are driving signal 2b. The driving signal of the fifth switching tube and the upper driving signal of the third bidirectional GaN device are driving signal 3a, and the driving signal of the sixth switching tube and the lower driving signal of the third bidirectional GaN device are driving signal 3b. The driving signal of the seventh switch tube and the up driving signal of the fourth bidirectional GaN device are the 4a driving signal, and the driving signal of the eighth switch tube and the down driving signal of the fourth bidirectional GaN device are the 4b driving signal.

9. The charging control circuit according to claim 1, wherein: Also includes: When power is transmitted from the first port to the second port, or when power is transmitted from the second port to the first port, the second transformer is short-circuited by controlling the conduction state in the second secondary conversion circuit to prevent energy from being transmitted to the third port through the second transformer; or, when power is transmitted from the second port to the third port, or when power is transmitted from the third port to the second port, the first transformer is short-circuited by controlling the conduction state in the first secondary conversion circuit to prevent energy from being transmitted to the first port through the first transformer.

10. The charging control circuit according to claim 1, wherein: The resonant network includes a first resonant inductor, a first resonant capacitor and an excitation inductor. The midpoint of the first bridge arm is connected to the same-name end of the first winding in the first transformer through the first resonant inductor, the midpoint of the second bridge arm is connected to the opposite-name end of the first winding through the first resonant capacitor, and the excitation inductor is connected in parallel at both ends of the first winding.

11. The charging control circuit according to claim 8, wherein: The first secondary side conversion circuit includes a third bridge arm and a fourth bridge arm, and the first transformer includes a second winding as a secondary coil, wherein the second winding is connected between the midpoint of the third bridge arm and the midpoint of the fourth bridge arm; the second primary side conversion circuit includes a fifth bridge arm and a shared fourth bridge arm, and the second transformer includes a third winding as a main coil, wherein the third winding is connected between the midpoint of the fourth bridge arm and the midpoint of the fifth bridge arm, and the two ends of the third bridge arm, the fourth bridge arm and the fifth bridge arm serve as second ports for connecting high-voltage direct current.

12. The charging control circuit according to claim 11, wherein: The upper and lower bridge arms of the third bridge arm are the ninth switching tube and the tenth switching tube respectively; the upper and lower bridge arms of the fourth bridge arm are the eleventh switching tube and the twelfth switching tube respectively; the upper and lower bridge arms of the fifth bridge arm are the thirteenth switching tube and the fourteenth switching tube respectively, wherein the driving signals corresponding to the ninth switching tube, the tenth switching tube, the eleventh switching tube, the twelfth switching tube, the thirteenth switching tube and the fourteenth switching tube are the fifth driving signal, the sixth driving signal, the seventh driving signal, the eighth driving signal, the ninth driving signal and the tenth driving signal respectively.

13. The charging control circuit according to claim 12, wherein: The control method of the charging control circuit includes: During forward three-port operation, if the voltage of the first port is greater than zero, the 1a drive signal, the 2a drive signal, the 3a drive signal, and the 4a drive signal are continuously on signals, and the 1b drive signal and the 4b drive signal control the corresponding switch tubes to turn on and off at a preset duty cycle and a preset frequency, wherein the 4b drive signal lags behind the 1b drive signal by a first preset time, the 1b drive signal and the 2b drive signal are complementary, and the 3b drive signal and the 4b drive signal are complementary; At the second port, based on the phase-shift control strategy, the fifth drive signal and the eighth drive signal control the corresponding switch tube to be turned on and off with a preset duty cycle and a preset frequency, and the fifth drive signal lags behind the 1b drive signal by a second preset time, and the eighth drive signal lags behind the fifth drive signal by a third preset time. By controlling the first secondary-side conversion circuit, the AC voltage is rectified into a DC voltage, and power is transmitted to the second port; wherein, the fifth drive signal and the sixth drive signal, as well as the seventh drive signal and the eighth drive signal, are complementary; at the same time, based on the phase-shift control strategy, the ninth drive signal controls the corresponding switch tube to be turned on and off with a preset duty cycle and a preset frequency, and the ninth drive signal leads or lags behind the eighth drive signal by a fourth preset time, wherein the ninth drive signal and the tenth drive signal are complementary.

14. The charging control circuit according to claim 13, wherein: The control method of the charging control circuit also includes: During forward three-port operation, if the voltage of the first port is less than zero, the 1b drive signal, the 2b drive signal, the 3b drive signal, and the 4b drive signal are continuously on signals, and the 2a drive signal and the 3a drive signal control the corresponding switch tubes to turn on and off at a preset duty cycle and a preset frequency, wherein the 3a drive signal lags behind the 2a drive signal by a fifth preset time, the 1a drive signal and the 2a drive signal are complementary, and the 3a drive signal and the 4a drive signal are complementary; At the second port, based on the phase-shift control strategy, the fifth drive signal and the eighth drive signal control the corresponding switch tube to be turned on and off with a preset duty cycle and a preset frequency, and the fifth drive signal lags behind the 2a drive signal by a sixth preset time, and the eighth drive signal lags behind the fifth drive signal by a seventh preset time. By controlling the first secondary-side conversion circuit, the AC voltage is rectified into a DC voltage, and power is transmitted to the second port; wherein, the fifth drive signal and the sixth drive signal, as well as the seventh drive signal and the eighth drive signal, are complementary; at the same time, based on the phase-shift control strategy, the ninth drive signal controls the corresponding switch tube to be turned on and off with a preset duty cycle and a preset frequency, and the ninth drive signal leads or lags behind the eighth drive signal by an eighth preset time, wherein the ninth drive signal and the tenth drive signal are complementary.

15. The charging control circuit according to claim 13, wherein: The control method of the charging control circuit also includes: During forward three-port operation, if the voltage of the first port is less than zero, the 1b drive signal, the 2b drive signal, the 3b drive signal, and the 4b drive signal are continuously on signals, and the 2a drive signal and the 3a drive signal control the corresponding switch tubes to turn on and off at a preset duty cycle and a preset frequency, wherein the 2a drive signal lags behind the 3a drive signal by a fifth preset time, the 1a drive signal and the 2a drive signal are complementary, and the 3a drive signal and the 4a drive signal are complementary; At the second port, based on the phase-shift control strategy, the fifth drive signal and the eighth drive signal control the corresponding switch tube to be turned on and off with a preset duty cycle and a preset frequency, and the fifth drive signal lags behind the 3a drive signal by a sixth preset time, and the eighth drive signal lags behind the fifth drive signal by a seventh preset time. By controlling the first secondary-side conversion circuit, the AC voltage is rectified into a DC voltage, and power is transmitted to the second port; wherein, the fifth drive signal and the sixth drive signal, as well as the seventh drive signal and the eighth drive signal, are complementary; at the same time, based on the phase-shift control strategy, the ninth drive signal controls the corresponding switch tube to be turned on and off with a preset duty cycle and a preset frequency, and the ninth drive signal leads or lags behind the eighth drive signal by an eighth preset time, wherein the ninth drive signal and the tenth drive signal are complementary.

16. The charging control circuit according to claim 12, wherein: The control method of the charging control circuit also includes: During reverse three-port operation, if the voltage of the first port is greater than zero, the 1a drive signal, the 2a drive signal, the 3a drive signal, and the 4a drive signal are continuously on signals; based on a phase-shift control strategy, the 5th drive signal and the 8th drive signal control the corresponding switch tubes to turn on and off at a preset duty cycle and a preset frequency, and the 8th drive signal lags behind the 5th drive signal by a first preset time, thereby inverting the DC voltage into an AC voltage, wherein the 5th drive signal and the 6th drive signal, as well as the 7th drive signal and the 8th drive signal, are complementary; The 1b drive signal and the 4b drive signal control the corresponding switch tubes to turn on and off at a preset duty cycle and a preset frequency, and the 1b drive signal lags behind the 5th drive signal by a second preset time, and the 4b drive signal lags behind the 1b drive signal by a third preset time, so that the AC voltage transmits power to the first port, wherein the 1b drive signal and the 2b drive signal are complementary, and the 3b drive signal and the 4b drive signal are complementary.

17. The charging control circuit according to claim 16, wherein: The control method of the charging control circuit also includes: During reverse three-port operation, if the voltage of the first port is less than zero, the 1b drive signal, the 2b drive signal, the 3b drive signal, and the 4b drive signal are continuously on signals, and based on the phase-shift control strategy, the 5th drive signal and the 8th drive signal control the corresponding switch tubes to turn on and off at a preset duty cycle and a preset frequency, and the 8th drive signal lags behind the 5th drive signal by a fifth preset time; the DC voltage is inverted into an AC voltage, wherein the 5th drive signal and the 6th drive signal, as well as the 7th drive signal and the 8th drive signal, are complementary; The 2a drive signal and the 3a drive signal control the corresponding switch tube to be turned on and off at a preset duty cycle and a preset frequency, and the 2a drive signal lags behind the 5th drive signal by a sixth preset time, and the 3a drive signal lags behind the 2a drive signal by a seventh preset time, so that the AC voltage transmits power to the first port, wherein the 1a drive signal and the 2a drive signal are complementary to each other, and the 3a drive signal and the 4a drive signal are complementary to each other.

18. The charging control circuit according to claim 16, wherein: The control method of the charging control circuit also includes: During reverse three-port operation, if the voltage of the first port is less than zero, the 1b drive signal, the 2b drive signal, the 3b drive signal, and the 4b drive signal are continuously on signals, and based on the phase-shift control strategy, the 5th drive signal and the 8th drive signal control the corresponding switch tubes to turn on and off at a preset duty cycle and a preset frequency, and the 8th drive signal lags behind the 5th drive signal by a fifth preset time; the DC voltage is inverted into an AC voltage, wherein the 5th drive signal and the 6th drive signal, as well as the 7th drive signal and the 8th drive signal, are complementary; The 2a drive signal and the 3a drive signal control the corresponding switch tube to turn on and off at a preset duty cycle and a preset frequency, and the 3a drive signal lags behind the 5th drive signal by a sixth preset time, and the 2a drive signal lags behind the 3a drive signal by a seventh preset time, so that the AC voltage transmits power to the first port, wherein the 1a drive signal and the 2a drive signal are complementary to each other, and the 3a drive signal and the 4a drive signal are complementary to each other.

19. The charging control circuit according to claim 12, wherein: The control method of the charging control circuit also includes: When operating in a single low-voltage DCDC mode, the 1a, 1b, 2a, 2b, 3a, 3b, 4a, and 4b drive signals are off signals, and phase-shifted full-bridge control or variable duty cycle control is performed on the three bridge arms and the fourth bridge arm. The fifth drive signal and the seventh drive signal control the corresponding switching tubes to be synchronously turned on and off, and the sixth drive signal and the eighth drive signal control the corresponding switching tubes to be synchronously turned on and off, so that the voltage between the third bridge arm and the fourth bridge arm approaches zero. In which, when the low-voltage DCDC is working alone in step-down mode, the voltage duty cycle of the midpoint of the fourth bridge arm and the fifth bridge arm or the operating duty cycle of the switch tube in the fourth bridge arm and the fifth bridge arm is adjusted, and the high-voltage DC voltage is converted into a low-voltage DC voltage through synchronous rectification, and power is transmitted to the third port; or, when the low-voltage DCDC is working alone in step-up mode, whether the second primary side conversion circuit performs synchronous rectification is controlled to convert the low-voltage DC voltage into a high-voltage DC voltage, and power is transmitted to the second port.

20. A vehicle-mounted charger, characterized in that: Use the charging control circuit described in any one of claims 1 to 19.

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