Energy conversion device and vehicle

Abstract

The embodiment of the present application provides an energy conversion device and a vehicle, the energy conversion device comprises a rectifying module, at least one direct current / direct current (DC / DC) module and a control module, a first end of the rectifying module is connected with a first alternating current end, a second end of the rectifying module is connected with a second alternating current end, a third end of the rectifying module is connected with a first end of the first DC / DC module, a fourth end of the rectifying module is connected with a second end of the first DC / DC module, a third end of the first DC / DC module is connected with a first direct current end, and a fourth end of the first DC / DC module is connected with a second direct current end; in the case that the energy conversion device works in a reverse discharge mode, the control module determines a duty cycle of a switch tube in the first DC / DC module according to a first sampling voltage or a second sampling voltage, and controls conduction or turn-off of a rectifying tube in the rectifying module, so as to realize a direct current / alternating current function of the energy conversion device. The embodiment of the present application can reduce the volume and cost of the energy conversion device.

Description

TECHNICAL FIELD

[0001] The present application relates to the technical field of electronic circuits, and in particular to an energy conversion device and a vehicle. BACKGROUND

[0002] With the development of electric vehicles, the on-board charger as an energy conversion device of the electric vehicle has attracted more and more attention. The energy conversion device can convert alternating current into direct current to charge the high-voltage battery in the electric vehicle. The energy conversion device usually adopts a two-stage architecture of a power factor correction (PFC) module and a direct current / direct current (DC / DC) module, which leads to an increase in the size and cost of the energy conversion device and a low power density. SUMMARY

[0003] The embodiments of the present application provide an energy conversion device and a vehicle, which can reduce the size and cost of the energy conversion device.

[0004] The first aspect of the embodiments of the present application provides an energy conversion device, comprising a rectifier module, at least one direct current / direct current (DC / DC) module, and a control module. A first end of the rectifier module is connected to a first alternating current end, a second end of the rectifier module is connected to a second alternating current end, a third end of the rectifier module is connected to a first end of a first DC / DC module, a fourth end of the rectifier module is connected to a second end of the first DC / DC module, a third end of the first DC / DC module is connected to a first direct current end, and a fourth end of the first DC / DC module is connected to a second direct current end. The first DC / DC module is any one of the at least one DC / DC module.

[0005] In a case where the energy conversion device works in a reverse discharge mode, the control module determines a duty cycle of a switch tube in the first DC / DC module according to a first sampling voltage or a second sampling voltage, controls conduction or turn-off of a rectifier tube in the rectifier module, to realize a direct current / alternating current function of the energy conversion device. The first sampling voltage is a sampling voltage between the first end of the rectifier module and the second end of the rectifier module, and the second sampling voltage is a sampling voltage between the first end of the first DC / DC module and the second end of the first DC / DC module.

[0006] The energy conversion device of the embodiment of the present application adopts a single-stage topology. Compared with a two-stage architecture adopting a PFC module and a DC / DC module, the number of active devices can be reduced, thereby reducing the cost and volume of the energy conversion device. The control module can determine the duty cycle of the switching tube in the first DC / DC module according to the first sampling voltage or the second sampling voltage, and control the conduction or turn-off of the rectifier tube in the rectifier module to realize the direct current to alternating current function of the energy conversion device, so that the energy conversion device works in the reverse discharge mode, thereby expanding the application scenarios of the energy conversion device.

[0007] The at least one DC / DC module is connected in an interleaved and parallel manner, thereby improving the output power of the energy conversion device and being applicable to high-power scenarios.

[0008] Optionally, the first DC / DC module comprises a first capacitor, a second capacitor, a third capacitor, a first switching tube, a second switching tube, a first inductor, a second inductor and a transformer; a first end of the first capacitor is connected to a first end of the first inductor and a third end of the rectifier module, a second end of the first inductor is connected to a first end of the second capacitor and a first end of the first switching tube, a second end of the second capacitor is connected to a first end of a primary winding of the transformer, a second end of the first capacitor is connected to a second end of the first switching tube, a second end of the second inductor, a second end of the primary winding and a fourth end of the rectifier module; a first end of a secondary winding of the transformer is connected to a first end of the second switching tube, a second end of the second switching tube is connected to a first end of the third capacitor and the first direct current end, and a second end of the secondary winding is connected to a second end of the third capacitor and the second direct current end.

[0009] In the embodiment of the present application, the first DC / DC module comprises two switching tubes: a first switching tube and a second switching tube. A traditional single-stage alternating current / direct current (AC / DC) module comprises at least two bridge arms (at least four switching tubes). Compared with the traditional single-stage AC / DC module, the first DC / DC module of the present application can reduce the number of switching tubes, thereby further reducing the cost and volume of the energy conversion device.

[0010] The transformer can be an isolation transformer, which can realize the isolation between the alternating current end (the first alternating current end and the second alternating current end) and the direct current end (the first direct current end and the second direct current end).

[0011] Optionally, the second inductor is an excitation inductance in the primary winding of the transformer.

[0012] In the embodiments of the present application, the second inductor can reuse the excitation inductance in the primary winding of the transformer, thereby improving the integration of the first DC / DC module, reducing the cost and volume of the first DC / DC module, and further reducing the cost and volume of the energy conversion device.

[0013] Optionally, the rectifier module includes a first rectifier tube, a second rectifier tube, a third rectifier tube, and a fourth rectifier tube, a first end of the first rectifier tube is connected to a first end of the second rectifier tube and a first end of the first DC / DC module, a second end of the first rectifier tube is connected to a first end of the third rectifier tube and the first AC end, a second end of the second rectifier tube is connected to a first end of the fourth rectifier tube and the second AC end, and a second end of the third rectifier tube is connected to a second end of the fourth rectifier tube and a second end of the first DC / DC module.

[0014] In the embodiments of the present application, the rectifier module includes four rectifier tubes, and the control module can control the conduction or turn-off of the rectifier tubes in the rectifier module. The rectifier tube is different from a simple diode, so that the rectifier module can support bidirectional rectification, thereby allowing the energy conversion device to work in a forward charging mode (the energy conversion device can convert the AC power at the first AC end and the second AC end into DC power, and the DC power is output from the first DC end and the second DC end to the positive and negative electrodes of the battery, thereby realizing charging of the battery) and a reverse discharging mode (the energy conversion device can convert the DC power at the first DC end and the second DC end into AC power, and the AC end is output from the first AC end and the second AC end to an AC load (a load supporting AC power supply), thereby realizing power supply for the AC load), thereby expanding the application scenarios of the energy conversion device.

[0015] Optionally, each rectifier tube includes an insulated gate bipolar transistor (IGBT) or a metal oxide semiconductor field effect transistor (MOSFET).

[0016] In the embodiments of the present application, the MOSFET can also be referred to as a MOS tube. The rectifier tube can be an IGBT or a MOS tube, and the use of an IGBT for the rectifier tube can reduce the cost, and the use of a MOS tube for the rectifier tube can reduce the conduction loss.

[0017] Optionally, the control module determines the duty cycle of the switch tube in the first DC / DC module according to the first sampling voltage or the second sampling voltage, controls the conduction or turn-off of the rectifier tube in the rectifier module, and realizes the DC-to-AC function of the energy conversion device, including:

[0018] The control module determines the duty cycle of the switch tube in the first DC / DC module according to the first sampling voltage or the second sampling voltage and a first sampling current, and controls the turn-on or turn-off of the rectifier tube in the rectifier module to realize the direct current to alternating current function of the energy conversion device, and the first sampling current is the current on the first inductor.

[0019] In the embodiment, the first sampling voltage is the sampling voltage output by the energy conversion device when working in the reverse discharge mode, and the control module can adjust the voltage output by the energy conversion device according to the sampling voltage output by the energy conversion device when working in the reverse discharge mode, so as to ensure the stability of the voltage output by the energy conversion device. The first sampling current is the sampling current on the first inductor, and the current on the first inductor will change with the change of the load of the output end (the first alternating current end and the second alternating current end) of the energy conversion device. The control module can adjust the current on the first inductor according to the sampling current on the first inductor, so that the dynamic characteristics of the load of the output end of the energy conversion device are improved and the current limiting effect is achieved. When the energy conversion device works in the reverse discharge mode, the sampling current on the first inductor is the sampling current output by the energy conversion device. The control module determines the duty cycle of the switch tube in the first DC / DC module according to the first sampling voltage or the second sampling voltage and the first sampling current, so as to ensure the stability of the voltage and current output by the energy conversion device when the energy conversion device works in the reverse discharge mode.

[0020] Optionally, the control module determines the duty cycle of the switch tube in the first DC / DC module according to the first sampling voltage or the second sampling voltage and the first sampling current, and controls the turn-on or turn-off of the rectifier tube in the rectifier module to realize the direct current to alternating current function of the energy conversion device, including:

[0021] The control module determines the first reference current according to the first sampling voltage or the second sampling voltage and a first reference voltage, and determines the duty cycle of the second switch tube according to the first sampling current and the first reference current.

[0022] When the required alternating current voltage between the first alternating current end and the second alternating current end is a positive half wave, the control module controls the first rectifier tube and the fourth rectifier tube to be turned on, and the second rectifier tube and the third rectifier tube to be turned off.

[0023] When the required alternating current voltage between the first alternating current end and the second alternating current end is a negative half wave, the control module controls the second rectifier tube and the third rectifier tube to be turned on, and the first rectifier tube and the fourth rectifier tube to be turned off.

[0024] Optionally, the control module comprises: a first voltage control loop and a first current control loop, in a case that the control module determines the first reference current according to the first sampling voltage and the first reference voltage, and determines the duty cycle of the second switch according to the first sampling current and the first reference current;

[0025] The first voltage control loop is configured to perform loop calculation on a result of subtraction between the first reference voltage and the first sampling voltage, and output a first loop current, wherein the first reference current is an absolute value of the first loop current.

[0026] The first current control loop is configured to perform loop calculation on a result of subtraction between the first reference current and the first sampling current, and output the duty cycle of the second switch.

[0027] Optionally, in a case that the control module determines the first reference current according to the second sampling voltage and the first reference voltage, and determines the duty cycle of the second switch according to the first sampling current and the first reference current, the control module comprises: a second voltage control loop and a second current control loop;

[0028] The second voltage control loop is configured to perform loop calculation on a result of subtraction between an absolute value of the first reference voltage and the second sampling voltage, and output the first reference current.

[0029] The second current control loop is configured to perform loop calculation on a result of subtraction between the first reference current and the first sampling current, and output the duty cycle of the second switch.

[0030] Optionally, in a case that the control module determines the duty cycle of the switch in the first DC / DC module according to the first sampling voltage, the control module comprises: a third voltage control loop;

[0031] The third voltage control loop is configured to perform loop calculation on a result of subtraction between the first reference voltage and the first sampling voltage, and output the duty cycle of the second switch.

[0032] In the embodiments of the present application, in a case that the control module determines the duty cycle of the switch in the first DC / DC module according to the first sampling voltage, the duty cycle of the second switch can be determined by one voltage control loop, without using a current control loop, thereby reducing the complexity of the control module.

[0033] Optionally, in a case that the control module determines the duty cycle of the switch in the first DC / DC module according to the second sampling voltage, the control module comprises: a fourth voltage control loop;

[0034] The fourth voltage control loop is configured to perform loop calculation on a result of subtraction between an absolute value of the first reference voltage and the second sampling voltage, and output a duty cycle of the second switch tube.

[0035] In the embodiment of the present application, in the case that the control module determines the duty cycle of the switch tube in the first DC / DC module according to the second sampling voltage, the duty cycle of the second switch tube can be determined by one voltage control loop, without using a current control loop, thereby reducing the complexity of the control module.

[0036] The second aspect of the embodiment of the present application provides a vehicle comprising the energy conversion device and the battery of the first aspect of the embodiment of the present application, and the energy conversion device is configured to convert direct current of the battery into alternating current to realize the reverse discharge function.

[0037] The energy conversion device of the embodiment of the present application adopts a single-stage topology, and compared with a two-stage architecture adopting a PFC module and a DC / DC module, the number of active devices can be reduced, thereby reducing the cost and volume of the energy conversion device. The control module can determine the duty cycle of the switch tube in the first DC / DC module according to the first sampling voltage or the second sampling voltage, and control the conduction or turn-off of the rectifier tube in the rectifier module to realize the direct current to alternating current function of the energy conversion device, so that the energy conversion device works in the reverse discharge mode, and the application scenarios of the energy conversion device are expanded. BRIEF DESCRIPTION OF DRAWINGS

[0038] In order to more clearly illustrate the technical solutions of the embodiments of the present application or the prior art, the drawings needed in the embodiment or prior art description will be briefly introduced below. Obviously, the drawings in the following description are only some embodiments of the present application, and other drawings can be obtained by those skilled in the art without creative labor.

[0039] Figure 1 is a structural schematic diagram of an energy conversion device provided by the embodiment of the present application;

[0040] Figure 2 is a structural schematic diagram of a control module in a reverse discharge mode provided by the embodiment of the present application;

[0041] Figure 3 is a structural schematic diagram of another control module in a reverse discharge mode provided by the embodiment of the present application;

[0042] Figure 4 is a structural schematic diagram of still another control module in a reverse discharge mode provided by the embodiment of the present application;

[0043] Figure 5This is a structural diagram of a control module in another reverse discharge mode provided by an embodiment of the present application;

[0044] Figure 6 1 is a schematic diagram of the waveform of the AC voltage output from the first AC terminal and the second AC terminal of an energy conversion device provided in an embodiment of the present application;

[0045] Figure 7 It is a structural schematic diagram of a vehicle provided in an embodiment of the present application. DETAILED DESCRIPTION

[0046] The following will be combined with the drawings in the embodiments of this application to clearly and completely describe the technical solutions in the embodiments of this application. Obviously, the embodiments described are only part of the embodiments of this application, not all of the embodiments. Based on the embodiments in this application, all other embodiments obtained by those skilled in the art without making creative efforts are within the scope of protection of this application.

[0047] The terms "first," "second," and the like in the specification and claims of this application and the accompanying drawings are used to distinguish between different objects, not to describe a particular order. Furthermore, the terms "including," "having," and any variations thereof, are intended to cover non-exclusive inclusions. For example, a process, system, product, or apparatus comprising a series of steps or elements is not limited to the listed steps or elements, but may optionally include steps or elements not listed, or may optionally include other steps or elements inherent to the process, product, or apparatus.

[0048] References to "embodiments" in this application mean that a particular feature, structure, or characteristic described in connection with the embodiment may be included in at least one embodiment of the application. The appearance of this phrase in various places in the specification does not necessarily refer to the same embodiment, nor does it constitute an independent or alternative embodiment that is mutually exclusive of other embodiments. It is understood, both explicitly and implicitly, by those skilled in the art that the embodiments described in this application may be combined with other embodiments.

[0049] See also Figure 1 , Figure 1 This is a schematic diagram of the structure of an energy conversion device provided in an embodiment of the present application. Figure 1 As shown, the energy conversion device may include a rectifier module 10, at least one DC / DC module and a control module 30. The at least one DC / DC module may include one or more DC / DC modules. Figure 1 It is taken as an example that at least one DC / DC module includes a DC / DC module.

[0050] The first end of the rectifier module 10 is connected to the first AC end (such as Figure 1AC_L shown in FIG), the second end of the rectifier module 10 is connected to the second AC end (such as Figure 1 AC_N shown in the figure), the third end of the rectifier module 10 is connected to the first end of the first DC / DC module 21, the fourth end of the rectifier module 10 is connected to the second end of the first DC / DC module 21, the third end of the first DC / DC module 21 is connected to the first DC end, and the fourth end of the first DC / DC module 21 is connected to the second DC end; the first DC / DC module 21 is any one of the at least one DC-to-DC converter DC / DC module;

[0051] When the energy conversion device operates in the reverse discharge mode, the control module 30 generates a voltage signal according to the first sampling voltage (e.g. Figure 1 The V ac ) or the second sampling voltage (such as Figure 1 The V rec ) determines the duty cycle of the switching tube in the first DC / DC module 21, controls the on or off of the rectifier tube in the rectifier module 10, so as to realize the DC-to-AC function of the energy conversion device; the first sampling voltage is the sampling voltage between the first end of the rectifier module 10 and the second end of the rectifier module 10, and the second sampling voltage is the sampling voltage between the first end of the first DC / DC module 21 and the second end of the first DC / DC module 21.

[0052] In one possible embodiment, the energy conversion device can implement an alternating current / direct current (AC / DC) conversion function. In this case, the first AC terminal and the second AC terminal serve as AC input terminals, and the first DC terminal and the second DC terminal serve as DC output terminals. The energy conversion device can convert the input AC into a DC output.

[0053] In one possible embodiment, the energy conversion device can convert direct current (DC) into alternating current (AC). In this case, the first AC terminal and the second AC terminal serve as AC output terminals, and the first DC terminal and the second DC terminal serve as DC input terminals. The energy conversion device can convert the input DC into AC output.

[0054] For example, the energy conversion device may be an onboard charger on a vehicle, which may be a bidirectional onboard charger capable of converting AC to DC and DC to AC.

[0055] In the embodiment of the present application, the energy conversion device can operate in a reverse discharge mode and a forward charging mode, which can expand the application scenarios of the energy conversion device.

[0056] When the energy conversion device operates in the reverse discharge mode, the energy conversion device can realize the DC / AC function. The energy conversion device can convert the DC power (such as Figure 1 The V HV ) into AC (such as Figure 1 The V ac ), the AC end is output from the first AC end and the second AC end to the AC load (a load that supports AC power supply), thereby powering the AC load.

[0057] When the energy conversion device operates in forward charging mode, it can realize AC / DC functions. The energy conversion device can convert the AC power at the first AC terminal and the second AC terminal into DC power, and output the DC power from the first DC terminal and the second DC terminal to the positive and negative poles of the battery, thereby charging the battery.

[0058] The rectifier module 10 can perform bidirectional rectification. For example, when the energy conversion device operates in forward charging mode, the rectifier module 10 can convert the AC voltage between the first and second AC terminals into a DC voltage (e.g., a mantou wave, which is a waveform obtained by half-wave rectification and can be a waveform obtained by inverting the negative half-cycle of a sine wave) and output this DC voltage to the first and second terminals of the first DC / DC module 21. When the energy conversion device operates in reverse discharge mode, the rectifier module 10 can also convert the DC voltage between the first and second terminals of the first DC / DC module 21 into an AC voltage and output this AC voltage to the first and second AC terminals.

[0059] The first DC / DC module 21 can convert one DC voltage to another. For example, when the energy conversion device is operating in forward charging mode, the first DC / DC module 21 can convert a pulsating DC waveform (e.g., a steamed bun waveform) between the third and fourth terminals of the rectifier module 10 into a linear DC waveform, and output this linear DC waveform to the first and second DC terminals. When the energy conversion device is operating in reverse discharge mode, the first DC / DC module 21 can also convert the linear DC waveform between the first and second DC terminals into a pulsating DC waveform, and output this pulsating DC waveform to the third and fourth terminals of the rectifier module 10.

[0060] A two-stage architecture of PFC module and DC / DC module is adopted, and electrolytic capacitors (also called bus capacitors) need to be added between the PFC module and the DC / DC module for decoupling.

[0061] In the embodiments of the present application, the energy conversion device adopts a single-stage topology, compared with the two-stage architecture adopting a PFC module and a DC / DC module, one DC / DC converter can be reduced, thereby reducing the number of active devices. The energy conversion device does not need to increase the electrolytic capacitor, improves the power density of the energy conversion device, thereby reducing the cost and volume of the energy conversion device. The control module can determine the duty cycle of the switch tube in the first DC / DC module according to the first sampling voltage or the second sampling voltage, control the conduction or turn-off of the rectifier tube in the rectifier module, to realize the direct current to alternating current function of the energy conversion device, so as to make the energy conversion device work in the reverse discharge mode, and expand the application scenarios of the energy conversion device.

[0062] The at least one DC / DC module is connected in an interleaved and parallel manner, improves the output power of the energy conversion device, and can be applied to high-power scenarios.

[0063] As shown in Figure 1 The first DC / DC module includes a first capacitor C1, a second capacitor C2, a third capacitor C3, a first switch tube S1, a second switch tube S2, a first inductor L1, a second inductor L2, and a transformer T1. The first end of the first capacitor C1 is connected to the first end of the first inductor L1 and the third end of the rectifier module 10. The second end of the first inductor L1 is connected to the first end of the second capacitor C2 and the first end of the first switch tube S1. The second end of the second capacitor C2 is connected to the first end of the second inductor L2 and the first end of the primary winding of the transformer T1. The second end of the first capacitor C1 is connected to the second end of the first switch tube S1, the second end of the second inductor L2, the second end of the primary winding, and the fourth end of the rectifier module 10. The first end of the secondary winding of the transformer T1 is connected to the first end of the second switch tube S2. The second end of the second switch tube S2 is connected to the first end of the third capacitor C3 and the first DC terminal. The second end of the secondary winding is connected to the second end of the third capacitor C3 and the second DC terminal.

[0064] As shown in Figure 1 The diode connected in parallel between the first end of the first switch tube S1 and the second end of the first switch tube S1 is a parasitic diode or a body diode, which can prevent the first switch tube S1 from being damaged due to overvoltage, electrostatic discharge or other transient voltage. The diode connected in parallel between the first end of the second switch tube S2 and the second end of the second switch tube S2 is a parasitic diode or a body diode, which can prevent the second switch tube S2 from being damaged due to overvoltage, electrostatic discharge or other transient voltage.

[0065] In this embodiment, the first DC / DC module 21 includes two switching transistors: a first switching transistor S1 and a second switching transistor S2. A conventional single-stage alternating current / direct current (AC / DC) module includes at least two bridge arms (at least four switching transistors). Compared to conventional single-stage AC / DC modules, the first DC / DC module 21 in this embodiment can reduce the number of switching transistors, thereby further reducing the cost and size of the energy conversion device.

[0066] in, Figure 1 i in L1 is the current on the first inductor L1, i L2 is the current on the second inductor L2, i s2 is the current passing through the second switch tube S2.

[0067] The transformer T1 may be an isolation transformer, which can achieve isolation between the AC end (the first AC end and the second AC end) and the DC end (the first DC end and the second DC end).

[0068] Optionally, the second inductor L2 is the magnetizing inductor in the primary winding of the transformer T1.

[0069] In the embodiment of the present application, the second inductor L2 can reuse the magnetizing inductance in the primary winding of the transformer T1, thereby improving the integration of the first DC / DC module 21, reducing the cost and volume of the first DC / DC module 21, and further reducing the cost and volume of the energy conversion device.

[0070] like Figure 1 As shown, the rectifier module 10 includes a first rectifier tube Q1, a second rectifier tube Q2, a third rectifier tube Q3 and a fourth rectifier tube Q4. The first end of the first rectifier tube Q1 is connected to the first end of the second rectifier tube Q2 and the first end of the first DC / DC module 21. The second end of the first rectifier tube Q1 is connected to the first end of the third rectifier tube Q3 and the first AC end. The second end of the second rectifier tube Q2 is connected to the first end of the fourth rectifier tube Q4 and the second AC end. The second end of the third rectifier tube Q3 is connected to the second end of the fourth rectifier tube Q4 and the second end of the first DC / DC module 21.

[0071] In the embodiment of the present application, the rectifier module 10 includes four rectifier tubes, and the control module 30 can control the conduction or turn-off of the rectifier tubes in the rectifier module 10. The rectifier tubes are different from simple diodes, so that the rectifier module 10 can support bidirectional rectification, so that the energy conversion device can work in a forward charging mode (the energy conversion device can convert the alternating current of the first alternating current end and the second alternating current end into direct current, and the direct current is output from the first direct current end and the second direct current end to the positive and negative poles of the battery, thereby realizing charging of the battery), and can also work in a reverse discharge mode (the energy conversion device can convert the direct current of the first direct current end and the second direct current end into alternating current, and the alternating current end is output from the first alternating current end and the second alternating current end to an alternating current load (a load supporting alternating current power supply), thereby realizing power supply for the alternating current load), thereby expanding the application scenarios of the energy conversion device.

[0072] Optionally, each rectifier tube includes an Insulate-Gate Bipolar Transistor (IGBT) or a Metal-Oxide-Semiconductor Field-Effect Transistor (MOSFET).

[0073] In the embodiment of the present application, the MOSFET can also be referred to as a MOS tube or a MOS transistor. The rectifier tube can be an IGBT or a MOS tube. The use of an IGBT for the rectifier tube can reduce the cost, and the use of a MOS tube for the rectifier tube can reduce the conduction loss.

[0074] Optionally, the first switch tube S1 and the second switch tube S2 can both be an IGBT or a MOSFET.

[0075] Figure 1 The rectifier tube of the first switch tube S1 and the second switch tube S2 is taken as an example, Figure 1 The first switch tube S1 and the second switch tube S2 are taken as an example of an N-type MOS transistor. The N-type MOS transistor can be referred to as an NOMS tube. The MOSFET can be a silicon carbide (SiC) MOSFET or a gallium nitride (GaN) MOSFET. The silicon carbide MOSFET is a MOSFET using silicon carbide material, and the gallium nitride MOSFET is a MOSFET using gallium nitride material.

[0076] The first end of each rectifier tube is connected to the negative pole of a diode connected in parallel with the rectifier tube, and the second end of each rectifier tube is connected to the positive pole of a diode connected in parallel with the rectifier tube. The first end of the first rectifier tube Q1 is connected to the negative pole of a diode connected in parallel with the first rectifier tube Q1, the second end of the first rectifier tube Q1 is connected to the positive pole of a diode connected in parallel with the first rectifier tube Q1; the first end of the second rectifier tube Q2 is connected to the negative pole of a diode connected in parallel with the second rectifier tube Q2, the second end of the second rectifier tube Q2 is connected to the positive pole of a diode connected in parallel with the second rectifier tube Q2; the first end of the third rectifier tube Q3 is connected to the negative pole of a diode connected in parallel with the third rectifier tube Q3, the second end of the third rectifier tube Q3 is connected to the positive pole of a diode connected in parallel with the third rectifier tube Q3; the first end of the fourth rectifier tube Q4 is connected to the negative pole of a diode connected in parallel with the fourth rectifier tube Q4, the second end of the fourth rectifier tube Q4 is connected to the positive pole of a diode connected in parallel with the fourth rectifier tube Q4.

[0077] The diode connected in parallel with each rectifier tube can be a body diode or a parasitic diode of the rectifier tube. The diode can function as a freewheeling diode.

[0078] Optionally, the control module 30 determines the duty ratio of a switch tube in the first DC / DC module 21 according to the first sampling voltage or the second sampling voltage, controls the conduction or turn-off of the rectifier tube in the rectifier module 10, so as to realize the direct current to alternating current function of the energy conversion device, including:

[0079] The control module 30 determines the duty ratio of a switch tube in the first DC / DC module 21 according to the first sampling voltage or the second sampling voltage, and a first sampling current, controls the conduction or turn-off of the rectifier tube in the rectifier module 10, so as to realize the direct current to alternating current function of the energy conversion device, the first sampling current being a current on the first inductor L1.

[0080] In the embodiment of the present application, the first sampling voltage is a sampling voltage output by the energy conversion device when the energy conversion device works in the reverse discharge mode, and the control module 30 can adjust the voltage output by the energy conversion device according to the sampling voltage output by the energy conversion device when the energy conversion device works in the reverse discharge mode, so as to ensure the stability of the voltage output by the energy conversion device. The first sampling current is a sampling current on the first inductor L1, and since the current on the first inductor L1 changes with the load change of the output end (the first alternating current end and the second alternating current end) of the energy conversion device, the control module 30 can adjust the current on the first inductor L1 according to the sampling current on the first inductor L1, so that the dynamic characteristics of the load of the output end of the energy conversion device are improved and the current limiting effect is achieved. When the energy conversion device works in the reverse discharge mode, the sampling current on the first inductor L1 is the sampling current output by the energy conversion device. The control module 30 determines the duty cycle of the switching tube in the first DC / DC module 21 according to the first sampling voltage or the second sampling voltage and the first sampling current, so as to ensure the stability of the voltage and the current output by the energy conversion device when the energy conversion device works in the reverse discharge mode.

[0081] Optionally, the control module 30 determines the duty cycle of the switching tube in the first DC / DC module 21 according to the first sampling voltage or the second sampling voltage and the first sampling current, and controls the conduction or turn-off of the rectifier tube in the rectifier module 10, so as to realize the direct current to alternating current function of the energy conversion device, including:

[0082] The control module 30 determines the first reference current according to the first sampling voltage or the second sampling voltage and the first reference voltage, and determines the duty cycle of the second switching tube S2 according to the first sampling current and the first reference current.

[0083] When the required alternating current voltage between the first alternating current end and the second alternating current end is a positive half wave, the control module 30 controls the first rectifier tube Q1 and the fourth rectifier tube Q4 to be turned on, and the second rectifier tube Q2 and the third rectifier tube Q3 to be turned off.

[0084] When the required alternating current voltage between the first alternating current end and the second alternating current end is a negative half wave, the control module 30 controls the second rectifier tube Q2 and the third rectifier tube Q3 to be turned on, and the first rectifier tube Q1 and the fourth rectifier tube Q4 to be turned off.

[0085] In the embodiment of the present application, the first reference voltage is the instantaneous value of the required alternating current voltage (the alternating current voltage required to be output between the first alternating current end and the second alternating current end) currently set by the energy conversion device, and the first sampling voltage is the voltage obtained by sampling the first end of the rectifier module 10 and the second end of the rectifier module 10 through the voltage sampling module, as shown as V Figure 2 ​ac The first sampling current can be a sampling current on the first inductor L1, as shown by i Figure 2 L1 The second sampling voltage can be a sampling voltage between the first end of the first DC / DC module 21 and the second end of the first DC / DC module 21, as shown by V Figure 2 rec .

[0086] The duty cycle of the second switch S2 can be used to adjust the amplitude of the voltage between the first AC end and the second AC end. For example, in the case where the first sampling voltage is greater than the first reference voltage, the duty cycle of the second switch S2 can be reduced, thereby reducing the voltage across the first capacitor C1 (as shown by V Figure 2 rec ), and further reducing the amplitude of the voltage between the first AC end and the second AC end, so that the amplitude of the voltage between the first AC end and the second AC end is close to or equal to the first reference voltage. In the case where the first sampling voltage is less than the first reference voltage, the duty cycle of the second switch S2 can be increased, thereby increasing the voltage across the first capacitor C1, and further increasing the amplitude of the voltage between the first AC end and the second AC end, so that the amplitude of the voltage between the first AC end and the second AC end is close to or equal to the first reference voltage.

[0087] The period of the required AC voltage between the first AC end and the second AC end can be set as required. For example, the period of the required AC voltage is 20 milliseconds (the period is 50 Hz), the amplitude of the required AC voltage is 311 V, and the effective value of the required AC voltage is 220 V.

[0088] The control module 30 can control the conduction time (for example, 10 milliseconds) of the first rectifier Q1 and the fourth rectifier Q4, so that the first AC end and the second AC end are the positive half wave of the required AC voltage. The control module 30 can control the conduction time (for example, 10 milliseconds) of the second rectifier Q2 and the third rectifier Q3, so that the first AC end and the second AC end are the negative half wave of the required AC voltage.

[0089] Please refer to Figure 2 , Figure 2 is a structure diagram of a control module in a reverse discharge mode provided by an embodiment of the present application. As shown in Figure 2 , in the case where the control module 30 determines the first reference current according to the first sampling voltage and the first reference voltage, and determines the duty cycle of the second switch S2 according to the first sampling current and the first reference current, the control module 30 includes a first voltage control loop and a first current control loop.

[0090] ​​​In the embodiment of the present application, the first voltage control loop is used to control the first reference voltage (such as Figure 2 The V ac_Ref ) and the first sampling voltage (such as Figure 2 The V ac ) performs loop calculation on the result after subtraction, and outputs the first loop current. The first reference current (such as Figure 2 The i shown L1_Ref ) is the absolute value of the first loop current. The regulator in the first voltage control loop can be a proportional integral (PI) regulator or a proportional resonant (PR) regulator, which is used to adjust (V ac_Ref -V ac ) to perform loop calculation and obtain the first loop current. Figure 2 In the example, the regulator in the first voltage control loop is a PI regulator. Abs is an absolute value module used to take the absolute value of the first loop current to obtain the first reference current (such as Figure 2 The i shown L1_Ref ).

[0091] The first current control loop is used to control the first reference current and the first sampling current (such as Figure 2 The i shown L1 ) is subtracted and the result is looped to calculate and output the duty cycle of the second switch tube S2 (such as Figure 3 The regulator in the first current control loop may be a proportional integral (PI) regulator or a proportional resonant (PR) regulator, which is used to control (i L1_Ref -i L1 ) performs loop calculation to obtain the duty cycle d2 of the second switch tube S2. Figure 3 In the embodiment, the regulator in the first current control loop is exemplified by a PI regulator.

[0092] In the embodiment of the present application, the first voltage control loop is a voltage outer loop, and the first current control loop is a current inner loop.

[0093] Figure 3The wave driving module in the embodiment can be a pulse width modulation (PWM) module. The wave driving module can generate a wave signal for each switch tube (the first switch tube S1 and the second switch tube S2) according to the duty cycle of the second switch tube S2, and then amplify and isolate the wave signal of each switch tube to generate a drive signal for each switch tube. The drive signal of the switch tube is used to drive the switch tube to be turned on or off. Figure 3 As shown, the driving signal of S1 is the driving signal of the first switch tube S1, and the driving signal of S2 is the driving signal of the second switch tube S2.

[0094] See also Figure 3 , Figure 3 This is a schematic diagram of the structure of another control module in a reverse discharge mode provided by an embodiment of the present application. When the control module 30 determines a first reference current based on a second sampled voltage and a first reference voltage, and determines a duty cycle of the second switch S2 based on the first sampled current and the first reference current, the control module includes: a second voltage control loop and a second current control loop;

[0095] The second voltage control loop is configured to perform loop calculation on a result of subtracting the absolute value of the first reference voltage from the second sampled voltage, and output a first reference current;

[0096] The second current control loop is used to perform loop calculation on a result of subtracting the first reference current from the first sampling current, and output a duty cycle of the second switch tube.

[0097] In the embodiment of the present application, the second voltage control loop is used to control the first reference voltage (such as Figure 3 The V ac_Ref ) takes its absolute value, and the second sampling voltage (such as Figure 3 The V rec ) is subtracted and the result is looped and the first reference current is output (e.g. Figure 4 The i shown L1_Ref The regulator in the second voltage control loop can be a proportional integral (PI) regulator or a proportional resonant (PR) regulator, which is used to adjust (V ac_Ref Absolute value of -V rec ) performs loop calculation to obtain the first reference current. Figure 4 In the embodiment, the regulator in the second voltage control loop is a PI regulator. Abs is an absolute value module, which is used to obtain the absolute value of the first reference voltage.

[0098] The second current control loop is used to control the first reference current and the first sampling current (such as Figure 4 The i shown L1 ) is subtracted and the result is looped to calculate and output the duty cycle of the second switch tube S2 (such as Figure 4 The regulator in the second current control loop may be a proportional integral (PI) regulator or a proportional resonant (PR) regulator, which is used to control (i L1_Ref -i L1 ) performs loop calculation to obtain the duty cycle d2 of the second switch tube S2. Figure 4 In the embodiment, the regulator in the second current control loop is exemplified by a PI regulator.

[0099] In the embodiment of the present application, the second voltage control loop is a voltage outer loop, and the second current control loop is a current inner loop.

[0100] See also Figure 4 , Figure 4 This is a structural diagram of a control module in another reverse discharge mode provided by an embodiment of the present application. Figure 4 As shown, in the case where the control module 30 determines the duty cycle of the switch tube in the first DC / DC module according to the first sampled voltage, the control module 30 includes a third voltage control loop.

[0101] In the embodiment of the present application, the third voltage control loop is used to control the first reference voltage (such as Figure 5 The V ac_Ref ) and the first sampling voltage (such as Figure 5 The V ac ) is subtracted and the result is looped to calculate and output the duty cycle of the second switch tube S2 (such as Figure 5 d2 shown).

[0102] Figure 5 The wave driving module in the embodiment can be a PWM module. The wave driving module can generate a wave signal for each switch tube (the first switch tube S1 and the second switch tube S2) according to the duty cycle of the second switch tube S2, and then amplify and isolate the wave signal of each switch tube to generate a drive signal for each switch tube. The drive signal of the switch tube is used to drive the switch tube to be turned on or off. Figure 5 As shown, the driving signal of S1 is the driving signal of the first switch tube S1, and the driving signal of S2 is the driving signal of the second switch tube S2.

[0103] In the embodiment of the present application, the duty cycle of the second switch tube S2 can be determined by a voltage control loop without using a current control loop, thereby reducing the complexity of the control module 30.

[0104] See also Figure 5 , Figure 5 This is a structural diagram of a control module in another reverse discharge mode provided by an embodiment of the present application. Figure 5 As shown, in the case where the control module determines the duty cycle of the switch tube in the first DC / DC module according to the second sampled voltage, the control module 30 includes a fourth voltage control loop.

[0105] In the embodiment of the present application, the fourth voltage control loop is used to control the first reference voltage (such as Figure 6 The V ac_Ref ) and the absolute value of the second sampling voltage (such as Figure 6 The V rec ) is subtracted and the result is looped to calculate and output the duty cycle of the second switch tube S2 (such as Figure 6 d2 shown).

[0106] Figure 7 The wave driving module in the embodiment can be a PWM module. The wave driving module can generate a wave signal for each switch tube (the first switch tube S1 and the second switch tube S2) according to the duty cycle of the second switch tube S2, and then amplify and isolate the wave signal of each switch tube to generate a drive signal for each switch tube. The drive signal of the switch tube is used to drive the switch tube to be turned on or off. Figure 7 As shown, the driving signal of S1 is the driving signal of the first switch tube S1, and the driving signal of S2 is the driving signal of the second switch tube S2.

[0107] In the embodiment of the present application, the duty cycle of the second switch tube S2 can be determined by a voltage control loop without using a current control loop, thereby reducing the complexity of the control module 30.

[0108] See also Figure 7 , Figure 7 Schematic diagram of the waveform of the AC voltage outputted from the first AC terminal and the second AC terminal of an energy conversion device provided in an embodiment of the present application. Figures 1 to 5 As shown, the inverted AC voltage is the AC voltage output by the first AC terminal and the second AC terminal of the energy conversion device. The amplitude of the AC voltage is 311V and the frequency of the AC voltage is 50Hz.

[0109] See also ​ , ​ This is a schematic diagram of the structure of a vehicle provided in an embodiment of the present application. ​As shown, the vehicle can include the energy conversion device 100 and the battery 200. The battery 200 can be a power battery on the vehicle. The vehicle can be an electric vehicle. The energy conversion device 100 can be used to convert alternating current into direct current to charge the battery 200. The battery 200 can input direct current into the energy conversion device 100, and the energy conversion device 100 converts the input direct current into alternating current to supply power to an alternating current load.

[0110] ​ The specific structure and working principle of the energy conversion device 100 in the above embodiments can refer to the above description of the energy conversion device 100. ​ The embodiments shown in the above description will not be repeated here.

[0111] In the above embodiments, the description of each embodiment has its own focus, and the parts not described in detail in a certain embodiment can refer to the relevant description of other embodiments.

[0112] In the several embodiments provided in the present application, it should be understood that the disclosed energy conversion device and vehicle can be implemented in other ways. For example, the energy conversion device embodiments described above are merely schematic, for example, the division of units is only a logical functional division, and in actual implementation, there can be another division manner, for example, a plurality of units or components can be combined or integrated into another system, or some features can be ignored or not executed.

Claims

1. An energy conversion device, characterized by, The energy conversion device comprises a rectifier module, at least one DC / DC module and a control module, a first end of the rectifier module is connected to a first alternating current end, a second end of the rectifier module is connected to a second alternating current end, a third end of the rectifier module is connected to a first end of the first DC / DC module, a fourth end of the rectifier module is connected to a second end of the first DC / DC module, a third end of the first DC / DC module is connected to a first direct current end, and a fourth end of the first DC / DC module is connected to a second direct current end; the first DC / DC module is any one of the at least one DC / DC module; When the energy conversion device works in a reverse discharge mode, the control module determines a duty cycle of a switch tube in the first DC / DC module according to a first sampling voltage or a second sampling voltage, controls conduction or turn-off of a rectifier tube in the rectifier module, and realizes a direct current to alternating current function of the energy conversion device; the first sampling voltage is a sampling voltage between the first end of the rectifier module and the second end of the rectifier module, and the second sampling voltage is a sampling voltage between the first end of the first DC / DC module and the second end of the first DC / DC module.

2. The energy conversion device of claim 1, wherein, The first DC / DC module comprises a first capacitor, a second capacitor, a third capacitor, a first switch tube, a second switch tube, a first inductor, a second inductor and a transformer; a first end of the first capacitor is connected to a first end of the first inductor and a third end of the rectifier module, a second end of the first inductor is connected to a first end of the second capacitor and a first end of the first switch tube, a second end of the second capacitor is connected to a first end of the second inductor and a first end of a primary winding of the transformer, a second end of the first capacitor is connected to a second end of the first switch tube, a second end of the second inductor, a second end of the primary winding and a fourth end of the rectifier module; a first end of a secondary winding of the transformer is connected to a first end of the second switch tube, a second end of the second switch tube is connected to a first end of the third capacitor and the first direct current end, and a second end of the secondary winding is connected to a second end of the third capacitor and the second direct current end.

3. The energy conversion device of claim 2, wherein, The rectifier module comprises a first rectifier tube, a second rectifier tube, a third rectifier tube and a fourth rectifier tube, a first end of the first rectifier tube is connected to a first end of the second rectifier tube and a first end of the first DC / DC module, a second end of the first rectifier tube is connected to a first end of the third rectifier tube and the first alternating current end, a second end of the second rectifier tube is connected to a first end of the fourth rectifier tube and the second alternating current end, and a second end of the third rectifier tube is connected to a second end of the fourth rectifier tube and a second end of the first DC / DC module.

4. The energy conversion device of claim 3, wherein, The control module determines a duty cycle of a switch tube in the first DC / DC module according to a first sampling voltage or a second sampling voltage, controls conduction or turn-off of a rectifier tube in the rectifier module, and realizes a direct current to alternating current function of the energy conversion device, comprising: The control module determines the duty cycle of the switch tube in the first DC / DC module according to the first sampling voltage or the second sampling voltage and the first sampling current, controls the turn-on or turn-off of the rectifier tube in the rectifier module, so as to realize the direct current to alternating current function of the energy conversion device.

5. The energy conversion device of claim 4, wherein, The control module determines the duty cycle of the switch tube in the first DC / DC module according to the first sampling voltage or the second sampling voltage and the first sampling current, controls the turn-on or turn-off of the rectifier tube in the rectifier module, so as to realize the direct current to alternating current function of the energy conversion device. The control module determines the first reference current according to the first sampling voltage or the second sampling voltage and the first reference voltage, and determines the duty cycle of the second switch tube according to the first sampling current and the first reference current; In the case that the required alternating voltage between the first alternating terminal and the second alternating terminal is a positive half wave, the control module controls the first rectifier tube and the fourth rectifier tube to be turned on, and the second rectifier tube and the third rectifier tube to be turned off; In the case that the required alternating voltage between the first alternating terminal and the second alternating terminal is a negative half wave, the control module controls the second rectifier tube and the third rectifier tube to be turned on, and the first rectifier tube and the fourth rectifier tube to be turned off.

6. The energy conversion device of claim 5, wherein, In the case that the control module determines the first reference current according to the first sampling voltage and the first reference voltage, and determines the duty cycle of the second switch tube according to the first sampling current and the first reference current, the control module comprises a first voltage control loop and a first current control loop; The first voltage control loop is configured to perform loop calculation on the result of subtraction between the first reference voltage and the first sampling voltage, and output a first loop current, wherein the first reference current is the absolute value of the first loop current; The first current control loop is configured to perform loop calculation on the result of subtraction between the first reference current and the first sampling current, and output the duty cycle of the second switch tube.

7. The energy conversion device of claim 5, wherein, In the case that the control module determines the first reference current according to the second sampling voltage and the first reference voltage, and determines the duty cycle of the second switch tube according to the first sampling current and the first reference current, the control module comprises a second voltage control loop and a second current control loop; The second voltage control loop is configured to perform loop calculation on the result of subtraction between the absolute value of the first reference voltage and the second sampling voltage, and output the first reference current; The second current control loop is configured to perform loop calculation on the result of subtraction between the first reference current and the first sampling current, and output the duty cycle of the second switch tube.

8. The energy conversion device of claim 5, wherein, In the case that the control module determines the duty cycle of the switch tube in the first DC / DC module according to the first sampling voltage, the control module comprises a third voltage control loop; The third voltage control loop is configured to perform loop calculation on a result of subtraction between the first reference voltage and the first sampling voltage, and output a duty cycle of the second switch tube.

9. The energy conversion device of claim 5, wherein, In the case that the control module determines the duty cycle of the switch tube in the first DC / DC module according to the second sampling voltage, the control module comprises a fourth voltage control loop; The fourth voltage control loop is configured to perform loop calculation on a result of subtraction between an absolute value of the first reference voltage and the second sampling voltage, and output the duty cycle of the second switch tube.

10. A vehicle characterized by comprising: The energy conversion device is used for converting direct current of the battery into alternating current to realize a reverse discharge function.

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