Mobile energy storage vehicle-mounted AC / DC converter and current conversion control method

Abstract

The present application provides a mobile energy storage vehicle-mounted AC / DC converter and a current conversion control method, which relates to the field of new energy technology. The mobile energy storage vehicle-mounted AC / DC converter includes: a T-type three-level inverter topology structure, a first switch, a second switch, and a third switch; one end of the first switch, the second switch, and the third switch are respectively connected to the A-phase, B-phase, and C-phase output ends of the T-type three-level inverter topology structure, and the other end is respectively used as the A-phase, B-phase, and C-phase output ends of the mobile energy storage vehicle-mounted AC / DC converter; when the first switch and the third switch are both closed and the second switch is disconnected, the mobile energy storage vehicle-mounted AC / DC converter outputs a DC voltage; when the first switch, the second switch, and the third switch are all closed, the mobile energy storage vehicle-mounted AC / DC converter outputs an AC voltage. Through this application, the mobile energy storage vehicle can meet the output AC or DC requirements and reduce power loss.

Description

Technical Field

[0001] The present application relates to the field of new energy technology, and in particular to a mobile energy storage vehicle-mounted AC / DC converter and a current conversion control method. Background Art

[0002] With the growing demand for renewable energy, the application prospects of mobile energy storage vehicles in power storage and dispatch are gradually emerging. Mobile energy storage vehicles have the advantages of being green, environmentally friendly, mobile, multifunctional and intelligent. They can provide continuous power support to various users by efficiently storing and outputting electricity in the event of power shortages. Mobile energy storage vehicles are mainly used in the following scenarios: emergency power supply, outdoor activities, power supply for important occasions, emergency rescue of electric vehicles, outdoor emergency power supply, etc. Mobile energy storage vehicles carry batteries to output power to the outside, which is generally used for emergency power supply. According to power demand, it is divided into DC power supply and AC power supply.

[0003] In the prior art, if AC power supply is required, a DC / AC device needs to be added between the battery and the load to control the AC voltage and energy; correspondingly, if DC power supply is required, a DC / DC device needs to be added between the battery and the load to control the DC voltage and energy. Therefore, if both AC and DC power supply requirements need to be met, two voltage conversion devices, DC / AC devices and DC / DC devices, need to be configured on the mobile energy storage vehicle respectively.

[0004] As a result, the capacity of the energy storage batteries on the mobile energy storage vehicle will be squeezed and the emergency power supply time will be compressed, leading to energy waste. Summary of the invention

[0005] The embodiments of the present application provide a mobile energy storage vehicle-mounted AC / DC converter and a current conversion control method to achieve compatible output of AC voltage and DC voltage, thereby solving the problem of energy waste.

[0006] In a first aspect, an embodiment of the present application provides a mobile energy storage vehicle-mounted AC / DC converter, including: a T-type three-level inverter topology structure, a first switch, a second switch, and a third switch;

[0007] One end of the first switch is connected to the A-phase output end of the T-type three-level inverter topology structure, and the other end of the first switch serves as the A-phase output end of the mobile energy storage vehicle-mounted AC / DC converter;

[0008] One end of the second switch is connected to the B-phase output end of the T-type three-level inverter topology structure, and the other end of the second switch serves as the B-phase output end of the mobile energy storage vehicle-mounted AC / DC converter;

[0009] One end of the third switch is connected to the C-phase output end of the T-type three-level inverter topology structure, and the other end of the third switch serves as the C-phase output end of the mobile energy storage vehicle-mounted AC / DC converter;

[0010] When the first switch and the third switch are both closed and the second switch is open, the mobile energy storage vehicle-mounted AC / DC converter outputs a DC voltage; when the first switch, the second switch and the third switch are all closed, the mobile energy storage vehicle-mounted AC / DC converter outputs an AC voltage.

[0011] In a possible implementation manner, the device further includes: a fourth switch, one end of the fourth switch being connected to the midpoint of the filter capacitor of the T-type three-level inverter topology structure, and the other end of the fourth switch being connected to the midpoint of the three levels of the T-type three-level inverter topology structure;

[0012] When the fourth switch is closed, the fourth switch tube of phase A is turned off, the second switch tube is turned on, the first switch tube and the third switch tube are driven complementarily, and the first switch tube of phase C is turned off, the third switch tube is turned on, and the fourth switch tube and the second switch tube are driven complementarily;

[0013] When the fourth switch is disconnected, the fourth switch tube of phase A is turned off, the second switch tube is turned on, and the first switch tube and the third switch tube are driven complementarily, and the first switch tube of phase C is turned off, the third switch tube is turned on, and the fourth switch tube and the second switch tube are driven complementarily, and the first switch tube of phase A and the fourth switch tube of phase C are driven alternately.

[0014] In a possible implementation manner, the three-level inverter of the T-type three-level inverter topology structure adopts a filter output, and a filter capacitor in the filter adopts a non-polarized capacitor.

[0015] In a second aspect, an embodiment of the present application provides a current conversion control method for controlling the above first aspect and / or various possible mobile energy storage vehicle-mounted AC / DC converters of the first aspect, the method comprising:

[0016] Obtain voltage output requirements, which include DC voltage output and AC voltage output;

[0017] If the voltage output requirement is a DC voltage output, the first switch and the third switch are controlled to be closed, and the second switch is controlled to be opened;

[0018] If the voltage output requirement is an AC voltage output, the first switch, the second switch and the third switch are all controlled to be closed.

[0019] In a possible implementation, controlling the first switch and the third switch to be closed, and controlling the second switch to be opened, includes:

[0020] If the fourth switch is controlled to be closed, in the first period of the switching cycle, the first switch is controlled to be closed, the first switch tube of phase A is turned on, the third switch tube of phase A is turned off, and the first input capacitor of the T-type three-level inverter topology structure charges the first inductor and the first filter capacitor of phase A;

[0021] The third switch is controlled to be closed, the second switch tube of phase C is turned off, the fourth switch tube of phase C is turned on, and the second input capacitor of the T-type three-level inverter topology structure charges the first inductor and the third filter capacitor of phase C.

[0022] In a possible implementation, the method further includes:

[0023] In the second period of the switching cycle, the first switch is controlled to be closed, the first switch tube of phase A is turned off, the third switch tube of phase A is turned on, and the first filter capacitor freewheels the first inductor of phase A;

[0024] The third switch is controlled to be closed, the second switch tube of the C phase is turned on, the fourth switch tube of the C phase is turned off, and the third filter capacitor continues the current flow of the first inductor of the C phase.

[0025] In a possible implementation, controlling the first switch and the third switch to be closed, and controlling the second switch to be opened, includes:

[0026] If the fourth switch is controlled to be disconnected, when the duty cycle is less than the first threshold, in the first period of the switching cycle, the first switch and the third switch are controlled to be closed, the first switch tube of phase A is turned on, the third switch tube of phase A is turned off, the second switch tube of phase C is turned on, and the fourth switch tube of phase C is turned off, and the first input capacitor charges the first inductor and the first filter capacitor of phase A, the first inductor and the third filter capacitor of phase C;

[0027] In the second period of the switching cycle, the first switch and the third switch are controlled to be closed, the first switch tube of phase A is turned off, the third switch tube of phase A is turned on, the second switch tube of phase C is turned on, and the fourth switch tube of phase C is turned off, and the first filter capacitor and the third filter capacitor continue the current for the first inductor of phase A and the first inductor of phase C.

[0028] In a possible implementation, the method further includes:

[0029] In the third period of the switching cycle, the first switch and the third switch are controlled to be closed, the first switch tube of phase A is turned off, the third switch tube of phase A is turned on, the second switch tube of phase C is turned off, and the fourth switch tube of phase C is turned on, and the second input capacitor charges the first inductor and the first filter capacitor of phase A, the first inductor and the third filter capacitor of phase C;

[0030] In the fourth time period of the switching cycle, the first switch and the third switch are controlled to be closed, the first switch tube of phase A is turned off, the third switch tube of phase A is turned on, the second switch tube of phase C is turned on, and the fourth switch tube of phase C is turned off, and the first filter capacitor and the third filter capacitor continue the current for the first inductor of phase A and the first inductor of phase C.

[0031] In a possible implementation, the method further includes:

[0032] When the duty cycle is greater than the first threshold, in the first period of the switching cycle, the first switch and the third switch are controlled to be closed, the first switch tube of phase A is turned on, the third switch tube of phase A is turned off, the second switch tube of phase C is turned off, and the fourth switch tube of phase C is turned on, and the first input capacitor and the second input capacitor charge the first inductor and the first filter capacitor of phase A, the first inductor and the third filter capacitor of phase C;

[0033] In the second period of the switching cycle, the first switch and the third switch are controlled to be closed, the first switch tube of phase A is turned on, the third switch tube of phase A is turned off, the second switch tube of phase C is turned on, and the fourth switch tube of phase C is turned off, and the first input capacitor, the first filter capacitor, and the third filter capacitor are used to freewheel the first inductor of phase A and the first inductor of phase C.

[0034] In a possible implementation, the method further includes:

[0035] In the third period of the switching cycle, the first switch and the third switch are controlled to be closed, the first switch tube of phase A is turned on, the third switch tube of phase A is turned off, the second switch tube of phase C is turned off, and the fourth switch tube of phase C is turned on, and the first input capacitor and the second input capacitor charge the first inductor and the first filter capacitor of phase A, the first inductor and the third filter capacitor of phase C;

[0036] In the fourth time period of the switching cycle, the first switch and the third switch are controlled to be closed, the first switch tube of phase A is turned off, the third switch tube of phase A is turned on, the second switch tube of phase C is turned off, and the fourth switch tube of phase C is turned on, and the second input capacitor, the first filter capacitor, and the third filter capacitor continue the current for the first inductor of phase A and the first inductor of phase C.

[0037] In a third aspect, an embodiment of the present application provides a variable current control device, comprising:

[0038] An acquisition module is used to acquire voltage output requirements, where the voltage output requirements include DC voltage output and AC voltage output;

[0039] A first control module, configured to control the first switch and the third switch to be closed, and control the second switch to be opened, if the voltage output requirement is a DC voltage output;

[0040] The second control module is used to control the first switch, the second switch and the third switch to be closed if the voltage output requirement is an AC voltage output.

[0041] In a possible implementation manner, the first control module is specifically configured to:

[0042] If the fourth switch is controlled to be closed, in the first period of the switching cycle, the first switch is controlled to be closed, the first switch tube of phase A is turned on, the third switch tube of phase A is turned off, and the first input capacitor of the T-type three-level inverter topology structure charges the first inductor and the first filter capacitor of phase A;

[0043] The third switch is controlled to be closed, the second switch tube of phase C is turned off, the fourth switch tube of phase C is turned on, and the second input capacitor of the T-type three-level inverter topology structure charges the first inductor and the third filter capacitor of phase C.

[0044] In a possible implementation manner, the first control module is further configured to:

[0045] In the second period of the switching cycle, the first switch is controlled to be closed, the first switch tube of phase A is turned off, the third switch tube of phase A is turned on, and the first filter capacitor freewheels the first inductor of phase A;

[0046] The third switch is controlled to be closed, the second switch tube of the C phase is turned on, the fourth switch tube of the C phase is turned off, and the third filter capacitor continues the current flow of the first inductor of the C phase.

[0047] In a possible implementation manner, the first control module is further configured to:

[0048] If the fourth switch is controlled to be disconnected, when the duty cycle is less than the first threshold, in the first period of the switching cycle, the first switch and the third switch are controlled to be closed, the first switch tube of phase A is turned on, the third switch tube of phase A is turned off, the second switch tube of phase C is turned on, and the fourth switch tube of phase C is turned off, and the first input capacitor charges the first inductor and the first filter capacitor of phase A, the first inductor and the third filter capacitor of phase C;

[0049] In the second period of the switching cycle, the first switch and the third switch are controlled to be closed, the first switch tube of phase A is turned off, the third switch tube of phase A is turned on, the second switch tube of phase C is turned on, and the fourth switch tube of phase C is turned off, and the first filter capacitor and the third filter capacitor continue the current for the first inductor of phase A and the first inductor of phase C.

[0050] In a possible implementation manner, the first control module is further configured to:

[0051] In the third period of the switching cycle, the first switch and the third switch are controlled to be closed, the first switch tube of phase A is turned off, the third switch tube of phase A is turned on, the second switch tube of phase C is turned off, and the fourth switch tube of phase C is turned on, and the second input capacitor charges the first inductor and the first filter capacitor of phase A, the first inductor and the third filter capacitor of phase C;

[0052] In the fourth time period of the switching cycle, the first switch and the third switch are controlled to be closed, the first switch tube of phase A is turned off, the third switch tube of phase A is turned on, the second switch tube of phase C is turned on, and the fourth switch tube of phase C is turned off, and the first filter capacitor and the third filter capacitor continue the current for the first inductor of phase A and the first inductor of phase C.

[0053] In a possible implementation manner, the first control module is further configured to:

[0054] When the duty cycle is greater than the first threshold, in the first period of the switching cycle, the first switch and the third switch are controlled to be closed, the first switch tube of phase A is turned on, the third switch tube of phase A is turned off, the second switch tube of phase C is turned off, and the fourth switch tube of phase C is turned on, and the first input capacitor and the second input capacitor charge the first inductor and the first filter capacitor of phase A, the first inductor and the third filter capacitor of phase C;

[0055] In the second period of the switching cycle, the first switch and the third switch are controlled to be closed, the first switch tube of phase A is turned on, the third switch tube of phase A is turned off, the second switch tube of phase C is turned on, and the fourth switch tube of phase C is turned off, and the first input capacitor, the first filter capacitor, and the third filter capacitor are used to freewheel the first inductor of phase A and the first inductor of phase C.

[0056] In a possible implementation manner, the first control module is further configured to:

[0057] In the third period of the switching cycle, the first switch and the third switch are controlled to be closed, the first switch tube of phase A is turned on, the third switch tube of phase A is turned off, the second switch tube of phase C is turned off, and the fourth switch tube of phase C is turned on, and the first input capacitor and the second input capacitor charge the first inductor and the first filter capacitor of phase A, the first inductor and the third filter capacitor of phase C;

[0058] In the fourth time period of the switching cycle, the first switch and the third switch are controlled to be closed, the first switch tube of phase A is turned off, the third switch tube of phase A is turned on, the second switch tube of phase C is turned off, and the fourth switch tube of phase C is turned on, and the second input capacitor, the first filter capacitor, and the third filter capacitor continue the current for the first inductor of phase A and the first inductor of phase C.

[0059] In a fourth aspect, an embodiment of the present application provides an electronic device, including: a memory, a processor;

[0060] Memory stores computer-executable instructions;

[0061] The processor executes the computer-executable instructions stored in the memory, so that the processor executes the above second aspect and / or various possible implementations of the second aspect.

[0062] In a fifth aspect, an embodiment of the present application provides a computer-readable storage medium, in which computer-executable instructions are stored. When the computer-executable instructions are executed by a processor, they are used to implement the above second aspect and / or various possible implementations of the second aspect.

[0063] In a sixth aspect, an embodiment of the present application provides a computer program product, including a computer program, which, when executed by a processor, implements the above second aspect and / or various possible implementation methods of the second aspect.

[0064] The mobile energy storage vehicle-mounted AC / DC converter and the current conversion control method provided by the embodiment of the present application are that the mobile energy storage vehicle-mounted AC / DC converter adds multiple switches on the basis of the T-type three-level inverter topology structure, thereby smoothing the output voltage waveform or filtering out high-frequency components. At the same time, one end of the multiple switches is respectively connected to the output ends of the A phase, the B phase, and the C phase of the T-type three-level inverter topology structure, and the other end is respectively used as the output end corresponding to the mobile energy storage vehicle-mounted AC / DC converter, so that different voltage types (DC or AC) can be output according to the state of different switches, that is, the first switch and the third switch are closed, and when the second switch is disconnected, the mobile energy storage vehicle-mounted AC / DC converter is output through a DC voltage source in this state, and the output voltage is a constant DC voltage. When the first switch, the second switch, and the third switch are all closed, the output of the AC voltage can be realized through the modulation control of the T-type three-level inverter topology structure, so that different combinations of switches in the mobile energy storage vehicle-mounted AC / DC converter can be achieved. Switching between DC mode and AC mode can meet the different working requirements of the mobile energy storage vehicle, thereby achieving the effect of improving the utilization rate of the conversion equipment and reducing the power loss. BRIEF DESCRIPTION OF THE DRAWINGS

[0065] The accompanying drawings, which are incorporated in and constitute a part of this specification, illustrate embodiments consistent with the present application and, together with the description, serve to explain the principles of the present application.

[0066] Figure 1 A schematic diagram of the circuit structure of a mobile energy storage vehicle-mounted AC / DC converter provided in an embodiment of the present application;

[0067] Figure 2 Schematic diagram of the driving waveform provided in the embodiment of the present application Figure 1 ;

[0068] Figure 3 Schematic diagram of the driving waveform provided in the embodiment of the present application Figure 2 ;

[0069] Figure 4 Schematic diagram of the driving waveform provided in the embodiment of the present application Figure 3 ;

[0070] Figure 5 Schematic diagram of the flow control method provided in the embodiment of the present application Figure 1 ;

[0071] Figure 6 Schematic diagram of the flow control method provided in the embodiment of the present application Figure 2 ;

[0072] Figure 7 Schematic diagram of the current path provided in the embodiment of the present application Figure 1 ;

[0073] Figure 8 Schematic diagram of the current path provided in the embodiment of the present application Figure 2 ;

[0074] Fig. 9 Schematic diagram of the flow control method provided in the embodiment of the present application Figure 3 ;

[0075] Fig.10 Schematic diagram of the current path provided in the embodiment of the present application Figure 3 ;

[0076] Fig.11 Schematic diagram of the current path provided in the embodiment of the present application Figure 4 ;

[0077] Fig.12 Schematic diagram of the current path provided in the embodiment of the present application Figure 5 ;

[0078] Fig.13 Schematic diagram of the flow control method provided in the embodiment of the present application Figure 4 ;

[0079] Fig.14 Schematic diagram of the current path provided in the embodiment of the present application Figure 6 ;

[0080] Fig.15 A schematic diagram of the structure of a variable current control device provided in an embodiment of the present application;

[0081] Fig.16 A schematic diagram of the structure of an electronic device provided in an embodiment of the present application.

[0082] The above drawings have shown clear embodiments of the present application, which will be described in more detail later. These drawings and text descriptions are not intended to limit the scope of the present application in any way, but to illustrate the concept of the present application to those skilled in the art by referring to specific embodiments. DETAILED DESCRIPTION

[0083] Exemplary embodiments will be described in detail herein, examples of which are shown in the accompanying drawings. When the following description refers to the drawings, the same numbers in different drawings represent the same or similar elements unless otherwise indicated. The implementations described in the following exemplary embodiments do not represent all implementations consistent with the present application. Instead, they are merely examples of devices and methods consistent with some aspects of the present application as detailed in the appended claims.

[0084] In addition, the term "first", "second" etc. in the present application is used to distinguish similar objects, and need not be used to describe a specific order or sequential order. It should be understood that the data used in this way can be interchangeable in appropriate circumstances, so that the embodiments of the present application described herein can be implemented in all orders except those illustrated or described here. In addition, the terms "including" and "having" and any of their variations are intended to cover non-exclusive inclusions, for example, the process, method, system, product or equipment comprising a series of steps or units need not be limited to those steps or units clearly listed, but may include other steps or units that are not clearly listed or inherent to these processes, methods, products or equipment.

[0085] First, the terms involved in this application are explained:

[0086] Mobile energy storage vehicle: refers to a vehicle with an integrated energy storage system, usually used for temporary or emergency power supply. It combines battery energy storage technology and vehicle mobility to provide power support in different locations, usually including battery packs, inverters, charging systems, control systems and necessary safety equipment.

[0087] T-type three-level inverter topology: refers to the power electronic topology of a T-type three-level inverter, which is used to convert direct current into alternating current. It mainly includes input capacitors, power switching devices, diodes, etc. Among them, the input capacitor is used to provide a DC power supply and store energy at the input end of the inverter; the power switching device refers to a semiconductor device used to control the on and off of the current, usually an insulated gate bipolar transistor (IGBT) or a metal-oxide-semiconductor field-effect transistor (MOSFET), etc.; the diode is used for current freewheeling and voltage clamping.

[0088] In the prior art, in order to meet different power needs, it is usually necessary to configure DC / AC equipment and DC / DC equipment on the mobile energy storage vehicle. The DC / AC equipment is used to convert direct current (DC) into alternating current (AC) and control the AC voltage and energy, while the DC / DC equipment is used to control the DC voltage and energy to output DC to adapt to different DC loads. However, under normal circumstances, only AC power supply or DC power supply may be required, rather than both at the same time, which means that one of the conversion devices may be idle, adding unnecessary cost and weight, and because of the need to carry infrequently used equipment, the effective use of vehicle space is affected, resulting in reduced transportation efficiency, which in turn leads to increased equipment complexity and energy consumption.

[0089] Based on this, the mobile energy storage vehicle-mounted AC / DC converter and the current conversion control method provided by the present application are based on the consideration of the T-type three-level inverter topology commonly used in DC / AC equipment, and the first switch, the second switch, and the third switch are added to control the three phases of the T-type three-level inverter topology respectively. Therefore, when the first switch and the third switch are both closed and the second switch is disconnected, the T-type three-level inverter can output through the DC voltage source in this state, at which time the A phase is equivalent to the positive pole of the DC output, the C phase is equivalent to the negative pole of the DC output, and the B phase is not output, and the output voltage is a constant DC voltage; and when the first switch, the second switch and the third switch are all closed, the A phase, the B phase, and the C phase are the three-phase output terminals of the inverter, and the T-type three-level inverter works normally, converting the DC voltage into three-phase AC power and outputting it. Thereby, the mobile energy storage vehicle can flexibly provide DC or AC power when needed, adapt to different power requirements, avoid unnecessary equipment idleness, and make better use of the capacity of the energy storage battery.

[0090] The technical solution of the present application and how the technical solution of the present application solves the above-mentioned technical problems are described in detail below with specific embodiments. The following specific embodiments can be combined with each other, and the same or similar concepts or processes may not be repeated in some embodiments. The embodiments of the present application will be described below in conjunction with the accompanying drawings.

[0091] Figure 1 This is a schematic diagram of the circuit structure of the mobile energy storage vehicle-mounted AC / DC converter provided in the embodiment of the present application. Figure 1 As shown, the AC-DC converter includes: a T-type three-level inverter topology structure, a first switch, a second switch and a third switch;

[0092] One end of the first switch is connected to the A-phase output end of the T-type three-level inverter topology structure, and the other end of the first switch serves as the A-phase output end of the mobile energy storage vehicle-mounted AC / DC converter;

[0093] One end of the second switch is connected to the B-phase output end of the T-type three-level inverter topology structure, and the other end of the second switch serves as the B-phase output end of the mobile energy storage vehicle-mounted AC / DC converter;

[0094] One end of the third switch is connected to the C-phase output end of the T-type three-level inverter topology structure, and the other end of the third switch serves as the C-phase output end of the mobile energy storage vehicle-mounted AC / DC converter;

[0095] When the first switch and the third switch are both closed and the second switch is open, the mobile energy storage vehicle-mounted AC / DC converter outputs a DC voltage; when the first switch, the second switch and the third switch are all closed, the mobile energy storage vehicle-mounted AC / DC converter outputs an AC voltage.

[0096] In this embodiment, the T-type three-level inverter has three level outputs: positive level, zero level and negative level. These levels are switched by multiple switching tubes, and through an appropriate pulse width modulation (PWM) control strategy, a three-phase AC voltage or DC voltage can be generated at the output end of the inverter.

[0097] In the case of DC voltage output, two switches (first switch S1, third switch S3) control the output of phase A and phase C respectively. In the operation of the T-type three-level inverter, if the switches of phase A and phase C (i.e., the first switch S1 and the third switch S3) are closed, and the switch of phase B (i.e., the second switch S2) is open, then the output of phase A and phase C will determine the output voltage. At this time, the output voltage of the inverter mainly comes from the voltage regulation of phase A and phase C, and since no alternating voltage is generated (phase B does not participate in the operation), the duty cycle of phase A and phase C is adjusted through PWM to control the output DC voltage.

[0098] In the case of AC voltage output, when all switches (first switch, second switch and third switch) are closed, the switch tubes of phase A, phase B and phase C are all involved in the work, and the output of the inverter will generate AC voltage according to the control signals of these three phases. At this time, the voltage waveform and duty cycle of each phase are adjusted through the corresponding PWM control to ensure that there is a 120-degree phase difference between them, thereby controlling the output AC voltage.

[0099] It should be noted that the input of the AC-DC converter is the DC voltage V_dc provided by the battery. The battery is connected to the positive and negative busbars of the T-type three-level inverter through input capacitors C1 and C2. The battery voltage is distributed on these two input capacitors, and the voltage of each capacitor is 0.5V_dc. The output voltage Uo is determined by the voltage difference between the filter capacitors C_A and C_C, that is, Uo = U C_A -U C_C .

[0100] Each phase bridge arm is connected to the positive electrode, negative electrode and midpoint of the three-level battery. Specifically, the A-phase bridge arm includes four switching tubes T1_A, T2_A, T3_A, and T4_A, and D1_A, D2_A, D3_A, and D4_A are respectively the anti-parallel diodes of the A-phase switching tube; the B-phase bridge arm includes four switching tubes T1_B, T2_B, T3_B, and T4_B, and D1_B, D2_B, D3_B, and D4_B are respectively the anti-parallel diodes of the B-phase switching tube; the C-phase bridge arm includes four switching tubes T1_C, T2_C, T3_C, and T4_C, and D1_C, D2_C, D3_C, and D4_C are respectively the anti-parallel diodes of the C-phase switching tube.

[0101] For each phase bridge arm, the first switch tube and the fourth switch tube are connected in series to the positive and negative electrodes of the battery, and the second switch tube and the third switch tube are connected in series, one end is connected to the midpoint of the three-level, and the other end is connected to the connection point of the first switch tube and the fourth switch tube. At the same time, the second switch tube and the third switch tube are connected in series with the first inductor L1 and the second inductor L2 respectively, and are controlled by the corresponding switches (S1, S2, S3). A filter capacitor is also provided on each phase bridge arm, one end of the filter capacitor is connected to the midpoint of the three-level, and the other end is connected to the connection point of the first inductor L1 and the second inductor L2.

[0102] It is understandable that the T-type three-level inverter topology itself is a common structure in a multi-level inverter, and its advantage is that it provides a smoother output voltage than a traditional two-level inverter, reducing harmonics and switching losses. However, the embodiment of the present application adds multiple switches on the basis of the original three-level inverter, connects one end of the multiple switches to the output end of phase A, phase B, and phase C, and connects the other end to the output end of the mobile energy storage vehicle-mounted AC / DC converter. According to the state of different switches, the output voltage type can be switched (such as DC or AC voltage), further enhancing the flexibility and accuracy of voltage regulation, and improving the output voltage type or adjustment range of the system, so that the topology can adapt to a wider range of application requirements in the mobile energy storage system. At the same time, this flexible control method allows the system to dynamically adjust the output type according to demand, thereby meeting different load requirements and operating modes, without the need to install independent DC / AC and DC / DC conversion equipment at the same time, thereby saving space and cost.

[0103] In an achievable manner, the AC-DC converter further includes: a fourth switch, one end of the fourth switch being connected to the midpoint of the filter capacitor of the T-type three-level inverter topology structure, and the other end of the fourth switch being connected to the midpoint of the three levels of the T-type three-level inverter topology structure;

[0104] When the fourth switch is closed, the fourth switch tube of phase A is turned off, the second switch tube is turned on, the first switch tube and the third switch tube are driven complementarily, and the first switch tube of phase C is turned off, the third switch tube is turned on, and the fourth switch tube and the second switch tube are driven complementarily;

[0105] When the fourth switch is disconnected, the fourth switch tube of phase A is turned off, the second switch tube is turned on, and the first switch tube and the third switch tube are driven complementarily, and the first switch tube of phase C is turned off, the third switch tube is turned on, and the fourth switch tube and the second switch tube are driven complementarily, and the first switch tube of phase A and the fourth switch tube of phase C are driven alternately.

[0106] The midpoint of the filter capacitor of the T-type three-level inverter topology structure refers to the potential center of the DC power supply side, that is, the midpoint of the DC bus voltage, and the three-level midpoint of the T-type three-level inverter topology structure refers to the balance point between the high voltage and the low voltage.

[0107] When the fourth switch S4 is closed, the fourth switch tube T4_A of the A phase is closed, the second switch tube T2_A is turned on, and the first switch tube T1_A and the third switch tube T3_A are driven complementarily, indicating that the A phase can provide current to the load through the second switch tube T2_A, and the first switch tube T1_A and the third switch tube T3_A complement each other (that is, one is turned on and the other is turned off) to ensure the correct voltage output; similarly, the first switch tube T1_C of the C phase is closed, the third switch tube T3_C is turned on, and the fourth switch tube T4_C and the second switch tube T2_C are driven complementarily, indicating that the C phase is connected to the load through the third switch tube T3_C to realize the flow of current, and the fourth switch tube T4_C and the second switch tube T2_C are controlled complementarily to ensure smooth conversion of the output voltage. Therefore, when the fourth switch S4 is closed, the switch tubes of the A phase and the C phase work together through a series of complementary drives to achieve the required voltage waveform.

[0108] like Figure 2 As shown, Figure 2 Schematic diagram of the driving waveform provided in the embodiment of the present application Figure 1. In one switching cycle, T4_A is turned off, T2_A is turned on; T1_C is turned off, T3_C is turned on; the four switch tubes of the B phase bridge arm are all turned off. In the t0-t1 period, the first switch tube T1_A of the A phase is turned on, the third switch tube T3_A of the A phase is turned off, the fourth switch tube T4_C of the C phase is turned on, and the second switch tube T2_C of the C phase is turned off; in the t1-t2 period, the first switch tube T1_A of the A phase is turned off, the third switch tube T3_A of the A phase is turned on, the fourth switch tube T4_C of the C phase is turned off, and the second switch tube T2_C of the C phase is turned on.

[0109] In this embodiment, the switching behavior of each switch tube is controlled by PWM technology, that is, under PWM control, the switching states of T1_A and T3_A, T4_C and T2_C are all controlled by PWM signals.

[0110] Specifically, the PWM signal is generated by comparing a triangular wave or carrier signal with a reference signal (usually a sine wave, triangular wave, etc.). The frequency of the reference signal determines the frequency of the output voltage, and the frequency of the carrier signal determines the switching frequency of the PWM. By adjusting the duty cycle of the PWM (i.e., the ratio of the on time to the off time in the switching cycle), the switching time of T1_A and T3_A, T4_C and T2_C can be adjusted, and the change of the duty cycle will affect the amplitude of the output voltage.

[0111] Exemplarily, when AC output is used, three sine waves can be used for modulation of phase A, phase B, and phase C, and the three sine waves differ in phase by 120 degrees. When DC output is used, all drivers of phase B are turned off, the fourth switch tube T4_A of phase A is turned off, and the second switch tube T2_A is turned on; the first switch tube T1_C of phase C is turned off, and the third switch tube T3_C is turned on. The first switch tube T1_A of phase A and the fourth switch tube T4_C of phase C use a stable DC for modulation, so that the switching states of T1_A and T3_A, T4_C and T2_C are continuously switched throughout the cycle to generate an average voltage (DC voltage). The accuracy of PWM control allows the output voltage waveform to be close to the ideal DC, thereby improving the efficiency and performance of the converter.

[0112] When the fourth switch S4 is disconnected, its driving mode is the same as the above embodiment, except that the first switch tube T1_A of phase A and the fourth switch tube T4_C of phase C are driven alternately with a phase difference of 180 degrees, that is, the two switch tubes are driven staggered in timing, thereby optimizing the output waveform and reducing harmonics.

[0113] like Figure 3 As shown, Figure 3 Schematic diagram of the driving waveform provided in the embodiment of the present application Figure 2. In one switching cycle, T4_A is off, T2_A is on; T1_C is off, T3_C is on; all four switch tubes of the B phase bridge arm are off. In the t0-t1 period, T1_A of phase A is on, T3_A is off, T4_C of phase C is off, and T2_C is on; in the t1-t2 period, T1_A of phase A is off, T3_A is on, T4_C of phase C is off, and T2_C is on; in the t2-t3 period, T1_A of phase A is off, T3_A is on, T4_C of phase C is on, and T2_C is off; in the t3-t4 period, T1_A of phase A is off, T3_A is on, T4_C of phase C is off, and T2_C is on.

[0114] In this embodiment, the duty cycle is less than a first threshold value, and the first threshold value may be 0.5.

[0115] Similar to the above embodiment, in this embodiment, the switching behavior of each switch tube is controlled by PWM technology, that is, under PWM control, the switching states of T1_A and T3_A, T4_C and T2_C are all controlled by PWM signals, which will not be described in detail in this embodiment.

[0116] like Figure 4 As shown, Figure 4 Schematic diagram of the driving waveform provided in the embodiment of the present application Figure 3 . In one switching cycle, T4_A is turned off, T2_A is turned on; T1_C is turned off, T3_C is turned on; the four switch tubes of the bridge arm of phase B are all turned off. In the period t0-t1, T1_A of phase A is turned on, T3_A is turned off, T4_C of phase C is turned on, and T2_C is turned off; in the period t1-t2, T1_A of phase A is turned on, T3_A is turned off, T4_C of phase C is turned off, and T2_C is turned on; in the period t2-t3, T1_A of phase A is turned on, T3_A is turned off, T4_C of phase C is turned on, and T2_C is turned off; in the period t3-t4, T1_A of phase A is turned off, T3_A is turned on, T4_C of phase C is turned on, and T2_C is turned off.

[0117] In this embodiment, the duty cycle is greater than a first threshold value, and the first threshold value may be 0.5.

[0118] Similar to the above embodiment, in this embodiment, the switching behavior of each switch tube is controlled by PWM technology, and this embodiment will not be described in detail here.

[0119] It can be understood that the closed and open states of the fourth switch S4 control the working states of different switches, affecting the driving strategy of the switches of each phase (phase A and phase C) of the T-type three-level inverter, and can provide additional circuit paths and voltage balance options, and change the current path and voltage output characteristics of the circuit. Through staggered driving, the working cycles of the switch tubes of phase A and phase C are staggered, which helps to reduce harmonic components and thus improve the quality of the output waveform.

[0120] In one achievable manner, the three-level of the T-type three-level inverter topology structure adopts a filter output, and the filter capacitor in the filter adopts a non-polarized capacitor.

[0121] In this embodiment, the filter can be an LC filter or an LCL filter. The LC filter refers to a filter composed of an inductor (L) and a capacitor (C), which is used to smooth the voltage waveform and reduce high-frequency harmonics and noise. The LCL filter adds an additional inductor to the LC filter to improve the filtering effect and can provide better high-frequency harmonic suppression capabilities.

[0122] Among them, non-polar capacitors are capacitors without polarity restrictions and can be connected in any direction in the circuit, including ceramic capacitors, film capacitors and some electrolytic capacitors. They are suitable for filtering applications of AC signals and will not be damaged by reverse polarity.

[0123] It can be understood that, by using non-polarized capacitors, voltage inversion in the AC signal can be processed, which enables the filter circuit to smooth the AC output waveform when outputting the AC voltage.

[0124] The mobile energy storage vehicle-mounted AC-DC converter provided in the embodiment of the present application controls the output of phase A, phase B and phase C respectively through the first switch, the second switch and the third switch. When the first switch and the third switch are closed and the second switch is disconnected, phase A serves as the DC output positive pole and phase C serves as the DC output negative pole, and a DC voltage can be output. When the first switch, the second switch and the third switch are all closed, the switch tubes of phase A, phase B and phase C are all involved in the work, and the output of the inverter will generate an AC voltage according to the control signals of these three phases, thereby outputting an AC voltage. Therefore, the mobile energy storage vehicle-mounted AC-DC converter has little modification to the existing equipment, can meet the output AC or DC requirements at the same time, has strong adaptability, thereby improving the utilization rate of the converter equipment and increasing the emergency power supply time.

[0125] Figure 5 Schematic diagram of the flow control method provided in the embodiment of the present application Figure 1 .like Figure 5 As shown, the method is used to control the mobile energy storage vehicle-mounted AC / DC converter of any of the above embodiments, and the method includes:

[0126] S101. Obtain voltage output requirements, where the voltage output requirements include direct current voltage output and alternating current voltage output.

[0127] The execution subject of the embodiment of the present application is an electronic device, which may be a terminal device, such as a vehicle-mounted computer or a vehicle-mounted control system, etc. In practical applications, the electronic device may be determined according to actual conditions, and this embodiment does not impose any specific restrictions on this.

[0128] Among them, voltage output demand refers to the specific requirements of the vehicle system or user for voltage output, including parameters such as voltage type (DC or AC), voltage amplitude, and frequency (for AC).

[0129] For example, the user can select the required voltage output type through the vehicle interface or mobile application. For example, the user may need to select DC or AC output to power external devices; the voltage output requirement can also be determined by detecting the type of device connected to the vehicle power socket. For example, the vehicle's intelligent system can identify the type of power required for the plugged-in device; or the status of the electrical system can be monitored through sensors equipped in the vehicle. For example, the battery management system (BMS) can detect the voltage and charge status of the battery, and decide whether the voltage output needs to be adjusted to optimize battery performance based on this data.

[0130] It should be noted that DC voltage output refers to the output in the form of a current with a constant voltage, which is usually used to power DC loads, such as battery charging, DC motor driving, etc. AC voltage output refers to the output in the form of a voltage that changes periodically, which is usually used to power AC loads, such as electrical appliances, AC motors, etc.

[0131] S102: If the voltage output requirement is a DC voltage output, control the first switch and the third switch to be closed, and control the second switch to be open.

[0132] In this embodiment, the first switch S1 and the third switch S2 are in the on state, allowing current to pass through these switches to form a specific current path to achieve the output of a DC voltage. At the same time, the second switch S2 is in the off state, preventing current from passing through, ensuring the correctness of the current path to achieve the desired DC voltage output.

[0133] S103: If the voltage output requirement is an AC voltage output, control the first switch, the second switch, and the third switch to be closed.

[0134] In this embodiment, the three switches are in the on state, allowing current to pass through the switches, and the T-type three-level inverter can generate a voltage signal close to a sine waveform through a pulse width modulation technology, that is, a three-phase alternating current output.

[0135] The current conversion control method provided in the embodiment of the present application uses a T-type three-level inverter and accurately controls the closing state of the switch on this basis. It can effectively configure the circuit to achieve the required voltage output, and can dynamically adjust the output mode according to real-time needs, thereby reducing unnecessary energy loss and improving overall efficiency.

[0136] Figure 6 Schematic diagram of the flow control method provided in the embodiment of the present application Figure 2 .like Figure 6 As shown, this embodiment is Figure 5 Based on the embodiment, the process of S102 is described in detail, which specifically includes the following steps:

[0137] S201. If the fourth switch is controlled to be closed, in the first period of the switching cycle, the first switch is controlled to be closed, the first switch tube of phase A is turned on, and the third switch tube of phase A is turned off, and the first input capacitor of the T-type three-level inverter topology structure charges the first inductor and the first filter capacitor of phase A.

[0138] Among them, the switching cycle refers to the time that the switching element experiences in a complete on and off cycle. A switching cycle is divided into multiple time periods, which are used to implement different circuit operations. The first time period is the t0-t1 period, and the second time period is the t1-t2 period, which respectively represent the steady-state operation process of the circuit under different states of the switch tube. In each time period, the voltage will continue to change according to a certain law or cycle.

[0139] The switch tube may refer to a switching element used to control the flow of current, usually a transistor (such as IGBT, MOSFET, etc.). In this embodiment, the switch tube controls the conduction and shutdown of the current through a switching operation, thereby regulating the flow and conversion of electric energy.

[0140] The first input capacitor C1 and the second input capacitor C2 are used to store electric energy and provide smooth voltage input. In the inverter system of this embodiment, the first input capacitor C1 and the second input capacitor C2 are used for filtering, thereby reducing the impact of voltage fluctuations on system stability and reducing power supply interference.

[0141] The first inductor L1_A of phase A and the first inductor L1_C of phase C are used for energy storage, filtering and regulating the stability of current. In the inverter system of this embodiment, the inductor helps to smooth the current waveform and reduce the sudden change of current during the switching process.

[0142] The first filter capacitor C_A and the third filter capacitor C_C are used to smooth the output voltage and reduce high-frequency noise or harmonics in the voltage or current. In the inverter system of this embodiment, the filter capacitor is connected to the load side to help smooth the pulsating output current into a more stable waveform.

[0143] like Figure 7 As shown, Figure 7 Schematic diagram of the current path provided in the embodiment of the present application Figure 1 . Wherein, R is the load. In this embodiment, during the period t0-t1, the current path is as shown by the solid arrow, and the voltage (0.5*V_dc) on the first input capacitor C1 passes through the first switch tube T1_A of the A-phase bridge arm to provide electrical energy to the first inductor L1_A and the first filter capacitor C_A for charging.

[0144] S202, control the third switch to close, the second switch tube of phase C to turn off, the fourth switch tube of phase C to turn on, and the second input capacitor of the T-type three-level inverter topology structure charges the first inductor and the third filter capacitor of phase C.

[0145] like Figure 7 As shown, in this embodiment, the current path is shown by the dotted arrow, and the voltage (0.5*V_dc) on the second output capacitor C2 passes through the fourth switch tube T4_C of the C-phase bridge arm to provide electrical energy to the third filter capacitor C_C and the first inductor L1_C of the C-phase bridge arm for charging.

[0146] S203 . In the second period of the switching cycle, the first switch is controlled to be closed, the first switch tube of the A phase is turned off, the third switch tube of the A phase is turned on, and the first filter capacitor freewheels the first inductor of the A phase.

[0147] In this embodiment, the current in the inductor continues to flow through other paths at this time, preventing the current of the inductor from being interrupted and maintaining the continuity of the current.

[0148] like Figure 8 As shown, Figure 8 Schematic diagram of the current path provided in the embodiment of the present application Figure 2 In this embodiment, during the period t1-t2, the current path is as indicated by the solid arrow, and the first inductor L1_A of the A-phase bridge arm continues current under the voltage of the first filter capacitor C_A.

[0149] S204, controlling the third switch to close, the second switch tube of the C phase to turn on, the fourth switch tube of the C phase to turn off, and the third filter capacitor to freewheel the first inductor of the C phase.

[0150] like Figure 8 As shown, in this embodiment, the current path is shown by the dotted arrow, and the first inductor L1_C of the C-phase bridge arm continues current under the voltage of the third filter capacitor C_C.

[0151] It can be understood that the freewheeling effect of the filter capacitor makes the current smoother, reduces the impact on the current during the switching process, and thus improves the stability of the entire power system.

[0152] It should be noted that when the output voltage of phase A and phase C is adjusted correctly, the output voltage can be controlled by the duty cycle, and since phase B is not turned on, the overall output is a DC voltage. At this time, the output voltage Uo=0.5*Uin*(D T1_A +D T4_C ), when the duty cycle satisfies D T1_A =D T4_C =D, according to the volt-second balance across the inductor, we can get Uo=Uin*D, where Uo is the output voltage; Uin is the input voltage; D T1_A is the duty cycle of the first switch tube of phase A, D T4_C is the duty cycle of the fourth switch tube of phase C.

[0153] The current conversion control method provided in the embodiment of the present application can control the duty cycle of the first switch tube of the A phase and the duty cycle of the fourth switch tube of the C phase bridge arm by controlling the switch tubes of the A phase bridge arm and the C phase bridge arm and coordinating the filter capacitor and the inductor. When the first switch, the third switch, and the fourth switch are closed and the third switch is disconnected, the output DC voltage can be controlled by controlling the duty cycle of the first switch tube of the A phase and the duty cycle of the fourth switch tube, thereby achieving smoothing of the current waveform and effective conversion of energy.

[0154] Fig. 9 Schematic diagram of the flow control method provided in the embodiment of the present application Figure 3 .like Fig. 9 As shown, this embodiment is Figure 5 Based on the embodiment, the process of S102 is described in detail, which specifically includes the following steps:

[0155] S301. If the fourth switch is controlled to be disconnected, when the duty cycle is less than the first threshold value, in the first time period of the switching cycle, the first switch and the third switch are controlled to be closed, the first switch tube of phase A is turned on, the third switch tube of phase A is turned off, the second switch tube of phase C is turned on, and the fourth switch tube of phase C is turned off, and the first input capacitor charges the first inductor, the first filter capacitor of phase A, the first inductor, and the third filter capacitor of phase C.

[0156] In this embodiment, T4_A is turned off, T2_A is turned on; T1_C is turned off, T3_C is turned on; and the four switch tubes of the B-phase bridge arm are all turned off.

[0157] In this embodiment, the fourth switch is disconnected, and the midpoint of the filter capacitor of the T-type three-level inverter topology structure is not connected to the midpoint of the three levels. There is no neutral line in the circuit structure. The current flows from the first input capacitor to the A-phase inductor and its filter capacitor, and the C-phase inductor and its filter capacitor, thereby completing the charging of the A-phase and C-phase parts, that is, the first input capacitor provides energy to the inductor and filter capacitor of the A-phase, and provides energy to the inductor and filter capacitor of the C-phase.

[0158] like Fig.10 As shown, Fig.10 Schematic diagram of the current path provided in the embodiment of the present application Figure 3 In this embodiment, during the period t0-t1, the current path is shown by the solid arrow, and the voltage (0.5*V_dc) on the first input capacitor C1 charges the A-phase first inductor L1_A, the C-phase first inductor L1_C, the first capacitor C_A, and the third capacitor C_C through T1_A and T2_C.

[0159] It can be understood that by controlling the first input capacitor to charge the inductor and the filter capacitor in the first period, the system can effectively manage and store energy so as to release it in the subsequent period.

[0160] S302. In the second period of the switching cycle, the first switch and the third switch are controlled to be closed, the first switch tube of phase A is closed, the third switch tube of phase A is turned on, the second switch tube of phase C is turned on, and the fourth switch tube of phase C is closed, and the first filter capacitor and the third filter capacitor are used to freewheel the first inductor of phase A and the first inductor of phase C.

[0161] In this embodiment, the state of each switch (S1, S2, S3, S4) remains unchanged, but the state of the switch tube is switched. By turning the switch tube on and off, the freewheeling action between the filter capacitor and the inductor begins, thereby maintaining a smooth flow of current, avoiding instantaneous current fluctuations, and ensuring the stability of the system.

[0162] like Fig.11 As shown, Fig.11 Schematic diagram of the current path provided in the embodiment of the present application Figure 4 In this embodiment, during the period t1-t2, the current path is as indicated by the solid arrows, and the first inductor L1_A of the A phase and the first inductor L1_C of the C phase continue to flow under the voltage of the first capacitor C_A and the third capacitor C_C.

[0163] S303. In the third time period of the switching cycle, the first switch and the third switch are controlled to be closed, the first switch tube of phase A is turned off, the third switch tube of phase A is turned on, the second switch tube of phase C is turned off, and the fourth switch tube of phase C is turned on, and the second input capacitor charges the first inductor and the first filter capacitor of phase A, the first inductor and the third filter capacitor of phase C.

[0164] In this embodiment, the second input capacitor starts to charge the A-phase inductor and the filter capacitor, and this process continues to provide electrical energy to the A-phase inductor to ensure a stable voltage waveform of the system.

[0165] like Fig.12 As shown, Fig.12 Schematic diagram of the current path provided in the embodiment of the present application Figure 5In this embodiment, during the period t2-t3, the current path is shown by the solid arrow, and the voltage (0.5*V_dc) on the capacitor C2 charges the first inductor L1_A of the A phase, the first inductor L1_C of the C phase, the first capacitor C_A, and the third capacitor C_C through T4_C and T3_A.

[0166] S304. In the fourth time period of the switching cycle, the first switch and the third switch are controlled to be closed, the first switch tube of phase A is turned off, the third switch tube of phase A is turned on, the second switch tube of phase C is turned on, and the fourth switch tube of phase C is turned off, and the first filter capacitor and the third filter capacitor are used to freewheel the first inductor of phase A and the first inductor of phase C.

[0167] In this embodiment, the current path is as follows Fig.11 As shown, the current path during the period t3 - t4 is the same as that during the period t1 - t2 , and this embodiment will not be described in detail here.

[0168] It should be noted that when the output voltage of phase A and phase C is adjusted correctly, the output voltage can also be controlled by the duty cycle. C_A -U C_C , when the duty cycle satisfies D T1_A =D T4_C When =D, according to the volt-second balance across the inductor, we can get Uo=Uin*D.

[0169] The current conversion control method provided in the embodiment of the present application ensures efficient and stable operation of the power system by accurately controlling the switching behavior and the charging and discharging process of capacitors and inductors in each time period. In this way, energy can be smoothly and effectively transferred between different phases and circuit components, thereby reducing high-frequency noise, improving the output voltage quality, and ultimately achieving efficient and stable DC output.

[0170] Fig.13 Schematic diagram of the flow control method provided in the embodiment of the present application Figure 4 .like Fig.13 As shown, this embodiment is Figure 5 Based on the embodiment, the process of S102 is described in detail, which specifically includes the following steps:

[0171] S401. When the duty cycle is greater than the first threshold, in the first time period of the switching cycle, the first switch and the third switch are controlled to be closed, the first switch tube of phase A is turned on, the third switch tube of phase A is turned off, the second switch tube of phase C is turned off, and the fourth switch tube of phase C is turned on, and the first input capacitor and the second input capacitor charge the first inductor, the first filter capacitor of phase A, the first inductor, and the third filter capacitor of phase C.

[0172] like Fig.14 As shown, Fig.14Schematic diagram of the current path provided in the embodiment of the present application Figure 6 Wherein, R is the load. In this embodiment, during the period t0-t1, the current path is shown by the solid arrow, and the voltage (V_dc) after the input capacitors C1 and C2 are connected in series charges the inductors L1_A, L1_C and the capacitors C_A, C_C through T1_A and T4_C.

[0173] S402. In the second period of the switching cycle, the first switch and the third switch are controlled to be closed, the first switch tube of phase A is turned on, the third switch tube of phase A is turned off, the second switch tube of phase C is turned on, and the fourth switch tube of phase C is turned off, and the first input capacitor, the first filter capacitor, and the third filter capacitor are used to freewheel the first inductor of phase A and the first inductor of phase C.

[0174] In this embodiment, the current path is as follows Fig.10 As shown, when the duty cycle is greater than the first threshold value 0.5, the current path in the period t1-t2 is the same as that in the period t0-t1 when the duty cycle is less than the first threshold value 0.5, and this embodiment will not be repeated here.

[0175] S403. In the third time period of the switching cycle, the first switch and the third switch are controlled to be closed, the first switch tube of phase A is turned on, the third switch tube of phase A is turned off, the second switch tube of phase C is turned off, and the fourth switch tube of phase C is turned on, and the first input capacitor and the second input capacitor charge the first inductor, the first filter capacitor of phase A, the first inductor, and the third filter capacitor of phase C.

[0176] In this embodiment, the current path is as follows Fig.14 As shown, when the duty cycle is greater than the first threshold value 0.5, the current path in the period t2-t3 is the same as that in the period t0-t1, and this embodiment will not be described in detail here.

[0177] S404. In the fourth time period of the switching cycle, the first switch and the third switch are controlled to be closed, the first switch tube of phase A is turned off, the third switch tube of phase A is turned on, the second switch tube of phase C is turned off, and the fourth switch tube of phase C is turned on, and the second input capacitor, the first filter capacitor, and the third filter capacitor are used to freewheel the first inductor of phase A and the first inductor of phase C.

[0178] In this embodiment, the current path is as follows Fig.12 As shown, when the duty cycle is greater than the first threshold value 0.5, the current path in the period t3-t4 is the same as that in the period t2-t3 when the duty cycle is less than the first threshold value 0.5, and this embodiment will not be repeated here.

[0179] The current conversion control method provided in the embodiment of the present application can effectively adjust the voltage waveform by controlling the conduction and disconnection of different switching elements in different time periods. By using multiple time periods to charge and discharge the inductor and filter capacitor, the high-frequency harmonic components in the output waveform can be reduced, and the peaks or fluctuations of the output voltage and current can be reduced, ultimately providing a smoother output and achieving efficient energy transmission.

[0180] Fig.15 This is a schematic diagram of the structure of the variable current control device provided in the embodiment of the present application. Fig.15 As shown, the variable current control device 50 includes:

[0181] An acquisition module 501 is used to acquire a voltage output requirement, where the voltage output requirement includes a DC voltage output and an AC voltage output;

[0182] The first control module 502 is used to control the first switch and the third switch to be closed and the second switch to be opened if the voltage output requirement is a DC voltage output;

[0183] The second control module 503 is used to control the first switch, the second switch and the third switch to be closed if the voltage output requirement is an AC voltage output.

[0184] In a possible implementation, the first control module 502 is specifically configured to:

[0185] If the fourth switch is controlled to be closed, in the first period of the switching cycle, the first switch is controlled to be closed, the first switch tube of phase A is turned on, the third switch tube of phase A is turned off, and the first input capacitor of the T-type three-level inverter topology structure charges the first inductor and the first filter capacitor of phase A;

[0186] The third switch is controlled to be closed, the second switch tube of phase C is turned off, the fourth switch tube of phase C is turned on, and the second input capacitor of the T-type three-level inverter topology structure charges the first inductor and the third filter capacitor of phase C.

[0187] In a possible implementation manner, the first control module 502 is further configured to:

[0188] In the second period of the switching cycle, the first switch is controlled to be closed, the first switch tube of phase A is turned off, the third switch tube of phase A is turned on, and the first filter capacitor freewheels the first inductor of phase A;

[0189] The third switch is controlled to be closed, the second switch tube of the C phase is turned on, the fourth switch tube of the C phase is turned off, and the third filter capacitor continues the current flow of the first inductor of the C phase.

[0190] In a possible implementation manner, the first control module 502 is further configured to:

[0191] If the fourth switch is controlled to be disconnected, when the duty cycle is less than the first threshold, in the first period of the switching cycle, the first switch and the third switch are controlled to be closed, the first switch tube of phase A is turned on, the third switch tube of phase A is turned off, the second switch tube of phase C is turned on, and the fourth switch tube of phase C is turned off, and the first input capacitor charges the first inductor and the first filter capacitor of phase A, the first inductor and the third filter capacitor of phase C;

[0192] In the second period of the switching cycle, the first switch and the third switch are controlled to be closed, the first switch tube of phase A is turned off, the third switch tube of phase A is turned on, the second switch tube of phase C is turned on, and the fourth switch tube of phase C is turned off, and the first filter capacitor and the third filter capacitor continue the current for the first inductor of phase A and the first inductor of phase C.

[0193] In a possible implementation manner, the first control module 502 is further configured to:

[0194] In the third period of the switching cycle, the first switch and the third switch are controlled to be closed, the first switch tube of phase A is turned off, the third switch tube of phase A is turned on, the second switch tube of phase C is turned off, and the fourth switch tube of phase C is turned on, and the second input capacitor charges the first inductor and the first filter capacitor of phase A, the first inductor and the third filter capacitor of phase C;

[0195] In the fourth time period of the switching cycle, the first switch and the third switch are controlled to be closed, the first switch tube of phase A is turned off, the third switch tube of phase A is turned on, the second switch tube of phase C is turned on, and the fourth switch tube of phase C is turned off, and the first filter capacitor and the third filter capacitor continue the current for the first inductor of phase A and the first inductor of phase C.

[0196] In a possible implementation manner, the first control module 502 is further configured to:

[0197] When the duty cycle is greater than the first threshold, in the first period of the switching cycle, the first switch and the third switch are controlled to be closed, the first switch tube of phase A is turned on, the third switch tube of phase A is turned off, the second switch tube of phase C is turned off, and the fourth switch tube of phase C is turned on, and the first input capacitor and the second input capacitor charge the first inductor and the first filter capacitor of phase A, the first inductor and the third filter capacitor of phase C;

[0198] In the second period of the switching cycle, the first switch and the third switch are controlled to be closed, the first switch tube of phase A is turned on, the third switch tube of phase A is turned off, the second switch tube of phase C is turned on, and the fourth switch tube of phase C is turned off, and the first input capacitor, the first filter capacitor, and the third filter capacitor are used to freewheel the first inductor of phase A and the first inductor of phase C.

[0199] In a possible implementation manner, the first control module 502 is further configured to:

[0200] In the third period of the switching cycle, the first switch and the third switch are controlled to be closed, the first switch tube of phase A is turned on, the third switch tube of phase A is turned off, the second switch tube of phase C is turned off, and the fourth switch tube of phase C is turned on, and the first input capacitor and the second input capacitor charge the first inductor and the first filter capacitor of phase A, the first inductor and the third filter capacitor of phase C;

[0201] In the fourth time period of the switching cycle, the first switch and the third switch are controlled to be closed, the first switch tube of phase A is turned off, the third switch tube of phase A is turned on, the second switch tube of phase C is turned off, and the fourth switch tube of phase C is turned on, and the second input capacitor, the first filter capacitor, and the third filter capacitor continue the current for the first inductor of phase A and the first inductor of phase C.

[0202] The current conversion control device provided in this embodiment can execute the method provided in the above method embodiment. Its implementation principle and technical effect are similar, and this embodiment will not be described in detail here.

[0203] Fig.16 This is a schematic diagram of the structure of an electronic device provided in an embodiment of the present application. Fig.16 As shown, the electronic device 60 provided in this embodiment includes: at least one processor 601 and a memory 602. Optionally, the device 60 also includes a communication component 603. The processor 601, the memory 602 and the communication component 603 are connected via a bus 604.

[0204] In a specific implementation process, at least one processor 601 executes the computer execution instructions stored in the memory 602, so that at least one processor 601 executes the above method.

[0205] The specific implementation process of the processor 601 can be found in the above method embodiment, and its implementation principle and technical effect are similar, so this embodiment will not be repeated here.

[0206] In the above embodiments, it should be understood that the processor may be a central processing unit (CPU), or other general-purpose processors, digital signal processors (DSP), application-specific integrated circuits (ASIC), etc. A general-purpose processor may be a microprocessor or any conventional processor. The steps of the method disclosed in the invention may be directly implemented as being executed by a hardware processor, or may be executed by a combination of hardware and software modules in the processor.

[0207] The memory may include a high-speed memory (Random Access Memory, RAM), and may also include a non-volatile memory (Non-volatile Memory, NVM), such as at least one disk memory.

[0208] The bus may be an Industry Standard Architecture (ISA) bus, a Peripheral Component Interconnect (PCI) bus, or an Extended Industry Standard Architecture (EISA) bus, etc. The bus may be divided into an address bus, a data bus, a control bus, etc. For ease of representation, the bus in the drawings of the present application is not limited to only one bus or one type of bus.

[0209] The present application also provides a computer program product, including a computer program, which implements the above method when executed by a processor.

[0210] The present application also provides a computer-readable storage medium, in which computer-executable instructions are stored. When a processor executes the computer-executable instructions, the above method is implemented.

[0211] The above-mentioned readable storage medium can be implemented by any type of volatile or non-volatile storage device or a combination thereof, such as static random access memory (SRAM), electrically erasable programmable read-only memory (EEPROM), erasable programmable read-only memory (EPROM), programmable read-only memory (PROM), read-only memory (ROM), magnetic memory, flash memory, magnetic disk or optical disk. The readable storage medium can be any available medium that can be accessed by a general or special-purpose computer.

[0212] An exemplary readable storage medium is coupled to a processor so that the processor can read information from the readable storage medium and write information to the readable storage medium. Of course, the readable storage medium can also be a component of the processor. The processor and the readable storage medium can be located in an application specific integrated circuit (Application Specific Integrated Circuits, referred to as: ASIC). Of course, the processor and the readable storage medium can also exist in the device as discrete components.

[0213] The division of units is only a logical function division, and there may be other divisions in actual implementation, such as multiple units or components can be combined or integrated into another system, or some features can be ignored or not executed. Another point is that the mutual coupling or direct coupling or communication connection shown or discussed can be an indirect coupling or communication connection through some interface, device or unit, which can be electrical, mechanical or other forms.

[0214] The units described as separate components may or may not be physically separated, and the components shown as units may or may not be physical units, that is, they may be located in one place or distributed on multiple network units. Some or all of the units may be selected according to actual needs to achieve the purpose of the solution of this embodiment.

[0215] In addition, each functional unit in each embodiment of the present invention may be integrated into one processing unit, or each unit may exist physically separately, or two or more units may be integrated into one unit.

[0216] If the function is implemented in the form of a software functional unit and sold or used as an independent product, it can be stored in a computer-readable storage medium. Based on this understanding, the technical solution of the present invention, or the part that contributes to the prior art, or the part of the technical solution, can be embodied in the form of a software product. The computer software product is stored in a storage medium, including several instructions for a computer device (which can be a personal computer, server, or network device, etc.) to perform all or part of the steps of the methods of each embodiment of the present invention. The aforementioned storage medium includes: U disk, mobile hard disk, read-only memory (ROM, Read-Only Memory), random access memory (RAM, Random Access Memory), disk or optical disk, etc. Various media that can store program codes.

[0217] Those skilled in the art can understand that all or part of the steps of implementing the above-mentioned method embodiments can be completed by hardware related to program instructions. The aforementioned program can be stored in a computer-readable storage medium. When the program is executed, the steps of the above-mentioned method embodiments are executed; and the aforementioned storage medium includes: ROM, RAM, disk or optical disk and other media that can store program codes.

[0218] Finally, it should be noted that those skilled in the art will readily conceive of other embodiments of the present invention after considering the specification and practicing the invention disclosed herein. The present invention is intended to cover any variations, uses or adaptations of the present invention, which follow the general principles of the present invention and include common knowledge or customary technical means in the art not disclosed by the present invention, are not limited to the precise structure described above and shown in the drawings, and may be modified and changed in various ways without departing from the scope thereof. The scope of the present invention is limited only by the appended claims.

Claims

1. A mobile energy storage vehicle-mounted AC / DC converter, characterized in that: include: A T-type three-level inverter topology structure, a first switch, a second switch and a third switch; One end of the first switch is connected to the A-phase output end of the T-type three-level inverter topology structure, and the other end of the first switch serves as the A-phase output end of the mobile energy storage vehicle-mounted AC / DC converter; One end of the second switch is connected to the B-phase output end of the T-type three-level inverter topology structure, and the other end of the second switch serves as the B-phase output end of the mobile energy storage vehicle-mounted AC / DC converter; One end of the third switch is connected to the C-phase output end of the T-type three-level inverter topology structure, and the other end of the third switch serves as the C-phase output end of the mobile energy storage vehicle-mounted AC-DC converter; When the first switch and the third switch are both closed and the second switch is open, the mobile energy storage vehicle-mounted AC / DC converter outputs a DC voltage; when the first switch, the second switch and the third switch are all closed, the mobile energy storage vehicle-mounted AC / DC converter outputs an AC voltage.

2. The mobile energy storage vehicle-mounted AC / DC converter according to claim 1, characterized in that: Also includes: a fourth switch, one end of the fourth switch being connected to the midpoint of the filter capacitor of the T-type three-level inverter topology structure, and the other end of the fourth switch being connected to the midpoint of the three levels of the T-type three-level inverter topology structure; When the fourth switch is closed, the fourth switch tube of phase A is turned off, the second switch tube is turned on, the first switch tube and the third switch tube are driven complementarily, and the first switch tube of phase C is turned off, the third switch tube is turned on, and the fourth switch tube and the second switch tube are driven complementarily; When the fourth switch is disconnected, the fourth switch tube of phase A is turned off, the second switch tube is turned on, the first switch tube and the third switch tube are driven complementarily, and the first switch tube of phase C is turned off, the third switch tube is turned on, the fourth switch tube and the second switch tube are driven complementarily, and the first switch tube of phase A and the fourth switch tube of phase C are driven alternately.

3. The mobile energy storage vehicle-mounted AC / DC converter according to claim 1 or 2, characterized in that: The three-level of the T-type three-level inverter topology structure adopts a filter output, and the filter capacitor in the filter adopts a non-polarized capacitor.

4. A variable current control method, characterized in that: Used to control the mobile energy storage vehicle-mounted AC / DC converter according to any one of claims 1 to 3, the current conversion control method comprises: Obtaining voltage output requirements, where the voltage output requirements include direct current voltage output and alternating current voltage output; If the voltage output requirement is a DC voltage output, the first switch and the third switch are controlled to be closed, and the second switch is controlled to be opened; If the voltage output requirement is an AC voltage output, the first switch, the second switch and the third switch are all controlled to be closed.

5. The method according to claim 4, characterized in that The controlling the first switch and the third switch to be closed, and controlling the second switch to be opened, comprises: If the fourth switch is controlled to be closed, in the first period of the switching cycle, the first switch is controlled to be closed, the first switch tube of the A phase is turned on, the third switch tube of the A phase is turned off, and the first input capacitor of the T-type three-level inverter topology structure charges the first inductor and the first filter capacitor of the A phase; The third switch is controlled to be closed, the second switch tube of the C phase is turned off, and the fourth switch tube of the C phase is turned on, and the second input capacitor of the T-type three-level inverter topology structure charges the first inductor and the third filter capacitor of the C phase.

6. The method according to claim 5, characterized in that The method further comprises: In the second period of the switching cycle, the first switch is controlled to be closed, the first switch tube of the A phase is turned off, the third switch tube of the A phase is turned on, and the first filter capacitor freewheels the first inductor of the A phase; The third switch is controlled to be closed, the second switch tube of the C phase is turned on, the fourth switch tube of the C phase is turned off, and the third filter capacitor freewheels the first inductor of the C phase.

7. The method according to any one of claims 4 to 6, characterized in that The controlling the first switch and the third switch to be closed, and controlling the second switch to be opened, comprises: If the fourth switch is controlled to be disconnected, when the duty cycle is less than the first threshold, in the first period of the switching cycle, the first switch and the third switch are controlled to be closed, the first switch tube of the A phase is turned on, the third switch tube of the A phase is turned off, the second switch tube of the C phase is turned on, and the fourth switch tube of the C phase is turned off, and the first input capacitor charges the first inductor of the A phase, the first filter capacitor, the first inductor of the C phase, and the third filter capacitor; In the second time period of the switching cycle, the first switch and the third switch are controlled to be closed, the first switch tube of phase A is closed, the third switch tube of phase A is turned on, the second switch tube of phase C is turned on, and the fourth switch tube of phase C is closed, and the first filter capacitor and the third filter capacitor are used to freewheel the first inductor of phase A and the first inductor of phase C.

8. The method according to claim 7, characterized in that The method further comprises: In a third period of the switching cycle, the first switch and the third switch are controlled to be closed, the first switch tube of the A phase is turned off, the third switch tube of the A phase is turned on, the second switch tube of the C phase is turned off, and the fourth switch tube of the C phase is turned on, and the second input capacitor charges the first inductor of the A phase, the first filter capacitor, the first inductor of the C phase, and the third filter capacitor; In the fourth time period of the switching cycle, the first switch and the third switch are controlled to be closed, the first switch tube of phase A is closed, the third switch tube of phase A is turned on, the second switch tube of phase C is turned on, and the fourth switch tube of phase C is closed, and the first filter capacitor and the third filter capacitor are used to freewheel the first inductor of phase A and the first inductor of phase C.

9. The method according to claim 7, characterized in that: The method further comprises: When the duty cycle is greater than a first threshold value, in a first period of the switching cycle, the first switch and the third switch are controlled to be closed, the first switch tube of the A phase is turned on, the third switch tube of the A phase is turned off, the second switch tube of the C phase is turned off, and the fourth switch tube of the C phase is turned on, and the first input capacitor and the second input capacitor charge the first inductor of the A phase, the first filter capacitor, the first inductor of the C phase, and the third filter capacitor; In the second time period of the switching cycle, the first switch and the third switch are controlled to be closed, the first switch tube of phase A is turned on, the third switch tube of phase A is turned off, the second switch tube of phase C is turned on, and the fourth switch tube of phase C is turned off, and the first input capacitor, the first filter capacitor, and the third filter capacitor are used to freewheel the first inductor of phase A and the first inductor of phase C.

10. The method according to claim 9, characterized in that The method further comprises: In a third period of the switching cycle, the first switch and the third switch are controlled to be closed, the first switch tube of the A phase is turned on, the third switch tube of the A phase is turned off, the second switch tube of the C phase is turned off, and the fourth switch tube of the C phase is turned on, and the first input capacitor and the second input capacitor charge the first inductor of the A phase, the first filter capacitor, the first inductor of the C phase, and the third filter capacitor; In the fourth time period of the switching cycle, the first switch and the third switch are controlled to be closed, the first switch tube of phase A is turned off, the third switch tube of phase A is turned on, the second switch tube of phase C is turned off, and the fourth switch tube of phase C is turned on, and the second input capacitor, the first filter capacitor, and the third filter capacitor are used to freewheel the first inductor of phase A and the first inductor of phase C.

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