A switching method, control device and charging pile for a power module

Abstract

The present invention provides a switching method, a control device and a charging pile for a power module, including obtaining the required power during vehicle charging and the output power of a first power module; determining a switching mode according to the required power and the output power of the first power module; if it is an adding-module mode, establishing a connection between a second power module and a DC bus, controlling the output powers of the first power module and the second power module, and if the first power module and the second power module meet a first preset condition, the switching is completed; if it is a deleting-module mode, controlling the output powers of a first sub-power module and a second sub-power module in the first power module, and if the second sub-power module meets a second preset condition, disconnecting the second sub-power module from the DC bus to complete the switching. By the above method, the notch fluctuation phenomenon during power module switching can be reduced, and the charging stability and safety can be increased.

Description

Technical Field

[0001] The embodiments of the present invention relate to the field of electronic technology, and particularly to a method for switching power modules, a control device, and a charging pile. Background Art

[0002] With the rapid development of new energy technology, the number of electric vehicles is increasing, and the demand for charging infrastructure is also increasing. The common charging piles on the market at present are divided into AC charging piles and DC charging piles, and the charging power of DC charging piles is much greater than that of AC charging piles.

[0003] Generally, for a DC charging pile, it outputs power to the DC bus through multiple power modules, and there will be output switching between power modules when outputting power through multiple power modules to meet different charging power requirements. However, when multiple power modules switch simultaneously to the same DC bus, there will be a large concave groove fluctuation phenomenon between the output power on the DC bus and the required power of the vehicle, that is, the difference between the output power of the DC bus and the required power of the vehicle is large, as shown by the concave grooves a and b in Figure 1 This concave groove fluctuation phenomenon will affect the stability when the charging pile charges the vehicle. Summary of the Invention

[0004] The purpose of the embodiments of the present invention is to provide a method for switching power modules, a control device, and a charging pile, which can reduce the difference between the output power of the DC bus and the required power of the vehicle when the power modules are switched, reduce the concave groove fluctuation phenomenon, and thus increase the stability and safety of the charging pile when charging externally.

[0005] To solve the above technical problems, a technical solution adopted in the embodiments of the present invention is: to provide a method for switching power modules, which is applied to a charging pile, and the switching method includes: obtaining the required power when the vehicle is charging and the output power of the first power module; determining a switching mode according to the required power and the output power of the first power module; if the switching mode is the adding module mode, establishing a connection between the second power module and the DC bus, controlling the output powers of the first power module and the second power module, and if the first power module and the second power module meet a first preset condition, the switching is completed; if the switching mode is the deleting module mode, controlling the output powers of the first sub-power module and the second sub-power module in the first power module, and if the second sub-power module meets a second preset condition, disconnecting the second sub-power module from the DC bus to complete the switching.

[0006] In some embodiments, determining the switching mode according to the required power and the output power of the first power module includes: if the required power is greater than the percentage power of the output power of the first power module, the switching mode is the module adding mode; if the required power is less than the percentage power, the switching mode is the module deleting mode.

[0007] In some embodiments, controlling the output powers of the first power module and the second power module, and if the first power module and the second power module meet a first preset condition, completing the switching includes: determining whether a first adjustment period is reached; if so, controlling the output power of the first power module to decrease by a first power value and the output power of the second power module to increase by the first power value; obtaining the total decreased power value of the first power module and the total increased power value of the second power module; if the total decreased power value is equal to the total increased power value, completing the module adding; if the total decreased power value is not equal to the total increased power value, re-determining whether the first adjustment period is reached.

[0008] In some embodiments, determining whether the first adjustment period is reached includes: obtaining a first duration after the charging pile enters the module adding mode; if the first duration is greater than a first preset time, ending the module adding; if the first duration is less than or equal to the first preset time, determining whether the first adjustment period is reached.

[0009] In some embodiments, controlling the output powers of the first sub-power module and the second sub-power module in the first power module, and if the second sub-power module meets a second preset condition, disconnecting the second sub-power module from the DC bus to complete the switching includes: determining whether a second adjustment period is reached; if so, controlling the output power of the first sub-power module to increase by a first power value and the output power of the second sub-power module to decrease by the first power value; obtaining the output power of the second sub-power module; if the output power of the second sub-power module is equal to 0, disconnecting the second sub-power module from the DC bus; if the output power of the second sub-power module is not equal to 0, re-determining whether the second adjustment period is reached.

[0010] In some embodiments, determining whether the second adjustment period is reached includes: obtaining a second duration after the charging pile enters the module deleting mode; if the second duration is greater than a second preset time, ending the module deleting; if the second duration is less than or equal to the second preset time, determining whether the second adjustment period is reached.

[0011] In some embodiments, the first power value is obtained by the following formula:

[0012] ΔP = (|P1 - P2|) / (N × k);

[0013] Wherein, ΔP is the first power value, k is the adjustment speed coefficient, N is the total number of power modules, P1 is the required power, and P2 is the output power of the first power module.

[0014] In some embodiments, the charging pile further includes a switching device; establishing the connection between the second power module and the DC bus includes: closing the switching device corresponding to the connection with the second power module so that the second power module is connected to the DC bus through the corresponding switching device; disconnecting the connection between the second sub-power module and the DC bus includes: disconnecting the switching device corresponding to the connection with the second sub-power module so that the second sub-power module is connected to the DC bus through the corresponding switching device.

[0015] In a second aspect, an embodiment of the present invention provides a control device, which includes: at least one processor; and a memory communicatively connected to the at least one processor; wherein, the memory stores instructions executable by the at least one processor, and the instructions are executed by the at least one processor so that the at least one processor can execute the switching method according to any one of the above first aspects.

[0016] In a third aspect, an embodiment of the present invention further provides a charging pile, which includes: a power module, a switching device, and the control device according to the second aspect above; the power module is connected to the DC bus through the switching device, and the control device is respectively connected to the power module and the switching device.

[0017] In a fourth aspect, an embodiment of the present invention further provides a computer-readable storage medium, which stores computer-executable instructions for causing a computer to execute the method according to the first aspect above.

[0018] In a fifth aspect, an embodiment of the present invention further provides a computer program product, which includes a computer program stored on a computer-readable storage medium, and the computer program includes program instructions that, when executed by a computer, cause the computer to execute the method according to the first aspect above.

[0019] Compared with the prior art, the beneficial effects of the present invention are as follows: The embodiments of the present invention provide a switching method for a power module, a control device, and a charging pile. The switching method includes: obtaining the required power during vehicle charging and the output power of the first power module; determining a switching mode according to the required power and the output power of the first power module; if the switching mode is the module adding mode, establishing a connection between the second power module and the DC bus, controlling the output powers of the first power module and the second power module, and if the first power module and the second power module meet the first preset condition, the switching is completed; if the switching mode is the module deleting mode, controlling the output powers of the first sub-power module and the second sub-power module in the first power module, and if the second sub-power module meets the second preset condition, disconnecting the second sub-power module from the DC bus to complete the switching. Through the above method, the difference between the output power of the DC bus and the required power of the vehicle during power module switching can be reduced, and the trough fluctuation phenomenon can be reduced, thereby increasing the stability and safety of the charging pile during external charging. BRIEF DESCRIPTION OF THE DRAWINGS

[0020] In one or more embodiments, exemplary illustrations are provided through the pictures in the corresponding drawings. These exemplary illustrations do not limit the embodiments. Elements / modules and steps with the same reference numerals in the drawings represent similar elements / modules and steps. Unless otherwise stated, the drawings in the figures do not constitute a scale limitation.

[0021] Figure 1 is a schematic diagram of the required power of the vehicle and the output power of the DC bus during the charging process of a charging pile in the prior art;

[0022] Figure 2 is a schematic structural diagram of a charging pile provided by an embodiment of the present invention;

[0023] Figure 3 is a schematic structural diagram of a control device provided by an embodiment of the present invention;

[0024] Figure 4 is a schematic flow chart of a switching method provided by an embodiment of the present invention;

[0025] Figure 5 is a schematic diagram of the required power of the vehicle and the output power of the DC bus during the charging process of a charging pile in an embodiment of the present invention;

[0026] Figure 6 is a schematic flow chart of step S20 provided by an embodiment of the present invention;

[0027] Figure 7 is a partial schematic flow chart of a switching method provided by an embodiment of the present invention;

[0028] Figure 8It is a schematic flowchart of step S31 provided by an embodiment of the present invention;

[0029] Figure 9 It is a partial schematic flowchart of another switching method provided by an embodiment of the present invention;

[0030] Figure 10 It is a schematic flowchart of step S41 provided by an embodiment of the present invention. Detailed implementation manners

[0031] The present invention will be described in detail below in conjunction with specific embodiments. The following embodiments will help those skilled in the art to further understand the present invention, but do not limit the present invention in any form. It should be noted that those of ordinary skill in the art can make several modifications and improvements without departing from the concept of the present invention. These all belong to the protection scope of the present invention.

[0032] For the convenience of understanding the present application, the present application will be described in more detail below in conjunction with the accompanying drawings and specific embodiments. Unless otherwise defined, all technical and scientific terms used in this specification have the same meaning as commonly understood by those skilled in the technical field to which this application belongs. The terms used in the specification of this application are only for the purpose of describing specific embodiments and are not used to limit this application. The term "and / or" used in this specification includes any and all combinations of one or more of the related listed items.

[0033] It should be noted that if there is no conflict, the various features in the embodiments of the present invention can be combined with each other, and all are within the protection scope of this application. In addition, although functional module division is performed in the device schematic diagram, in some cases, it can be different from the module division in the device. In addition, the terms "first", "second", etc. used herein do not limit the data and execution order, but only distinguish the same items or similar items with basically the same function and role.

[0034] In a first aspect, an embodiment of the present invention provides a charging pile, which includes: a power module, a switching device, and a control device. The power module is connected to the DC bus through the switching device, and the control device is respectively connected to the power module and the switching device.

[0035] Specifically, please refer to Figure 2, the charging pile includes a power module 11, a switching device 21, a power module 12, and a switching device 22. Among them, the output end of the power module 11 is connected to the first end of the switching device 21, the output end of the power module 12 is connected to the first end of the switching device 12, and the second ends of the switching device 21 and the switching device 22 are connected to the DC bus 100. In this way, the connection between the power module 11, the power module 12 and the DC bus 100 can be controlled by controlling the switching device 21 and the switching device 22. In practical applications, the number of power modules set in the charging pile can be set according to actual needs, and there is no need to be restricted by the limitations in this embodiment.

[0036] For example, when the switching device 21 is closed and the switching device 22 is closed, the power module 11 is connected to the DC bus 100, and the power module 12 is connected to the DC bus 100. At this time, the output power on the DC bus 100 is the sum of the output power of the power module 11 and the output power of the power module 12, and there are power modules that can be deleted at this time. For example, the power module 11 or the power module 12 can be deleted, that is, the switching device 21 or the switching device 22 is disconnected, so that the power module 11 is disconnected from the DC bus 100, or the power module 12 is disconnected from the DC bus 100. When the switching device 21 is closed and the switching device 22 is disconnected, the power module 11 is connected to the DC bus 100, and the power module 12 is not connected to the DC bus 100. At this time, the output power on the DC bus 100 is only the output power of the power module 11, and there are power modules that can be added. For example, the switching device 22 can be re-closed to reconnect the power module 12 to the DC bus 100. When the switching device 21 is disconnected and the switching device 22 is closed, the power module 11 is not connected to the DC bus 100, and the power module 12 is connected to the DC bus 100. At this time, the output power on the DC bus 100 is only the output power of the power module 12, and there are power modules that can be added. For example, the switching device 21 can be re-closed to reconnect the power module 11 to the DC bus 100. When the switching device 21 is disconnected and the switching device 22 is disconnected, the power module 11 is not connected to the DC bus 100, and the power module 12 is not connected to the DC bus 100. At this time, the output power on the DC bus 100 is 0, and there are power modules that can be added. For example, the switching device 21 can be re-closed to reconnect the power module 11 to the DC bus 100, and / or the switching device 22 can be re-closed to reconnect the power module 12 to the DC bus 100.

[0037] Among them, the control device can adopt a microcontroller of the STM8, STM16 or STM32 series, or any other suitable microcontrol processor that can be used to receive, process, store and output data. The control device has the same structure and function as the control device described in the following second aspect, and can be used to execute the switching method of the power module described in any one of the embodiments provided by the present invention. For the specific method, please refer to the following description and will not be elaborated here.

[0038] The power module includes at least one power module. In the power module, the input ends of the power modules are connected to an AC power supply, the output ends of the power modules are connected to corresponding switching devices, and the control ends of the power modules are connected to a control device. The power module can output power to the DC bus under the control of the control device. The power module can be an ACDC module or a combination between an ACDC module and a DCDC module, and can be set according to actual needs in practical applications and will not be limited here. The specific circuit structure of the power module can refer to the prior art and will not be limited here.

[0039] The switching device can include at least one power switch tube, such as a DC contactor, an Insulated Gate Bipolar Transistor (IGBT) device, an Integrated Gate-Commutated Thyristor (IGCT) device, a Gate Turn-Off Thyristor (GTO) device, a Silicon Controlled Rectifier (SCR) device, a Junction Field-Effect Transistor (JFET) device, a Mos Controlled GTO (MCT) device, a gallium nitride (GaN)-based power device, a silicon carbide (SiC)-based power device, etc. The specific quantity and type can be set according to actual needs and will not be limited here.

[0040] In the charging pile provided by the embodiment of the present invention, the control device can execute any one of the switching methods provided by the embodiment of the present invention, can reduce the difference between the output power of the DC bus and the vehicle demand power during the switching of the power module, and reduce the notch fluctuation phenomenon, thereby increasing the stability and safety of the charging pile during external charging.

[0041] Second aspect, the embodiment of the present invention provides a control device, please refer to Figure 3 , which shows the hardware structure capable of executing Figure 4 , Figures 6 to 10 the switching method of the power module described above. The control device can beFigure 2 The control device shown

[0042] The control device includes: at least one processor 31; and a memory 32 communicatively connected to the at least one processor 31, Figure 3 Taking one processor 31 as an example. The memory 32 stores instructions executable by the at least one processor 31, and the instructions are executed by the at least one processor 31 so that the at least one processor 31 can execute the following Figure 4 、 Figures 6 to 10 The switching method described. The processor 31 and the memory 32 may be connected by a bus or other means, Figure 3 Taking connection by bus as an example.

[0043] The memory 32, as a non-volatile computer-readable storage medium, can be used to store non-volatile software programs, non-volatile computer-executable programs, and modules, such as the program instructions / modules corresponding to the execution switching method in the embodiments of the present application. The processor 31 executes various functional applications and data processing of the server by running the non-volatile software programs, instructions, and modules stored in the memory 32, that is, implements the switching method described in the following method embodiments.

[0044] The memory 32 may include a program storage area and a data storage area. Among them, the program storage area can store an operating system and application programs required for at least one function; the data storage area can store data created according to the use of the pixel correction device, etc. In addition, the memory 32 may include a high-speed random access memory, and may also include a non-volatile memory, such as at least one magnetic disk storage device, a flash memory device, or other non-volatile solid-state storage devices. In some of these embodiments, the memory 32 may optionally include a memory remotely provided with respect to the processor 31, and these remote memories can be connected to the pixel correction device through a network. Examples of the above networks include but are not limited to the Internet, an enterprise intranet, a local area network, a mobile communication network, and combinations thereof.

[0045] The one or more modules are stored in the memory 32 and, when executed by the one or more processors 31, execute the switching method described in any of the following method embodiments. For example, execute the Figure 4 、 Figures 6 to 10 Method steps.

[0046] The above product can execute the method provided by the embodiments of the present application, and has corresponding functional modules and beneficial effects for executing the method. For technical details not described in detail in this embodiment, reference can be made to the method provided by the embodiments of the present application.

[0047] In a third aspect, an embodiment of the present invention provides a method for switching power modules, which is characterized in that it is applied to a charging pile. Please refer to Figure 4 , and the switching method includes:

[0048] Step S10: Obtain the required power during vehicle charging and the output power of the first power module.

[0049] Specifically, when the charging pile is connected to the vehicle through the DC bus, the control device communicates with the vehicle's battery management system, so that the required power during vehicle charging can be obtained in real time.

[0050] The first power module is a power module that has been connected to the DC bus and can output power to the DC bus at the initial moment when the DC bus is connected to the vehicle. For example, at the initial moment, in Figure 2 , if both the switch device 21 and the switch device 22 are closed, the first power module includes the power module 11 and the power module 12. At this time, the number of power modules in the first power module is 2; if the switch device 21 is closed and the switch device 22 is open, the first power module only includes the power module 11. At this time, the number of power modules in the first power module is 1; if the switch device 21 is open and the switch device 22 is closed, the first power module only includes the power module 12. At this time, the number of power modules in the first power module is 1.

[0051] When obtaining the output power of the first power module, the output voltage and output current on the DC bus can be obtained, and the output power of the first power module can be calculated through the output voltage and output current. In practical applications, a voltage sampling unit and a current sampling unit can be set on the DC bus. In this way, the output voltage on the DC bus can be obtained through the voltage sampling unit, and the output current on the DC bus can be obtained through the current sampling unit. Among them, the voltage sampling unit and the current sampling unit can adopt all suitable devices in the prior art.

[0052] Step S20: Determine the switching mode according to the required power and the output power of the first power module.

[0053] It can be understood that if the required power is greater than the output power of the first power module, it means that the number of power modules currently connected to the DC bus is insufficient and the number of power modules needs to be increased. Then, the switching mode is determined as the mode of adding modules. If the required power is less than the output power of the first power module, it means that the number of power modules currently connected to the DC bus is redundant and the number of power modules needs to be reduced. Then, the switching mode is determined as the mode of deleting modules. If the required power is equal to the output power of the first power module, it means that the number of power modules currently connected to the DC bus is exactly appropriate, and neither adding nor deleting modules is required.

[0054] Step S30: If the switching mode is the adding module mode, establish the connection between the second power module and the DC bus, control the output powers of the first power module and the second power module. If the first power module and the second power module meet the first preset condition, the switching is completed.

[0055] Among them, the second power module is the power module that is not connected to the DC bus at the initial moment. For example, at the initial moment, Figure 2 in, if the switch device 21 is closed and the switch device 22 is open, the second power module only includes the power module 12, and the number of power modules in the second power module is 1. If the switch device 21 is open and the switch device 22 is closed, the second power module only includes the power module 11, and the number of power modules in the second power module is 1. If both the switch device 21 and the switch device 22 are open, the second power module includes the power module 11 and the power module 12, and the number of power modules in the second power module is 2.

[0056] After entering the adding module mode, after establishing the connection between the second power module and the DC bus, correct the output powers of the first power module and the second power module. When they meet the first preset condition, end the adding module process and complete the switching.

[0057] Step S40: If the switching mode is the deleting module mode, control the output powers of the first sub-power module and the second sub-power module in the first power module. If the second sub-power module meets the second preset condition, disconnect the second sub-power module from the DC bus to complete the switching.

[0058] Among them, the first sub-power module and the second sub-power module are the power modules that are connected to the DC bus at the initial moment. For example, at the initial moment, Figure 2 in, if both the switch device 21 and the switch device 22 are closed, the first sub-power module may include the power module 11, and the second sub-power module may include the power module 12. At this time, the number of power modules in the first sub-power module and the number of power modules in the second sub-power module are both 1; or, the first sub-power module may include the power module 12, and the second sub-power module may include the power module 11. The number of power modules in the first sub-power module and the number of power modules in the second sub-power module are both 1.

[0059] After entering the deleting module mode, the output powers of the first sub-power module and the second sub-power module can be corrected. When they meet the second preset condition, disconnect the second sub-power module from the DC bus to end the deleting module process and complete the switching.

[0060] In this switching method, after entering the module addition mode or the module deletion mode, the output power of each power module connected to the DC bus is controlled to correct the output power on the DC bus, keep the total output power of the entire DC bus unchanged or reduce fluctuations, and complete the module addition and deletion process. When adding or deleting modules in this way, as Figure 5 shown, the difference between the output power on the DC bus and the vehicle demand power can be reduced, thereby reducing the phenomenon of groove fluctuations and increasing the stability and safety of the charging pile when charging externally.

[0061] In some embodiments, please refer to Figure 6 , step S20 includes:

[0062] Step S21: If the demand power is greater than the percentage power of the output power of the first power module, the switching mode is the module addition mode;

[0063] Step S22: If the demand power is less than the percentage power, the switching mode is the module deletion mode.

[0064] Among them, the percentage power is the output power of the first power module multiplied by the power value of a preset percentage. The value of the preset percentage can be set by the charging pile designer according to the efficiency of the power module by himself. For example, the preset percentage can be selected as a value in the range of 50%-95%. Compared with the method of directly comparing the demand power with the output power of the first power module, in the embodiments of the present invention, by comparing the demand power during vehicle charging with the percentage power in real time and considering the efficiency of the power module, the accuracy of determining the switching mode can be improved.

[0065] In some embodiments, the charging pile further includes a switching device. The establishing the connection between the second power module and the DC bus includes: closing the switching device corresponding to the connection with the second power module so that the second power module is connected to the DC bus through the corresponding switching device. The disconnecting the connection between the second sub-power module and the DC bus includes: disconnecting the switching device corresponding to the connection with the second sub-power module so that the second sub-power module is connected to the DC bus through the corresponding switching device.

[0066] Specifically, at the initial moment, in Figure 2 , if the switching device 21 is closed, the switching device 22 is disconnected, and the module addition mode is entered at this time. If the power module 12 is to be added, the switching device 22 can be closed. At the initial moment, in Figure 2 , if both the switching device 21 and the switching device 22 are closed, and the module deletion mode is entered at this time, then if the power module 12 is to be deleted, the switching device 22 is disconnected.

[0067] It can be seen that by controlling the switching device connected to the power module correspondingly, the power module can be reconnected or disconnected from the DC bus, so that the charging pile can achieve the purpose of adding or deleting modules.

[0068] In some of these embodiments, refer to Figure 7 , controlling the output powers of the first power module and the second power module. If the first power module and the second power module meet a first preset condition, then the switching is completed, including:

[0069] Step S31: Determine whether the first adjustment period is reached;

[0070] Step S32: If so, control the output power of the first power module to decrease by a first power value and the output power of the second power module to increase by the first power value;

[0071] Step S33: Obtain the total decreased power value of the first power module and the total increased power value of the second power module;

[0072] Step S34: If the total decreased power value is equal to the total increased power value, then the module addition is completed;

[0073] Step S35: If the total decreased power value is not equal to the total increased power value, then re-determine whether the first adjustment period is reached.

[0074] Among them, the first adjustment period is the time for interval execution of steps S32 to S35. Specifically, the first adjustment period can be set between 500 ms and 2000 ms. For example, when the first adjustment period is set to 500 ms, that is, after entering the module addition mode, the output powers of the first power module and the second power module are controlled every 500 ms until the total decreased power value is equal to the total increased power value, and the switching is completed.

[0075] Specifically, at the initial moment, in Figure 2 , if the switching device 21 is closed, the switching device 22 is open, and the module addition mode is entered at this time, if it is necessary to add the power module 12, then after closing the switching device 22, confirm whether the first adjustment period is reached at this time. If so, control the output power of the power module 11 to decrease by a first power value ΔP and control the output power of the power module 12 to increase by the first power value ΔP; then, obtain the total decreased power value of the power module 11 and the total increased power value of the power module 12 before and after controlling the output power; then, determine whether the total decreased power value is equal to the total increased power value. If so, the module addition process is completed. If not, re-confirm whether the next first adjustment period is reached.

[0076] Among them, when obtaining the total power reduction value of the power module 11, the output power of the power module 11 can be obtained first before controlling the output power of the power module 11 to decrease by the first power value ΔP. Then, when the control of the output power of the power module 11 to decrease by the first power value ΔP is completed, the output power of the power module 11 is obtained again. Finally, the absolute value of the difference between the two is taken to obtain the total power reduction value of the power module 11. Similarly, when obtaining the total power increase value of the power module 12, the output power of the power module 12 can be obtained first before controlling the output power of the power module 12 to increase by the first power value ΔP. Then, when the control of the output power of the power module 12 to increase by the first power value ΔP is completed, the output power of the power module 12 is obtained again. Finally, the absolute value of the difference between the two is taken to obtain the total power increase value of the power module 12.

[0077] In the embodiment of the present invention, by periodically adjusting the power outputs of the first power module and the second power module, the total power reduction value is made equal to the total power increase value. By smoothing and balancing the output powers of the first power module and the second power module, the overall output total power on the DC bus can be kept unchanged or have a small fluctuation, and the module addition process can be completed. Thus, the difference between the output power on the DC bus and the vehicle demand power can be reduced, thereby reducing the notch fluctuation phenomenon and increasing the stability and safety of the charging pile during external charging.

[0078] In some of the embodiments, please refer to Figure 8 , the step S31 includes:

[0079] Step S311: Obtain the first duration after the charging pile enters the module addition mode;

[0080] Step S312: If the first duration is greater than the first preset time, end the module addition;

[0081] Step S313: If the first duration is less than or equal to the first preset time, determine whether the first adjustment period is reached.

[0082] Specifically, after entering the module addition mode, a timer can be started to obtain the first duration after the charging pile enters the addition mode. The first preset time can be set between 20 s and 50 s. By setting the first preset time, it is possible to avoid the phenomenon that the charging pile always fails to meet the first preset condition during power correction and the control process enters an infinite loop after entering the module addition mode, thereby improving the reliability of the power module addition process.

[0083] In some of the embodiments, please refer to Figure 9controlling the output powers of the first sub - power module and the second sub - power module in the first power module, and if the second sub - power module meets the second preset condition, disconnecting the connection between the second sub - power module and the DC bus to complete the switching, including:

[0084] Step S41: Determine whether the second adjustment period is reached;

[0085] Step S42: If so, control the output power of the first sub - power module to increase by a first power value and the output power of the second sub - power module to decrease by the first power value;

[0086] Step S43: Obtain the output power of the second sub - power module;

[0087] Step S44: If the output power of the second sub - power module is equal to 0, disconnect the connection between the second sub - power module and the DC bus;

[0088] Step S45: If the output power of the second sub - power module is not equal to 0, re - determine whether the second adjustment period is reached.

[0089] Among them, the second adjustment period is the time for interval execution of steps S42 to S45. Specifically, the second adjustment period can be set between 500 ms and 2000 ms. For example, when the first adjustment period is set to 500 ms, that is, after entering the module deletion mode, the output powers of the first sub - power module and the second sub - power module are controlled every 500 ms until the total decreased power value is equal to the total increased power value, and then the connection between the second sub - power module and the DC bus is disconnected to complete the switching.

[0090] Specifically, at the initial moment, in Figure 2 if both the switch device 21 and the switch device 22 are closed and the module deletion mode is entered at this time, if the first sub - power module is the power module 11 and the second sub - power module is the power module 12 at this time, confirm whether the second adjustment period is reached. If so, control the output power of the power module 11 to increase by a first power value ΔP and control the output power of the power module 12 to decrease by the first power value ΔP; then, obtain the output power of the power module 12 when the output power of the power module 12 is controlled to decrease by the first power value ΔP; then, determine whether the output power of the power module 12 is equal to 0. If so, disconnect the switch device 22 to complete the module deletion process. If not, re - confirm whether the next second adjustment period is reached.

[0091] In the embodiments of the present invention, by periodically adjusting the power outputs of the first sub-power module and the second sub-power module, the power output of the second sub-power module is made equal to 0, and all the vehicle demand power is provided by the first sub-power module. Moreover, by smoothly equalizing the output powers of the first sub-power module and the second sub-power module, the overall output total power on the DC bus can be kept unchanged or fluctuates less, and the module deletion process can be completed. Thus, the difference between the output power on the DC bus and the vehicle demand power can be reduced, the notch fluctuation phenomenon can be reduced, and the stability and safety of the charging pile during external charging can be increased.

[0092] In some of the embodiments, please refer to Figure 10 , the step S41 includes:

[0093] Step S411: Obtain the second duration after the charging pile enters the module deletion mode;

[0094] Step S412: If the second duration is greater than the second preset time, end the module deletion;

[0095] Step S413: If the second duration is less than or equal to the second preset time, determine whether the second adjustment period is reached.

[0096] Specifically, after entering the module deletion mode, a timer can be started to obtain the second duration after the charging pile enters the deletion mode. The second preset time can be set between 20 s and 50 s. By setting the second preset time, it is possible to avoid the phenomenon that the charging pile always fails to meet the second preset condition during power correction and the control process enters an infinite loop after entering the module deletion mode, thereby improving the reliability of the power module deletion process.

[0097] In some of the embodiments, the first power value is obtained by the following formula:

[0098] ΔP = (|P1 - P2|) / (N×k);

[0099] Wherein, ΔP is the first power value, k is the adjustment speed coefficient, N is the total number of power modules, P1 is the demand power, and P2 is the output power of the first power module.

[0100] Specifically, the adjustment speed coefficient can be set according to the adjustment response speed of the power module. It can be understood that the faster the response speed of the power module, the larger the adjustment speed coefficient. When the switching mode is in the module addition mode, N is the sum of the number of power modules in the first power module and the number of power modules in the second power module. When the switching mode is in the module deletion mode, N is the number of power modules in the first power module, that is, the sum of the number of power modules in the first sub-power module and the number of power modules in the second sub-power module.

[0101] Fourthly, an embodiment of the present application further provides a non-volatile computer-readable storage medium storing computer-executable instructions, which are executed by one or more processors. For example, the method steps described above are executed Figure 4 、 Figures 6 to 10 .

[0102] Fifthly, an embodiment of the present application further provides a computer program product, including a computing program stored on a non-volatile computer-readable storage medium. The computer program includes program instructions. When the program instructions are executed by a computer, the computer is caused to execute the switching method in any of the above method embodiments. For example, the method steps described above are executed Figure 4 、 Figures 6 to 10 .

[0103] It should be noted that the device embodiments described above are merely illustrative. 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 to multiple network units. Some or all of the modules can be selected according to actual needs to achieve the purpose of the solution of this embodiment.

[0104] Through the description of the above embodiments, those skilled in the art can clearly understand that each embodiment can be implemented by means of software plus a general hardware platform, and of course, it can also be implemented by hardware. Based on such an understanding, the essence of the above technical solution, or the part that contributes to the related technology, can be embodied in the form of a software product. The computer software product can be stored in a computer-readable storage medium, such as ROM / RAM, magnetic disk, optical disk, etc., and includes several instructions to execute the methods described in each embodiment or some parts of the embodiments by at least one computer device (which can be a personal computer, a server, or a network device, etc.).

[0105] Finally, it should be noted that the above embodiments are only used to illustrate the technical solutions of the present invention, rather than to limit them; under the idea of the present invention, the technical features in the above embodiments or different embodiments can also be combined, and the steps can be implemented in any order, and there are many other variations in different aspects of the present invention as described above. For the sake of brevity, they are not provided in detail; although the present invention has been described in detail with reference to the foregoing embodiments, those of ordinary skill in the art should understand that they can still modify the technical solutions described in the foregoing embodiments, or perform equivalent replacements on some of the technical features; and these modifications or replacements do not make the essence of the corresponding technical solutions deviate from the scope of the technical solutions of the embodiments of the present invention.

Claims

1. A switching method for a power module, characterized in that, applied to a charging pile, the switching method includes: Obtaining the required power during vehicle charging and the output power of the first power module; If the required power is greater than the percentage power of the output power of the first power module, the switching mode is the module adding mode; if the required power is less than the percentage power, the switching mode is the module deleting mode; If the switching mode is the module adding mode, establish the connection between the second power module and the DC bus, control the output powers of the first power module and the second power module, obtain the first duration after the charging pile enters the module adding mode. If the first duration is greater than the first preset time, end the module adding; if the first duration is less than or equal to the first preset time, determine whether the first adjustment period is reached. If so, control the output power of the first power module to decrease by a first power value, and the output power of the second power module to increase by the first power value. Obtain the total decreased power value of the first power module and the total increased power value of the second power module. If the total decreased power value is equal to the total increased power value, complete the module adding; if the total decreased power value is not equal to the total increased power value, re-determine whether the first adjustment period is reached; If the switching mode is the module deleting mode, obtain the second duration after the charging pile enters the module deleting mode. If the second duration is greater than the second preset time, end the module deleting; if the second duration is less than or equal to the second preset time, determine whether the second adjustment period is reached. If so, control the output power of the first sub-power module in the first power module to increase by a first power value, and the output power of the second sub-power module in the first power module to decrease by the first power value. Obtain the output power of the second sub-power module. If the output power of the second sub-power module is equal to 0, disconnect the second sub-power module from the DC bus to complete the switching; if the output power of the second sub-power module is not equal to 0, re-determine whether the second adjustment period is reached.

2. The switching method according to claim 1, characterized in that, the first power value is obtained by the following formula: ΔP = (|P1 - P2|) / (N × k); where, ΔP is the first power value, k is the adjustment speed coefficient, N is the total number of power modules, P1 is the required power, and P2 is the output power of the first power module.

3. The switching method according to any one of claims 1-2, characterized in that, the charging pile further includes a switching device; The establishing the connection between the second power module and the DC bus includes: Closing the switching device corresponding to the connection with the second power module, so that the second power module is connected to the DC bus through the corresponding switching device; The disconnecting the second sub-power module from the DC bus includes: Disconnect the switching device corresponding to the connection with the second sub-power module, so that the second sub-power module is connected to the DC bus through the corresponding switching device.

4. A control device, characterized in that, it includes: at least one processor; and, a memory communicatively connected to the at least one processor; wherein, the memory stores instructions executable by the at least one processor, and the instructions are executed by the at least one processor so that the at least one processor can execute the switching method described in any one of 1-3.

5. A charging pile, characterized in that, it includes: a power module, a switching device, and the control device according to claim 4; the power module is connected to the DC bus through the switching device, and the control device is respectively connected to the power module and the switching device.

6. A computer-readable storage medium, characterized in that, the computer-readable storage medium stores computer-executable instructions for causing a computer to execute the switching method described in any one of 1-3.

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