DC charging pile and control method thereof

Abstract

The present disclosure relates to a DC charging pile and a control method thereof. The DC charging pile comprises: a power distribution module, a DC-DC module, an energy storage module, an AC-DC module, and a charging terminal; a first end of the power distribution module is connected to the energy storage module via the DC-DC module, a second end of the power distribution module is connected to the AC power grid via the AC-DC module, and a third end of the power distribution module is connected to the charging terminal; the charging terminal is used to obtain the temperature of the power battery and, based on the temperature, control the power distribution module to switch the working mode of the power battery between a heating mode, a charging mode, and a heating and charging synchronous mode. Thus, by adding a power distribution module and controlling the power distribution module based on the temperature of the power battery, the power battery can achieve a heating and charging synchronous mode, shortening the time required for the entire charging process and greatly improving the charging speed of the power battery at low temperatures.

Description

Technical Field

[0001] The present disclosure relates to the technical field of charging piles, and in particular to a DC charging pile and a control method thereof. Background Art

[0002] At present, the power batteries of vehicles such as new energy vehicles mainly use lithium batteries. The working characteristics of lithium batteries are significantly affected by their temperature, especially at low temperatures. The electrochemical reaction activity of lithium batteries is reduced, and the charging and discharging performance decays very seriously. In addition, low-temperature charging may cause lithium ion precipitation and accumulation, seriously affecting the service life of the power battery, causing irreversible damage, and even leading to safety accidents.

[0003] The application of new energy vehicles in high-altitude and cold areas is very limited, especially the charging process. The power battery must be heated first, and charging can only be carried out after the power battery reaches a certain temperature. This will greatly increase the charging time and the charging speed is slower. Summary of the Invention

[0004] The present disclosure provides a DC charging pile and a control method thereof. A power distribution module is added to the DC charging pile. By controlling the power distribution module according to the temperature of the power battery, the power battery can be heated and charged simultaneously, shortening the time required for the entire charging process and significantly improving the charging speed of the power battery at low temperatures. The technical solutions of the present disclosure are as follows:

[0005] According to a first aspect of an embodiment of the present disclosure, a DC charging pile is provided, which includes: a power distribution module, a DC-DC converter module, an energy storage module, an AC-DC converter module, and a charging terminal; wherein,

[0006] The first end of the power distribution module is connected to the energy storage module through the DC-DC module, the second end of the power distribution module is connected to the AC power grid through the AC-DC module, and the third end of the power distribution module is connected to the charging terminal;

[0007] The charging terminal is used to obtain the temperature of the power battery and control the power distribution module according to the temperature, so that the working mode of the power battery is switched among the heating mode, the charging mode, and the heating and charging synchronous mode.

[0008] In one embodiment of the present disclosure, the power distribution module includes: a first switch, a second switch and a third switch; wherein,

[0009] The first end of the first switch serves as the first end of the power distribution module, the second end of the first switch is connected to the first end of the second switch and the first end of the third switch respectively, the second end of the second switch serves as the second end of the power distribution module, and the second end of the third switch serves as the third end of the power distribution module; wherein,

[0010] The charging terminal controls the on and off of the first switch, the second switch, and the third switch to switch the working mode of the power battery among the heating mode, the charging mode, and the heating and charging synchronous mode.

[0011] In one embodiment of the present disclosure, before the charging terminal obtains the temperature of the power battery, it is determined that the charging terminal is connected to the power battery, and then the third switch is controlled to be closed.

[0012] In one embodiment of the present disclosure, the charging terminal, in response to the temperature being less than a first temperature threshold, controls the first switch to be closed, the second switch to be opened, and the third switch to be closed, and obtains the target heating current and target heating frequency according to the temperature, and controls the heating current and heating frequency of the power battery according to the target heating current and the target heating frequency through the DC-DC module to realize the heating mode of the power battery.

[0013] In one embodiment of the present disclosure, the charging terminal controls the first switch to be closed, the second switch to be closed, and the third switch to be closed in response to the temperature being greater than or equal to a first temperature threshold and less than a second temperature threshold, and obtains the target heating current, target heating frequency, and target charging current according to the temperature, and controls the heating current, heating frequency, and charging current of the power battery according to the target heating current, the target heating frequency, and the target charging current through the DC-to-DC module and the AC-to-DC module, so as to realize a synchronous mode of heating and charging the power battery.

[0014] In one embodiment of the present disclosure, the charging terminal, in response to the temperature being greater than or equal to a second temperature threshold, controls the first switch to be opened, the second switch to be closed, and the third switch to be closed, and obtains the target charging current according to the temperature, and controls the charging current of the power battery according to the target charging current through the AC-DC module to realize the charging mode of the power battery.

[0015] In one embodiment of the present disclosure, the DC-DC module includes: a first switch unit, a second switch unit, a first inductor, a second inductor, and a transformer; wherein,

[0016] The first end of the first switch unit is connected to the positive electrode of the energy storage module, the second end of the first switch unit is connected to the negative electrode of the energy storage module, the third end of the first switch unit is connected to the first end of the transformer through the first inductor, and the fourth end of the first switch is connected to the second end of the transformer;

[0017] The first end of the second switch unit is connected to the first end of the power distribution module, the second end of the second switch unit is connected to the common end of the power distribution module, the third end of the second switch unit is connected to the third end of the transformer through the second inductor, and the fourth end of the second switch unit is connected to the fourth end of the transformer.

[0018] In one embodiment of the present disclosure, the first switch unit includes first to fourth switch tubes; wherein,

[0019] The first end of the first switching tube and the first end of the second switching tube are connected to serve as the first end of the first switching unit;

[0020] The second end of the first switch tube is connected to the first end of the third switch tube and serves as the fourth end of the first switch unit;

[0021] The second end of the second switch tube is connected to the first end of the fourth switch tube and serves as the third end of the first switch unit;

[0022] The second end of the third switch tube is connected to the second end of the fourth switch tube and serves as the second end of the first switch unit.

[0023] In one embodiment of the present disclosure, the second switch unit includes fifth to eighth switch tubes; wherein,

[0024] The first end of the fifth switch tube and the first end of the sixth switch tube are connected to serve as the first end of the second switch unit;

[0025] The second end of the fifth switch tube is connected to the first end of the seventh switch tube and serves as the fourth end of the second switch unit;

[0026] The second end of the sixth switch tube is connected to the first end of the eighth switch tube and serves as the third end of the second switch unit;

[0027] The second end of the seventh switch tube is connected to the second end of the eighth switch tube and serves as the second end of the second switch unit.

[0028] In one embodiment of the present disclosure, the DC-DC module further includes: a first capacitor and a second capacitor; wherein,

[0029] A first end of the first capacitor is connected to a first end of the first switch unit, and a second end of the first capacitor is connected to a second end of the first switch unit;

[0030] A first end of the second capacitor is connected to a first end of the second switch unit, and a second end of the second capacitor is connected to a second end of the second switch unit.

[0031] According to a second aspect of the embodiments of the present disclosure, a control method for a DC charging pile based on the embodiment of the first aspect is proposed, including:

[0032] Get the temperature of the power battery;

[0033] The power distribution module is controlled according to the temperature so that the operating mode of the power battery is switched among a heating mode, a charging mode, and a heating and charging synchronous mode.

[0034] In one embodiment of the present disclosure, controlling the power distribution module to switch the operating mode of the power battery among a heating mode, a charging mode, and a heating and charging synchronous mode includes:

[0035] By controlling the on and off of the first switch, the second switch, and the third switch, the operating mode of the power battery is switched among the heating mode, the charging mode, and the heating and charging synchronous mode.

[0036] In one embodiment of the present disclosure, before obtaining the temperature of the power battery, the method further includes:

[0037] If it is determined that the charging terminal is connected to the power battery, the third switch is controlled to be closed.

[0038] In one embodiment of the present disclosure, controlling the on and off of the first switch, the second switch, and the third switch to switch the operating mode of the power battery among the heating mode, the charging mode, and the heating and charging simultaneous mode includes:

[0039] In response to the temperature being less than a first temperature threshold, controlling the first switch to be closed, the second switch to be open, and the third switch to be closed, and obtaining a target heating current and a target heating frequency according to the temperature;

[0040] The DC-DC module controls the heating current and the heating frequency of the power battery according to the target heating current and the target heating frequency, so as to implement the heating mode for the power battery.

[0041] In one embodiment of the present disclosure, controlling the on and off of the first switch, the second switch, and the third switch to switch the operating mode of the power battery among the heating mode, the charging mode, and the heating and charging simultaneous mode includes:

[0042] In response to the temperature being greater than or equal to a first temperature threshold and less than a second temperature threshold, controlling the first switch to be closed, the second switch to be closed, and the third switch to be closed, and obtaining a target heating current, a target heating frequency, and a target charging current according to the temperature;

[0043] The DC-to-DC module and the AC-to-DC module are used to control the heating current, heating frequency and charging current of the power battery according to the target heating current, the target heating frequency and the target charging current, so as to realize a synchronous mode of heating and charging the power battery.

[0044] In one embodiment of the present disclosure, controlling the on and off of the first switch, the second switch, and the third switch to switch the operating mode of the power battery among the heating mode, the charging mode, and the heating and charging simultaneous mode includes:

[0045] In response to the temperature being greater than or equal to a second temperature threshold, controlling the first switch to be open, the second switch to be closed, and the third switch to be closed, and obtaining a target charging current according to the temperature;

[0046] The AC-DC module controls the charging current of the power battery according to the target charging current, so as to realize the charging mode of the power battery.

[0047] The technical solutions provided by the embodiments of the present disclosure bring at least the following beneficial effects:

[0048] According to the embodiment of the present disclosure, the DC charging pile includes: a power distribution module, a DC-DC module, an energy storage module, an AC-DC module and a charging terminal; wherein the first end of the power distribution module is connected to the energy storage module via the DC-DC module, the second end of the power distribution module is connected to the AC power grid via the AC-DC module, and the third end of the power distribution module is connected to the charging terminal; the charging terminal is used to obtain the temperature of the power battery and control the power distribution module according to the temperature so that the working mode of the power battery can be switched between heating mode, charging mode, and heating and charging synchronous mode. Therefore, by adding a power distribution module to the DC charging pile, the charging terminal of the DC charging pile controls the power distribution module according to the temperature of the power battery, so that the power battery can achieve heating and charging synchronous mode, shortening the time required for the entire charging process and greatly improving the charging speed of the power battery at low temperatures.

[0049] It is to be understood that the foregoing general description and the following detailed description are exemplary and explanatory only and are not restrictive of the disclosure. BRIEF DESCRIPTION OF THE DRAWINGS

[0050] The accompanying drawings herein are incorporated into and constitute a part of the specification, illustrate embodiments consistent with the present disclosure, and together with the description are used to explain the principles of the present disclosure, and do not constitute an improper limitation of the present disclosure.

[0051] Figure 1 is a schematic diagram of a DC charging pile according to an embodiment of the present disclosure;

[0052] Figure 2 This is a current waveform diagram when a DC charging pile heats a power battery according to an embodiment of the present disclosure;

[0053] Figure 3 This is a current waveform diagram when a DC charging pile according to an embodiment of the present disclosure simultaneously charges and heats a power battery;

[0054] Figure 4 is a schematic diagram of a DC charging pile according to an embodiment of the present disclosure;

[0055] Figure 5 is a schematic diagram of a DC-DC module according to one embodiment of the present disclosure;

[0056] Figure 6 4 is a flow chart of a control method for a DC charging pile according to an embodiment of the present disclosure. DETAILED DESCRIPTION

[0057] In order to enable ordinary persons in the art to better understand the technical solutions of the present disclosure, the technical solutions in the embodiments of the present disclosure will be clearly and completely described below with reference to the accompanying drawings.

[0058] It should be noted that the terms "first," "second," and the like in the specification and claims of the present disclosure and the above-mentioned drawings are used to distinguish similar objects and are not necessarily used to describe a specific order or precedence. It should be understood that the numbers used in this manner are interchangeable where appropriate so that the embodiments of the present disclosure described herein can be implemented in an order other than those illustrated or described herein. The embodiments described in the following exemplary embodiments do not represent all embodiments consistent with the present disclosure. Instead, they are merely examples of apparatus and methods consistent with certain aspects of the present disclosure as detailed in the appended claims.

[0059] The following describes a DC charging pile and a control method of a DC charging pile according to embodiments of the present disclosure with reference to the accompanying drawings.

[0060] At present, the power batteries of vehicles such as new energy vehicles mainly use lithium batteries. The working characteristics of lithium batteries are significantly affected by their temperature, especially at low temperatures. The electrochemical reaction activity of lithium batteries is reduced, and the charging and discharging performance decays very seriously. In addition, low-temperature charging may cause lithium ion precipitation and accumulation, seriously affecting the service life of the power battery, causing irreversible damage, and even leading to safety accidents.

[0061] The application of new energy vehicles in high-altitude and cold regions is very limited, especially during the charging process. The power battery must be heated first, and charging can only be carried out after the power battery reaches a certain temperature, which greatly increases the charging time. The current mainstream new energy vehicle battery heating method mainly relies on external heating, such as PTC heating or water circulation system heating. The heating speed is relatively slow and the power consumption is also relatively high. Another way to heat the battery is to heat it from the inside. By utilizing the impedance characteristics of the battery at different frequencies, current is applied to the battery to generate heat inside the battery. This method has higher thermal efficiency and faster heating rate. However, this solution cannot achieve simultaneous charging and heating as the battery temperature rises.

[0062] To this end, the present disclosure proposes a DC charging pile, in which a power distribution module is added. The power distribution module is controlled according to the temperature of the power battery, so that the power battery can be heated and charged simultaneously, shortening the time required for the entire charging process and greatly improving the charging speed of the power battery at low temperatures.

[0063] Figure 1 Schematic diagram of a DC charging pile according to an embodiment of the present disclosure.

[0064] like Figure 1 As shown, the DC charging pile of the embodiment of the present disclosure includes: a power distribution module 110, a DC-DC module 120, an energy storage module 130, an AC-DC module 140 and a charging terminal 150.

[0065] The first end of the power distribution module 110 is connected to the energy storage module 130 via the DC-DC converter 120. The second end of the power distribution module 110 is connected to the AC power grid via the AC-DC converter 140. The third end of the power distribution module 110 is connected to the charging terminal 150. The charging terminal 150 is used to obtain the temperature of the power battery and, based on the temperature, control the power distribution module 110 to switch the power battery's operating mode between heating mode, charging mode, or simultaneous heating and charging mode.

[0066] In actual application, when the power battery of the vehicle needs to be charged, the user can connect the charging gun of the DC charging pile to the power battery of the vehicle, that is, connect the power battery to the charging terminal 150 of the DC charging pile.

[0067] After the power battery is connected to the charging terminal 150 of the DC charging pile.

[0068] First, the vehicle's battery manager establishes a communication protocol with the charging terminal 150 of the DC charging pile, and after making charging preparations, it controls the power module to form a power connection circuit between the power battery and the DC charging pile.

[0069] Then, the charging terminal 150 communicates with the battery manager to obtain the temperature of the power battery. When the temperature of the power battery is less than the first temperature threshold, the power battery is not allowed to charge. The battery manager will obtain the target heating current and target heating frequency by looking up the table according to the temperature of the power battery (it should be noted that the relationship between the temperature, target heating current and target heating frequency of the power battery can be obtained through experiments, and a table can be formed for subsequent use), and send it to the charging terminal 150. Based on the target heating current and target heating frequency provided by the battery manager, the charging terminal 150 controls the power distribution module 110 so that the energy storage module 130 is connected to the charging terminal 150 through the DC-DC module 120. At this time, the working mode of the power battery is in the heating mode. Specifically, the heating current of the power battery is controlled by the DC-DC module 120, so that the heating current of the power battery is in a rapidly changing alternating current. At this time, the average value of the current on the power battery side is an alternating heating current of 0, such as Figure 2 As shown, the DC-DC module 120 is used to provide a reciprocating alternating heating current to the power battery. At this time, the power battery is neither charged nor discharged, but the heat generated by the alternating current and the internal resistance of the power battery is used to quickly heat the power battery.

[0070] Next, when the temperature of the power battery rises with heating, such as when it is in the range greater than or equal to the first temperature threshold and less than the second temperature threshold, the rechargeable battery is allowed to be charged at a low rate. The battery manager will obtain the target heating current, target heating frequency and target charging current by looking up the table according to the temperature of the power battery, and send it to the charging terminal 150. The charging terminal 150 controls the power distribution module 110 based on the target heating current, target heating frequency and target charging current provided by the battery manager, so that the energy storage module 130 is connected to the charging terminal 150 through the DC-DC module 120. At the same time, the AC power grid is also connected to the charging terminal 150 through the AC-DC module 140. At this time, the working mode of the power battery is in the charging and heating synchronization mode. Specifically, while the DC-DC module 120 keeps working, power conversion is performed from the AC power grid through the AC-DC module 140 to add DC charging current to the power battery. At this time, the current of the power battery is expressed as an alternating current superimposed with a DC charging current component, such as Figure 3 As shown, the DC-DC module 120 is used to provide a reciprocating alternating heating current to the power battery, while the AC-DC module converts the AC power of the AC grid into DC power to charge the power battery. In this way, low-rate charging can be achieved while heating.

[0071] Finally, when the power battery's temperature is greater than or equal to the second temperature threshold, the power battery allows for higher-rate charging. The battery manager obtains the target charging current based on the power battery's temperature through a table lookup and sends it to the charging terminal 150. Based on the target charging current provided by the battery manager, the charging terminal 150 controls the power distribution module 110 to connect the AC grid to the charging terminal 150 via the AC-DC converter 140. At this point, the power battery operates in charging mode, meaning the AC-DC converter 140 supplies the full charging current to the power battery for high-rate charging.

[0072] It should be noted that the charging terminal 150 can obtain the capacity of the AC power grid. If the charging power requested by the battery manager is greater than the capacity of the AC power grid, this indicates that the AC power grid is insufficient. The power distribution module 110 connects the energy storage module 130 to the charging terminal 150, and the AC power grid is also connected to the charging terminal 150 via the AC-DC module 140. The AC power grid and the energy storage module 130 jointly charge the power battery. The charging terminal 150 also obtains the remaining charge of the energy storage module 130. If the remaining charge is less than a remaining charge threshold, it indicates that the capacity of the energy storage module 130 is low and energy needs to be replenished. At this time, the power distribution module 110 is controlled to connect the energy storage module 130 to the charging terminal 150 via the DC-DC module 120, and the AC power grid is also connected to the charging terminal 150 via the AC-DC module 140. In this way, the AC power grid simultaneously charges the energy storage module 130 and the power battery.

[0073] The DC charging pile disclosed in the present invention is mainly composed of an AC-DC module 140, a power distribution module 110, a DC-DC module 120, an energy storage module 130 and a charging terminal 150. Among them, the AC-DC module 140 is used to convert the AC power of the AC power grid into DC power to charge the power battery or the energy storage module 130; the DC-DC module 120 is used to provide a cyclic alternating heating current to the power battery, or to use the DC power of the energy storage module 130 as a supplement to charge the power battery; the power distribution module 110 is used to switch between heating mode, charging mode and heating and charging synchronous mode according to different needs.

[0074] Therefore, the DC charging pile disclosed in the present invention controls the power distribution module 110 to enable the power battery to achieve a simultaneous heating and charging mode, shortening the time required for the entire charging process and greatly improving the charging speed of the power battery at low temperatures.

[0075] In order to make those skilled in the art understand the present disclosure more clearly, the following Figure 4 The DC charging pile disclosed in the present invention is described.

[0076] like Figure 4 As shown, the power distribution module 110 includes a first switch K1, a second switch K2, and a third switch K3. The first end of the first switch K1 serves as the first end of the power distribution module 110, and the second end of the first switch K1 is connected to the first end of the second switch K2 and the first end of the third switch K3, respectively. The second end of the second switch K2 serves as the second end of the power distribution module 110, and the second end of the third switch K3 serves as the third end of the power distribution module 110. The charging terminal 150 switches the operating mode of the power battery among a heating mode, a charging mode, and a heating and charging simultaneous mode by controlling the on and off of the first switch K1, the second switch K2, and the third switch K3.

[0077] That is, the charging terminal 150 can switch between the heating mode, the charging mode, and the heating and charging synchronous mode under different requirements by controlling the on and off of the first switch K1 , the second switch K2 , and the third switch K3 .

[0078] In one embodiment of the present disclosure, before the charging terminal 150 obtains the temperature of the power battery, it is determined that the charging terminal 150 is connected to the power battery, and the third switch K3 is controlled to be closed.

[0079] That is, after the power battery is connected to the charging terminal 150 of the DC charging pile, the vehicle's battery manager establishes a communication protocol with the DC charging pile and is ready for charging, the charging terminal 150 controls the third switch K3 to close, forming a power connection circuit between the power battery and the DC charging pile.

[0080] In one embodiment of the present disclosure, the charging terminal 150, in response to the temperature being less than a first temperature threshold, controls the first switch K1 to be closed, the second switch K2 to be disconnected, and the third switch K3 to be closed, and obtains the target heating current and target heating frequency according to the temperature, and controls the heating current and heating frequency of the power battery according to the target heating current and target heating frequency through the DC-DC module 120 to realize a heating mode for the power battery.

[0081] That is to say, the charging terminal 150 communicates with the battery manager to obtain the temperature of the power battery. When the temperature of the power battery is lower than the first temperature threshold, the power battery is not allowed to charge. The battery manager will obtain the target heating current and target heating frequency by looking up the table according to the temperature of the power battery, and send it to the charging terminal 150. The charging terminal 150 controls the first switch K1 to close, the second switch K2 to open, and the third switch K3 to close according to the target heating current and target heating frequency provided by the battery manager, so that the energy storage module 130 is connected to the charging terminal 150 through the DC-DC module 120. At this time, the working mode of the power battery is in the heating mode. Specifically, the current on the power battery side is controlled by the DC-DC module 120, so that the current of the power battery is in a rapidly changing alternating current. At this time, the average value of the current on the power battery side is an alternating heating current of 0, such as Figure 2 At this time, the power battery is neither charged nor discharged, but the heat generated by the alternating current and the internal resistance of the power battery is used to heat the power battery quickly.

[0082] In one embodiment of the present disclosure, the charging terminal 150 controls the first switch K1 to be closed, the second switch K2 to be closed, and the third switch K3 to be closed in response to the temperature being greater than or equal to the first temperature threshold and less than the second temperature threshold, and obtains the target heating current, target heating frequency, and target charging current according to the temperature, and controls the heating current, heating frequency, and charging current of the power battery according to the target heating current, target heating frequency, and target charging current through the DC-to-DC module 120 and the AC-to-DC module 140, so as to realize a synchronous mode of heating and charging the power battery.

[0083] That is to say, when the temperature of the power battery rises with heating and is in a range greater than or equal to the first temperature threshold and less than the second temperature threshold, the rechargeable battery is allowed to be charged at a low rate. The battery manager will obtain the target heating current, target heating frequency and target charging current by looking up the table according to the temperature of the power battery, and send it to the charging terminal 150. The charging terminal 150 controls the second switch K2 to close according to the target heating current, target heating frequency and target charging current provided by the battery manager, so that the AC power grid is also connected to the charging terminal 150 through the AC to DC module 140. At the same time, the first switch K1 remains closed, so that the energy storage module 130 is connected to the charging terminal 150 through the DC to DC module 120. At this time, the working mode of the power battery is in the charging and heating synchronization mode. Specifically, while the DC to DC module 120 remains working, power conversion is performed from the AC power grid through the AC to DC module 140 to add DC charging current to the power battery. At this time, the current of the power battery appears as an alternating current with a superimposed DC charging current component, such as Figure 3As shown. This allows for simultaneous heating and low-rate charging.

[0084] In one embodiment of the present disclosure, the charging terminal 150 controls the first switch K1 to be opened, the second switch K2 to be closed, and the third switch K3 to be closed in response to the temperature being greater than or equal to the second temperature threshold, and obtains the target charging current according to the temperature, and controls the charging current of the power battery according to the target charging current through the AC-DC module 140 to realize the charging synchronization mode of the power battery.

[0085] That is, when the power battery's temperature is greater than or equal to the second temperature threshold, the power battery allows for higher-rate charging. The battery manager obtains the target charging current based on the power battery's temperature by looking up a table and sends it to the charging terminal 150. Based on the target charging current provided by the battery manager, the charging terminal 150 controls the first switch K1 to open, the second switch K2 to close, and the third switch K3 to close. This disconnects the energy storage module 130 from the charging terminal 150, and the AC grid is connected to the charging terminal 150 via the AC-DC module 140. At this point, the power battery operates in charging mode, meaning the AC-DC module 140 supplies the entire charging current to the power battery, enabling high-rate charging.

[0086] It should be noted that the charging terminal 150 can obtain the capacity of the AC power grid. If the charging power requested by the battery manager is greater than the capacity of the AC power grid, the AC power grid is insufficient. The power distribution module 110 connects the energy storage module 130 to the charging terminal 150, and the AC power grid is also connected to the charging terminal 150 via the AC-DC module 140. The AC power grid and the energy storage module 130 jointly charge the power battery. The charging terminal 150 also obtains the remaining charge of the energy storage module 130. If the remaining charge is less than the remaining charge threshold, it indicates that the capacity of the energy storage module 130 is low and energy needs to be replenished. At this time, the power distribution module 110 is controlled to connect the energy storage module 130 to the charging terminal 150 via the DC-DC module 120, and the AC power grid is also connected to the charging terminal 150 via the AC-DC module 140. In this way, the AC power grid simultaneously charges the energy storage module 130 and the power battery.

[0087] Therefore, when the vehicle's power battery temperature is low and needs to be charged quickly, the DC charging pile is first used to provide alternating current excitation, so that the vehicle's power battery can be quickly self-heated. As the power battery temperature rises, the charging current excitation is gradually increased, so that the vehicle's power battery is charged while rapidly heating up, shortening the time required for the entire charging process.

[0088] In order to make those skilled in the art more clearly understand the DC to DC module 120 of the present disclosure, the following is a detailed description of the DC to DC module 120 in combination with the present disclosure. Figure 5 The DC-DC module 120 will be described.

[0089] like Figure 5 As shown, the DC-DC module 120 includes: a first switch unit 121, a second switch unit 122, a first inductor L1, a second inductor L2, and a transformer. The first end of the first switch unit 121 is connected to the positive electrode of the energy storage module 130, the second end of the first switch unit 121 is connected to the negative electrode of the energy storage module 130, the third end of the first switch unit 121 is connected to the first end of the transformer via the first inductor L1, and the fourth end of the first switch K1 is connected to the second end of the transformer; the first end of the second switch unit 122 is connected to the first end of the power distribution module 110, the second end of the second switch unit 122 is connected to the common end of the power distribution module 110 (the common end here is a shared neutral end, connected to the negative end of the charging terminal 150), the third end of the second switch unit 122 is connected to the third end of the transformer via the second inductor L2, and the fourth end of the second switch unit 122 is connected to the fourth end of the transformer.

[0090] like Figure 5 As shown, the first switch unit 121 includes first to fourth switch tubes; wherein, the first end of the first switch tube is connected to the first end of the second switch tube K2 and serves as the first end of the first switch unit 121; the second end of the first switch tube is connected to the first end of the third switch tube K3 and serves as the fourth end of the first switch unit 121; the second end of the second switch tube K2 and the first end of the fourth switch tube are connected to serve as the third end of the first switch unit 121; and the second end of the third switch tube K3 and the second end of the fourth switch tube are connected to serve as the second end of the first switch unit 121.

[0091] The first switch K1 may be IGBT1, the second switch K2 may be IGBT2, the third switch K3 may be IGBT3, and the fourth switch may be IGBT4.

[0092] like Figure 5 As shown, the second switch unit 122 includes a fifth switch tube to an eighth switch tube; wherein, the first end of the fifth switch tube is connected to the first end of the sixth switch tube and serves as the first end of the second switch unit 122; the second end of the fifth switch tube is connected to the first end of the seventh switch tube and serves as the fourth end of the second switch unit 122; the second end of the sixth switch tube is connected to the first end of the eighth switch tube and serves as the third end of the second switch unit 122; the second end of the seventh switch tube is connected to the second end of the eighth switch tube and serves as the second end of the second switch unit 122.

[0093] The fifth switch may be IGBT5, the sixth switch may be IGBT6, the seventh switch may be IGBT7, and the eighth switch may be IGBT8.

[0094] like Figure 5 As shown, the DC-DC module 120 further includes a first capacitor C1 and a second capacitor C2. The first end of the first capacitor C1 is connected to the first end of the first switch unit 121, and the second end of the first capacitor C1 is connected to the second end of the first switch unit 121. The first end of the second capacitor C2 is connected to the first end of the second switch unit 122, and the second end of the second capacitor C2 is connected to the second end of the second switch unit 122. The first capacitor C1 and the second capacitor C2 are used for filtering.

[0095] In summary, the DC charging pile of the embodiment of the present disclosure is composed of a power distribution module, a DC-DC module, an energy storage module, an AC-DC module and a charging terminal, wherein the first end of the power distribution module is connected to the energy storage module through the DC-DC module, the second end of the power distribution module is connected to the AC power grid through the AC-DC module, and the third end of the power distribution module is connected to the charging terminal; the charging terminal is used to obtain the temperature of the power battery and control the power distribution module according to the temperature so that the working mode of the power battery can be switched among the heating mode, the charging mode, and the heating and charging synchronous mode. Therefore, by adding a power distribution module to the DC charging pile, the charging terminal of the DC charging pile controls the power distribution module according to the temperature of the power battery, so that the power battery can realize the heating and charging synchronous mode, shortening the time required for the entire charging process and greatly improving the charging speed of the power battery at low temperatures.

[0096] Figure 6 4 is a flow chart of a control method for a DC charging pile according to an embodiment of the present disclosure.

[0097] like Figure 6 As shown, the control method of the DC charging pile in the embodiment of the present disclosure includes:

[0098] S601: Obtain the temperature of the power battery.

[0099] S602 : Control the power distribution module according to the temperature so that the working mode of the power battery is switched among a heating mode, a charging mode, and a heating and charging synchronous mode.

[0100] In one embodiment of the present disclosure, controlling the power distribution module to switch the operating mode of the power battery among a heating mode, a charging mode, and a heating and charging synchronous mode includes:

[0101] By controlling the on and off of the first switch, the second switch and the third switch, the working mode of the power battery is switched among the heating mode, the charging mode and the heating and charging synchronous mode.

[0102] In one embodiment of the present disclosure, before obtaining the temperature of the power battery, the method further includes:

[0103] If it is determined that the charging terminal is connected to the power battery, the third switch is controlled to be closed.

[0104] In one embodiment of the present disclosure, the operation mode of the power battery is switched among a heating mode, a charging mode, and a heating and charging simultaneous mode by controlling the on and off of the first switch, the second switch, and the third switch, including:

[0105] In response to the temperature being less than a first temperature threshold, controlling the first switch to be closed, the second switch to be opened, and the third switch to be closed, and obtaining a target heating current and a target heating frequency according to the temperature;

[0106] Through the DC-DC module, the heating current and heating frequency of the power battery are controlled according to the target heating current and target heating frequency to realize the heating mode of the power battery.

[0107] In one embodiment of the present disclosure, the operation mode of the power battery is switched among a heating mode, a charging mode, and a heating and charging simultaneous mode by controlling the on and off of the first switch, the second switch, and the third switch, including:

[0108] In response to the temperature being greater than or equal to a first temperature threshold and less than a second temperature threshold, controlling the first switch to be closed, the second switch to be closed, and the third switch to be closed, and obtaining a target heating current, a target heating frequency, and a target charging current according to the temperature;

[0109] Through the DC-DC module and the AC-DC module, the heating current, heating frequency and charging current of the power battery are controlled accordingly according to the target heating current, target heating frequency and target charging current, so as to realize the synchronous mode of heating and charging the power battery.

[0110] In one embodiment of the present disclosure, the operation mode of the power battery is switched among a heating mode, a charging mode, and a heating and charging simultaneous mode by controlling the on and off of the first switch, the second switch, and the third switch, including:

[0111] In response to the temperature being greater than or equal to a second temperature threshold, controlling the first switch to be open, the second switch to be closed, and the third switch to be closed, and obtaining a target charging current according to the temperature;

[0112] Through the AC to DC module, the charging current of the power battery is controlled according to the target charging current to realize the charging mode of the power battery.

[0113] It should be noted that for details not disclosed in the control method of the DC charging pile in the embodiment of the present disclosure, please refer to the details disclosed in the DC charging pile in the embodiment of the present disclosure, and the details will not be repeated here.

[0114] It should be noted that the control method for a DC charging pile in the disclosed embodiment obtains the temperature of the power battery and, based on the temperature, controls the power distribution module to switch the power battery's operating mode between heating mode, charging mode, and simultaneous heating and charging mode. Thus, by controlling the power distribution module based on the power battery's temperature, the power battery achieves simultaneous heating and charging mode, shortening the entire charging process and significantly improving the power battery's charging speed at low temperatures.

[0115] Other embodiments of the present disclosure will readily occur to those skilled in the art after considering the specification and practicing the invention disclosed herein. This disclosure is intended to cover any variations, uses, or adaptations of the present disclosure that follow the general principles of the present disclosure and include common knowledge or customary techniques in the art not disclosed herein. The description and examples are to be considered as exemplary only, with the true scope and spirit of the present disclosure being indicated by the following claims.

[0116] It should be understood that the present disclosure is not limited to the exact structures that have been described above and shown in the drawings, and that various modifications and changes can be made without departing from the scope thereof. The scope of the present disclosure is limited only by the appended claims.

Claims

1. A DC charging pile, characterized in that: include: Power distribution module, DC-DC module, energy storage module, AC-DC module and charging terminal; among them, The first end of the power distribution module is connected to the energy storage module through the DC-DC module, the second end of the power distribution module is connected to the AC power grid through the AC-DC module, and the third end of the power distribution module is connected to the charging terminal; The charging terminal is used to obtain the temperature of the power battery and control the power distribution module according to the temperature to switch the operating mode of the power battery among a heating mode, a charging mode, and a heating and charging synchronous mode; The power distribution module includes: a first switch, a second switch and a third switch; The first end of the first switch serves as the first end of the power distribution module, the second end of the first switch is connected to the first end of the second switch and the first end of the third switch respectively, the second end of the second switch serves as the second end of the power distribution module, and the second end of the third switch serves as the third end of the power distribution module; The charging terminal switches the operating mode of the power battery among the heating mode, the charging mode, and the heating and charging synchronous mode by controlling the on and off of the first switch, the second switch, and the third switch; The charging terminal, in response to the temperature being less than a first temperature threshold, controls the first switch to be closed, the second switch to be opened, and the third switch to be closed, and obtains a target heating current and a target heating frequency according to the temperature, and controls the heating current and heating frequency of the power battery according to the target heating current and the target heating frequency through the DC-DC module, so as to implement the heating mode for the power battery.

2. The DC charging pile according to claim 1, characterized in that: in, Before the charging terminal obtains the temperature of the power battery, it is determined that the charging terminal is connected to the power battery, and then the third switch is controlled to be closed.

3. The DC charging pile according to claim 2, characterized in that: in, The charging terminal, in response to the temperature being greater than or equal to a first temperature threshold and less than a second temperature threshold, controls the first switch to be closed, the second switch to be closed, and the third switch to be closed, and obtains a target heating current, a target heating frequency, and a target charging current according to the temperature, and controls the heating current, heating frequency, and charging current of the power battery accordingly through the DC-to-DC module and the AC-to-DC module according to the target heating current, the target heating frequency, and the target charging current, so as to realize a synchronous mode of heating and charging the power battery.

4. The DC charging pile according to claim 2, characterized in that: in, The charging terminal, in response to the temperature being greater than or equal to a second temperature threshold, controls the first switch to be opened, the second switch to be closed, and the third switch to be closed, obtains a target charging current based on the temperature, and controls the charging current of the power battery according to the target charging current through the AC-DC module, so as to implement a charging mode for the power battery.

5. The DC charging pile according to claim 1, characterized in that: The DC-DC module includes: a first switch unit, a second switch unit, a first inductor, a second inductor and a transformer; wherein, The first end of the first switch unit is connected to the positive electrode of the energy storage module, the second end of the first switch unit is connected to the negative electrode of the energy storage module, the third end of the first switch unit is connected to the first end of the transformer through the first inductor, and the fourth end of the first switch is connected to the second end of the transformer; The first end of the second switch unit is connected to the first end of the power distribution module, the second switch unit is connected to the common end of the power distribution module, the third end of the second switch unit is connected to the third end of the transformer through the second inductor, and the fourth end of the second switch unit is connected to the fourth end of the transformer.

6. The DC charging pile according to claim 5, characterized in that: The first switch unit includes first to fourth switch tubes; wherein, The first end of the first switching tube and the first end of the second switching tube are connected to serve as the first end of the first switching unit; The second end of the first switch tube is connected to the first end of the third switch tube and serves as the fourth end of the first switch unit; The second end of the second switch tube is connected to the first end of the fourth switch tube and serves as the third end of the first switch unit; The second end of the third switch tube is connected to the second end of the fourth switch tube and serves as the second end of the first switch unit.

7. The DC charging pile according to claim 5, characterized in that: The second switch unit includes the fifth to eighth switch tubes; wherein, The first end of the fifth switch tube and the first end of the sixth switch tube are connected to serve as the first end of the second switch unit; The second end of the fifth switch tube is connected to the first end of the seventh switch tube and serves as the fourth end of the second switch unit; The second end of the sixth switch tube is connected to the first end of the eighth switch tube and serves as the third end of the second switch unit; The second end of the seventh switch tube is connected to the second end of the eighth switch tube and serves as the second end of the second switch unit.

8. The DC charging pile according to claim 5, characterized in that: The DC-DC module further includes: a first capacitor and a second capacitor; wherein, A first end of the first capacitor is connected to a first end of the first switch unit, and a second end of the first capacitor is connected to a second end of the first switch unit; A first end of the second capacitor is connected to a first end of the second switch unit, and a second end of the second capacitor is connected to a second end of the second switch unit.

9. A control method for a DC charging pile according to any one of claims 1 to 8, characterized in that: include: Get the temperature of the power battery; The power distribution module is controlled according to the temperature so that the operating mode of the power battery is switched among a heating mode, a charging mode, and a heating and charging synchronous mode.

10. The control method according to claim 9, characterized in that: The controlling of the power distribution module to switch the operating mode of the power battery among a heating mode, a charging mode, and a heating and charging synchronous mode includes: By controlling the on and off of the first switch, the second switch, and the third switch, the operating mode of the power battery is switched among the heating mode, the charging mode, and the heating and charging synchronous mode.

11. The control method according to claim 10, characterized in that: Before obtaining the temperature of the power battery, the method further includes: If it is determined that the charging terminal is connected to the power battery, the third switch is controlled to be closed.

12. The control method according to claim 11, characterized in that: The switching of the operating mode of the power battery among the heating mode, the charging mode, and the heating and charging synchronous mode by controlling the on and off of the first switch, the second switch, and the third switch includes: In response to the temperature being less than a first temperature threshold, controlling the first switch to be closed, the second switch to be open, and the third switch to be closed, and obtaining a target heating current and a target heating frequency according to the temperature; The DC-DC module controls the heating current and the heating frequency of the power battery according to the target heating current and the target heating frequency, so as to implement the heating mode for the power battery.

13. The control method according to claim 11, characterized in that: The switching of the operating mode of the power battery among the heating mode, the charging mode, and the heating and charging synchronous mode by controlling the on and off of the first switch, the second switch, and the third switch includes: In response to the temperature being greater than or equal to a first temperature threshold and less than a second temperature threshold, controlling the first switch to be closed, the second switch to be closed, and the third switch to be closed, and obtaining a target heating current, a target heating frequency, and a target charging current according to the temperature; The DC-to-DC module and the AC-to-DC module are used to control the heating current, heating frequency and charging current of the power battery according to the target heating current, the target heating frequency and the target charging current, so as to realize a synchronous mode of heating and charging the power battery.

14. The control method according to claim 11, characterized in that: The switching of the operating mode of the power battery among the heating mode, the charging mode, and the heating and charging synchronous mode by controlling the on and off of the first switch, the second switch, and the third switch includes: In response to the temperature being greater than or equal to a second temperature threshold, controlling the first switch to be open, the second switch to be closed, and the third switch to be closed, and obtaining a target charging current according to the temperature; The AC-DC module controls the charging current of the power battery according to the target charging current, so as to realize the charging mode of the power battery.

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