Charging pile

Abstract

The utility model relates to the technical field of charging piles, in particular to a charging pile. The charging pile comprises a switching circuit, an AC / DC circuit and an EMC filter circuit, the switching circuit is configured to be electrically connected with a power grid and is used for working in an off state when the charging pile is in a standby state and working in an on state when the charging pile is in a charging state, and the AC / DC circuit is used for converting alternating current of the power grid into direct current when the switching circuit works in the on state; the EMC filter circuit is electrically connected with the switching circuit and the AC / DC circuit, and is used for filtering interference signals from a power grid to the AC / DC circuit. Therefore, the switching circuit is arranged between the power grid and the EMC filter circuit, and the switching circuit is in an off state when the charging pile is in a standby state, so that the EMC filter circuit can be prevented from absorbing energy of the power grid to generate reactive power, and impact on the power grid can be avoided.

Description

Technical Field

[0001] This utility model relates to the field of charging pile technology, and specifically to a charging pile. Background Technology

[0002] In current charging piles, an EMC filter circuit is usually installed between the power grid and the AC / DC circuit to filter out interference signals transmitted from the power grid to the AC / DC circuit. However, since the EMC filter circuit is usually built using components such as capacitors or inductors, even when the charging pile is in standby mode, the EMC filter circuit still absorbs energy from the power grid, thereby generating reactive power. Reactive power can easily cause impact on the power grid. Utility Model Content

[0003] One objective of this embodiment is to provide a charging pile to solve the technical problem of reactive power generated by charging piles during standby in related technologies.

[0004] This utility model embodiment provides a charging pile, including:

[0005] A switching circuit is configured to be electrically connected to the power grid and to operate in an open state when the charging pile is in a standby state and in an on state when the charging pile is in a charging state.

[0006] An AC / DC circuit is used to convert the alternating current (AC) of the power grid into direct current (DC) when the switching circuit is in the on state.

[0007] The EMC filter circuit is electrically connected to both the switching circuit and the AC / DC circuit, and is used to filter out interference signals from the power grid to the AC / DC circuit.

[0008] Optionally, the switching circuit includes:

[0009] A relay assembly is configured to be electrically connected to the power grid and the EMC filter circuit respectively, for making or breaking the electrical connection between the power grid and the EMC filter circuit;

[0010] A relay protection circuit is configured to be electrically connected to the power grid and the relay assembly respectively, for protecting the relay assembly from the surge voltage and lightning current of the power grid.

[0011] Optionally, the relay assembly includes:

[0012] Control circuit, used to output control signals;

[0013] The relay module is configured to be electrically connected to the power grid, the relay protection circuit, and the EMC filter circuit, respectively.

[0014] The drive module is electrically connected to the control circuit and the relay module respectively, and is used to drive the relay module to work in the on state or the off state in response to the control signal. When the relay module works in the on state, the power grid is connected to the EMC filter circuit. When the relay module works in the off state, the power grid is disconnected from the EMC filter circuit.

[0015] Optionally, the relay module includes:

[0016] The first relay is configured to be electrically connected to the first phase line of the power grid, the relay protection circuit and the EMC filter circuit respectively.

[0017] The second relay is configured to be electrically connected to the second phase line of the power grid, the relay protection circuit, and the EMC filter circuit, respectively.

[0018] The third relay is configured to be electrically connected to the third phase line of the power grid, the relay protection circuit, and the EMC filter circuit, respectively.

[0019] Optionally, the drive module includes:

[0020] The first drive unit is electrically connected to the control circuit and the first relay, respectively;

[0021] The second drive unit is electrically connected to the control circuit and the second relay, respectively;

[0022] The third drive unit is electrically connected to both the control circuit and the third relay.

[0023] Optionally, the relay protection circuit includes a first resistor, a second resistor, a third resistor, a fourth resistor, a fifth resistor, a sixth resistor, and a switching transistor;

[0024] The first end of the first resistor, the first end of the second resistor, and the first end of the third resistor are electrically connected to the first phase line of the power grid. The second end of the first resistor, the first end of the fourth resistor, and the first end of the fifth resistor are electrically connected to the second phase line of the power grid. The second end of the second resistor, the second end of the fourth resistor, and the first end of the sixth resistor are electrically connected. The second end of the third resistor, the second end of the fifth resistor, and the second end of the sixth resistor are electrically connected to the first end of the switching transistor. The second end of the switching transistor is grounded.

[0025] Optionally, the EMC filtering circuit includes:

[0026] The first capacitor bank is configured to be electrically connected to the power grid;

[0027] The first common-mode inductor is configured to be electrically connected to the first capacitor bank and the power grid, respectively.

[0028] The second capacitor bank is configured to be electrically connected to the first common-mode inductor and the AC / DC circuit, respectively.

[0029] Optionally, the EMC filtering circuit further includes:

[0030] The second common-mode inductor is configured to be electrically connected to the first common-mode inductor and the second capacitor bank, respectively.

[0031] The third capacitor bank is configured to be electrically connected to the second common-mode inductor and the AC / DC circuit, respectively.

[0032] Optionally, a fuse circuit may also be included;

[0033] The fuse circuit is configured to be electrically connected to both the power grid and the switching circuit.

[0034] Optionally, the fuse circuit includes:

[0035] A first fuse, wherein a first end of the first fuse is configured to be electrically connected to a first phase line of the power grid, and a second end of the first fuse is electrically connected to the switching circuit;

[0036] A second fuse, the first end of which is configured to be electrically connected to the second phase line of the power grid, and the second end of which is electrically connected to the switching circuit;

[0037] A third fuse, the first end of which is configured to be electrically connected to the third phase line of the power grid, and the second end of which is electrically connected to the switching circuit.

[0038] Compared with existing technologies, this embodiment of the invention provides a charging pile, which includes a switching circuit, an AC / DC circuit, and an EMC filter circuit. The switching circuit is configured to be electrically connected to the power grid, operating in an off state when the charging pile is in standby mode and in a conducting state when the charging pile is charging. The AC / DC circuit converts the AC power from the power grid into DC power when the switching circuit is in the conducting state. The EMC filter circuit is electrically connected to both the switching circuit and the AC / DC circuit, filtering out interference signals from the power grid to the AC / DC circuit. Therefore, by setting a switching circuit between the power grid and the EMC filter circuit, which is in an off state when the charging pile is in standby mode, this embodiment avoids the EMC filter circuit absorbing energy from the power grid and generating reactive power, thereby preventing impact on the power grid. Attached Figure Description

[0039] To more clearly illustrate the technical solutions of the embodiments of this utility model, the drawings used in the description of the embodiments of this utility model will be briefly introduced below. Obviously, the drawings described below are only some embodiments of this utility model. For those skilled in the art, other drawings can be obtained based on these drawings without creative effort.

[0040] Figure 1 This is a schematic diagram of an application scenario for a charging pile provided by an embodiment of the present utility model;

[0041] Figure 2 This is a schematic diagram of the structure of a charging pile provided in an embodiment of the present utility model;

[0042] Figure 3 This is a schematic diagram of the structure of a charging pile according to another embodiment of the present invention;

[0043] Figure 4 This is a schematic diagram of an input filtering and voltage conversion circuit provided in an embodiment of the present invention;

[0044] Figure 5 A schematic diagram of the structure of an input filtering and voltage conversion circuit provided for another embodiment of this utility model;

[0045] Figure 6 A schematic diagram of an input filtering and voltage conversion circuit provided in another embodiment of this utility model;

[0046] Figure 7 A schematic diagram of the circuit structure of an input filtering and voltage conversion circuit provided for an embodiment of this utility model;

[0047] Figure 8 A schematic diagram of the circuit structure of an input filtering and voltage conversion circuit provided for another embodiment of this utility model;

[0048] Figure 9 This is a schematic diagram of the structure of a charging pile provided in another embodiment of the present utility model. Detailed Implementation

[0049] To facilitate understanding of this utility model, a more detailed description is provided below with reference to the accompanying drawings and specific embodiments. It should be noted that when an element is described as "connected" to another element, it can be directly connected to the other element, or there may be one or more intervening elements. Furthermore, the terms "first," "second," etc., are used for descriptive purposes only and should not be construed as indicating or implying relative importance.

[0050] Unless otherwise defined, all technical and scientific terms used in this specification have the same meaning as commonly understood by one of ordinary skill in the art to which this invention pertains. The terminology used in this specification is for the purpose of describing particular embodiments only and is not intended to limit the scope of the invention. The term "and / or" as used in this specification includes any and all combinations of one or more of the associated listed items.

[0051] Please see Figure 1 , Figure 1 This utility model provides an application scenario diagram of a charging pile, as shown in the embodiment. Figure 1 As shown, the application scenario includes charging pile 100, power grid 200, and electric vehicle 300.

[0052] The power grid 200 is a power network that transmits mains electricity to the charging pile 100 via transmission lines to supply power to the electric vehicle 300. The mains electricity is industrial frequency alternating current, which is typically characterized by voltage, current, and frequency. Generally, the mains electricity transmitted from the power grid 200 to the charging pile 100 is three-phase alternating current.

[0053] Charging pile 100 is a device used to charge electric vehicle 300 to replenish its power. Its working principle is to receive electrical energy from the power grid 200 and then transmit the energy to electric vehicle 300 through a charging cable to charge it. Charging pile 100 can be any type of charging pile that supports AC charging, such as DC charging piles, AC charging piles, or AC / DC integrated charging piles.

[0054] The DC charging station uses direct current (DC) to charge the power battery of electric vehicle 300; this charging method is also known as "fast charging." The DC charging station is electrically connected to the power grid 200, receiving three-phase 380V AC power from the grid and converting it to DC. This DC power is then delivered to the power battery of electric vehicle 300 through a standard DC charging plug and socket, thus achieving DC charging. The power supply characteristics of the DC charging station itself allow it to output sufficient charging power, with a wide range of voltage and current adjustment, enabling rapid charging. The DC charging station also functions as a charger, capable of monitoring and controlling the operating status of the battery being charged in real time, and can also measure the amount of electricity charged.

[0055] AC charging stations typically use single or dual 220VAC / 380VAC AC output interfaces to provide power to electric vehicles (EVs) 300, enabling them to charge their batteries using onboard chargers. This charging method is also known as "slow charging." The output power of an AC charging station is usually 5kW (220VAC) / 20kW (380VAC), but the actual charging power is limited by the onboard charger; generally, the onboard charging power of small electric vehicles is between 2 and 3kW. The onboard charger of the EV 300 converts AC power into DC power through filtering and rectification, then stores the DC power in the EV 300's battery, thus charging the EV 300. This charging method is mainly used in small pure electric vehicles.

[0056] The input voltage of an AC / DC integrated charging pile is generally three-phase four-wire 380VAC±15% at a frequency of 50Hz. The charging pile includes a DC output port and an AC output port. The DC output port outputs adjustable DC power to charge the power battery of the electric vehicle 300, with a charging power typically ranging from 10 to 40kW. The AC output port outputs 220VAC (5kW) / 380VAC (20kW) AC power to provide charging power for the on-board charger of the electric vehicle 300. The AC / DC integrated charging pile can provide conventional charging through the AC output port and fast charging through the DC output port. During peak charging hours in the daytime, fast charging is used; at night when there are fewer users, conventional charging can be used for slower charging. The AC / DC integrated charging pile can achieve simultaneous AC and DC charging and interlocked charging. Its modular design facilitates maintenance.

[0057] In some embodiments, the charging pile 100 is configured with one or more charging guns. The charging guns are interface devices connecting the charging pile and the electric vehicle 300, primarily used to charge the electric vehicle 300 by transmitting electrical energy. The charging gun typically has a plug and a connecting cable, one end of which connects to the charging pile, and the other end is inserted into the charging port of the electric vehicle 300. Depending on different charging requirements and technical standards, charging guns can be categorized into fast-charging charging guns and slow-charging charging guns.

[0058] Fast charging guns, also known as DC fast charging guns, are typically used at fast charging stations. They have a large power output and can quickly charge the vehicle's power battery.

[0059] Slow charging guns, also known as AC charging guns, are typically used in home charging stations, commercial charging stations, and public charging stations. They have lower power and are suitable for charging with ordinary household power supplies, resulting in a relatively slow charging speed.

[0060] Electric vehicle 300 can receive AC or DC power from charging pile 100. When electric vehicle 300 receives DC power, it can store the DC power in its power battery to charge it. When electric vehicle 300 receives AC power, it can perform voltage conversion, filtering, and rectification to obtain DC power, which is then stored in its power battery to charge it. Electric vehicle 300 includes any vehicle that can be driven by electricity, including but not limited to pure electric vehicles, hybrid electric vehicles, and fuel cell vehicles.

[0061] In some embodiments, please refer to Figure 2 The charging pile 100 includes an input filtering and voltage conversion circuit 10, a DC / DC circuit 20, an output filtering circuit 30, an auxiliary power supply 40, a charging control module 50, a metering module 60, and a communication module 70.

[0062] The input filtering and voltage conversion circuit 10 is electrically connected to the power grid 200. On the one hand, the input filtering and voltage conversion circuit 10 can filter out high-frequency interference signals, thereby reducing conducted interference. On the other hand, the input filtering and voltage conversion circuit 10 can convert the AC power from the power grid 200 into DC power. The input filtering and voltage conversion circuit 10 can include any voltage conversion circuit for converting AC power to DC power, including but not limited to a three-phase active PFC (Power Factor Correction) circuit, a three-phase neutral-less Vienna circuit, etc.

[0063] The DC / DC circuit 20 is electrically connected to the input filtering and voltage conversion circuit 10, and is used to convert the DC power output from the input filtering and voltage conversion circuit 10 into a voltage waveform that conforms to the battery charging strategy. The DC / DC circuit 20 can be any circuit used to convert the DC power output from the input filtering and voltage conversion circuit 10 into a voltage waveform that conforms to the battery charging strategy, including but not limited to LLC resonant circuits, three-phase interleaved LLC resonant circuits, DAB (dual active bridge converter), bidirectional full-bridge CLLC resonant circuits, three-phase interleaved CLLC resonant circuits, phase-shifted full-bridge circuits, etc.

[0064] The output filter circuit 30 is electrically connected to the DC / DC circuit 20 and the electric vehicle 300 respectively. The output filter circuit 30 is used to filter out the electromagnetic interference generated by the charging pile 100 during operation, to ensure stable communication between the charging pile 100 and the electric vehicle 300, and to avoid charging errors or safety problems caused by interference.

[0065] The auxiliary power supply 40 is electrically connected to the input filtering and voltage conversion circuit 10 and is used to convert the DC power output by the input filtering and voltage conversion circuit 10 into a power supply, which is used to power the charging control module 50.

[0066] The charging control module 50 is electrically connected to the input filtering and voltage conversion circuit 10, the DC / DC circuit 20 and the auxiliary power supply 40, respectively. It is used to operate under the power supply of the auxiliary power supply 40 and control the voltage conversion of the input filtering and voltage conversion circuit 10 and the DC / DC circuit 20.

[0067] The metering module 60 is electrically connected to the charging control module 50. The metering module 60 includes metering, monitoring, and management functions. The metering function is responsible for accurately measuring parameters such as power, voltage, and current during the charging process and feeding the data back to the charging control module 50 to ensure accurate metering of the charging power. The monitoring function is responsible for monitoring the operation of the charging pile 100 in real time, including power, time, and cost, to ensure the normal operation of the charging pile 100. The management function is responsible for managing the charging pile 100, such as setting charging prices, and calculating charging volume and cost, providing data support and business basis for operators.

[0068] The communication module 70 is electrically connected to both the charging control module 50 and the electric vehicle 300, establishing communication between them. Based on this communication, the charging pile 100 can interact with the electric vehicle 300, sending and receiving various charging-related information. The interaction between the electric vehicle 300 and the charging pile 100 during the charging process can be broadly divided into a charging parameter configuration stage and a charging stage. After the charging pile 100 is physically connected to the electric vehicle 300 and powered on, and the voltage is checked to be normal, it enters the charging parameter configuration stage. During the charging stage, the charging pile 100 adjusts the charging voltage and current according to the charging requirements of the electric vehicle 300's battery management system to ensure the charging process proceeds normally.

[0069] In some embodiments, please refer to Figure 3 The input filtering and voltage conversion circuit 10 includes a switching circuit 11, an AC / DC circuit 12, and an EMC filtering circuit 13.

[0070] The switching circuit 11 is configured to be electrically connected to the power grid 200, and is configured to operate in an open state when the charging pile 100 is in standby mode and in an on state when the charging pile 100 is charging. Standby mode refers to the state where the charging pile 100 is ready but not charging the electric vehicle 300, and charging mode refers to the state where the charging pile 100 is charging the electric vehicle 300. In some embodiments, the switching circuit 11 includes any suitable switching device, including but not limited to relays, contactors, etc.

[0071] In some embodiments, the switching circuit 11 is also used to prevent the impact of surge voltage and lightning current from the power grid, thereby avoiding damage to devices such as relays in the switching circuit 11.

[0072] AC / DC circuit 12 is used to convert AC power from the power grid 200 into DC power when the switching circuit 11 is in the ON state. AC / DC circuit 12 can be any voltage conversion circuit used to convert AC power into DC power, including but not limited to three-phase active PFC (Power Factor Correction) circuit, three-phase neutral-less Vienna circuit, etc.

[0073] EMC filter circuit 13 is electrically connected to switch circuit 11 and AC / DC circuit 12 respectively. When switch circuit 11 is in the on state, EMC filter circuit 13 can filter out interference signals from power grid 200 to AC / DC circuit 12. The interference signal can be generated by the power grid or by AC / DC circuit 12. If the interference signal is generated by the power grid, EMC filter circuit 13 can filter out the interference signal transmitted from power grid 200 to AC / DC circuit 12 through AC power, thereby preventing AC / DC circuit 12 from being interfered with. If the interference signal is generated by AC / DC circuit 12, EMC filter circuit 13 can prevent AC / DC circuit 12 from generating interference signals that are transmitted to power grid 200, thereby preventing power grid from being interfered with. When switch circuit 11 is in the on state, EMC filter circuit 13 is disconnected from power grid 200.

[0074] In some embodiments, the EMC filter circuit 13 can be constructed from components such as capacitors or inductors.

[0075] It is understandable that when the charging pile 100 is in standby mode, the switching circuit 11 is in the off state. At this time, the power grid 200 is not electrically connected to the EMC filter circuit 13. Therefore, the capacitors or inductors of the EMC filter circuit 13 will not absorb the energy of the power grid 200. Since there is no capacitive or inductive load, no reactive power is generated when the charging pile 100 is in standby mode.

[0076] Therefore, this embodiment sets up a switching circuit 11 between the power grid 200 and the EMC filter circuit 13. The switching circuit 11 is in the off state when the charging pile 100 is in standby mode. How can the EMC filter circuit 13 avoid absorbing the energy of the power grid 200 and generating reactive power, thereby avoiding impact on the power grid 200?

[0077] In some embodiments, please refer to Figure 4 The switching circuit 11 includes a relay assembly 111 and a relay protection circuit 112.

[0078] The relay assembly 111 is configured to be electrically connected to the power grid 200 and the EMC filter circuit 13 respectively, for making or breaking the electrical connection between the power grid 200 and the EMC filter circuit 13.

[0079] The relay protection circuit 112 is configured to be electrically connected to the power grid 200 and the relay assembly 111 respectively, for protecting the relay assembly 111 from the surge voltage and lightning current of the power grid 200.

[0080] Since the relay assembly 111 is directly electrically connected to the power grid 200, it is easily damaged by the surge voltage and lightning current of the power grid 200 when the relay assembly 111 switches from the off state to the on state. The relay protection circuit 112 can absorb the surge voltage and lightning current of the power grid 200, thereby preventing the relay assembly 111 from being damaged by the surge voltage and lightning current of the power grid 200.

[0081] In some embodiments, please refer to Figure 5 The relay assembly 111 includes a control circuit 1111, a relay module 1112, and a drive module 1113.

[0082] The control circuit 1111 is used to output a control signal. In some embodiments, the control signal is a voltage signal, such as a 12V DC voltage or a 24V DC voltage.

[0083] In some embodiments, the control circuit 1111 may include any general-purpose processor, digital signal processor (DSP), application-specific integrated circuit (ASIC), field-programmable gate array (FPGA), microcontroller, ARM (Acorn RISC Machine) or other programmable logic device, discrete gate or transistor logic, discrete hardware components, or any combination of these components. Additionally, the control circuit 1111 may also include any conventional processor, controller, microcontroller, or state machine. The control circuit 1111 may also be implemented as a combination of computing devices, such as a combination of a DSP and a microprocessor, multiple microprocessors, one or more microprocessors combined with a DSP, and / or any other such configuration.

[0084] The relay module 1112 is configured to be electrically connected to the power grid 200, the relay protection circuit 112, and the EMC filter circuit 13, respectively.

[0085] The drive module 1113 is electrically connected to the control circuit 1111 and the relay module 1112 respectively, and is used to drive the relay module 1112 to work in the on state or the off state in response to the control signal. When the relay module 1112 works in the on state, the power grid 200 and the EMC filter circuit 13 are connected. When the relay module 1112 works in the off state, the power grid 200 and the EMC filter circuit 13 are disconnected.

[0086] In some embodiments, the relay module 1112 includes at least two relays, and the drive module 1113 includes at least two drive units. Each drive unit corresponds to a relay, and each drive unit is electrically connected to the control circuit 1111 and the corresponding relay. It is used to output a drive signal to the corresponding relay in response to the control signal, so that the corresponding relay responds to the drive signal and works in the on state or the off state.

[0087] In some embodiments, please refer to Figure 6 The relay module 1112 includes a first relay K1, a second relay K2, and a third relay K3.

[0088] The first relay K1 is configured to be electrically connected to the first phase line of the power grid 200, the relay protection circuit 112 and the EMC filter circuit 13 respectively; the second relay K2 is configured to be electrically connected to the second phase line of the power grid 200, the relay protection circuit 112 and the EMC filter circuit 13 respectively; and the third relay K3 is configured to be electrically connected to the third phase line of the power grid 200, the relay protection circuit 112 and the EMC filter circuit 13 respectively.

[0089] The first relay K1, the second relay K2, and the third relay K3 can be any type of relay, such as a conventional relay or a magnetic latching relay. The working principle of a conventional relay is as follows: when the relay coil is energized, the coil generates an electromagnetic field, which drives the moving contact of the relay to contact the stationary contact, thus operating in a conducting state. When the relay coil is not energized, the electromagnetic field disappears, and the moving contact separates from the stationary contact, thus operating in an open state. The working principle of a magnetic latching relay is as follows: a permanent magnet is added to the original relay coil design. After the coil is energized, the magnetic field provided by the coil and the permanent magnet triggers the moving contact of the relay to close with the stationary contact. After the current to the coil is disconnected, the magnetic field of the permanent magnet can maintain the relay's closed state. To disconnect the relay, a reverse current needs to be applied to the coil so that the magnetic field generated by the coil cancels out the magnetic field of the permanent magnet.

[0090] It is understandable that the number of relays in relay module 1112 can be determined based on the number of phase lines used. For example, if charging pile 100 only needs to use two phase lines of power grid 200, then relay module 1112 can include only two relays, with one relay corresponding to one phase line.

[0091] In some embodiments, such as Figure 6 As shown, the drive module 1113 includes a first drive unit 11131, a second drive unit 11132 and a third drive unit 11133.

[0092] The first drive unit 11131 is electrically connected to the control circuit 1111 and the first relay K1, the second drive unit 11132 is electrically connected to the control circuit 1111 and the second relay K2, and the third drive unit 11133 is electrically connected to the control circuit 1111 and the third relay K3.

[0093] In some embodiments, please refer to Figure 7 The first driving unit 11131 includes a first capacitor C1, a third common-mode inductor Lc3 and a second capacitor C2.

[0094] The first terminal of the first capacitor C1 is electrically connected to the first input terminal of the control circuit 1111 and the third common-mode inductor Lc3, respectively. The second terminal of the first capacitor C1 is electrically connected to the second input terminal of the control circuit 1111 and the third common-mode inductor Lc3, respectively. The first output terminal of the third common-mode inductor Lc3 is electrically connected to the first terminal of the second capacitor C2 and the first relay K1, respectively. The second output terminal of the third common-mode inductor Lc3 is electrically connected to the second terminal of the second capacitor C2 and the first relay K1, respectively.

[0095] The second drive unit 11132 includes a third capacitor C3, a fourth common-mode inductor Lc4, and a fourth capacitor C4.

[0096] The first terminal of the third capacitor C3 is electrically connected to the first input terminal of the control circuit 1111 and the fourth common-mode inductor Lc4, respectively. The second terminal of the third capacitor C3 is electrically connected to the second input terminal of the control circuit 1111 and the fourth common-mode inductor Lc4, respectively. The first output terminal of the fourth common-mode inductor Lc4 is electrically connected to the first terminal of the fourth capacitor C4 and the second relay K2, respectively. The second output terminal of the fourth common-mode inductor Lc4 is electrically connected to the second terminal of the fourth capacitor C4 and the second relay K2, respectively.

[0097] The third drive unit 11133 includes a fifth capacitor C5, a fifth common-mode inductor Lc5, and a sixth capacitor C6.

[0098] The first terminal of the fifth capacitor C5 is electrically connected to the first input terminal of the control circuit 1111 and the fifth common-mode inductor Lc5, respectively. The second terminal of the fifth capacitor C5 is electrically connected to the second input terminal of the control circuit 1111 and the fifth common-mode inductor Lc5, respectively. The first output terminal of the fifth common-mode inductor Lc5 is electrically connected to the first terminal of the sixth capacitor C6 and the third relay K3, respectively. The second output terminal of the fifth common-mode inductor Lc5 is electrically connected to the second terminal of the sixth capacitor C6 and the third relay K3, respectively.

[0099] Therefore, by introducing a CLC filter circuit into each driving unit, this embodiment can increase the high-frequency impedance of the line, prevent interference signals from being introduced into the input port through the control signal, and prevent EMC from failing to meet the standard requirements, thereby improving the EMC performance of the circuit.

[0100] In some embodiments, such as Figure 7 As shown, the relay protection circuit 112 includes a first resistor R1, a second resistor R2, a third resistor R3, a fourth resistor R4, a fifth resistor R5, a sixth resistor R6, and a switching transistor SQ1.

[0101] The first end of the first resistor R1, the first end of the second resistor R2, and the first end of the third resistor R3 are electrically connected to the first phase line of the power grid 200. The second end of the first resistor R1, the first end of the fourth resistor R4, and the first end of the fifth resistor R5 are electrically connected to the second phase line of the power grid 200. The second end of the second resistor R2, the second end of the fourth resistor R4, and the first end of the sixth resistor R6 are electrically connected. The second end of the third resistor R3, the second end of the fifth resistor R5, and the second end of the sixth resistor R6 are electrically connected to the first end of the switching transistor SQ1. The second end of the switching transistor SQ1 is grounded.

[0102] In some embodiments, the first resistor R1, the second resistor R2, the third resistor R3, the fourth resistor R4, the fifth resistor R5, and the sixth resistor R6 are varistors. Varistors are mainly used for overvoltage protection in electronic circuits, limiting atmospheric overvoltages and operational overvoltages. When the voltage is below the rated value, the resistance of the varistor is almost infinite, while when the voltage slightly exceeds the rated value, the resistance drops sharply, with a response time on the order of nanoseconds. This nonlinear characteristic allows the varistor to quickly conduct under overvoltage conditions, thereby protecting downstream circuits.

[0103] The switching transistor SQ1 can be any suitable type of electronic switching transistor. In some embodiments, the switching transistor is a gas switching transistor. The gas discharge tube is filled with inert gas. When the voltage between the two electrodes is large enough, the inert gas will be ionized and discharged, causing the discharge tube to change from an insulating state to a conductive state, similar to a short circuit. In the conductive state, the voltage maintained between the two electrodes is very low, generally between 20 and 50V, thereby protecting the downstream circuitry.

[0104] Understandably, when a surge voltage or lightning current occurs in the power grid 200, the switching transistor SQ1 operates in the on state, discharging high voltage and large current, thus absorbing the surge voltage or lightning current, reducing the impact of the surge voltage or lightning current on the relay module 1112, and preventing damage to the relay module 1112.

[0105] In some embodiments, such as Figure 7 As shown, the EMC filter circuit 13 includes a first capacitor bank 131, a first common-mode inductor Lc1, and a second capacitor bank 132.

[0106] The first capacitor bank 131 is configured to be electrically connected to the power grid 200.

[0107] In some embodiments, the first capacitor group 131 includes a seventh capacitor C7, an eighth capacitor C8, and a ninth capacitor C9.

[0108] The first terminal of the seventh capacitor C7 is electrically connected to the first terminal of the eighth capacitor C8, the first relay K1, and the first common-mode inductor Lc1, respectively. The second terminal of the seventh capacitor C7 is electrically connected to the first terminal of the ninth capacitor C9 and the second relay K2, respectively. The second terminal of the eighth capacitor C8 is electrically connected to the second terminal of the ninth capacitor C9, the third relay K3, and the first common-mode inductor Lc1, respectively.

[0109] The first common-mode inductor Lc1 is configured to be electrically connected to the first capacitor bank 131 and the power grid 200, respectively.

[0110] In some embodiments, the first input terminal of the first common-mode inductor Lc1 is electrically connected to the first terminal of the seventh capacitor C7, the first terminal of the eighth capacitor C8, and the first relay K1, respectively. The second input terminal of the first common-mode inductor Lc1 is electrically connected to the second terminal of the seventh capacitor C7, the first terminal of the ninth capacitor C9, and the second relay K2, respectively. The third input terminal of the first common-mode inductor Lc1 is electrically connected to the second terminal of the eighth capacitor C8, the second terminal of the ninth capacitor C9, and the third relay K3, respectively. The first, second, and third output terminals of the first common-mode inductor Lc1 are electrically connected to the second capacitor bank 132 and the AC / DC circuit 12.

[0111] The second capacitor bank 132 is configured to be electrically connected to the first common-mode inductor Lc1 and the AC / DC circuit 12, respectively.

[0112] In some embodiments, the second capacitor group 132 includes a tenth capacitor C10, an eleventh capacitor C11, and a twelfth capacitor C12.

[0113] The first terminal of the tenth capacitor C10 is electrically connected to the first output terminal of the first common-mode inductor Lc1, the first terminal of the eleventh capacitor C11, and the AC / DC circuit 12. The second terminal of the tenth capacitor C10 is electrically connected to the first terminal of the twelfth capacitor C12, the second output terminal of the first common-mode inductor Lc1, and the AC / DC circuit 12. The second terminal of the eleventh capacitor C11 is electrically connected to the second terminal of the twelfth capacitor C12, the third output terminal of the first common-mode inductor Lc1, and the AC / DC circuit 12.

[0114] Therefore, this embodiment uses the first capacitor group 131, the first common-mode inductor Lc1 and the second capacitor group 132 to form a CLC filter circuit, which can provide a more stable and efficient filtering effect and improve the filtering performance.

[0115] In some embodiments, please refer to Figure 8 The EMC filter circuit 13 includes a second common-mode inductor Lc2 and a third capacitor bank 133.

[0116] The second common-mode inductor Lc2 is configured to be electrically connected to the first common-mode inductor Lc1 and the second capacitor bank 132, respectively.

[0117] In some embodiments, the first input terminal of the second common-mode inductor Lc2 is electrically connected to the first output terminal of the first common-mode inductor Lc1, the first terminal of the tenth capacitor C10, and the first terminal of the eleventh capacitor C11, respectively. The second input terminal of the second common-mode inductor Lc2 is electrically connected to the second terminal of the tenth capacitor C10, the first terminal of the twelfth capacitor C12, and the second output terminal of the first common-mode inductor Lc1, respectively. The third input terminal of the second common-mode inductor Lc2 is electrically connected to the second terminal of the eleventh capacitor C11, the second terminal of the twelfth capacitor C12, and the third output terminal of the first common-mode inductor Lc1, respectively. The first, second, and third output terminals of the second common-mode inductor Lc2 are electrically connected to the third capacitor group 133 and the AC / DC circuit 12, respectively.

[0118] The third capacitor bank 133 is configured to be electrically connected to the second common-mode inductor Lc2 and the AC / DC circuit 12, respectively.

[0119] In some embodiments, the third capacitor group 133 includes a thirteenth capacitor C13, a fourteenth capacitor C14, and a fifteenth capacitor C15.

[0120] The first terminal of the thirteenth capacitor C13 is electrically connected to the first terminal of the fourteenth capacitor C14, the first output terminal of the second common-mode inductor Lc2, and the AC / DC circuit 12, respectively. The second terminal of the thirteenth capacitor C13 is electrically connected to the first terminal of the fifteenth capacitor C15, the second output terminal of the second common-mode inductor Lc2, and the AC / DC circuit 12, respectively. The second terminal of the fourteenth capacitor C14 is electrically connected to the second terminal of the fifteenth capacitor C15, the third output terminal of the second common-mode inductor Lc2, and the AC / DC circuit 12, respectively.

[0121] Therefore, in this embodiment, a first-stage CLC filter circuit is formed by the first capacitor group 131, the first common-mode inductor Lc1, and the third capacitor group 133, and another-stage CLC filter circuit is formed by the second capacitor group 132, the second common-mode inductor Lc2, and the third capacitor group 133, thus realizing two-stage filtering and further improving the filtering performance.

[0122] In some embodiments, please refer to Figure 9 The input filtering and voltage conversion circuit 10 also includes a fuse circuit 14.

[0123] Fuse circuit 14 is configured to be electrically connected to both the mains power 200 and the switching circuit 11. Fuse circuit 14 serves as short-circuit or overcurrent protection in the circuit, preventing fires caused by short circuits or overcurrents.

[0124] In some embodiments, please continue reading Figure 7 The fuse circuit 14 includes a first fuse F1, a second fuse F2 and a third fuse F3.

[0125] The first end of the first fuse F1 is configured to be electrically connected to the first phase line L1 of the power grid 200, and the second end of the first fuse F1 is electrically connected to the switching circuit 11.

[0126] The first end of the second fuse F2 is configured to be electrically connected to the second phase line L2 of the power grid 200, and the second end of the second fuse F2 is electrically connected to the switching circuit 11.

[0127] The first end of the third fuse F3 is configured to be electrically connected to the third phase line L3 of the power grid 200, and the second end of the third fuse F3 is electrically connected to the switching circuit 11.

[0128] The working principle of a fuse is as follows: when the current in the circuit exceeds the rated current of the fuse, the fuse will melt quickly, cutting off the circuit and thus protecting other components and equipment in the circuit from damage caused by overcurrent.

[0129] Finally, it should be noted that this utility model can be implemented in many different forms and is not limited to the embodiments described in this specification. These embodiments are not intended to impose additional limitations on the content of this utility model. The purpose of providing these embodiments is to make the disclosure of this utility model more thorough and comprehensive. Furthermore, within the framework of this utility model, the above-mentioned technical features can be combined with each other, and there are many other variations of different aspects of this utility model as described above, all of which are considered to be within the scope of this utility model specification. Moreover, those skilled in the art can make improvements or modifications based on the above description, and all such improvements and modifications should fall within the protection scope of the appended claims.

Claims

1. A charging pile, characterized in that, include: The switching circuit is configured to be electrically connected to the power grid, and operates in an open state when the charging pile is in standby mode and in an on state when the charging pile is in charging mode. An AC / DC circuit is used to convert the alternating current (AC) of the power grid into direct current (DC) when the switching circuit is in the on state. The EMC filter circuit is electrically connected to both the switching circuit and the AC / DC circuit, and is used to filter out interference signals from the power grid to the AC / DC circuit.

2. The charging pile according to claim 1, characterized in that, The switching circuit includes: A relay assembly is configured to be electrically connected to the power grid and the EMC filter circuit respectively, for making or breaking the electrical connection between the power grid and the EMC filter circuit; A relay protection circuit is configured to be electrically connected to the power grid and the relay assembly respectively, for protecting the relay assembly from the surge voltage and lightning current of the power grid.

3. The charging pile according to claim 2, characterized in that, The relay assembly includes: Control circuit, used to output control signals; The relay module is configured to be electrically connected to the power grid, the relay protection circuit, and the EMC filter circuit, respectively. The drive module is electrically connected to the control circuit and the relay module respectively, and is used to drive the relay module to work in the on state or the off state in response to the control signal. When the relay module works in the on state, the power grid is connected to the EMC filter circuit. When the relay module works in the off state, the power grid is disconnected from the EMC filter circuit.

4. The charging pile according to claim 3, characterized in that, The relay module includes: The first relay is configured to be electrically connected to the first phase line of the power grid, the relay protection circuit and the EMC filter circuit respectively. The second relay is configured to be electrically connected to the second phase line of the power grid, the relay protection circuit, and the EMC filter circuit, respectively. The third relay is configured to be electrically connected to the third phase line of the power grid, the relay protection circuit, and the EMC filter circuit, respectively.

5. The charging pile according to claim 4, characterized in that, The drive module includes: The first drive unit is electrically connected to the control circuit and the first relay, respectively; The second drive unit is electrically connected to the control circuit and the second relay, respectively; The third drive unit is electrically connected to both the control circuit and the third relay.

6. The charging pile according to claim 2, characterized in that, The relay protection circuit includes a first resistor, a second resistor, a third resistor, a fourth resistor, a fifth resistor, a sixth resistor, and a switching transistor; The first end of the first resistor, the first end of the second resistor, and the first end of the third resistor are electrically connected to the first phase line of the power grid. The second end of the first resistor, the first end of the fourth resistor, and the first end of the fifth resistor are electrically connected to the second phase line of the power grid. The second end of the second resistor, the second end of the fourth resistor, and the first end of the sixth resistor are electrically connected. The second end of the third resistor, the second end of the fifth resistor, and the second end of the sixth resistor are electrically connected to the first end of the switching transistor. The second end of the switching transistor is grounded.

7. The charging pile according to claim 1, characterized in that, The EMC filtering circuit includes: The first capacitor bank is configured to be electrically connected to the power grid; The first common-mode inductor is configured to be electrically connected to the first capacitor bank and the power grid, respectively. The second capacitor bank is configured to be electrically connected to the first common-mode inductor and the AC / DC circuit, respectively.

8. The charging pile according to claim 7, characterized in that, The EMC filtering circuit also includes: The second common-mode inductor is configured to be electrically connected to the first common-mode inductor and the second capacitor bank, respectively. The third capacitor bank is configured to be electrically connected to the second common-mode inductor and the AC / DC circuit, respectively.

9. The charging pile according to any one of claims 1 to 8, characterized in that, It also includes fuse circuits; The fuse circuit is configured to be electrically connected to both the power grid and the switching circuit.

10. The charging pile according to claim 9, characterized in that, The fuse circuit includes: A first fuse, wherein a first end of the first fuse is configured to be electrically connected to a first phase line of the power grid, and a second end of the first fuse is electrically connected to the switching circuit; A second fuse, the first end of which is configured to be electrically connected to the second phase line of the power grid, and the second end of which is electrically connected to the switching circuit; A third fuse, the first end of which is configured to be electrically connected to the third phase line of the power grid, and the second end of which is electrically connected to the switching circuit.

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