Vehicle charging station

Abstract

The invention relates to a vehicle charging station (500) comprising a holder configured to hold a battery charging connector (100) and a cooling device configured to remove heat from a heat source of the battery charging connector (100) when the battery charging connector is located on the holder and to dissipate the heat into ambient air.

Description

Technical Field

[0001] This invention relates to a vehicle charging station for electric vehicles, and the use of heat pipes in the vehicle charging station. Background Technology

[0002] One limiting factor in charging cables for electric vehicles is the heat generated as high current flows from the charging station through the cable and connectors to the vehicle's battery. Heat can be actively conducted away from the heat source using liquids. This allows for rated currents exceeding 500A. For this type of cooling, battery charging connectors are designed to actively or passively remove heat from the heat source, such as using liquid-cooled cables, openings or cavities in the housing, or housing materials that do not insulate against heat. This design can be ineffective or result in a heavier charging cable. One reason for high temperatures after short charging cycles is that, in some cases, the initial temperature is already high. This occurs when there is insufficient time for the charging connectors to cool between two charging cycles. Summary of the Invention

[0003] The purpose of this invention is to provide a battery charging connector with improved thermal performance.

[0004] The aforementioned problems are addressed by the subject matter of the independent claims. Examples are provided by the dependent claims, the following description, and the accompanying drawings.

[0005] The described embodiments similarly relate to charging stations and the use of heat pipes in vehicle charging stations. Synergistic effects can arise from different combinations of embodiments, although they may not be described in detail.

[0006] Technical terms are used as they usually mean. If a specific meaning is to be conveyed to certain terms, the definition of the term will be given below in the context in which it is used.

[0007] According to a first aspect, a vehicle charging station is provided, comprising: a retainer configured to hold a battery charging connector; and a cooling device configured to remove heat from a heat source of the battery charging connector when the battery charging connector is in the retainer, and to dissipate the heat into ambient air. In other words, as an alternative or additional measure to cooling arrangements located in or attached to the charging connector, the vehicle charging station includes arrangements for cooling the charging connector, or more precisely, cooling the heat source of the charging connector. The heat source in the connector is primarily the electrical contacts, which contact the electrical contacts of a socket on the vehicle side during battery charging of the vehicle. The transfer of load current from the charging connector to the socket on the vehicle side generates heat on both sides, preventing heat dissipation to the vehicle side. Therefore, heat remains in the electrical contacts of the charging connector and is also conducted to the cable attached to the electrical contacts, which can therefore also be considered a heat source. Due to the limited possibility of heat dissipation in the charging connector, heat is also retained in the connector after the charging process is complete and decreases slowly over time. This means that if another charging session begins immediately after the previous one, the power contacts are still hot, meaning the starting point for temperature rise is already high. Therefore, the first aspect presented provides an arrangement that reduces the heat of the power contacts of the charging connector once the charging connector is placed on the holder of the charging station. For this purpose, the station includes at least one cooling device or arrangement, which will be described in the embodiments below.

[0008] In this disclosure, the term "battery charging connector" refers to a charging connector used in electric vehicles. The battery charging connector is connected to a vehicle charging station via a cable.

[0009] According to one embodiment, the cooling device is a passive cooling device configured to be inserted into a socket of the battery charging connector, thereby providing a thermal connection to a heat source of the battery charging connector. That is, the charging station, or more precisely, the retainer, receives the battery charging connector, or from the user's perspective, the user inserts the charging connector into the passive cooling device. Therefore, the passive cooling device has a shape suitable for direct connection to a heat source. Thus, at least with respect to the connector reception and the contact between the power connector of the charging connector and the cooling device, the arrangement of the passive cooling device and / or the design of the retainer can be similar to the design of the corresponding portion of the charging connector, which is the socket on the vehicle side. The cooling device can therefore have contacts corresponding to the power contacts on the vehicle side, however, having a cooling function rather than a power conduction function. It should be noted that more than one contact may exist, which can be cooled in the same manner.

[0010] According to one embodiment, the passive cooling device includes cooling fins. That is, the cooling device has a portion that contacts the power contacts of the charging connector inside the charging connector upon insertion and a portion outside the charging connector, said portion being designed to provide an extended surface suitable for heat dissipation. The extended surface is the surface of the cooling fins.

[0011] According to one embodiment, a passive cooling device is a heat pipe comprising condenser fins. The heat pipe includes an evaporator and a condenser, the condenser typically being finned, where steam is generated due to heat from a connected heat source. The steam flows from the evaporator through a pipe or conduit to the condenser, where it condenses back into water. This passive, liquid-based cooling device provides efficient cooling for electrical contacts.

[0012] According to one embodiment, the vehicle charging station also includes an active cooling device. "Active" means that the cooling device is electrically driven. Although the arrangement including the active cooling device may be integrated with the thermally receiving portion of the electrical contacts of the charging connector, the thermally receiving portion is defined herein as a "passive cooling device" or apparatus, such that the active cooling device can be considered in combination with a passive cooling device in this context.

[0013] According to one embodiment, the active cooling device is a fan. The fan circulates ambient air around the retainer and connector, allowing heat to be largely removed.

[0014] According to one embodiment, the active cooling device is configured to direct airflow to at least one passive cooling device in the charging station or at least one passive device of the charging connector. For example, a fan is directed such that the airflow impacts the cooling fins or condenser fins of a passive cooling device in the charging station. In another example, the connector includes one or more heat pipes having condenser fins outside its outer housing. When the passive cooling device is a fan, the fan may be configured such that air from the fan is directed to these condenser fins.

[0015] According to one embodiment, the vehicle charging station further includes a temperature sensor and control circuitry, wherein the control circuitry is configured to control the active cooling device based on the temperature. That is, for example, the active cooling device is activated only when cooling of the charging connector is required. Several possible locations can be provided for the temperature sensor. For example, the sensor could be located somewhere on the passive cooling device or attached to a retainer to measure the temperature of the airflow received from the fan. As an example, the control circuitry could be configured to always activate the active cooling device when it detects that the charging connector is placed on the retainer, and deactivate the active cooling device when it detects that the charging connector is removed from the retainer. It can also be configured to control the intensity of the airflow based on the temperature.

[0016] According to one embodiment, the vehicle charging station further includes a clock and control circuitry, wherein the control circuitry is configured to activate and / or deactivate the active cooling device according to a predefined time using the clock. The activation time period can be defined based on a known temperature profile indicating the time required to cool the heat source. It can also depend on the battery charging process, such as time and electrical power output.

[0017] According to one embodiment, the active cooling device is a pump configured to provide liquid cooling to the passive cooling device. The liquid may be in direct contact with the passive cooling device, for example, flowing around the fins, or it may be separated, thereby allowing the liquid to absorb and dissipate heat.

[0018] According to one embodiment, the vehicle charging station also includes a mechanical temperature switch to activate and / or deactivate the active cooling device. That is, for example, the active cooling device can be switched on and off by a passive temperature-sensitive switch (replacing a temperature sensor) such as a bimetallic strip. The bimetallic strip can be disposed on, for example, a passive cooling device.

[0019] According to one embodiment, a vehicle charging station includes a liquid-cooled rod configured to insert into electrical contacts, wherein the active cooling device is a pump connected to the liquid-cooled rod and configured to provide a liquid flow to and from the rod. For example, the liquid can flow inside or outside the rod. The diameter of the rod portion configured to contact the electrical contacts (i.e., the inner portion) of the charging connector can differ from the outer portion of the charging connector, allowing the liquid to be effectively applied to the outer portion. The rod may also include a U-shaped tube for circulating the liquid, the U-shaped tube being connected to the inner portion of the charging station to be inserted.

[0020] According to one aspect, an active cooling device (e.g., a fan) is provided for use in a charging station according to any one of the preceding claims. Specifically, when the vehicle charging connector is not in operation, the active cooling device is used to cool the heat source of the vehicle charging connector.

[0021] According to one aspect, there is provided the use of a heat pipe in a vehicle charging station according to any one of the preceding claims.

[0022] These and other features, aspects, and advantages of the invention will be better understood with reference to the accompanying drawings and the following description. Identical or equivalent elements generally have the same reference numerals. Attached Figure Description

[0023] Figure 1 A diagram of a battery charging connector with a heat pipe is shown.

[0024] Figure 2aA diagram of a dual heat pipe system with two heat pipes arranged alongside the condenser fins is shown.

[0025] Figure 2b A diagram shows a grid that can be used to protect the heat pipe condenser on the battery charging connector.

[0026] Figure 3 The temperature profile of the charging cycle is shown.

[0027] Figure 4 A thermal network diagram of the battery charging connector is shown.

[0028] Figure 5 The diagram shows a battery charging connector and a fan inside the charging station. When the battery charging connector is placed on the retainer, the components of the battery charging connector can be located outside or inside the charging station.

[0029] Figure 6a The arrangement of a fan in a charging station is shown.

[0030] Figure 6b The diagram shows an arrangement with two fans in a charging station.

[0031] Figure 7 Passive and active cooling devices in a charging station are shown. Detailed Implementation

[0032] Figure 1A charging connector 100 including an outer housing 104 is shown. The charging connector 100 is configured to receive a cable 101 and guide the cable 101 from a rear end 111 to a front end 113, and encapsulates a compartment 102 or contact holder 102 within the front end 113, which houses electrical contacts. The cable 101 is connected to the compartment or contact holder 102 within the front end 113 inside an inner housing 103. The inner housing 103 functions to ensure electrical insulation, mechanical strength, and protection against water and dust contamination. For this purpose, the housing 103 is largely sealed and, in some designs, may have a nearly completely enclosed structure. The contact holder 102 can also be treated in this manner. The combination of components 102 and 103 is further enclosed by the outer housing 104. A heat pipe 106, acting as a heat conductor, is arranged within the housings 103 and 104. The heat pipe 106 is attached to the connector 102, where heat is absorbed by an evaporator 107. Heat is then transferred from evaporator 107 via seal 110 to condenser 109 having condenser fins 108. The evaporator of heat pipe 106 is attached to connector 102 at one or more locations. Heat pipe 106 is integral with inner housing 102 and is sealed at location 110 to allow access to the outside of 102. Heat pipe 106 may also be connected to any critical portion of inner housing 103. Heat pipe 106 is attached to a heat source to ensure good thermal contact. Heat pipe 106 may be electrically insulated, for example, by solid insulation between heat pipe evaporator section 107 and live parts. Alternatively, heat pipe 106 may be grounded. Condenser 108 may be located outside outer housing 104 and protected, for example, by a grille, or inside outer housing, wherein outer housing may include air passages or openings 132 exposing heat pipe condenser end 109 to ambient air. These channels can, for example, be formed by open hollow sections, which may have covers on the sides of the outer housing 104 to prevent users from contacting the heat pipe 106. Figure 2b The figure shows a cover with a grille 134, in which the heat pipe condenser 108 is exposed to the environment, and the appropriate surface of the finned external connector is exposed, if possible, covered only by the protective grille 134.

[0033] Figure 2b A dual heat pipe 136 is shown, having two heat pipes arranged side-by-side, with a set of condenser fins 108 attached to the pipes. The condenser fins 108 improve heat emission due to the reinforced surface at the condenser end 109 of the heat pipes. The fins 108 shown can be adapted to available space within the outer housing 104.

[0034] In some situations, it is desirable to cool connector 100 as quickly as possible to restore it to its initial state, so that connector 100 is ready for the next charge, etc. Figure 3In this process, charging occurs from time 0 to time "te", at which point the current is disconnected, as shown by curve 302. Without additional measures, connector 100 begins to cool along curve 304 at a rate highly dependent on design, environmental conditioning, etc. If connector 100 is placed at a charging station (also referred to as a charging pile in this disclosure) at time "te" and forced cooling is initiated, the cooling time will be significantly shortened, following curve 306. In this case, the charger is ready for the next charge at time t1, which is much earlier than t2.

[0035] Therefore, as described below, forced cooling (i.e., forced convection) is added to the system to remove heat more quickly. In principle, forced cooling can be applied to any area of ​​connector 100. Heat dissipation in area 108 is considered passive and can be addressed through appropriate design (e.g., by the appropriate size and shape of the air passages) to maximize thermal performance. Airflow is further improved by using thermal expansion to drive flow more effectively.

[0036] This modification significantly reduces the thermal resistance of the connector system and extends the system's ratings in both transient and steady-state conditions. In this improved arrangement, a significant amount of heat loss is removed from the system solely through the heat pipes and condenser fins. Therefore, by adding a cooling fan to enhance convection, a means is provided to significantly reduce the connector's cooling time when it is not in operation. The primary target of this measure is the area around the cooler on the condenser side of the heat pipe 106, which exhibits high thermal resistance unless a very large and complex fin structure is used. Forced cooling is particularly beneficial in designs with heat pipes. In this case, heat is primarily removed at a well-defined location, namely the condenser / fin region 108. The concentrated airflow in this region can be more helpful compared to the case without heat pipe 106 and air blowing across the entire connector 100. In the former case, convection is significantly enhanced in the region having a rapid thermal link with the hottest area of ​​the connector (i.e., the area 102 where the contacts are located). In the latter case, the internal structure remains fairly insulated, and the effect of forced convection around the connector is limited. Figure 3 The expected results are shown. Under fast charging / high-current charging conditions, the temperature increases as shown in curve 302 after charging begins, until charging is complete or the thermal limit is reached. At this point, charging stops, is interrupted, or the charging current decreases. In principle, a steady state can also be reached, in which case the charging time can be extended to a very long period.

[0037] Figure 4A thermal network diagram of the battery charging connector is shown. Heat pipe 106 in the inner housing 103 is considered by resistor R9, while heat pipe 106 in the outer housing is considered by resistor R10 corresponding to the pipe in the outer housing 104 and resistor R11 corresponding to fin 108. Heat absorbed by the evaporator section 107 of heat pipe 106, R9, is directed by heat pipe 106 to condenser regions 106, R10, R11. The thermal path is enhanced by adding a fan 152 or other forced convection device to reduce the thermal resistance R11 between the condenser 109 and the surrounding environment. In practice, the enhancement can be quite fundamental. For a passive cooler, the heat transfer coefficient can be on the order of W / m²K, while with fan 152 assistance, tens or hundreds of W / m²K can be achieved. The cooling fan 152 can operate continuously or at given intervals. Therefore, the charging station 500 may include a clock and control unit. The fan 152 may be mounted on connector 100 or elsewhere. In one embodiment, at least one cooling fan 152 is installed at the charging station 500, near the area where the connector 100 is placed between charging uses, such as Figure 5 As shown. Cooling may only begin temporarily.

[0038] Figure 5 A charging station 500 including a fan 152 or a holder having a fan 152 is schematically shown, which increases convection around region 109 of the cooler (e.g., fins 108) of the heat pipe 106 in the passively cooled connector 100.

[0039] Figure 6a and 6b The rear view shows a possible arrangement. Heat pipe condenser fins 108 are disposed in a channel, through which a fan 152 forces air. Various arrangements are possible depending on the condenser's location, fin design, and the number of heat pipes. For example, in... Figure 6a The image shows a fan with an air passage 602 leading to two finned devices 108. Figure 6b The image shows two fans 152 and 162, each fan for each fin assembly 108, wherein individual air channels 604 are combined together such that air is guided away from the fin assembly 108 in an orthogonal direction.

[0040] Figure 7An example of a charging station 500 is shown, which includes a retainer with a heat pipe 154 connected to cooling fins 155 cooled by a fan 152. The heat pipes 154, 106 connect to an area surrounding the contact element 102 of a passively cooled connector 100. The retainer in the charging station may be equipped with an equivalent automotive socket that provides good thermal contact with the area of ​​the contact element 102 of the connector 100. This "automotive socket," replicated in this manner, includes the heat pipe 154 (replacing the contact element), and the heat pipe 154 connects to condenser fins 155 within the charging station 500. The fan 152 can be used to enhance convection around the condenser fins 155 within the charging station 500.

[0041] However, the present invention is not limited to the arrangement of condenser fins 155 and a fan 152 for cooling the fins. Typically, the retainer of the replicated automotive socket can be cooled in any manner. For example, liquid cooling can also be applied. In this case, a cooling circuit can be used, for example, which also cools the power electronic components inside the charging station 500.

[0042] Therefore, expensive active cooling cable structures are not required. The presented embodiments and arrangements are independent of the design of the battery charging connector. In particular, they are independent of, for example, the design of openings and slots in the outer housing of connector 100. Furthermore, the presented embodiments are applicable to dual-housing designs with an outer housing 104 and an inner housing 102.

[0043] By studying the accompanying drawings, the disclosure, and the appended claims, those skilled in the art can understand and implement other variations of the disclosed embodiments in practicing the claimed invention. In the claims, the word "comprising" does not exclude other elements or steps, and the indefinite articles "a" or "an" do not exclude a plurality. The fact that certain measures are recited in mutually different dependent claims does not imply that combinations of these measures cannot be advantageously used. Any reference numerals in the claims should not be construed as limiting the scope of the claims.

Claims

1. A vehicle charging station (500), comprising: A retainer is configured to retain the battery charging connector (100). as well as An active cooling device is configured to remove heat from a heat source of the battery charging connector (100) when the battery charging connector (100) is on the retainer, and to dissipate the heat into the ambient air. The heat source is the power contact of the battery charging connector, which contacts the power contact of the socket on the vehicle side during battery charging. The vehicle charging station includes a liquid-cooled rod configured to be inserted into the electrical contacts. The active cooling device is a pump connected to the liquid-cooled rod and configured to provide a liquid flow to and from the rod.

2. The vehicle charging station (500) according to claim 1, wherein the vehicle charging station (500) further includes a temperature sensor and a control circuit, wherein the control circuit is configured to control the active cooling device based on the temperature measured by the temperature sensor.

3. The vehicle charging station according to claim 1 or 2, wherein the vehicle charging station (500) further includes a clock and control circuitry, wherein the control circuitry is configured to activate and / or deactivate the active cooling device according to a predetermined time using the clock.

4. The vehicle charging station (500) according to claim 1 or 2, wherein the vehicle charging station (500) further comprises a mechanical temperature switch to activate and / or deactivate the active cooling device.

5. Use of an active cooling device (130) in a vehicle charging station (500) according to any one of the preceding claims.

6. Use of a heat pipe (130) in a vehicle charging station (500) according to any one of claims 1 to 4.

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