SE534524C2 - Battery charging system - Google Patents

Abstract

SUMMARY A system for distributing electricity to a plurality of temporarily parked electric cars comprising a parking surface (13), a plurality of electrical outlets (12) and an input transformer station comprising a transformer (7), a low voltage switchgear (8) and a high voltage switchgear (1). 2). The transformer (7) is located adjacent to the parking surface. (Fig. 1)

Description

534 524 2 The crucial thing for the application of this invention is that electrical energy can be charged and stored in the vehicle.

By US 2007/0126395 (Suchar) an automatic charging and docking station for electric cars is previously known. The known station is intended to be located in public or private places and comprises a probe carried by the vehicle which is brought into contact with the station during charging. The probe contains an identity carrier that allows the owner to be invoiced afterwards.

US 5,548,200 (Nor et al) discloses a universal charging station for charging batteries for electric cars. The task of the charging station is to allow the transfer of electrical energy to a battery as quickly as possible. The problem that the charging station seeks to overcome is that drivers do not have to wait several hours or overnight to get their car charged. The known station comprises a rectifier which supplies a plurality of charging sockets with direct current. In this case, vehicles and stations are arranged to communicate with each other to control the charging phase.

The electric cars that are developed today will usually include a connection section where a standard low-current plug is connected to an electrical outlet.

Usually this includes a household current of about 230 V AC.

This can vary with respect to different countries but stays within the range of 100 to 500 volts. The electric cars thus carry their own rectifier for converting alternating current into a direct current suitable for charging the battery. However, the energy supply in the connection section is critical as several connected electric cars charge their batteries at the same time. DISCLOSURE OF THE INVENTION The object of the invention is to provide ways of producing a plant for providing a strong charging current to a plurality of temporarily connected electric cars.

These objects are achieved according to the invention by a plant according to the features specified in the characterizing part of independent claim 1 and by a method according to the features specified in the characterizing part of independent claim 9. Advantageous embodiments are set out in the characterizing parts of the dependent claims.

According to the invention, the plant comprises a parking area with an energy supply system containing a plurality of connection points for electric cars and a transformer station for direct connection to a distribution network. By distribution network is meant a power network between 10 to 36 kv but also up to 54 kV. In addition to a transformer, the transformer station includes a low-voltage switchgear and a high-voltage switchgear. The transformer is the system's pressure point and is placed close to the parking surface. The high-voltage switchgear is placed near the connection to the power grid and is connected to the transformer with a high-voltage cable. By separating the transformer and the high-voltage switchgear in this way, losses that usually occur during long-distance transport of low-voltage are avoided. The high voltage switchgear is thus located at a distance from the transformer. Rated data for the transformer can be 10-24 / 0.4 kV.

In one embodiment, the plant contains a transformer that is submerged underground. The transformer is then placed in a box made of, for example, concrete that can be prefabricated or site-built. A cover is placed over the transformer, the cover containing passageways for connection of switchgear and ventilation. The lid may also contain an inspection hatch. In one embodiment, the low voltage switchgear is located on the lid of the box. In this embodiment, the low voltage 534,524 contains. 4 switchgear enclosure also fans for ventilation of the box. In another embodiment, the ventilation is arranged separately.

The high-voltage switchgear includes a T-branch and a switch arranged on the branch. The connection of the high-voltage switchgear thus takes place in a way that does not interfere with the distribution in the power grid.

Regardless of whether the connected switch is switched off or on, the distribution is not affected. In addition to normal switches on and off, the switch is arranged to break in the event of a short circuit and earth fault. Triggering takes place within a time delay that is shorter than the reaction time of switches in the distribution network.

In this way, faults located downstream of the T-branch do not affect the power grid. In one embodiment, the switch measuring device and tripping device are operated with current from the low voltage side of the transformer.

In the event of a power failure, the secondary side of the transformer contains enough energy to detect the fault and trip the switch.

The parking area contains a power supply system with several electrical outlets for connection of a temporarily parked electric vehicle. In one embodiment, the system contains a network of cables that connect a number of electrical outlets to the low-voltage switchgear. In a further embodiment, an electrical socket comprises a post with a connection module containing one or more sockets. In one embodiment, the parking surface comprises a branch system of cable protection. The cable guards are attached to the parking surface and surround the cables. In one embodiment, the cable guards also form the frame of the posts. Because the cables are routed in the cable guards, the cables do not have to be buried, which offers great flexibility and low construction costs.

According to a first aspect of the invention, the object is achieved by a plant for distributing electricity to a plurality of temporarily parked electric cars comprising a parking surface, a plurality of electrical outlets and a transformer for connection to a power grid, the transformer being located adjacent to the parking surface. The transformer system comprises 534 524 in addition to the transformer a low-voltage switchgear and a high-voltage switchgear, the high-voltage switchgear being located at the high-voltage connection. In one embodiment, the high-voltage connection comprises a T-branch with a switch that is tripped in a shorter time than other switches in the power grid.

According to a second aspect of the invention, the object is achieved with a method in a plant for distributing electricity to a plurality of temporarily parked electric cars comprising a parking surface, a plurality of electrical outlets and a transformer for connection to a power network, where the transformer converts high voltage alternating current to low voltage alternating current. to the electric car, whereby the transformer is arranged in connection with the parking surface and is supplied with high voltage from a power grid located at a distance.

DESCRIPTION OF THE DRAWINGS The invention will be explained in more detail by describing exemplary embodiments with reference to the accompanying drawings, in which Fig. 1 is a diagrammatically shown plant for supplying a plurality of electric vehicles according to the invention, Fig. 2 is a high voltage switchgear for such a plant connected to a distribution network. Fig. 3 is a transformer plant according to the invention with the transformer placed underground and connected to a low voltage switchgear located above ground, and Fig. 4 is an embodiment of a power supply system with a cable protection with poles containing electrical outlets for connection of an electric car. 534 524 6 DESCRIPTION OF EXEMPLARY EMBODIMENT The plant according to Figure 1 is arranged for an infrastructure such as electricity supply, metering, control and payment systems for charging electric and electric hybrid cars in connection with them being parked.

Since the power output is quite large from each car and it takes less than 5 - 6 hours to charge a battery, there is usually no possibility to draw power supply from the nearest power station. On the one hand, there is usually no capacity and on the other hand, the low-voltage cables become long and thus both expensive and encumbered with large losses. According to the invention, the system is designed so that the electrical pressure point, the transformer, comes in direct connection with the parking space.

Power supply is obtained by connecting a high-voltage switchgear 1 with a T-branch in a suitable place in an existing cable-fed mains station loop 2. Usually such a connection is 10 or 24 kV. The connection point is chosen so that a minimum distance is obtained but also so that a suitable room is obtained where the switchgear can be installed in collaboration with nature. The switchgear contains a switch 3 for switching on and off and a ballast 4 for tripping the switch in the event of a power failure. The special design of the T-branch means that its outer dimensions are limited and that it can thus be set up without a building permit.

From a high-voltage switchgear 1, a radially output cable 5, which is intended for 10-36 kV, goes to a transformer system 6 which is advantageously placed underground as it does not steal existing ground surface nor does it change or disturb the environment aesthetically. A distribution transformer 7 is normally placed in the box, normally with rated data 10-36 / 0.4 kV.

The low voltage side of the transformer supplies a low voltage switchgear 8 with a plurality of switches 9 which are placed in a housing 21. The housing can be designed similar to the cable cabinets that normally exist today. Connected to the housing is a ventilation device 10 which comprises one or more fans for ventilating the heat losses from the transformer in the transformer housing.

From the low-voltage switchgear, low-voltage cables 11 emanate which supply different rows of electrical outlets 12 placed on poles at a parking surface 13 containing a plurality of parking windows.

The high voltage switchgear 1 according to Figure 2 contains a switch module 15 which contains a switch 3. The module contains a first measuring and detecting device 4a for triggering short-circuit faults. The module also contains a second measuring and detecting device 4b for triggering short-circuit faults. The devices are connected to the low-voltage switchgear by means of a signal cable 16 for power supply and information exchange with the low-voltage switchgear. In one embodiment of the invention, the devices include a microprocessor and a memory for storing data and software.

The high-voltage switchgear is connected to a high-voltage cable 2 which, in terms of connection, runs straight through the switch module 15. In the example shown, the incoming cable 2a is connected to the switch module in a cable connection 17.

According to the invention, the construction volume of the high-voltage switchgear is concentrated, whereby the construction height can be made small. The high-voltage switchgear is enclosed in a housing 14 which can be a sheet metal structure or a composite structure of sheet metal and concrete. By sheet metal is meant here both a sheet of metal or plastic. By placing parts of the switchgear under the ground surface 18, a further reduction of the construction height is obtained. The parts of the switchgear that need to be serviced are placed behind openable doors 19 in the enclosure 14. The small format and the possibility of placing the switchgear in a way that is not harmful to nature means that building permits can be avoided.

An embodiment of the transformer system 6 is shown in figure 3. In a box 25 of concrete or equivalent material which may be site-built or prefabricated, the transformer module 7 is placed below ground level 18. The box is provided with a lid 26 containing an inspection hatch 20. The low voltage switchgear 8 is in the example shown placed in a housing 21 which is common to the transformer ventilation 10. The switchgear is accessible via a hatch 22 and the ventilation through a grille 23. In the example shown, the low voltage cables 11 are placed below the ground surface 18 in a protective pipe 24.

An exemplary embodiment of a power supply system with a plurality of electrical sockets for connection to a plurality of electric cars is shown in Figure 4. A cable cover 30 which in the example shown is formed with a crescent-shaped casing of a durable material. The protection must withstand, among other things, injury and collision. The cable protection can consist of a plurality of modules 41 which are joined together with joints 31 and fastened to the base with external fastening devices 32. In one embodiment the cable protection is fastened with an internal fastening device 33. The fastening devices can be fastened to the base with screw or nail connection . By attaching the cable cover to the parking surface, digging is avoided, which results in a cost saving.

In the example shown, the cable guards form the foundation for a plurality of posts 35, each of which carries its own connection module 36 with at least one socket. In one embodiment, the connection module contains at least four sockets. Each post is provided with an adjusting device 37 with which the post is adjustable to a vertical position. In one embodiment, the connection module has two outlets covered, each with a lockable door 38. The example shown also contains a payment and control module 39 through which a customer can pay or identify himself with, for example, a credit card. Payment can also be made via the Internet or by payment via mobile phone subscription. In one embodiment, the low-voltage switchgear 8 and the control module 39 are housed in the same housing. The module also contains means for wireless communication, with which the electrical outlets can be controlled or information obtained from, for example, a mobile phone. In the example shown in 534 5249, an electrical outlet contains a reader 40 for a credit card or the like, whereby the payment and control module can be omitted.

The electrical sockets 12 are designed with one or more socket luminaires and a device for controlling both charging current and any additional heat in the car. In one embodiment, the electrical outlet is de-energized as long as no plug is in the outlet. This is to prevent fingras from touching live parts of the socket and to prevent uncontrolled energy consumption. When the plug is plugged into the socket and the power supply is activated by the driver, voltage is switched on at the same time as a locking device prevents the socket from being plugged out or access to the electrical sockets. The system is designed so that locking devices release in the event of a general power failure.

The driver activates the charge by using a credit card, SMS code, code lock or other device. This can be done with the help of a mobile phone or at an activation machine 39. At the same time as the activation, measurement is started as a basis for charging for the common parking / charging service. The measurement, which can consist of time measurement, energy measurement or both, is terminated when the connection is deactivated by the driver. Debiting takes place by invoicing via the telephone bill or in a similar way or by debit on a credit card. The heat outlet can be activated by means of SMS and mobile phone, timer or in a similar way.

Since relatively heavy pressure points are located in existing urban and residential areas, it is advantageous to place the transformer close to the sockets. It is also advantageous to introduce equipment that takes up little space. This is especially important where a building permit is required. Therefore, the T-connection from the 10kV cable is not larger than an enlarged cable cabinet.

The transformer is placed underground while the low voltage is in a standard cable cabinet. The conditions for obtaining a general building permit thus increase markedly. The parking has a lower priority than the rest of the 534 524 loop by feeding it radially, but in the event of a fault it trips before the loop, both for overcurrent and for directional earth fault. No battery or other auxiliary power is needed. The cables for 10kV are not dimensioned by load without short-term current.

Claims (1)

534 524 Ii PATE NTKRAV 1. Installation for distribution of electricity to a plurality of electrically parked electric vehicles on a parking area (13) comprising a plurality of electrical outlets (12), a low-voltage switchgear (8) connected to the electrical outlets, a transformer connected to the low-voltage switchgear ( 7), and a high-voltage switchgear (1) connected to the transformer for connection to a cable-fed power grid (2), characterized in that the transformer (7) is located adjacent to the parking surface, that the high-voltage switchgear is located adjacent to the power grid, that the high-voltage switchgear and the transformer is separated from each other so that a distance occurs between them, and that the high-voltage switchgear is connected to the transformer with a high-voltage cable (5). Plant according to claim 1 or 2, wherein the high-voltage switchgear (1) comprises a T-branch comprising a switch (3) which trips in a shorter time than other switches in the power grid. Plant according to one of the preceding claims, wherein the high-voltage switchgear (1) is partly located below the ground surface (18). Plant according to one of the preceding claims, wherein the transformer (7) is located below the ground surface. Plant according to one of the preceding claims, wherein the plant comprises a box (6) which houses the transformer (7). Plant according to claim 5, wherein the low-voltage switchgear (9) is located on top of the box. 534 524/2 / Plant according to any one of the preceding claims, wherein at least one electrical socket (12) comprises a cable cover (30), a post (35) supported by the cable cover, and a connection module (36) supported by the post containing at least a socket connected to the low-voltage switchgear with an electrical cable (11). Method for distributing electricity to a plurality of parking spaces (13), temporarily parked electric vehicles comprising a plurality of electrical outlets (12) and a transformer station comprising a plurality of electrical outlets (12), a low voltage switchgear (8) coupled to the electrical outlets, one to the low voltage switchgear connected transformer (7), and a high voltage switchgear (1) connected to the transformer for connection to a wired power supply (2), known. e c k n a t a v that the transformer (7) is placed adjacent to the parking surface (13), that the high voltage switchgear is placed adjacent to the power grid, that the transformer and high voltage switchgear are separated so that a distance between them is formed, and that the high voltage switchgear is connected to the transformer with a high voltage cable (5). Method according to claim 8, wherein the high-voltage switchgear is connected to the power grid with a T-branch, and that the T-branch is made to comprise a switch (3) which is tripped in a shorter time than other switches in the power grid. Use of a plant according to claims 1 to 7, or a method according to claim 8 or 9 for charging batteries to an electric vehicle at a municipal or private car park, thereby ensuring a sufficient energy supply.