APPARATUS AND METHOD FOR CHARGING ELECTRIC VEHICLES

Abstract: A device and a procedure for recharging of an electric vehicle's (25) energy storage units (20, 21). The device includes a charging unit (15) for conversion of mains distributed electrical energy to an for the vehicle's storage units adapted electrical energy. The device also includes means (17) for measuring features of the mains distributed electrical energy, means (18) to detect recharging needs in the vehicle storage units (20, 21) and a control unit (16) for controlling the charging unit (15), which is dependent on input data from the measuring means (17) and the detecting means (18). Owing to that the mains distributed electrical energy's features are measured, that the recharging needs in the vehicle storage units (20, 21) are detected and that the recharging is directed dependent on input data from the measuring means (17) and detecting means (18), the recharging process can be adapted to the features of the available electric power and to charging requirements in the vehicle storage units.

Description: i "Apparatus and method for charging electric vehicles" TECHNICAL AREA The present invention refers to a device for recharging the energy storage units of a vehicle, primarily a electric vehicle, comprising a charging unit for conversion of mains distributed electrical energy to an electrical energy which is adapted to the vehicle storage units. The invention also refers to a procedure for recharging the electric vehicle. BACKGROUND OF THE INVENTION A electric vehicle is provided with rechargeable batteries that need regular recharging with electrical energy. Besides energy is needed for the vehicle's support apparatuses, for example climate system and temperature control of batteries. The number of electric vehicles in the traffic will increase and this implies an increased load onto the electric distribution mains in the long run. A problem in connection to this, is that more electrical energy is consumed during the cold period of the year to recharge a electric vehicle, when at the same time the electricity consumption for heating of households is high. It is therefore desirable that the distribution of energy for recharging electric vehicles is done in such a way that said load is optimized. From a international point of view, it is desirable that an electric vehicle shall be capable of being recharged with different occurring current variations, for example with a voltage from a single-phase of 100 volt to a three-phase of 415 volt and with frequencies of 50 Hz up to 60 Hz. Besides, function disturbances that influences the loading, for example phase disappearance and power intermission, should be minimized. Further, an extended recharging period with lower current can give the batteries of an electric vehicle added life. THE PURPOSE AND MOST IMPORTANT FEATURES OF THE INVENTION The purpose of the present invention is therefor to achieve a device for recharging vehicles, for example electric vehicles that fulfil the above given needs. For this purpose, the device according to the invention is characterized in; means for measuring features of the mains distributed electrical energy, means for detection of charging needs in storage units of the vehicle and a control unit for controlling the charging unit, which is depending on input data from the measuring means and the detecting means. By means of this design of the device, electric vehicles can be recharged anywhere in the world and make good use of the available effect of the electric mains for an optimal utilization. Further the electric distributor can deliver its current with a more uniform power-distribution over twenty-four hours. SHORT DESCRIPTION OF THE DRAWINGS The invention will be described herebelow with reference to the embodiment that is shown in the enclosed drawings, in which: Fig. 1 shows a device according to the invention schematically as a block diagram, and Fig. 2 shows a distribution system for electrical energy in a corresponding way. DESCRIPTION OF EMBODIMENT In Fig. 1 the reference numerals 10, 11 and 12 indicate the three phases in a distribution mains for three-phase alternating current, while 13 and 14 indicate the zero and ground of the mains respectively. These conductors are in a conventional way parts in a common cable that is connectable by means of suitable connector means to a built-in charging unit 15 in a non shown electric vehicle, which charging unit is suitably constructed by switch-technique and is controlled by a control circuit 16. The control unit 16 is connected to a measurement circuit 17 which among other things senses the voltage in the different phases 10-12 and sends its measured data to the control unit 16, which in its turn regulates the charging unit 15, so that accessible energy is utilized optimally without overload of the power mains. Suitably, the measurement circuit 17 also includes a transmitter and a receiver for communication via the power mains according to known technique. The control unit 16 is also connected to a detecting circuit 18, which via electronics in the vehicle senses the requirements in the vehicle loads, for example batteries, heat storage, cooling storage or other support apparatuses, whereby the charging process can be optimized via the control unit with regard to input data from the detecting circuit 18. A keyboard 19, which is connected to the control unit 16, can be used to enter data manually, for instance regarding the power mains capacity, the nominal current of the fuse, available effect at different times a day. Besides the keyboard can be used for input of data regarding date for the next use of the vehicle, whereby the battery recharge can be controlled so that the best charge status of the batteries 20 and eventual heat- and cooling storage 21 are achieved just before the vehicle shall be used. In this way losses in the storage units can be avoided. The above described device can be complemented by providing a nearby house with a local load detector on the power mains, which sends data about available electric energy (deducted from main fuses) to the measurement transmitter and receiver of the circuit 17. The communication via the power mains can also be utilized in such a way that the electricity distributor announce accessible effect both central and local, which is illustrated in Fig. 2 where the reference numeral 22 indicates one central electricity distributor, 23 local electricity distributors, 24 dwelling-houses or recharging stations and 25 electric cars that are connected. With this form "of distribution, a favourable uniform load on a power-plant can be achieved over twenty-four hours. With gathered information from several different electric vehicles priorities can also be given with reference the individual needs. This can be developed very far with information from vehicle drivers, on for example driving distances and starting time. Further, input data from the circuit 18 can also be included, for example about the cars normal driving cycle, time and date. As the vehicle can send information regarding its need and thereby indicating its identity, it can also be connected to a debit system for the energy bought. Above said system can be extended so that a vehicle can receive an energy increase in principle by each parking occasion. The existing power mains only needs to be changed in an relatively small extent. The invention is not limited to the above described embodiments, instead more variants are conceivable within the scoop of following claims.

Claims: CLAIMS 1. Device for recharging the energy storage units (20, 21) of a vehicle, primarily a electric vehicle (25), comprising a charging unit (15) for conversion of mains distributed electrical energy to an electrical energy which is adapted to the vehicle storage units, c h a r a c t e r i z e d i n, means (17) for measuring the features of the mains distributed electrical energy, means (18) for detection of recharging needs in the storage units (20, 21) of the vehicle and a control unit (16) for controlling the charging unit (15), which is depending on input data from the measuring means (17) and the detecting means (18). 2. Device according to claim 1, c h a r a c t e r i z e d i n, that the control unit (16) includes means (19) for manual input of data regarding the mains distributed energy. 3. Device according to claim 1 or 2, c h a r a c t e r i z e d i n, that the measuring means (17) includes a transmitter and a receiver for reception of information regarding available electric power and distribution between respective phase. 4. A method for recharging the energy storage units (20, 21) of an electric vehicle (25), comprising conversion of mains distributed electrical energy to an electrical energy adapted to the vehicle storage units, c h a r a c t e r i z e d i n, that the features of the mains distributed electrical energy are measured, that the recharging needs of the vehicle's storage units (20, 21) are detected and that the charging is controlled in dependence to input data from measuring means (17) and detecting means (18), in such a way that the charging process is adapted to the features of the available electric power and to the recharging needs of storage units in the vehicle. 5. A method according to claim 4, c h a r a c t e r i z e d i n, that the recharging need for the vehicle (25) is adapted to respective storage units' (20, 21) individual needs. 6. A method according to claim 5, c h a r a c t e r i z e d i n, that the recharging of the vehicle (25) is adapted to data regarding driving cycles, time of day, day of the week and date. 7. A method according to any of claims 4 - 6, c h a r a c t e r i z e d i n, that the recharging process is optimized with regard to the time-span to the next using-occasion and driving-distance/stop- time of the vehicle (25). 8. A method according to claim 7, c h a r a c t e r i z e d i n, that data regarding the vehicle's approximated energy requirements are sent to the measuring device (17), which by means of two-way communication via the electric mains responds with data about the appropriate power outlet, based on other local input data, for example the twenty-four hours consumption of electricity in a nearby house (24). 9. A method according to claim 8, c h a r a c t e r i z e d i n, that several sockets placed in a local group, and several vehicles within this group, share the local electrical energy available for the group with individual needs priority. 10. A method according to claim 9, c h a r a c t e r i z e d i n, that data regarding available electric energy are distributed via a central electric distributor's electric mains, for control of the recharging of the group of vehicles and for equalization of the power load on the distribution mains. 11. A method according to claim 10, c h a r a c t e r i z e d i n, that identification data on the individual electric vehicle are transmitted via the electric mains for use at debit of the energy costs. 12. A method according to claim 11, c h a r a c t e r i z e d i n, that identification data on a user of a electric vehicle (25) are also transmitted via the electric mains for use at debit of energy cost and any rent for the vehicle. AMENDED CLAIMS [ received by the International Bureau on 28 February 1994 (28.02.94); original claims 1 - 12 replaced by amended claims 1 - 12 ( 3 pages)] 1. A vehicle energy recharging system, primarily for energy storage units (20, 21) in an electric vehicle (25), comprising a charging unit (15) for conversion of mains distributed electrical energy to energy which is adapted to the vehicle storage units, c h a r a c t e r i z e d in means (17) for detecting and measuring the features of the mains distributed electrical energy, means (18) for detection of recharging needs in the storage units (20, 21) of the vehicle, and a control unit (16) for controlling the charging unit (15), said control unit being adaptable to input data from the measuring means (17) and the detecting means (18). 2. A recharging system according to claim 1, c h a r a c t e r i z e d in that the control unit (16) includes means (19) for manual input of data regarding the mains distributed energy. 3. A recharging system according to claim 1 or 2, c h a r a c t e r i z e d in that the measuring means (17) includes a transmitter and a receiver for reception of information regarding available electric power and distribution between respective phase. 4. A method for recharging the energy storage units (20, 21) of an electric vehicle (25), comprising conversion of mains distributed electrical energy to an electrical energy adapted to the vehicle storage units, c h a r a c t e r i z e d in that the features of the mains distributed electrical energy are measured, that the recharging needs of the vehicle's storage units (20, 21) are detected and that the charging is controlled in dependence to input data from measuring means (17) and detecting means (18), in such a way that the charging process is adapted to the features of the available electric power and to the recharging needs of storage units in the vehicle. 5. A method according to claim 4, c h a r a c t e r i z e d in that the recharging need for the vehicle (25) is adapted to respective storage units' (20, 21) individual needs. 6. A method according to claim 5, c h a r a c t e r i z e d in that the recharging of the vehicle (25) is adapted to data regarding driving cycles, time of day, day of the week and date. 7. A method according to any of claims 4 - 6, c h a r a c t e r i z e d in that the recharging process is optimized with regard to the time-span to the next using- occasion and driving-distance/stop-time of the vehicle (25). 8. A method according to claim 7, c h a r a c t e r i z e d in that data regarding the vehicle's approximated energy requirements are sent to the measuring device (17), which by means of two-way communication via the electric mains responds with data about the appropriate power outlet, based on other local input data, for example the twenty-four hours consumption of electricity in a nearby house (24). 9. A method according to claim 8, c h a r a c t e r i z e d in that several sockets placed in a local group, and several vehicles within this group, share the local electrical energy available for the group with individual needs priority. 10. A method according to claim 9, c h a r a c t e r i z e d in that data regarding available electric energy are distributed via a central electric distributor's electric mains, for control of the recharging of the group of vehicles and for equalization of the power load on the distribution mains. 11. A method according to claim 10, c h a r a c t e r i z e d in that identification data on the individual electric vehicle are transmitted via the electric mains for use at debit of the energy costs. 12. A method according to claim 11, c h a r a c t e r i z e d in that identification data on a user of a electric vehicle (25) are also transmitted via the electric mains for use at debit of energy cost and any rent for the vehicle.

Inventors: SVEDOFF GOERAN, SVEDOFF, GOERAN
Applicants: SVEDOFF GOERAN, VOLVO AB, AB VOLVO
Application year: 1993
Main classification: H02J3
IPC codes: B60L11, H02J3, H02J7