WO2021152483A1

WO2021152483A1 - A charging system and method for ultra-fast supercapacitor-to-supercapacitor charging for electric vehicles

Info

Publication number: WO2021152483A1
Application number: PCT/IB2021/050645
Authority: WO
Inventors: Riho KOOP
Original assignee: Oü Skeleton Technologies Group
Priority date: 2020-01-28
Filing date: 2021-01-28
Publication date: 2021-08-05
Also published as: GB2591464A; GB202001153D0

Abstract

An ultra-fast charging system for supercapacitor-to-supercapacitor charging for electrical vehicles comprising a rechargeable vehicle accumulator unit is intended for rapid charging of supercapacitor-based vehicle energy storage systems while minimizing fluctuations in power demand from the grid and minimizing the size of AC/DC converters needed. This is accomplished by predictive charging of the supercapacitor pack(s) of the charging station (101) while the vehicle in end route to the charging station. Vehicle transmits state of charge data, temperature, average energy consumption, average speed and other relevant metrics to the charging station. These data are used to update the incoming vehicle model to determine the optimum state of charge for charging station supercapacitor pack(s).

Description

A charging system and method for ultra-fast supercapacitor-to-supercapacitor charging for electric vehicles

Field of Invention

The subject matter of the present invention pertains in general to rapidly charging supercapacitor-based accumulators in vehicles. The invention describes a method for ultra-fast supercapacitor-to-supercapacitor charging for electric vehicles and a charging station with a novel design using the ultra-fast charging method. The solution of charging station is intended for ultra-fast charging of supercapacitor-based energy storage systems of vehicles while minimizing fluctuations in power demand from the grid and minimizing the size of AC/DC converters needed.

Background of invention

Fast chargers for electric vehicles today use AC/DC converters to provide energy to charge the accumulator. Peak power for the charging event is mostly dependent on the maximum power output of the converter and the capability of the grid supplying the converter. A high-power converter and in many cases an upgrading of the grid supplying the converter are needed. These requirements make installation of new charging stations very expensive and in many locations impossible because of power grid limitations.

Document US2010/0026248A1 (US8,482,263B2, 9.07.2013), 4.02.2010, Philippe, Barrade (US) et al. describes a method of using a charger containing supercapacitors to charge a supercapacitor powered device. The method uses a DC/DC to limit the current during energy transfer from the charger supercapacitors to the supercapacitors of chargeable device. This approach gives no efficiency or cost benefits compared to using an AC/DC converter to charge the supercapacitors of chargeable device.

Document WO2008/125766A2, 23.10.2008, Peugeot Citroen Automobiles SA describes a method and device for recharging the electric energy storage of a vehicle including a battery. A method comprises dividing storage into at least two electric energy storage modules, connecting serially said modules during the use for supplying electric energy and connecting in parallel modules for recharging the storage using the battery. Document US2014/0266004A1 , 18.09.2014, Zevtron, LLC describes a charging management system, comprising a controller; and a memory storing instructions configured to be executed by the controller to cause the charging server to perform the steps of: connecting to a charging server; connecting to an authorization management system; receiving a charging request from a charging server, the charging request identifying an electric charging device requested to be used to charge an electric vehicle; transmitting an authorization request to the authorization management system for the electric charging device to be used to charge the electric vehicle; receiving an authorization response from the authorization management system authorizing the electric charging device to be used to charge the electric vehicle; and transmitting an authorization instruction to the charging server to charge the electric vehicle using the electric charging device.

Document US2016/0167678A1 , 16.06.2016, Blue Solutions, describes a transport facility, comprising an electrical vehicle with connection means for connection of the storage module with supercapacitor to a source outside the vehicle, and a recharging station for recharging the vehicle positioned on a path of the vehicle and in the vicinity of which the vehicle is intended to stop. The recharging station being connected to the energy source and including connection means mating the first connection means of the vehicle, and capable of electrically connecting the or one of the energy sources to the first storage module with supercapacitor.

Thus, the current state of art lacks a method for rapidly charging the electric vehicles with low requirements to power grid and a low-cost charging station.

Summary of invention

The solution described in present application is intended for rapid charging of supercapacitor-based vehicle energy storage systems while minimizing fluctuations in power demand from the grid and minimizing the size of AC/DC converters needed. This is accomplished by predictive charging of the supercapacitor pack(s) of the charging station 101 while the vehicle in end route to the charging station 101. Vehicle transmits state of charge data, temperature, average energy consumption, average speed and other relevant metrics to the charging station. These data are used to update the incoming vehicle model to determine the optimum state of charge for charging station supercapacitor pack(s). Power levels of the AC/DC converters are adjusted to provide minimum variation in load to grid. Low average power draw from the grid compared to conventional fast charging solutions enables installing the chargers for instance in areas where city grid capability is not sufficient for traditional fast chargers. Reducing the size of AC/DC converters by an order of magnitude and with no need for upgrading city grid capability reduces the two largest variables in total installation cost.

Brief description of the drawings

The description below provides detailed information on a method and a charging station according to the invention. The invention should not be viewed to be limited to the specific descriptions of the embodiments in this paragraph. The detailed description is accompanied with drawings where:

Fig 1 illustrates general overview of an ultra-fast charging system, shown are main components of the system - an ultra-fast charging station connected to the city electrical grid and an electrical vehicle accumulator unit. All components framed in dashed line are optional parts of the system;

Fig 2 illustrates the main power electronics of an ultra-fast charging station;

Fig 3 illustrates main components of a vehicle accumulator unit according to the present invention;

Fig 4 illustrates in general the flow chart of a vehicle arrival state prediction;

Fig 5 illustrates the control and monitoring units of the ultra-fast charging system, showed is an overview of the main functions of the charging station control and monitoring system 103 and the vehicle accumulator control and monitoring system 104;

Fig 6 illustrates ultra-fast charging system behaviour and working principle;

Fig 7 illustrates a detailed charging step according to the method of present invention;

Fig 8 illustrates the pre-charging phase algorithm steps according to the method of present invention;

Fig 9 illustrates the charging phase algorithm steps according to the method of present invention;

Fig 10 illustrates the by-passable current limiting resistor 109 with bypass switch of the ultra-fast charging unit. Detailed description of the invention

In fig 1 is illustrated general overview of an ultra-fast charging system 1 comprising an ultra-fast charging station 101 connected to the electrical power grid 105, for example city electrical power grid, and via charging connector unit 111 to an electrical vehicle accumulator unit 102.

An ultra-fast charging system for supercapacitor-to-supercapacitor charging for electrical vehicles comprising a rechargeable vehicle accumulator unit (102) is based on ultracapacitors or battery systems with comparable internal resistance to ultracapacitor based accumulator systems or combination of both.

The vehicle accumulator unit 102 comprises vehicle input protection unit 112 consisting of high-side and low-side switches (e.g., solid-state or electromechanical) and a fuse, and vehicle supercapacitor pack(s) 113. The vehicle input protection unit 112 monitors the input voltage and protects vehicle accumulator unit is controlled by vehicle control and monitoring unit 103.

An ultra-fast charging station 101 comprises as main component an AC/DC converter(s) 106, supercapacitor pack(s) 107, voltage level selectors(s) 108 and a charging station control and monitoring unit 103. In alternative embodiment, the ultra fast charging station 101 comprises as main component an AC/DC converter(s) 106, supercapacitor pack(s) 107, a voltage level selectors(s) 108, a current limiting resistor 109 with or without bypass switch, a main output switch 110 and a charging station control and monitoring unit 103.

The main power electronics of an ultra-fast charging station, shown in Fig 2, are supercapacitor pack(s) 107, voltage level selector(s) 108, by-passable current limiting resistor(s) 109 and main output switch(es) 110. There are different placement options for the by-passable current limiting resistor(s) 109 (which may be high-side, low-side or both).

The by-passable current limiting resistor(s) 109 can be placed in high-side, in low- side or in both sides. 109A shows high-side placement, where the by-passable current limiting resistor(s) are placed on DC “+” side and 109B shows low-side placement, where the by-passable current limiting resistors are placed on DC side. Both the high-side and low-side placements can be included in the system simultaneously or separately. Placement of the by-passable current limiting resistor(s) 109 is not dependant on the placement of the main output switch(es). The figure illustrates placement options for the main output switch(es) 110 (which may be high- side, low-side or both), 110A shows high-side placement, where main output switch(es) 110 are placed on DC “+” side and 110B shows low-side placement, where the main output switch(es) 110 are placed on DC side. Both the high-side and low-side placements can be included in the system simultaneously or separately. Placement of the main output switch(es) 110 is not dependant on the placement of the by-passable current limiting resistor(s) 109.

The main components of a vehicle accumulator units 102 (see fig 2) are main components for a typical supercapacitor-based accumulator: input protection 112 consisting of high-side and low-side switches (e.g., solid-state or electromechanical) and a fuse, and vehicle supercapacitor pack(s) 113.

The by-passable current limiting resistor 109 with bypass switch of the ultra-fast charging unit is shown in fig 10. The purpose of the current limiting resistor is to limit peak current during the charging cycle of the electrical vehicle accumulator unit 102. In the by-passable current limiting resistors 109, the resistor 1091 can be bypassed by bypass switches 1092 (shown in fig 2 and fig 9). Bypass switches are actuated by the controller of the charging station control and monitoring unit 103. Bypass switches used can be electromechanical or solid-state switches.

Vehicle accumulator control and monitoring system monitors the SOC, temperature and balancing of supercapacitor packs, controls and monitors the contactors. The relevant data is transmitted to the charging station control and monitoring system 103 via data connection 114. Charging station control and monitoring system 103 receives data via data connection 114 from the vehicle accumulator control and monitoring system 104 and uses it together with state information from network converter(s), supercapacitor pack(s), voltage level selector(s), by-passable current limiting resistor(s), main output switch(es), current sensor(s), insulation monitoring device (IMD) to control all subsystems of the charging station 101.

Main components of ultra-fast charging station:

AC/DC converter(s)

The ultra-fast charging station 101 is connected to the electrical power grid via AC/DC converter(s) 106. The AC/DC converter provides power to supercapacitor pack(s) 107 when required by the control algorithm of the charging station control and monitoring unit 103. The ultra-fast charging system is optimised to use the AC/DC converters to provide power to supercapacitor packs as constantly as possible to minimise fluctuations in electrical power grid demand and minimise the power requirement of the AC/DC converters giving maximum cost saving and placing minimum requirements on the electrical power grid. Placing low requirements on electrical power grid enables placing charging stations in locations where building traditional fast-charging stations would require extensive upgrades of the electrical power grid.

Supercapacitor pack(s)

Supercapacitor pack(s) 107 accumulate energy from the electrical power grid and provide energy for the charging cycle. Depending on system specification 1 to n (1+n) number of supercapacitor packs can be used to achieve the necessary charging characteristics of the ultra-fast charging station. All supercapacitor packs don^'t necessarily have the same configuration of parallel and series supercapacitors, depending on the system design specifics.

Voltage level selector(s)

1 to n (1+n) number of switching devices as voltage level selectors 108 providing the function of giving output from the supercapacitor packs 107 at different voltage levels are used. Voltage level selectors used can be electromechanical or solid-state switches.

By-passable current limiting resistor(s) and main output switch In alternative embodiment of the ultra-fast charging station, depending on system requirements a number of current limiting resistors 109 can be used in the system. The purpose of the current limiting resistor is to limit peak current during the charging cycle of the electrical vehicle accumulator unit 102. In the current limiting resistors 109, the resistor 1091 can be bypassed by bypass switches 1092 (shown in fig 2 and fig 9). Bypass switches are actuated by the controller of the charging station control and monitoring unit 103. Bypass switches used can be electromechanical or solid- state switches. Current limiting resistors can be connected to the +DC (high-side) 109A of the voltage level selector 108 or to GND (low-side) 109B of the supercapacitor pack 107. In addition to the current limiting resistors 109, a main output switch 110 governs the energy flow from the ultra-fast charging station through charging connector unit 111 to the electrical vehicle accumulator unit 102 of the electrical vehicle arrived to the ultra-fast charging station 101. Main switch 110 is actuated by the controller of the charging station control and monitoring unit 103. Main switch used can be electromechanical or solid-state switch. Main switches 110 can be connected either to the high-side 110A current limiting resistor (see fig 2 by-passable current limiting resistor 109A) and/or to the low-side 110B current limiting resistor (see fig 2 by- passable current limiting resistor 109B). When the ultra-fast charging system 1 is configured without main switches 110, the voltage level selector 108 must be dimensioned for switching under high current operation in order to act as both the voltage level selector 108 and main switch 110.

Controller of the charging station control and monitoring unit

Controller of the charging station control and monitoring unit 103 or multiple such control units working together govern the functioning of all other system components of the ultra-fast charging station 101 based on ultra-fast charging system inputs.

Main ultra-fast charging system inputs from the ultra-fast charging station 101 are: ultra-fast charging station supercapacitor pack(s) 107 voltage(s), temperatures of the charging station components, for example, temperature of AC/DC converter, supercapacitor pack, charging station, etc., IMD (Insulation Monitoring Device for monitoring resistance between DC+ and earth and DC- and earth to give an alert and disconnect the power supply when resistance between system and earth drops below a predetermined value, for example, below 50kQ) state, voltage level selector 108 state (open or closed), by-passable current limiting resistor 109 state (passed or by-passed), main output switch 110 state (open or closed), charging station output current, charging connector unit state (connected or not connected). The needed actions are calculated by software algorithm of the computer program adapted for charging station control and monitoring unit and corresponding commands are sent to ultra-fast charging system components.

Predictive algorithm is used to estimate the incoming electrical vehicle accumulator state when the vehicle arrives at the ultra-fast charging station (see fig 4). Based on the accumulator state data transmitted from the electrical vehicle, the state estimate is updated. The predictive algorithm also takes into account the historical data on energy usage and driving time to increase accuracy of the estimate. Based on the state estimate, optimal voltage levels for the charger supercapacitor packs are calculated and AC/DC converters are controlled accordingly. Data transmitted by the vehicle to the ultra-fast charging system are for example: position (GPS coordinates or etc.) and speed of the vehicle for calculation estimated time of arrival to the station, accumulator state of charge (SOC), accumulator temperature, auxiliary power demand. Same time the system obtains and uses data provided by third-party service providers, for example Waze, Google Maps, to improve estimation accuracy. The data can include weather, arrival estimation, traffic jams, accident alerts.

In addition, the charging system uses relevant historic data on previous trips completed on the same route under similar conditions, aimed to improve estimation accuracy. For example, trip time, average speed, energy consumption, SOC at arrival to charging station, previous estimation accuracy, as well route terrain, environmental data or other relevant data of the route the vehicle is travelling on, for example, elevation profile, number of turns and traffic junctions, outside temperature, precipitation.

Arrival time and SOC prediction algorithm

There are many suitable options for Arrival time and SOC prediction, the optimal approach depends on the use case and data availability. Deep learning algorithms, for example artificial neural networks are very suitable for handling the large number of inputs of this system. Tree-based, linear, Fuzzy-logic, Model Based Predictive control (MPC) and probabilistic algorithms can accomplish the same task.

Target voltage and target charging power calculator

Based on the SOC estimate at arrival, supercapacitor pack(s) voltages of the charging station are optimised to not exceed maximum current rating during charging while providing necessary charging speed and amount of energy needed for recharging the accumulator of the electrical vehicle.

Based on the arrival time estimate, necessary charging power is calculated for the supercapacitor pack(s) to reach optimal voltage level when the electrical vehicle arrives at the ultra-fast charging station. Corresponding commands are sent to AC/DC converter(s) 106 by charging station control and monitoring unit 103. Charging connector unit

Purpose of the charging connector unit 111 is to connect and disconnect the charging stations output to the charging system of electrical vehicle accumulator unit in need of charging vehicle supercapacitor pack(s) 113. Charging connector unit 111 can be a plug and socket type, i.e., for example the ultra-fast charging station has plug connected to voltage level selector or in alternative embodiment to current limiting resistor or main output switch, surface-to-surface mating type, sliding type, clamping type. The connection is made by a pantograph system, sliding rail system, spring loaded system, pneumatic system, hydraulic system, electrical actuator system, electromagnetic system, robotic arm system, 2D CNC (Computer Numerical Control) system, 2.5D CNC system, 3D CNC system N-D CNC system, depending on system requirements.

Chargeable device

Chargeable device is a supercapacitor pack based electrical vehicle accumulator, specifically the rechargeable vehicle accumulators based on ultracapacitors, battery systems with comparable internal resistance to ultracapacitor based accumulator systems or combination of both.

Vehicle control and monitoring unit 104 transmits vehicle accumulator supercapacitor pack state information or projected charging need beforehand to the ultra-fast charging station 101 by using wireless communication technology so that the ultra fast charging station has time to adjust the voltage levels of its supercapacitor pack(s) 107 to match the charging need before electrical vehicle arrives to the ultra-fast charging station. All known wireless communication technologies can be used involving transmitters and receivers of radio waves, antennas both in the electrical vehicle and at charging station and necessary hardware and software for transmitting/receiving/processing information and data.

Vehicle state data (for example speed, average energy consumption, auxiliary load, accumulator temperature, accumulator SOC), third-party service provider data, historic data, route terrain, environmental data are combined in an algorithm to calculate arrival SOC prediction and arrival time. Based on these two results target voltage levels and target power levels are calculated for the AC/DC converters 106. The targets are periodically updated as the vehicle nears the charging station to have the charging station 101 supercapacitor pack(s) 107 at the correct voltage for optimum charging performance

Operating procedure of the ultra-fast charging system

Operating procedure can simplistically split into two steps: pre-charging and charging phase.

Pre-charging

Pre-charging phase (as shown in fig 8) begins with charging request transmission from the next electrical vehicle arriving to the ultra-fast charging station 101 and having chargeable device, i.e. , supercapacitor pack based electrical vehicle accumulator 102 to be charged. Chargeable device state data or charging need estimate is transmitted from the vehicle accumulator unit to the ultra-fast charging station. Data transmission can be point-to-point via cellular network, long range Wi-Fi, Bluetooth, narrowband loT (Internet of Things). Alternatively, the vehicle can have an internet connection via cellular network modem, Wi-Fi link to an internet access point, Bluetooth link to an internet access point, narrowband loT link to an internet access point. In this case the data is routed to a server, which the charging station accesses to retrieve the data. Ultra-fast charging station connection to the internet could be a landline or cellular network connection. Based on the constantly updated data from the incoming electrical vehicle and historical data about trip time and energy consumption accumulator state at the time of arrival is estimated and constantly updated. Ultra-fast charging station 101 begins adjusting the voltage level in its supercapacitor packs 107 to the provided optimum charge profile to the next accumulator of the chargeable device of the electrical vehicle to be charged.

When electrical vehicle reaches the ultra-fast charging station 101 and charging station supercapacitor packs 107 have reached the necessary voltage levels, the electrical vehicle accumulator unit 102 is connected to the ultra-fast charging station via charging connector unit 111. Connection quality is validated with connection resistance test of the charging connector and corresponding data are processed in the charging station control and monitoring unit 103. If connection quality is satisfactory and safety critical parameters are within predetermined range, charging phase can begin, else reconnection of the electrical vehicle accumulator unit and ultra-fast charging station is attempted, or pre-charging cycle is aborted. Charging

Charging phase of the vehicle begins with the lowest voltage supercapacitor pack 107 of the ultra-fast charging station being discharged to the vehicle supercapacitor pack 113 of the electrical vehicle accumulator unit 102. For this, the voltage level selectors 108 of ultra-fast charging station 101 as switching devices are switched so that the first voltage level is selected, for example 300V (see levels fig 6). After the appropriate switching has confirmed to have taken place by charging station control and monitoring unit 103, the main output switch 110 of charging station is made conductive. This can occur through the current limiting resistor 109 included in the charging system of the alternative embodiment or without depending on ultra-fast charging system configuration. If current limiting resistor 109 is used, the charging begins through the current limiting resistor to limit initial current peak caused by a large voltage difference between the voltage of the ultra-fast charging station 101 supercapacitor pack 107 and the voltage of vehicle supercapacitor pack as energy storage unit. When the charging current drops below a predetermined setpoint the current limiting resistor is bypassed. For this, the main output switch 110 is made unconductive (see fig 2), bypass switching device 1092 (see fig 2, 9) is made conductive, effectively bypassing the resistor 1091 of the current limiting resistor 109, after confirmation of the action taking place the main output switch 110 is made conductive again and charging of the vehicle continues with the next voltage level, for example 400V. All switches are controlled and monitored by charging station control and monitoring unit 103. Confirmation of the change in switching devices state can be had with contact following relay in case of electromechanical switching device being used or with a feedback signal from the power semiconductor driver circuit or power semiconductor driver IC (Integrated Circuit) to the charging station control and monitoring unit 103.

After the current has dropped again to a predetermined setpoint, main output switch is made unconductive again. Switching devices are configured again to give the next voltage level, for example 500V, by engaging the next supercapacitor pack in series with the previous pack of the ultra-fast charging station. Charging again continues as described in the previous steps, firstly through the current limiting resistor (in alternative embodiment) then by bypassing the current limiting resistor. Again, if the current drops below a predetermined level, the next voltage level, for example 600V, is selected as described previously. This continues until all supercapacitor packs of the ultra-fast charging station have been used or vehicle supercapacitor pack (accumulator) has reached predetermined level of saved energy, i.e. predetermined level of voltage.

Thereafter the electrical vehicle accumulator unit 102 is disconnected from the ultra fast charging station 101. After disconnecting is confirmed by vehicle control and monitoring unit and charging station control and monitoring unit, the electrical vehicle leaves and ultra-fast charging station is ready to accept data from the next electrical vehicle arriving to the charging station.

In Fig 6 is illustrated ultra-fast charging system behaviour and working principle, shown are example of a working system current and voltage with by-passable current limiting resistors where ultra-fast charging system uses seven voltage levels, where each voltage level is discharged to the vehicle accumulator first through the current limiting resistor 109 until the control algorithm estimates that charging current without limiting resistor would be within safe limits, the by-passable current limiting resistor 109 is bypassed, resulting in a rise in current and efficiency and reduction in charging time. Once the current has dropped again below a current limit determined by the control algorithm, the next voltage level is selected, and charging is continued again firstly through the current limiting resistor;

In Fig 7 is illustrated a detailed charging step according to the method of present invention. Shown is example of one voltage level being used in charging process. (A) shows the main output switch 110 being made conductive. (B) shows current limiting resistor 109 bypassed. (C) shows current limiting resistor 109 unbypassed, the next voltage level selected by making the previously used voltage level selector 108 SW_1 unconductive, the next voltage level selector 108 SW_2 conductive and main output switch 110 made conductive, resulting in the next voltage level being used for vehicle accumulator 102 charging;

In Fig 8 are illustrated the pre-charging phase algorithm steps according to the method of present invention. Using the data from the incoming vehicle, incoming vehicle arrival state prediction is used to calculate target voltage(s) for the charging station 101 supercapacitor pack(s) 107. According to these targets the voltages of supercapacitor pack(s) 107 are adjusted by the AC/DC converter(s) 106. Arrival state prediction and the resulting voltage and charging power targets are periodically updated as up to date data is transmitted from the incoming vehicle. When the vehicle has arrived at the charging station and supercapacitor pack(s) 107 of charging station 101 have reached the target voltage(s) mating of the charging contacts between the vehicle and station is attempted. If the connection is successful it is possible to continue to charging phase. In case of an unsuccessful mating, the mating is retried;

In Fig 9 are illustrated the charging phase algorithm steps according to the method of present invention. At the beginning of the charging phase the voltage level selectors 108 are configured to output the lowest (first) voltage level by having the first voltage level selector 108 SW_1 in a conductive state and the other voltage level selectors

108 in an unconductive state. The by-passable current limiting resistor(s) 109 are in an unbypassed state. The main output switch 110 is closed (made conductive), completing the circuit between supercapacitor pack(s) 107 of the charging station 101 and supercapacitor pack(s) 113 of the vehicle accumulator 102. As the voltages equalise, the current drops. When the current reaches lower threshold calculated by the control algorithm to be safe to continue operation without the current limiting resistor, the main output switch is opened (made unconductive). The by-passable current limiting resistor(s) 109 is bypassed by making the switching device 1092 conductive. Main switch is closed again. As current drops again below the lower threshold limit calculated by the control algorithm to be suitable for the next charging step, the main output switch 110 is opened. By-passable current limiting resistor(s)

109 are set in unconductive state again. If all charging station 101 supercapacitor packs 107 were used (in series) for the charging step (i.e. , the voltage level selector 108 SW_n is in conductive state and the rest of the voltage level selectors are in unconductive state) the charge cycle is finished. If all charging station 101 supercapacitor packs 107 were not used for the charging step (i.e., the voltage level selector other than 108 SW_n is in conductive state and the rest of the voltage level selectors are in unconductive state), the next voltage level selector is made conductive and the rest unconductive, effectively adding the next supercapacitor pack to the series and raising the voltage for the next charging step. The charging procedure is repeated until all supercapacitor packs 107 of charging station 101 are used (i.e., the voltage level selector 108 SW_n is in conductive state and the rest of the voltage level selectors are in unconductive state) then the charge cycle is finished; 1 - ultra-fast charging system

101 - ultra-fast charging station

102 - electrical vehicle accumulator unit

103 - charging station control and monitoring unit 104 - vehicle control and monitoring unit

105 - electrical power grid

106 - AC/DC converter

107 - supercapacitor pack

108 - voltage level selector 109- current limiting resistor

1091 - resistor

1092 - bypass switch

110 - main output switch

111 - charging connector unit 112 - vehicle input protection unit

113 - vehicle supercapacitor pack

Claims

1. An ultra-fast charging system for supercapacitor-to-supercapacitor charging for electrical vehicles comprising a rechargeable vehicle accumulator unit (102) comprising a vehicle control and monitoring unit (104) and a vehicle supercapacitor pack (113) to be charged, and a separate ultra-fast charging station (101) connected to an electrical power grid (105) and comprising an AC/DC converter (106) connected to the electrical power grid to provide energy to a supercapacitor pack (107) of ultra-fast charging station, a charging station control and monitoring unit (103), a voltage level selector (108) connected to the supercapacitor pack (107) to provide the function of giving output from the supercapacitor packs at different voltage levels, a charging connector unit (111 ) to enable the energy flow from the ultra-fast charging station (101) through said unit to the vehicle accumulator unit (102) of the electrical vehicle arrived to the ultra-fast charging station (101).

2. The ultra-fast charging system according to the claim 1 where the vehicle accumulator unit (102) comprises in addition a vehicle input protection unit

(112) connected to the vehicle supercapacitor pack (113) and controlled by vehicle control and monitoring unit (103).

3. The ultra-fast charging system according to claim 1 or 2 where charging station comprises in addition a current limiting resistor(s) (109) with bypass switch(es) (1092) to limit initial current peak caused by a large voltage difference between the voltage of the supercapacitor pack (107) of the ultra fast charging station (101) and the voltage of the vehicle supercapacitor pack

(113), and a main output switch (110) to enable the energy flow from the ultra fast charging station (101 ) through a charging connector unit (111 ) to vehicle supercapacitor pack (113) of the electrical vehicle accumulator unit (102) of the electrical vehicle arrived to the ultra-fast charging station.

4. The ultra-fast charging system according to claim 3 where the main output switch(es) (110) is controlled by the charging station control and monitoring unit (103) and connected either to high-side (110A) of the voltage level selector (108) and/or to low-side (110B) of the supercapacitor pack (107) of the ultra-fast charging station (101). 5 The ultra-fast charging system according to claim 3 where the current limiting resistor(s) (109) with bypass switch(es) (1092) controlled by controller of the charging station control and monitoring unit (103) are connected to the high- side (109A) of the voltage level selector (108) or to low-side (109B) of the supercapacitor pack (107) of the ultra-fast charging station (101).

6. A method of ultra-fast charging for electrical vehicles implementing the ultra fast charging system according to claims 1-5 where charging procedure has been split into a pre-charging phase and a charging phase, where

- the pre-charging phase begins with a charging request transmission from an electrical vehicle arriving to the ultra-fast charging station (101) and having a supercapacitor pack based electrical vehicle accumulator (102) to be charged, wherein o vehicle supercapacitor pack state data or charging need estimate is transmitted using wireless communication technologies from the vehicle accumulator unit to the ultra-fast charging station, said transmitted data contain vehicle position, speed, accumulator state of charge (SOC), accumulator temperature, auxiliary power demand for calculation of estimated time of arrival to the ultra-fast charging station and vehicle accumulator SOC at arrival, data provided by third-party service providers that can include weather, arrival estimation, traffic jams, accident alerts to improve estimation accuracy;

- the pre-charging phase continues with an adjusting the voltage level in supercapacitor packs (107) of the ultra-fast charging station to provide pre determined charge profile to the vehicle supercapacitor pack of the electrical vehicle arriving to the ultra-fast charging station;

- the charging phase begins when the electrical vehicle reaches the ultra fast charging station (101), charging station supercapacitor packs (107) have reached the predetermined voltage levels and a mating of the charging contacts between the vehicle and station is successful, thereafter o the electrical vehicle accumulator unit (102) is connected to the ultra-fast charging station via charging connector unit (111) and connection quality is validated with connection resistance test of the charging connector and corresponding data are processed in the charging station control and monitoring unit (103), o when the connection quality is validated and safety critical parameters are within predetermined range, charging phase can begin, else reconnection of the electrical vehicle accumulator unit and ultra-fast charging station is attempted or pre-charging cycle is aborted,

- the charging phase starts with the lowest voltage level supercapacitor pack (107) of the ultra-fast charging station being discharged to the vehicle supercapacitor pack (113) of the electrical vehicle accumulator unit (102), thereafter the next voltage level supercapacitor pack is discharged to the vehicle supercapacitor pack, said process is repeated until the pre determined voltage level of the vehicle supercapacitor pack is reached.