Description:Complete Specification:

The following specification describes and ascertains the nature of this invention and the manner in which it is to be performed.
Field of the invention
[0001] This invention is related to a bi-directional power charging device.

Background of the invention
[0002] Currently, owners of EVs who also solar installation have have to install an inverter for inverting DC supply from Solar to AC and then use AC to charge their car. Bi-directional charging capability is currently not existing in the market that can also be connected to solar inverter. The above-mentioned problem is solved in the present invention with a unified product (component) that could integrate different DC/AC inverters, DC-DC converters. Such a solution would offer better opportunity for energy cost optimization in homes and buildings. The overall requirement (numbers) for converters is reduced in total. Seamless bi-directional charging that couples solar and EV is possible.

[0003] A US patent 9302590 discloses a solar station for charging vehicles. The invention answers the need for the existence of a network for charging electric vehicles (EV), particularly with regard to the so-called fast charging (20 to 30 minutes). Therefore, this station is intended for, inter alia, parking areas of public and private buildings, and fossil fuels service stations, such places where the slow charging is not very viable, since this type of charging (6 to 8 hours) will be done mostly at night. The present invention envisages the charging of EVs within a short period of time and with the particularity of being renewable energy produced on site, being possible to produce in one place the electrical energy necessary to power the EVs, since it includes structures of photovoltaic panels and equipment for the transformation of energy and the fast charging of the existing DC batteries in the EVs.
 
Brief description of the accompanying drawings
[0004] Figure 1 illustrates a bi-directional power charging device, in accordance with an embodiment of the invention.

Detailed description of the embodiments
[0005] Figure 1 illustrates a bi-directional power charging device, in accordance with an embodiment of the invention. The device 10 comprises a power source selector 12 adapted to change a path of the power and a bi-directional converter 14 connected to the power source selector switch 12. The bi-directional converter 14 converts the power from one form to another form. The device 10 further comprises a converter 16 and a bi-directional cable 18 connected to the converter 16, adapted to charge a battery 20 of a vehicle 21 directly from a solar unit 22.

[0006] Further the construction of the bi-directional power charging device 10 and the components of the power charging device 10 is explained in detail. The power source selector 12 is connected to a power path coming from a grid unit 28. Depending on an operational state of the device 10, the power source selector12 continues or discontinues the flow of the power from the grid unit 28. In addition, power source selector 12 is connected to a bi-directional AC-DC converter and enables the flow of power from solar unit 22, battery 20 of a vehicle 21 and to stationary battery 30 to grid unit 28 or building unit 26. The power source selector12 is chosen from a group of switches comprising a MOSFET, an IGBT, a bi-polar junction transistor and the likes. However, the type of switch is not restricted to above, but can be any other type that is known to a person skilled in the art. The power source selector 12 comprises multiple switches (as shown in the figure 1) for changing the path of the power. According to one embodiment of the invention, the converter 16 is a DC-DC converter.

[0007] The bi-directional converter 14 coverts a direct current (DC) power to an alternating current (AC) power and vice-versa (i.e.., from AC to DC or from DC to AC) depending on the requirement. For instance, for powering a battery 20 of a vehicle 21 from the grid unit 28, the bi-directional converter 14 converts the incoming AC power to a DC power and the same is provided to the battery 20 for charging via a DC-DC converter 16. And in another instance, if a building unit 26 is to be powered from the battery 20 of the vehicle 21, then the bi-directional converter 14 converts the DC power from the battery 20 of the vehicle 21 via a DC-DC converter 16 to the AC power. According to one embodiment of the invention, the vehicle 21 is an electric vehicle.

[0008] According to one embodiment of the invention, the converter 16 is a DC-DC converter, which is connected between the solar unit 22, the battery 20 of the vehicle 21 and a stationary battery 30. The device 10 having this converter 16 directly charges/powers the vehicle battery 20 of the vehicle 21 from the solar unit 22 via the bi-directional cable 18. The bi-directional cable 18 connects the device 10 and the battery 20 of the vehicle 21, charges the battery 20 of the vehicle 21 from any one of the sources the grid unit 28, the solar unit 22 and the stationary battery 30. For instance, when the battery 20 of the vehicle 21 is to be charged from the solar unit 22 via the DC-DC converter 16, then the cable 18 is used charging the battery 20 of the vehicle 21 using the DC power. In another instance, when the battery 20 of the vehicle 21 is to be charged from the grid unit 28 via the AC-DC bi-directional converter 14 and the DC-DC converter 16, then the cable 18 is used to charge the battery 20 using the DC power.

[0009] The device 10 comprises an energy optimizer 24 adapted to manage the power from and to the battery 20 of the vehicle 21 based on a requirement. The energy optimizer 24 manages and optimizes the usage of the power that involves the grid unit 28, the building unit 26 and solar unit 22. I.e., the energy optimizer 24 upon detecting a need of the power to be powered to the building unit 26 in addition to the grid unit 28 to reduce peak building load, re-directs the power from the battery 20 of the vehicle 21 to the building unit 26 via the DC-DC converter and the AC-DC bi-directional of power charging device 10. And also, if the energy optimizer 24 upon detecting a requirement of charging a backup battery 30, then the power is directed either from the solar unit 22 or from the grid unit 28 via AC-DC converter 14 and DC-DC converter 16. In another instance, at least one unit of power is transmitted back to the grid unit 28 from the battery 20 of the vehicle 21 for optimizing the overall energy cost by selling power to grid during peak hours.

[0010] A method of working of the device 10 is explained in detail. When the power is received from the grid unit 28, the power source selector12 allows the AC power from the grid unit 28 directly to building unit 26. When the power from the grid unit 28 is used to charge the battery 20 of the vehicle 21 directly, then the AC-DC bi-directional converter 14 present in the device 10 is used to convert the AC power of the grid unit 28 to a DC power and DC-DC converter 16 to level the DC power to the battery 20 voltage for charging.

[0011] In addition to the above mentioned, when the power is receiving from the solar unit 22, then the device 10 charges the battery 20 of the vehicle 21 via the DC-DC converter 16 and the bi-directional cable 18. The DC power from the solar unit 22 is directly used to charge the battery 20 of the vehicle 21. And also, when the power is required to manage the building unit 26 (during a power outage or needed of additional power), then the energy optimizer 24 re-directs the DC power from the battery 20 of the vehicle 21 or solar unit 22 or stationary battery 30 to the building unit 26 via the DC-DC converter 16, the AC-DC bi-directional converter 16 and the power source selector 12. The same method is applied, when there is a requirement to optimize the energy cost, when the power from the battery 20 of the vehicle 21 is transmitted back to the grid unit 28.

[0012] From the above-mentioned bi-directional power charging device 10, one can charge the battery 20 of the vehicle 21 directly from the solar unit 22 via the DC-DC converter 16 and the bi-directional cable 18. The energy optimizer 24 forecasts of the building consumption demand and controls the charging behavior of the electric vehicle 21. The energy optimizer 24 ensures that the peak sanction load is not exceeded. The device 10 provide a seamless connection between the solar unit 22 and the battery 20 of the vehicle 21 charging in addition to optimizing energy consumption of the building 26 electrical appliances.

[0013] Device 10 eliminates redundancy in converters/inverters to utilize solar power for vehicle battery 20 charging. The Device 10 reduces number of power conversions there by reducing power losses. Further device 10 allows to eliminate the need for bi-directional DC/AC converter inside the vehicle 21 thereby facilitating wider adoption of bi-directional charging. AC wall-mount charger is not required to charge the vehicle 21 with the above disclosed device 10.

[0014] It should be understood that embodiments explained in the description above are only illustrative and do not limit the scope of this invention. Many such embodiments and other modifications and changes in the embodiment explained in the description are envisaged. The scope of the invention is only limited by the scope of the claims.
, Claims:We Claim:

1. A bi-directional power charging device (10), said device (10) comprising:
- a power source selector (12) adapted to change a path of said power;
- a bi-directional converter (14) connected to said power source selector (12), adapted to convert said power from one form to another form;
characterized in that:
- a converter (16); and
- a bi-directional cable (18) connected to said converter (16), adapted to charge a battery (20) of a vehicle (21) directly from a solar unit (22).

2. The device (10) as claimed in claim 1, comprises an energy optimizer (24) adapted to manage said power from said battery (20) of said vehicle (21) based on a requirement.

3. The device (10) as claimed in claim 2, said energy optimizer (24) re-directs said power from said charged battery (20) to any one of the following power lines comprising a building unit (26), a grid unit (28).

4. The device (10) as claimed in claim 1, wherein said bi-directional cable (18) connecting said device (10) said battery (20) of the vehicle (21), charges said battery (20) of said vehicle (21) from any one of the sources solar unit (22) or grid unit (28).

5. The device (10) as claimed in claim 1, wherein said bi-directional converter (14) adapted to convert said power from an alternating current (AC) to a direct current (DC) and vice-versa and said converter (16) is a DC-DC converter.

6. The device (10) as claimed in claim 1, wherein said bi-directional converter (14) adapted to convert DC power from said converter to AC power for powering said building unit (26) and said AC power to said DC power for charging said battery (20) of said vehicle (21).

7. The device (10) as claimed in claim 1, wherein said vehicle (21) is an electric vehicle.