FIELD OF INVENTION
This invention relates to an improved solar grid hybrid subsystem used with power backup systems.
PRIOR ART
Backup systems are commonly employed to supply reliable power to one or more electrical loads during power failure. Backup system stores energy, typically within a collection of batteries and delivers the stored energy to the electrical loads during a period of time when power from the primary power source, typically the electric power grid, is not available. The collection of battery is used to store energy in the uninterruptible power supply.
Photovoltaic devices are used to generate electrical power from the ambient light. Photovoltaic devices are commonly used to power consuming loads such as lighting, heating, or to operate communications equipment. Photovoltaic devices may also be directly connected to the grid via a grid-connected backup system.
Backup systems are sometimes characterized by their efficiency at converting from AC power to DC power and DC power to AC power. A higher efficiency implies less wasted energy, less heat generated by the process and greater financial savings. Similarly, photovoltaic applications are also often characterized by their efficiency at converting light to useful electrical energy. Higher efficiency implies a better use of the capital dollars expended to install the photovoltaic system.
Power backup systems are also characterized by the duration of their ability to deliver energy in a form and manner suitable for use by a load in the event of a power failure.
Reference may be made to the following citations:-
US Publication No. 2010019577 relates to the solar power kits for uninterruptible power supplies and related methods. The uninterruptible power supply includes a power bus, mains circuitry configured to rectify electrical energy received from a mains supply system into rectified electrical energy and to provide the rectified electrical energy to a power bus of the uninterruptible power supply, photovoltaic circuitry configured to convert solar energy into converted electrical energy and to provide the converted electrical -energy to the power bus, a battery system configured to receive electrical energy from the power bus to charge a battery of the battery system and to discharge electrical energy to the power bus, an inverter configured to provide electrical energy from the power bus to the load, and a controller configured to monitor the photovoltaic circuitry and to implement at least one operation of the uninterruptible power supply using the monitoring.
US2010060229 discloses portable PV modular solar generator. Plurality ofwheels are attached to the bottom of a rechargeable battery container. At least one rechargeable battery is contained inside the rechargeable battery container. A power conditioning panel is connected to the rechargeable battery container. At least one photovoltaic panel is pivotally connected.
Publication No. JP2009016785 is directed to the solar photovoltaic portable generation unit which is always easy to carry. The system comprises a case main body and a lid body of the case house solar panels. A battery which is charged with power generated by the respective solar panels, a controller for controlling the charge to the battery and an inverter for converting the power charged to the battery into an alternating current to feed the alternating current to the outside are fixed to the inside of the case main body. The case main body is provided with a receptacle for power supply electrically connected to the inverter and a handle for carrying the case. The solar panel is fixed to the case main body while covering the battery, the controller and the inverter.
Publication No. CN1070290 pertains to the multifunctional controller for solar electric generating equipment which is composed of photovoltaic silicon array, automatic charge regulator circuit, automatic distribution circuit, automatic power supply controller circuit, voltage-stabilizing circuit, DC output and protecting circuit, alarm circuit, lagging battery treating and emergency power supply, inversion circuit, two sets of battery, casing, panel and rear cover. The electric energy output from solar photovoltaic silicon array is fully and reasonably stored in battery sets in a certain manner and the battery set is controlled to continuously supply stabilized DC voltage to load.
US Patent No. 7,072,194 discloses a power conversion system adapted to provide continuous power to single or multiple phase AC loads when fed from separate DC and single or multiple phase AC sources.
US Patent No. 7,479,774 discloses an automatic control, electronics, DC-DC conversion, DC-AC conversion and energy technology, specifically, solar photovoltaic (PV) energy conversion system being used in power grid.
Publication No. CN201194333 is directed to a novel solar energy photovoltaic grid-connected system.
US Publication No. 20100208501 relates to management of power transfer from a local power source to a load that is tied to a utility power grid.
US Publication No. 20100246230 discloses a solar photovoltaic source feeding into an enhanced DC-DC power converter providing a smoothed DC output to a photovoltaic DC-AC inverter that may perhaps ultimately interface with a grid.
All the above mentioned prior arts provide backup system where the grid power is directly supplied to the backup system. As a result, the backup system will bypass the available grid power to load with or without regulation and incase of failure or abnormality of the grid power it provides the power through the external or internal batteries or charge storage device. Solar power can't be interfaced with such systems directly.
In view of the above mentioned prior arts, the present invention provides solar grid hybrid subsystem which can be connected with the power backup systems and works on the basis of the user's defined priorities of the available source of power like Grid, Solar, batteries or charge storage device and controls the charging of the batteries from grid or solar power or both and AC and DC load simultaneously.
OBJECTS OF THE INVENTION
The principal object of the present invention is to provide an improved solar grid hybrid subsystem which acts as an interface device for supplying power to the backup systems.
Another object of the present invention is to provide an improved solar grid hybrid subsystem used with power backup systems which is configured by user and user has options to set the priority of the source of the power as per requirement.
Still another object of the present invention is to provide an improved solar grid hybrid subsystem used with power backup systems to protect the power backup system from deteriorating effects of voltage & frequency fluctuations.
Yet another object of the present invention is to provide an improved solar grid hybrid subsystem used with power backup systems that can be configured to utilize the optimum/maximum power available through the solar power.
Another object of the present invention is to provide a system that is used to control the battery charging through solar or grid power or both and AC and DC load simultaneously.
Still another object of the present invention is to provide an improved solar grid hybrid subsystem used with power backup systems that is used to measure and monitor (locally or remotely) the power consumed by power backup systems to
run the AC load/charging of batteries and DC load, power generated through the solar panels and various states of the power backup systems and battery status and health etc.
Still another object of the present invention is to provide a flexible, cost effective and efficient system for power backup systems.
SUMMARY OF THE INVENTION
Accordingly the present invention provides an improved solar grid hybrid subsystem which controls the charging of the external batteries or charge storage device either through solar power available through the PV panels or power backup system by controlling the input power flow into power backup system. User can configure the solar grid hybrid subsystem and set the priority of the source of the power as per requirement. Solar grid hybrid subsystem controls the battery charging through solar or grid power or both and AC and DC load simultaneously.
In an embodiment of the present invention, the solar grid hybrid subsystem is connected between the photovoltaic array, AC grid and the power backup system.
In another embodiment of the present invention, the DC power source from the photovoltaic array and AC power source from the AC grid is first fed into the solar grid hybrid subsystem.
In yet another embodiment of the present invention, the solar grid hybrid subsystem provides necessary protection at the input of the backup system to protect the power backup system from any voltage & frequency fluctuations.

In still another embodiment of the present invention, the battery is charged through the power backup system or directly through the solar grid hybrid subsystem.
In another embodiment of the present invention, the output of the power backup system is fed back to the solar grid hybrid subsystem.
STATEMENT OF INVENTION
According to this invention, there is provided an improved solar grid hybrid subsystem for power backup system comprises atleast one photovoltaic panels, a DC-to-DC converter coupled with the photovoltaic panels, contactor and interface circuitry configured to couple with a power bus of power backup system, backup system and battery connected to each other wherein, the power from photovoltaic array or AC grid is fed to the solar charge controller and backup system.
BRIEF DESCRIPTION OF THE ACCOMPANYING DRAWING
Further objects and advantages of this invention will be more apparent from the
ensuing description when read in conjunction with the accompanying drawing and
wherein:
FIG. 1 shows a functional block diagram of an improved solar grid hybrid subsystem according to the present invention
DETAIL DESCRIPTION OF THE INVENTION WITH REFERENCE TO THE ACCOMPANYING DRAWING:
Reference may be made to fig.l, wherein the solar grid hybrid subsystem is implemented with photovoltaic circuitry therewithin. The system is configured for use with existing power backup systems which do not include photovoltaic
circuitry and its control of power utilization. The solar grid hybrid subsystem includes atleast one photovoltaic panels, a DC-to-DC converter coupled with the photovoltaic panels, contactor and interface circuitry configured to couple with a power bus of power backup system. The user interface is provided in the system so that the user defines the priority of the available source of power such as but not limited to the grid, solar batteries or charge storage device and controls the charging of the batteries from grid or solar power or both and AC and DC load simultaneously.
This system of the present invention comprises at least three energy sources: the photovoltaic DC source, which supplies energy when available; the battery, which acts as energy storage, accepting energy from the photovoltaic source or the AC grid during emergency; and the AC grid, which provides energy either to charge the battery or supply to loads.
The system of the present invention involves a solar photovoltaic source feeding into solar grid hybrid subsystem providing a smooth and uniform DC output to a battery/charge storage device connected with power backup system. Ultimately, the power backup system inverts the DC and creates an AC output which is established as an input to a domestic electrical system or some other power consuming device.
The power is first fed to the solar grid hybrid subsystem. The solar grid hybrid subsystem first monitors the power of the incoming AC and controls the input AC power from source to deliver safe and permissible power at the backup system's input. The solar grid hybrid subsystem in this way protects the backup system from deleterious effects of voltage & frequency fluctuations.
The system allows power from the utility grid when the sunlight is insufficient to generate enough electricity to power all the electrical loads. In this case, the power from the utility grid is used to supply power to the electrical loads and to recharge the battery. The system can also operate independently from the grid.
The surplus power from the photovoltaic array is used to charge the battery or to run the electrical load connected at the output of the power backup system by controlling the input mains power flow to backup system. The battery can be charged through the backup system or directly through the solar grid hybrid subsystem.
The system is programmed to monitor and control its functions based on load and demand parameters and available energy resources. The solar grid hybrid subsystem is also configured for either on solar or battery or grid or mix of any two power sources priorities. The system is used to measure and monitor (locally or remotely) the power consumed by power backup systems to run the AC load/charging of batteries and DC load, power generated through the solar panels and various states of the power backup systems and battery status and health etc.
It is to be noted that the present invention is susceptible to modifications, adaptations and changes by those skilled in the art. Such variant embodiments employing the concepts and features of this invention are intended to be within the scope of the present invention, which is further set forth under the following claims:-

WE CLAIM:
1. An improved solar grid hybrid subsystem for power backup system comprises atleast one photovoltaic panels, a DC-to-DC converter coupled with the photovoltaic panels, contactor and interface circuitry configured to couple with a power bus of power backup system, backup system and battery connected to each other wherein, the power from photovoltaic array or AC grid is fed to the solar charge controller and backup system.
2. The improved solar grid hybrid subsystem as claimed in claim 1, comprising of an user interface to set the priority as per the requirement.
3. The improved solar grid hybrid subsystem as claimed in claim 1 or 2, wherein the solar grid hybrid subsystem provides safe and permissible power at the input of the power backup system to protect the backup system from any voltage fluctuation.
4. The improved solar grid hybrid subsystem as claimed in any of the preceding claims, wherein the battery is charged through the backup system or directly through the subsystem.
5. The improved solar grid hybrid subsystem as claimed in any of the preceding claims, wherein the output of the power backup system is fed back to the solar grid hybrid subsystem.
6. The improved solar grid hybrid subsystem as claimed in any of the preceding claims, wherein said power backup system is inverter, uninterruptible power supply, Home UPS or secondary storage device.
7. The improved solar grid hybrid subsystem as claimed in any of the preceding claim, wherein said system measures and monitors (locally or remotely) the power consumed by power backup systems to run the AC load/charging of batteries and DC load, power generated through the solar panels and various states of the power backup systems and battery status.
8. The improved solar grid hybrid subsystem as claimed in any of the preceding claims, wherein said solar grid hybrid subsystem is configured for either on solar or battery or grid or combination of any two power sources priorities.
9. An improved solar grid hybrid subsystem for power backup system substantially as herein described with reference to the accompanying drawing.