Field of the Invention:

This invention related to a circuit is prepared in which the DC power would be converted into AC in stepped up form. Moreparticularly, this circuit contradicts the in used method of power transformation which would require several intermediate steps and a transformer, thus making it to be more economical and simpler way of power generation. This invention related that is used is advanced form of H-bridge inverter made of four MOSFETs. The triggering of these MOSFETs is controlled by pulse generator and a NOT gate. The voltage is stepped up by the help of capacitor and then fed to the grid through auto synchronizer so that the frequency can be maintained as per the IE rule.

Background of the invention:

The ancestral or the pre-existing method of energy generation leads to tremendous global warming and air pollution. The key to combat these climatic changes lies in the uses of renewable sources of energy. Solar energy is one such example of renewable source of energy. Though the demand of solar energy is at its peak but the method used for generation of power from it is not up to the mark and has several snags. This project helps to overcome some of the drawbacks of generating power through solar energy in a more convenient way.
Power is injected to the bus bar at the grid connection of solar photovoltaic (PV) system from its AC output. For successful power transmission the bus bar must synchronize with the AC source. We use this circuit to eliminate the use of transformer and intermediate circuit and many intermediate steps in grid connected solar photovoltaic system. It is used to synchronise the values of power parameters of grid with that of solar photovoltaic automatically. Protection Relay is used to protect the system from voltage surges. The control system as developed in the circuit uses the feedback from the Grid.

The document US20110298305A1 We describe a photovoltaic (PV) power generation system comprising at least two PV panels and a power conditioning unit. The dc power outputs of the PV panels are connected in parallel to a dc power input of the power conditioning unit. The power conditioning unit comprises a dc-to-dc converter having an input coupled to the dc power input and an output coupled to a dc link of the unit, a dc-to-ac converter having an input

coupled to the dc link and an ac mains power supply output, and an energy storage capacitor coupled to the dc link. The power conditioning unit is configured to perform maximum power point tracking (MPPT) responsive to a level of power flowing into the dc power input, and the level of power flowing into said dc power input is sensed at the dc link. In preferred implementations the energy storage capacitor is a non-electrolytic capacitor.

The document US6329589B1 A solar panel arrangement for capturing solar energy and supplying power for use in a building. Solar cells are embedded in a window pane and generate electrical direct current that is converted, by an electrical circuit permanently attached to the pane, to an oscillating current that is fed to a ferrite core mounted to the pane. An external ferrite core is mounted in close proximity to the core, so that the oscillating current can be picked up and supplied to a building. The arrangement allows window panes to be pre-formed or manufactured with certain built-in electrical components, and, without the need for skilled labor, to be easily connected to a power circuit external of the window pane.

The document WO2016135508A1 A Solar Home System comprises photovoltaic panels (1), rechargeable batteries (2), a system controller (3) and one or more loads and provides an intelligent and adaptive operation. This operation optimises the solar charging and then adjusts the output for each device on the system to match predicted usage patterns that are developed by tracking typical usage.

The document US7479774B2 The present invention focuses on the development of a high-performance solar photovoltaic (PV) energy conversion system. The power circuit of the invention is made of a two-stage circuit, connecting a step-up DC-DC converter and a full-bridge inverter in serial. The present invention uses an adaptive perturbation and observation method to increase tracking speed of maximum power position and at the same time reduces energy loss. In addition, the full-bridge inverter's output has to have the same phase with the utility power in order to achieve unit power factor and increase the system efficiency. The present invention uses voltage type current control full-bridge inverter to achieve the goal of merging into utility grid. The present invention provides an active Sun tracking system, by utilizing the character of changing in open circuit output voltage with Sun radiation strength to follow the Sun, and decreases the system cost and increases system effectiveness.

The document WO2017049373A1 a THERMOPHOTOVOLTAIC (TPV) SOLAR PANEL WITH HYBRID COCONUT FIBER, the world has a new way of generating solar energy, specifically an invention by Fernando Cesar Uma Alves Ximenes (Ceará, Brazil) that forms a monolithic hybrid smart solar unit, a solar module able to generate solar energy from two solar sources (photovoltaic and thermal) at the same time and instantaneously, developed using coconut fibre, a widely available renewable plant energy source, and silicon. Furthermore, the module stores 22 litres of water in the radiator cell, internal, serpentine copper coils with a cold-water inlet and a hot-water outlet made of stainless steel pipes on the sides, automatically converts direct current into alternating current, stores electricity and couples the system to a 200-liter water storage tank with continuous heating. The efficiency and capacity of the TPV module enable same to power lighting and electric/electronic devices of electricity consumers, while also providing hot water, providing an alternative to the use of electric showers and other industrial thermal water-heating systems. By producing electricity, providing storage and heating water continuously, the TPV invention can be used as an alternative to other energy sources for generating electricity and heating water, such as: natural gas and oil, satisfying the energy needs of homes, businesses, industry, hospitals and other consumers that use electricity and hot water. Furthermore, the economy and efficiency of the invention cannot be matched by any other solar system seen before in the world, and could be accessible to anyone, from people in low-income social groups involved in social-housing schemes to high-income individuals and other commercial and industrial energy users. This will help the invention to become widely used, promoting environmental sustainability using clean renewable fuel. The invention does not emit any toxic liquid or gas waste, thereby helping to slow global warming.

The document WO2014024200A1 A device for continuous indoor/outdoor illumination of directly from Solar Panel is provided. The device includes a native DC current to drive LED lights, an Auto Grid Control and PV Panel Switcher array of two Relay Switches wherein one of the Relay Switches is co-located with the Solar Panels for toggling on/off solar input in case of periodic or intermittent low solar insulation below an acceptable adjustable threshold, which in turn triggers the 2nd Relay Switch co-located with the set of luminaire to seamlessly switch over to the grid or solar, thus catering for inadequacy or erratic solar insolation.

Summary of the invention

Photovoltaic cell generates DC voltage which is a linear voltage. The output linear voltage reaches to be connected into sinusoidal ac voltage. This requires series of converter and a transformer for proper connection with the grid. The synchronization is also required. So as to maintain proper source to load power transfer. This whole conventional process includes
several conversion devices and transforms which deduces the cost effectiveness of system. Moreover manual synchronizer requires skilled manpower and more workforces. In this project the inverter that is replaced by advanced form of H-bridge inverter made of four MOSFETs. The triggering of these MOSFETs is controlled by pulse generator and a NOT gate. The voltage is stepped up by the help of capacitor and then fed to the grid through auto synchronizer so that the frequency can be maintained as per the known standards.

Detailed description of the invention with accompanying drawings:

This project consist of some power electronics devices that helps to obtain a regulated ac output without using a transformer. This transformer is replaced by an auto-synchroniser and a modified H-bridge made of MOSFET. In Fig 1 the block diagram of conventional method of power transfer is shown in which there are several conversions are shown. The DC voltage wave is converted into pulsating DC voltage wave and then it is inverted to ac wave. This ac voltage is then stepped up using a transformer so that it can be connected to a grid network.
Fig.2 shows the proposed method of voltage conversion in which a MOSFET based bridge network is implemented so as to convert the dc voltage directly to step up ac voltage. The MOSFETs are triggered at 50% duty cycle. Two MOSFETs are triggered at one cycle and rest two in other. A NOT gate is connected to the pulse generator so as to maintain the alternate triggering mechanism of the advanced H bridge [4]. Capacitors are connected at the load end so as to filter the waveform. The rating of the inductors and capacitors are according to the required voltage output.
The voltage transformation ratio is given by:-

?? = 45
???? 116

Auto synchronizer mechanism as shown in Fig.2 contains voltage sensing unit which senses the voltage in the grid side and provides the voltage data to the microcontroller. The microcontroller processes the data as received from the sensing unit. The microcontroller compares the voltage of the grid side with the input side and regulates the voltage in the following logic:-
V1 - input voltage before dc to ac conversion. V2 - grid voltage.
If,V2>V1, voltage is boosted up. If,V2