[0001] Inventors: SUDHIR KUMAR, RAM BEER SINGH [0002] FIELD OF THE INVENTION

[0003] The present invention generally relates to the field of fire extinguisher/fire preventer for electric transformer. The invention, particularly relates to a system for detecting, preventing and/or protecting explosion of an electric transformer equipped with an oil conservator tank filled with combustible coolant fluid. The present invention also describe the method of detecting, preventing and/or protecting explosion of an electric transformer.

[0004] BACKGROUND OF THE INVENTION

[0005] Electrical transformer is a static electrical machine which transforms electrical power from one circuit to another circuit, without changing the frequency. Transformer can increase or decrease the voltage with corresponding decrease or increase in current. The basic principle behind working of a transformer is the phenomenon of mutual induction between two windings linked by common magnetic flux. Basically a transformer consists of two inductive coils; primary winding and secondary winding. The coils are electrically separated but magnetically linked to each other. When, primary winding is connected to a source of alternating voltage, alternating magnetic flux is produced around the winding. The core provides magnetic path for the flux, to get linked with the secondary winding. Most of the flux gets linked with the secondary winding which is called as 'useful flux' or main 'flux', and the flux which does not get linked with secondary winding is called as 'leakage flux'. As the flux produced is alternating and the direction of it is continuously changing, EMF gets induced in the secondary winding according to Faraday's law of electromagnetic induction. This EMF is called 'mutually induced EMF', and the frequency of mutually induced EMF is same as that of supplied EMF. If the secondary winding is closed circuit, then mutually induced current flows through it, and hence the electrical energy is transferred from one circuit (primary) to another circuit (secondary). [0006] Power utilities have installed power substations in their distribution grids to accommodate the ever increasing demand for dependable power with their rows of large high voltage power transformers. Many precautions are taken to safeguard them against failure because when all power fails, customers complain, revenues are lost and medical emergencies can even happen. One of the risks these large transformers are subjected to is fire. Although the manufacturers of these oil filled transformers are building them with many embedded safety features, but when they fail they often produce very large amount of fires that are very difficult to extinguish and provoke environmental damages by the release of thick black toxic smoke and spilling of transformer oil. This is why more and more utilities are installing fire protection systems to protect their investment and to prevent such fires.

[0007] Different types of Transformers are used in power systems. Commonly used power transformer is oil filled power transformer. In the oil filled power transformer oil acts both as insulating and cooling media. During an internal fault resulting in an arc will cause fire. The fire may spread resulting from ignition of oil, causing explosion of tank, rupture of tank, core and winding and also burning the neighboring equipments.

[0008] A number of different type of the tools and methods for fire extinguishing or fire prevention for power transformers are available in the prior art. Prior art document, Indian patent application, 9722/DEL P/2007 discloses a device for preventing the explosion of an electric transformer equipped with a tank filled with combustible coolant fluid, including a pressure relief element to decompress the tank, a reservoir arranged downstream of the pressure relief element and at least one stopper valve on the reservoir such that the reservoir is hermetic in order to collect a fluid that passes through the pressure relief element.

[0009] Another prior art document, Indian patent application, 732/MUM P/2009 discloses a device for prevention against the explosion of a member in an electric transformer comprising a vessel containing a combustible cooling fluid, comprising a pressure relief member for depressurizing the vessel, and a bag provided downstream and capable of expanding from a flat state to an inflated state upon the failure of the pressure relief member for confining the fluid.

[00010] Another prior art document, US6804092 discloses a device for prevention against explosion of an electrical transformer comprising an enclosure filled with combustible coolant, and a means for decompressing the enclosure of the transformer. The decompression means comprises a rupture element with integrated explosion detector provided with a retention part 4 including first zones which have a reduced thickness in comparison with the rest of the retention part and are capable of tearing without fragmenting when the said element 1 ruptures, and second zones which have reduced thickness in comparison with the rest of the retention part and are capable of folding without tearing when the said element ruptures.

[00011] Yet another prior art document, WO2016024267 discloses a fire depression device. The said fire depression device system, which is comprised of the following: a fire extinguisher; solenoid adapted to release said extinguisher; a flexible conduit adapted to direct the contents of the extinguisher to the stove; a linear heat detector for sensing fire; a disconnecting box adapted to disconnect the cooking gas or electricity from stove at the event of fire; a second C02 gas or equivalent gas container that is connected to the disconnecting box; another solenoid adapted to release said gas container; more conduits connected to each of the burners in the stove. In this configuration, fire suppression, and gas cutoff are effected simultaneously.

[00012] Yet another prior art document, Indian patent application, 405/DEL P/2013, which is a divisional patent application of 9722/DEL P/2007 which appears to disclose a device for preventing the explosion of an electric transformer equipped with a tank filled with combustible coolant fluid, including a pressure relief element to decompress the tank, a reservoir arranged downstream of the pressure relief element and at least one stopper valve on the reservoir such that the reservoir is hermetic in order to collect a fluid that passes through the pressure relief element. [00013] Yet another prior art document, Indian patent, IN202302 discloses asystem for preventing, protecting and / or detecting explosion and / or resulting fire of electrical transformer in advance before decomposition of combustible coolant fluid / dielectric oil, said system comprising: one or more differential current sensing electrical relay for calculating the difference of input current and output current with the ceiling level and thereby providing first input to the control unit, if ratio of input current to output current exceeding more than the predetermined limit; wherein said input current and output current are the currents from high voltage conductor and low voltage conductor of the electrical transformer (respectively; one or more buchholz relay for sensing the excessive oil surge in the transformer and thereby providing second input to the control unit.

[00014] Yet another prior art document, CN202044682, which appears to discuss a water spray fire extinguishing system for a transformer, which comprises a fire pump station, at least one or more than one water spray sprinkling pipe, a fire control cabinet and a detecting device, wherein the water spray sprinkling pipe is connected with a main water outlet pipe of the fire pump station, a control processor of the fire control cabinet is connected with a fire pump of the fire pump station and a sprinkler valve of the water spray sprinkling pipe respectively, and the detecting device comprises a linear temperature sensing detector, a temperature probe detector and a three-side switching processor of a main transformer, which are respectively connected with the control processor. The water spray fire extinguishing system has the advantages that by adopting the dual detection of a temperature sensing cable and a temperature sensing probe, not only can the temperature of the main transformer and an oil conservator body be monitored, but also dot-type temperature monitoring can be performed on the connection between the main transformer and a porcelain shell of a high-voltage transformer; simultaneously, a detecting three-side circuit breaker of the main transformer forms a logical relation, thereby solving the problems of false fire alarm of the main transformer and false sprinkling; the structure of the system is simple, the layout is compact, the control is easy and the maintenance is convenient.

[00015] Yet another prior art document,CN102836514 discloses an automatic tracking jet extinguishing systems, fire detection through its real-time front-end detection portion of a dual-band infrared fire detectors, a linear beam smoke detectors and image-type fire detectors, a fire broke out immediately after notification portion control center fire monitoring and management of hosts, fire monitoring and management of the host to determine the ignition point location, start the video-processing equipment and hard disk recorders for the fire situation in real-time video, and immediately drive the associated gun body scan and lock the ignition point, and start the fire pump is electrically controlled by linkage controller total valve and the corresponding coupling member; gun body positioning device and the image of the flame ignition point positioning means for positioning and alignment of the infrared flame after the ignition point, cannon fire pump controller body electrically controlled sprinkler valves were opened.

[00016] Yet another prior art document, CN104217519 discloses a fire alarm robot for transformer substations and inflammable places. The fire alarm robot comprises a transmission system, direct-current motor driving modules, flame sensors, smoke sensors, tracking modules, an ultrasonic module, an active buzzer module, a communication module, a single-chip microcomputer, a remote control module, a power source system and a fixing plate, wherein the direct-current motor driving modules, the flame sensors, the smoke sensors, the tracking modules, the ultrasonic module, the active buzzer module, the communication module, the remote control module and the power source system are connected with the single-chip microcomputer.

[00017] However, above mentioned references and many other similar references has one or more of the following shortcomings: (a) only used either for fire extinguishing or fire prevention; (b) depends on more than two or three signals/triggers to activate the system; (c) only used for internal fire prevention and/or extinguishing; (d) not monitoring the temperature of the transformer; (g) electrical breaking takes longer time to react/trips than the requirement; (h) complex system structure; (i) Use of water sprinklers for external fire extinguishing which may not be advisable for electric transformer system and further the transformer may be flooded with the water; (j) relay based control circuits are used in the control panel; and (k) not having any device or medium to communicate with the caretaker or the concerned person in case of any fault in the transformer.

[00018] The present application addresses the above mentioned concerns and short comings with regard to providing novel, updated and use of the latest technology providing a method and system for detecting, preventing and/or protecting explosion of an electric transformer.

[00019] SUMMARY OF THE INVENTION

[00020] In the view of the foregoing disadvantages inherent in the known types of methods and systems for fire prevention and/or fire extinguishing in the electric transformer now present in the prior art, the present invention provides asystem for detecting, preventing and/or protecting explosion of an electric transformer. As such, the general purpose of the present invention, which will be described subsequently in greater detail, is to provide a new and improved system for detecting, preventing and/or protecting explosion of an electric transformer which has all the advantages of the prior art and none of the disadvantages.

[00021] An object of the present invention is to provide a system for detecting, preventing and/or protecting explosion of an electric transformer equipped with an oil conservator tank filled with combustible coolant fluid, said system comprising: (i) an oil conservator tank for supplying combustible coolant fluid; (ii) a conservator isolation valve; (iii) a gas relay or buchholz relay for sensing the excessive oil serge in the transformer; (iv) at least one fire detector for detecting an external fire in the transformer; (v) a foam spray system for extinguishing the external fire; wherein the foam spray system further comprises a foam spray main pipe, a foam spray branch pipe and a foam spray nozzle; (vi) a control panel for controlling said system; (vii) a pressure relief valve; (viii) at least one fire protection box, wherein the fire protection box is for monitoring and controlling said foam spray system in case of external fire; and (ix) a nitrogen gas injection system, wherein said nitrogen injection system is for preventing said system foran internal fire/explosion in the electric transformer by draining of the combustible coolant fluid through the oil drain line to the oil drain pit and simultaneously injecting an inert gas or gases from the bottom of the electrical transformer chamber through a nitrogen release pipe.

[00022] It is another object of the present invention to provide the system for detecting, preventing and/or protecting explosion of an electric transformer equipped with an oil conservator tank filled with combustible coolant fluid, wherein the control panel is based on the relay, programmable logic controller (PLC) and/or microprocessor.

[00023] Yet another object of the present invention is to provide the system for detecting, preventing and/or protecting explosion of an electric transformer equipped with an oil conservator tank filled with combustible coolant fluid, wherein the fire protection box connects said foam spray system with said control panel.

[00024] Yet another object of the present invention is to provide the system for detecting, preventing and/or protecting explosion of an electric transformer equipped with an oil conservator tank filled with combustible coolant fluid, wherein the fire detector may comprise fusible type heat detector, probe type bimetal auto reset heat detector, Quartzoid bulb type heat detector, flame detector, UV based fire detector, IR based fire detector, Linear Heat sensing cable detector, Fire De Tec Tube.

[00025] Yet another object of the present invention is to provide the system for detecting, preventing and/or protecting explosion of an electric transformer equipped with an oil conservator tank filled with combustible coolant fluid, wherein the control panel further comprises auto dialer system for sending an alert text and/or audio messages to the preregistered contact numbers.

[00026] Yet another object of the present invention is to provide the system for detecting, preventing and/or protecting explosion of an electric transformer equipped with an oil conservator tank filled with combustible coolant fluid, wherein the inert gas or gases used may be nitrogen, argon, and mixture thereof.

[00027] Yet another object of the present invention is to provide the system for detecting, preventing and/or protecting explosion of an electric transformer equipped with an oil conservator tank filled with combustible coolant fluid, wherein the gas injection system further comprises a system for purging gas or gases automatically and/or manually from the gas cylinders to the electric transformer via hose pipe, gas manifold, gas control valve, gas release valve, gas inlet valve and gas injection pipe. [00028] Yet another object of the present invention is to provide the system for detecting, preventing and/or protecting explosion of an electric transformer equipped with an oil conservator tank filled with combustible coolant fluid, wherein the gas injection system further comprises an oil drain valve and an oil drain pipe for bringing oil from the electric transformer to the oil pit, wherein the oil drain valve is attached and operated by ball valve rod which is further interlocked with the gas purging inlet valve.

[00029] Yet another object of the present invention is to provide the system for detecting, preventing and/or protecting explosion of an electric transformer equipped with an oil conservator tank filled with combustible coolant fluid, the gas injection system may also work manually by releasing gas or gases and/or draining oil.

[00030] In this respect, before explaining at least one embodiment of the invention in detail, it is to be understood that the invention is not limited in its application to the details of construction and to the arrangements of the components set forth in the following description or illustrated in the drawings. The invention is capable of other embodiments and of being practiced and carried out in various ways. Also, it is to be understood that the phraseology and terminology employed herein are for the purpose of description and should not be regarded as limiting.

[00031] These together with other objects of the invention, along with the various features of novelty which characterize the invention, are pointed out with particularity in the disclosure. For a better understanding of the invention, its operating advantages and the specific objects attained by its uses, reference should be had to the accompanying drawings and descriptive matter in which there are illustrated preferred embodiments of the invention.

[00032] BRIEF DESCRIPTION OF THE DRAWINGS

[00033] The invention will be better understood and objects other than those set forth above will become apparent when consideration is given to the following detailed description thereof. Such description makes reference to the annexed drawings wherein: [00034] Fig.l depicting view of one of the embodiments, a system for detecting, preventing and/or protecting explosion of an electric transformer equipped with an oil conservator tank filled with combustible coolant fluid, of the present invention.

[00035] Fig.2 depicting a view of one of the embodiments, a gas injection system, of the present invention.

[00036] Fig. 3 illustrates an example by a flow chart of a method for operating a gas injection system semi-automatic by pushing button in case of internal explosion or fire in the system of the present invention.

[00037] Fig. 4 illustrates an example by a flow chart of a method for operating simultaneously a gas injection system and a foam spray system semi-automatic by pushing button in case of internal and/or external explosion and/or fire in the system of the present invention.

[00038] Fig. 5 illustrates an example by a flow chart of a method for operating simultaneously a gas injection system and a foam spray system by mechanical lever in case of internal and/or external explosion and/or fire in the system of the present invention.

[00039] Fig. 6 illustrates an example by a flow chart of a method for automatic preventing explosion in the system of the present invention.

[00040] Fig. 7 illustrates an example by a flow chart of a method for automatic preventing explosion with external fire extinguishing in the system of the present invention.

[00041] DETAILED DESCRIPTION OF THE INVENTION [00042] In the following detailed description, reference is made to the accompanying drawings which form a part hereof, and in which is shown by way of illustration specific embodiments in which the invention may be practiced. These embodiments are described in sufficient detail to enable those skilled in the art to practice the invention, and it is to be understood that the embodiments may be combined, or that other embodiments may be utilized and that structural and logical changes may be made without departing from the spirit and scope of the present invention. The following detailed description is, therefore, not to be taken in a limiting sense, and the scope of the present invention is defined by the appended claims and their equivalents.

[00043] The present invention is described in brief with reference to the accompanying drawings. Now, refer in more detail to the exemplary drawings for the purposes of illustrating non-limiting embodiments of the present invention.

[00044] As used herein, the term "comprising" and its derivatives including "comprises" and "comprise" include each of the stated integer or elements but does not exclude the inclusion of one or more further or integers or elements.

[00045] As used herein, the singular forms "a", "an", and "the" include plural referents unless the context clearly dictates otherwise .For example, reference to" a device "encompasses a single device as well as two or more devices, and the like.

[00046] As used herein, the terms "for example", "like", "such as", or "including" are meant to introduce examples that further clarify more general subject matter. Unless otherwise specified, here examples are provided only as an aid for understanding the applications illustrated in the present disclosure, and are not meant to be limiting in any fashion.

[00047] Exemplary embodiments will now be described more fully hereinafter with reference to the accompanying drawings, in which exemplary embodiments are shown. These exemplary embodiments are provided only for illustrative purposes and so that this disclosure will be thorough and complete and will fully convey the scope of the invention to those of ordinary skill in the art. The invention disclosed may, however, be embodied in many different forms and should not be construed as limited to the embodiments set forth herein.

[00048] Various modifications will be readily apparent to persons skilled in the art. The general principles defined herein may be applied to other embodiments and applications without departing from the spirit and scope of the invention. Moreover, all statements herein reciting embodiments of the invention, as well as specific examples thereof, are intended to encompass both structural and functional equivalents thereof. Additionally, it is intended that such equivalents include both currently known equivalents as well as equivalents developed in the future (i.e., any elements developed that perform the same function, regardless of structure). Also, the terminology and phraseology used is for the purpose of describing exemplary embodiments and should not be considered limiting. Thus, the present invention is to be accorded the widest scope encompassing numerous alternatives, modifications and equivalents consistent with the principles and features disclosed. For purpose of clarity, details relating to technical material that is known in the technical fields related to the invention have not been described in detail so as not to unnecessarily obscure the present invention.

[00049] Thus, for example, it will be appreciated by those of ordinary skill in the art that the diagrams, schematics, illustrations, and the like represent conceptual views or processes illustrating systems and methods embodying this invention. Those of ordinary skill in the art further understand that the exemplary methods, and/or operating systems described herein are for illustrative purposes and, thus, are not intended to be limited to any particular named element.

[00050] Each of the appended claims defines a separate invention, which for infringement purposes is recognized as including equivalents to the various elements or limitations specified in the claims. Depending on the context, all references below to the "invention" may in some cases refer to certain specific embodiments only. In other cases it will be recognized that references to the "invention" will refer to subject matter recited in one or more, but not necessarily all, of the claims.

[00051] All methods described herein can be performed in any suitable order unless otherwise indicated herein or otherwise clearly contradicted by context. The use of any and all examples, or exemplary language (e.g., "such as") provided with respect to certain embodiments herein is intended merely to better illuminate the invention and does not pose a limitation on the scope of the invention otherwise claimed. No language in the specification should be construed as indicating any non-claimed element essential to the practice of the invention.

[00052] Various terms as used herein are shown below. To the extent a term used in a claim is not defined below, it should be given the broadest definition and persons in the pertinent art have given that term as reflected in printed publications and issued patents at the time of filing.

[00053] Groupings of alternative elements or embodiments of the invention disclosed herein are not to be construed as limitations. Each group member can be referred to and claimed individually or in any combination with other members of the group or other elements found herein. One or more members of a group can be included in, or deleted from, a group for reasons of convenience and/or patentability. When any such inclusion or deletion occurs, the specification is herein deemed to contain the group as modified thus fulfilling the written description of all groups used in the appended claims.

[00054] During a transformer short-circuit, the electrical arc vaporizes oil and creates a dynamic Pressure peak which travels at the speed of 1,200 meters per second (4,000 feet per second). This phenomenon occurs within a few milliseconds. Because of reflections in the tank the pressure peak will generate pressure waves. The integration of all of the wave pressure peaks creates static pressure. Then, the pressure becomes equal throughout the entire transformer tank within 50 to 100 milliseconds after the electrical arc, and causes the transformer tank to rupture. In general principle for fire extinguishing in the electric transformer, on receipt of high pressure and flame signal from the sensors the system opens a drain valve on the top to allow mitigation of expanded oil. Simultaneously gas or gas mixture is injected from the bottom at a predetermined flow rate to remove the explosive gases and cool transformer oil thereby bringing the temperature of oil below ignition point. Many different types of methods and systems are proposed in the prior art, which are explained somewhat in detail in the background of the invention section above. As such, the general purpose of the present invention, which will be described subsequently in greater detail, is to provide a new and improved system for detecting, preventing and/or protecting explosion of an electric transformer which has all the advantages of the prior art and none of the disadvantages.

[00055] Fig.l depicting view of one of the embodiments, a system for detecting, preventing and/or protecting explosion of an electric transformer equipped with an oil conservator tank filled with combustible coolant fluid, of the present invention.

[00056] In an exemplary embodiment, as shown in Fig. 1, a system 100a for detecting, preventing and/or protecting explosion of an electric transformer 100b equipped with an oil conservator tank 102 filled with combustible coolant fluid is disclosed. The system 100a comprises an oil conservator tank 102 for supplying combustible coolant fluid to the transformer; a conservator isolation valve 104; a gas relay or buchholz relay 105 for sensing the excessive oil serge in the transformer 100b; at least one fire detectorl06 for detecting an external fire in the transformerlOOb; a foam spray system; a control panel 116 for controlling said systemlOOa; a pressure relief valve 117; and fire protection boxes(112 and 113).

[00057] One the fire protection box 112 is for monitoring and controlling said foam spray system in case of external fire; and a gas injection system 113 which also works as a one kind of fire protection box. The gas injection system 113 is for preventing the system 100a in case of an internal fire/explosion in the electric transformer by draining the combustible coolant fluid through the oil drain line to the oil drain pit and simultaneously injecting an inert gas or gases from the bottom of the electrical transformer chamber through a nitrogen release pipe. The detailed processes of fire prevention and/or fire extinguishing in case of an internal explosion and/or fire in the transformer are explained in below exemplary embodiments.

[00058] In the transformer, there is also a possibility of external fire break up at any of the location within the transformer area. The system for fire extinguishing is also designed for extinguishing the external fire. The system comprises the foam spray system and further the foam spray system includes a foam spray main pipe 111, a foam spray branch pipe 109 and a foam spray nozzle 107. The foam spray system is connected with the fire protection box 112, which is also connected with the control panel and receives the commands from the control panel 116. The detailed processes of fire extinguishing in case of an external fire is explained in one of the exemplary embodiments.

[00059] The fire detector(s) 106 in the system is used for detecting/sensing flame(s); temperature rising, sparking, smokes, or any other faults. Many different type of the fire detectors can be adopted. For example, the system may include any one or more of the fire detectors selected from the list of fusible type heat detector, probe type bimetal auto reset heat detector, Quartzoid bulb type heat detector, flame detector, UV based fire detector, IR based fire detector, Linear Heat sensing cable detector, and Fire De Tec Tube. Each detector has specific purpose to use.

[00060] The control panel 116 is mainly communicating and controlling all the elements/parts of the system. The elements can be mechanical parts, hardware and/or software. The control panel in the earlier systems reported in the prior art used to work based only on relay type of control circuits. The system of the present invention can be based on programmable logic controller (PLC) and/or microprocessor. The control panel 116 may collect the data and provide the necessary commands to the system. The control panel 116 is connected with the terminal box 110, as the location of the control panel is kept little far from the actual location of the transformer 100b. The control panel 116 further comprises an auto dialer system. The auto dialer system has pre-registered contact mobile and/or landline phone numbers. The auto dialer system has registered local fire department, local electricity office and police department contact numbers as well. The control panel 116 also has facility of storing all the data received from the various sources. The auto dialer system is controlled by the microprocessor and other parts. The control panel also records no. of faults in a log sheet and the auto dialer system will send an alert prerecorded text and/or audio message to any default contact numbers automatically. The control panel also receives signals/inputs from the he wire (control cable) which is used to detect/ any input signal/alert/alarm from the protective device of the transformer, if there is any faulty condition or unhealthy stage of the wire, this will also be detected in our system and will give an audio visual alarm.

[00061] Fig.2 depicting a view of one of the embodiment, a gas injection system, of the present invention. [00062] In an exemplary embodiment of the present invention, Fig. 2 depicts a view of a nitrogen gas injection system. The nitrogen gas injection system 113 in Fig. 1 (which is same as 200 in Fig. 2) is for preventing the system 100a for an internal fire/explosion in the electric transformer by draining of the combustible coolant fluid (i.e., oil) through the oil drain line to the oil drain pit and simultaneously injecting an inert gas or gases from the bottom of the electrical transformer chamber through a nitrogen release pipe. The nitrogen gas injection system 200 comprises a system for purging gas or gases automatically and/or manually from the nitrogen gas cylinders 212 to the electric transformer via hose pipe 214, nitrogen gas manifold 216, nitrogen gas control valve 206, nitrogen gas release valve 204, nitrogen gas inlet valve 203 and nitrogen gas injection pipe 202. The nitrogen gas injection system 200 also comprises an oil drain valve 205 and an oil drain pipe 201 for bringing oil from the electric transformer to the oil pit, wherein the oil drain valve 201 is connected and operated by ball valve rod 208 which is further interlocked with the gas purging inlet valve. There is a sight glass 209 which is placed in the oil drain pipe 201 just after the oil drain valve 205. Further, the hammer 213 is also attached with the oil drain valve 205. The nitrogen gas injection system will work automatically in case of an internal explosion and/or fire; however there is also an arrangement made in the system to operate manually. The nitrogen gas injection system 200 work manually by releasing gas or gases and/or draining oil. The nitrogen gas injection system 200 includes two mechanical levers for manual oil draining 211 and nitrogen gas release 215. The system work in a similar fashion when mixture of gases is supposed to be used for extinguishing fire and/or to prevent explosion. In this case, two or more than two cylinders 212 can be attached in the gas injection system. [00063] In an exemplary embodiment of the present invention, a method for operating a gas injection system semi-automatic by pushing button in case of internal explosion or fire in the system is depicted by flow chart representation in Fig. 3. In case someone observes any critical situation of any fault of the transformer which can be cause of any explosion/Fire he may follow the below steps to operate the system by Pushing a Button provided at the Control Panel:

a) First of all check the Control Panel for a Signal of Transformer tripping off is "ON" to ensure that Transformer has already been trip off or arrange to get the Transformer Tripped off communicating with the Control Room.

b) After that select the "Auto/OFF/Manual" Selector Switch and put on the same at "Manual Position"

c) Also select the "Nitrogen Injection / Nitrogen Injection + Foam Spray" Selector Switch and put it at "Nitrogen Injection Position".

d) Press the Push Button to Activate the System.

e) Under this operation, the Oil draining, shutting of the transformer conservator tank isolation valve, Auto dialer activation and Nitrogen Injection will take place.

[00064] In an exemplary embodiment of the present invention, a method for operating simultaneously a gas injection system and a foam spray system semi-automatic by pushing button in case of internal and/or external explosion and/or fire in the system is depicted by flow chart representation in Fig. 4. In case someone observes any critical situation of any fault of the transformer which can be cause of any explosion/Fire he may follow the below steps to operate the system by Pushing a Button provided at the Control Panel:

a) First of all check the Control Panel for a Signal of Transformer tripping off is "ON" to ensure that Transformer has already been trip off. OR arrange to get the Transformer Tripped off communicating with the Control Room.

b) After that select the "Auto/OFF/Manual" Selector Switch and put on the same at "Manual Position"

c) Also select the "Nitrogen Injection / Nitrogen Injection + Foam Spray" Selector Switch and put it at "Nitrogen Injection + Foam Spray Position".

d) Press the Push Button to Activate the System. e) Under this operation, The Oil draining, Shutting of the transformer conservator tank isolation valve, Auto dialer activation and Nitrogen Injection + Foam Spray will take place.

[00065] In an exemplary embodiment of the present invention, a process for operating simultaneously a gas injection system and a foam spray system manually by using mechanical lever in case of internal and/or external explosion and/or fire in the system is depicted by flow chart in Fig. 5. In case someone observes any critical situation of any fault of the transformer which can be cause of any explosion/Fire he may follow the below steps to operate the system by triggering the Mechanical Lever provided inside the Fire Extinguishing Cubical (FEC) Installed near the Transformer itself:

(a) First of all check the Control Panel for a Signal of Transformer tripping off is "ON" to ensure that Transformer has already been trip off. OR arrange to get the Transformer Tripped off communicating with the Control Room.

(b) First of all trigger the "Mechanical Lever" to activate the Oil Darin Valve and get ensured for the indication received from the Transformer conservator Isolation Valve Shutting off after few seconds.

(c) Now trigger the "Mechanical Lever" to activate the Nitrogen Injection System.

(d) Now trigger the "Mechanical Lever" to activate the Foam Spray System if required.

[00066] In an exemplary embodiment of the present invention, a method for automatic explosion prevention is depicted by flow chart representation in Fig. 6. On receipt of input signal from Gas relay for indicating the trouble generated inside the Transformer by any fault condition it produce an alert in our control Panel by Audio Visual alarm only where as when the same trouble is converted into an increase of pressure inside the transformer it resulted a second signal received from pressure relief valve fitted on the Transformer body. On receipt of these both signals the system is activated by opening the Oil Drain Valve (Subject to the Circuit Breaker of the Transformer also got tripped simultaneously by any one or both signal out of these two, the signal of this tripping is also essential to receive at control panel for activation of system, because the said system is inter locked with the Circuit Breaker Tripping of the Transformer in every situation and on receipt of the tripping signal the auto Dialer also activated) As soon as the Oil from the Transformer body starts draining which prevent the explosion of the Transformer, Oil stored in Transformer Conservative Tank also starts to flow into the Transformer body to make up the oil level inside the Transformer, this flow of oil is required to stop immediately, therefore with the sensation of this sudden increase in flow of Oil from Transformer Conservative Tank to the Transformer Body activate our Transformer Conservative Isolation Valve to shut off And a signal of closing for this valve also receive at control panel accordingly. [00067] On the other hand just after delay of few seconds from the opening of the Oil Drain valve (Which is also mechanically Inter locked with the Nitrogen Gas Inlet Valve) the Nitrogen Injection is also activated to flow inside the transformer for its cooling.

[00068] In an exemplary embodiment of the present invention, a method for automatic explosion prevention and fire extinguishing in the system is depicted by flow chart representation in Fig. 7. This situation suggests that in case of occurrence of only external fire the system works simultaneously to extinguish the external fire as well as turning on the internal fire explosion prevention system. On receipt of input signal from any one either from Gas relay for indicating the trouble generated inside the Transformer by any fault condition it produce an alert in our control Panel by Audio Visual alarm only where as when the same trouble is converted into an increase of pressure inside the transformer it resulted a second signal received from pressure relief valve fitted on the Transformer body. On receipt of these both signals the system is activated by opening the Oil Drain Valve (Subject to the Circuit Breaker of the Transformer also got tripped simultaneously by any one or both signal out of these two, the signal of this tripping is also essential to receive at control panel for activation of system, because the said system is inter locked with the Circuit Breaker Tripping of the Transformer in every situation and on receipt of the tripping signal the auto Dialer also activated) As soon as the Oil from the Transformer body starts draining which prevent the explosion of the Transformer, Oil stored in Transformer Conservative Tank also starts to flow into the Transformer body to make up the oil level inside the Transformer, this flow of oil is required to stop immediately, therefore with the sensation of this sudden increase in flow of Oil from Transformer Conservative Tank to the Transformer Body activate our Transformer Conservative Isolation Valve to shutting off And a signal of closing for this valve also receive at control panel accordingly.

[00069] On the other hand just after delay of few seconds from the opening of the Oil Drain valve (Which is also mechanically Inter locked with the Nitrogen Gas Inlet Valve) the Nitrogen Injection is also activated to flow inside the transformer for its cooling.

[00070] In addition of above function of the system in case a signal is also received from Fire Detector fitted on the transformer body surrounding the bushing areas which is an indication of External Fire or Oil Spillage over the transformer body, the Foam Spray System is also activated to spray the foam over the transformer body. This is an extra external protection of the transformer along the Oil Draining and Nitrogen Injection inside the transformer body. [00071] It is to be understood that the above description is intended to be illustrative, and not restrictive. For example, the above-discussed embodiments may be used in combination with each other. Many other embodiments will be apparent to those of skilled in the art upon reviewing the above description.

[00072] The benefits and advantages which may be provided by the present invention have been described above with regard to specific embodiments. These benefits and advantages, and any elements or limitations that may cause them to occur or to become more pronounced are not to be construed as critical, required, or essential features of any or all of the embodiments.

[00073] While the present invention has been described with reference to particular embodiments, it should be understood that the embodiments are illustrative and that the scope of the invention is not limited to these embodiments. Many variations, modifications, additions and improvements to the embodiments described above are possible. It is contemplated that these variations, modifications, additions and improvements fall within the scope of the invention.