FORM 2
The Patents Act 1970
(39 of 1970)
&
The Patent Rules 2003 PROVISIONAL SPECIFICATION
(See Section 10 and rule 13)


TITLE OF THE INVENTION:
HIGH CURRENT PATH CIRCUIT FOR POWER SUPPLY SYSTEM
APPLICANT:
LARSEN & TOUBRO LIMITED
L&T House, Ballard Estate, P.O. Box No. 278,
Mumbai- 400 001, Maharashtra. INDIA.
PREAMBLE OF THE DESCRIPTION:
THE FOLLOWING SPECIFICATION PARTICULARLY DESCRIBES THE INVENTION AND THE MANNER IN WHICH IT IS TO BE PERFORMED

A) TECHNICAL FIELD
[0001] The present invention generally relates to power supply distribution systems and particularly to three phase power supply systems. The present invention more particularly relates to three-phase four-wire systems. The present invention relates to the Physical arrangement of a current path to carry higher ratings of current in three-phase four-wire systems where harmonic components are present.
B) BACKGROUND OF THE INVENTION
[0002] In most of the three-phase four-wire systems, where single phase load is connected between the phase conductor and neutral conductor, the neutral conductor serves as the common return for all the single phase load currents. It is a property of three phase power systems that if each of the three hot conductors has a nearly equivalent load, that the neutral current will be nearly zero due to the fact that each phase current is "out of phase" with the other. In other words, the load currents "cancel out" in the neutral wire. But this is not the case with non linear loads like computer loads, fluorescent lighting ballasts, etc. Unfortunately, the harmonic currents created by computers cause the operation of this system to change. Computers generate a substantial amount of 3rd harmonic current. Due to the mathematical phase properties, third harmonic currents add instead of cancel out on the neutral wire.
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[0003] Overloads are caused by the harmonics currents generated by the power supplies within the equipment. Harmonics in an electrical distribution system are caused by the types of loads connected to the system. Modern electronic equipments and control systems draws current in a non-linear fashion, causing harmonic currents to flow throughout the system. The extra currents may result in overloading or failure of system components, line voltage distortion, higher common mode voltage, nuisance tripping of circuit breaker.
[0004] The problem arises in buildings with three-phase four-wire power distribution system. In a typical building, the majority of the power is distributed via single phase 120 volt branch circuits which are connected to the power outlets. If a shared neutral conductor is used for a plurality of single phase branch circuits, a potential for a sever overload condition exists for that conductor.
[0005] The conventional electric power distribution system includes an inexpensive and reliable method and apparatus for monitoring current in a neutral circuit for three-phase four-wire electric power distribution systems. It detects the harmonic currents flowing in the neutral circuit. This requires a separate arrangement in the power system to detect the harmonic currents flowing in the neutral circuit. The currently available systems for carrying higher current have an additional system or device to conduct the higher current.
[0006] None of the currently available power supply distribution system has a simple and easy solution to conduct the higher current using the existing infrastructure.
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[0007] Hence there is a need to provide a physical arrangement to carry higher rating current such as harmonics current easily efficiently and economically without modifying the existing infrastructure in three-phase four-wire system.
C) OBJECTS OF THE INVENTION
[0008] The primary object of the present invention is to provide a physical path to carry higher current than phase current easily, efficiently and economically without increasing the infrastructure.
[0009] Another object of the present invention is to provide a physical path to carry higher harmonic current easily and efficiently.
[0010] Yet another object of the present invention is to provide a physical arrangement to carry higher current easily and efficiently using the existing housing.
[0012] Yet another object of the present invention is to provide a physical arrangement to carry higher ratings of current to prevent the tripping of the switch due to neutral overload.
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[0013] Yet another object of the present invention is to provide a physical arrangement to carry higher ratings of current to provide a neutral overload to prevent the over heating of the neutral conductor.
[0014] These and other objects and advantages of the present invention will become readily apparent from the following detailed description, taken in conjunction with the accompanying drawings.
D) SUMMARY OF THE INVENTION
[0015] The above mentioned shortcomings, disadvantages and problems are addressed herein and which will be understood by reading and studying the following specification.
[0016] The various embodiments of the present invention provide a physical arrangement to carry higher rating current using the existing infrastructure and without increasing the housing in industry such as Information Technology industry. According to one embodiment, a single pole per phase is provided to carry the rated current and two poles are additionally provided in the same switch housing to carry the higher ratings of current than the phase current. The two poles are arranged in parallel to carry the higher ratings of current than the phase current. The two poles may be placed consecutively any where in the switch housing in two consecutive slots to conduct the higher current.
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[0018] Thus the present invention provide two additional poles in the existing switch housing in addition to the single pole provided corresponding to each phase to carry the higher rated current than the phase current to prevent the over heating of the neutral conductor and to avoid the tripping of the switch due neutral over load. The present invention is used in IT industry where higher harmonic components are present in the power supply system. The system provides a physical path for the higher currents using the existing switch housing thereby eliminating the need for any additional housing.
[0019] These and other objects and advantages of the present invention will become readily apparent from the following detailed description taken in conjunction with the accompanying drawings.
E) BRIEF DESCRIPTION OF THE DRAWINGS
[0020] The other objects, features and advantages will occur to those skilled in the art from the following description of the preferred embodiment and the accompanying drawings in which:
[0021] FIGURE. 1 shows a front perspective view of a switch provided with extra poles to carry higher current according to one embodiment of the present invention.
[0022] FIGURE.2 shows a functional block diagram of a circuit for carrying the higher current rating according to one embodiment of the present invention.
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[0023] Although specific features of the present invention are shown in some drawings and not in others. This is done for convenience only as each feature may be combined with any or all of the other features in accordance with the present invention.
F) DETAILED DESCRIPTION OF THE INVENTION
[0024] The various embodiments of the present invention provide a physical arrangement to carry higher rating current using the existing infrastructure and without increasing the housing in industry such as Information Technology industry. According to one embodiment, a single pole per phase is provided to carry the rated current and two poles are additionally provided in the same switch housing to carry the higher ratings of current than the phase current. The two poles are arranged in parallel to carry the higher ratings of current than the phase current.
[0025] The FIG.l shows a front perspective view of a switch provided with extra poles to carry higher current according to one embodiment of the present invention. With respect to FIG.l, three poles are provided corresponding to each phase conductor. Additional two poles are arranged in two consecutive slots in the same switch housing to carry the higher ratings of current than the phase current.
[0026] FIGURE.2 shows a functional block diagram of a circuit for carrying the higher current rating according to one embodiment of the present invention. With respect to
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FIG.2, R, Y, B phases are used to carry the rated current and the neutral pole is used to carry double the rated current. This arrangement may be interchanged for any phase as per the application to carry the higher ratings of the current.
[0027] Thus the present invention provide two additional poles in the existing switch housing in addition to the single pole provided corresponding to each phase to carry the higher rated current than the phase current to prevent the over heating of the neutral conductor and to avoid the tripping of the switch due neutral over load. The present invention is used in IT industry where higher harmonic components are present in the power supply system. The system provides a physical path for the higher currents using the existing switch housing thereby eliminating the need for any additional housing.
G) ADVANTAGES OF THE INVENTION
[0029] The present invention provide two additional poles in the existing switch housing in addition to the single pole provided corresponding to each phase to carry the higher rated current than the phase current to prevent the over heating of the neutral conductor and to avoid the tripping of the switch due neutral over load. The present invention is used in IT industry where higher harmonic components are present in the power supply system. The system provides a physical path for the higher currents using the existing switch housing thereby eliminating the need for any additional housing.
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The detailed scope of the monopoly claimed for the invention shall be ascertained and provided at the time of filing of the Complete Specification.
Dated this 28th of October, 2008
Rakesh Prabhu,
Patent Agent, ALMT Legal,
No.2, Lavelle Road, Bangalore-560 001, INDIA
To,
The Controller of Patents, The Patent office, Mumbai
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