CLIAMS:CLAIMS
We claim:-

1. A system and mechanism for PLC based load sharing of transformer which is capable of sharing loads among several installed sources means according to increased loads it automatically adds new sources of power and in case of decrement in loads sources will automatically cut out wherein the transformers are connected in parallel instead of connecting single larger unit the PLC base is connected at the input side of the load wherein the preferred embodiment mainly comprises of PLC, SMPS, relays, transformers, load.

2. The system claimed in claim 1 is capable of sharing loads among several installed sources means according to increased loads it automatically adds new sources of power and in case of decrement in loads sources will automatically cut out.

3. In one of the preferred embodiments of the invention as claimed in claim 1 where three transformers are connected in parallel instead of connecting single larger unit:
a) the PLC base is connected at the input side of the load;
b) The PLC system is analyzing the load requirement of the system and relays are provided for on / off operation of PLCs;
c) one toggle switch is also provided to connect or disconnect the transformer according to the load;
d) When the load on the system is increases the PLC send signal and no of transformer connected in parallel are increases and if load require less power than any one of the transformer or two of them is disconnected automatically using plc.

4. In one of the preferred embodiments of the device as claimed in claim 1 where three transformers are working as sources:
a) At very first time 1st transformer is under working condition and it will be remain as it is till it continues its supply;
b) If any faults occur and its supply to load is interrupted the second transformer will automatically come in role and the transformer one will be removed;
c) Now take another case consider 1st transformer is in work and if increasing loads becomes more than its rated capacity the 2nd transformer will automatically be added in the circuit and for further loads next sources will be added and so on
d) And vice versa if load is decreased transformer will be removed.

5. The system as claimed in claim 1 is automated by using PLC and it is programmed according to the requirement that will be capable of automatic switching of transformer circuits and will operate them.
,TagSPECI:FORM 2
THE PATENT ACT 1970
(39 OF 1970)
AND
The patent rules, 2003
COMPLETE SPECIFICATION
(See section 10: rule 13)

1. TITLE OF INVENTION
PLC based Load Sharing of Transformer

2 APPLICANTS
Name Nationality Address
Sandip foundations Sandip institute of engineering and management Indian Sandip institute of Engineering & Management, Mahiravani, Trimbak road, Nashik, Maharashtra

3. PREAMBLE TO THE DESCRIPTION

COMPLETE
Following specification particularly describes the invention and the manner in which it is to be performed.

4. DESCRIPTION.

Technical field of invention:

Present invention in general relates to system and mechanism for PLC based load sharing of transformer and in particular to a system which is capable of sharing loads among several installed sources.

Prior art:-

Electrical power distribution and transmission have a number of problems. This is particularly true when three-phase distribution is being performed. As many simple loads are single phase loads, it then becomes necessary to balance the loads in a three phase system so that one particular phase is not overloaded. The overloading can require additional transformer sizing, wire sizing and so on to handle the additional currents, and can be destructive to the various equipment if not properly sized. If properly sized to handle the imbalance, this results in more expensive components and unused capacity in the lightly loaded phases.

So while load balancing is highly desirable, in many cases this is very difficult to perform. For instance, in a distribution system loads are commonly switched on and off, so that while under maximum load conditions a balanced or near balanced condition could be present, under less than full load conditions where certain loads are on and certain loads are off, an imbalance can readily develop. As this imbalance develops, then of course the primary currents are unbalanced and this trickles up through the entire system, causing problems.
Transformer structure for smart load balancing is described in US 20120277926 A1. A load balancing system includes a transformer having a plurality of integrated sensors. A control system that may be embedded within the transformer is in electrical communication with the plurality of sensors. The control system is configured to estimate or determine the state of health of the transformer. The state of health of the transformer is based upon signals generated via the plurality of sensors. A load request that may be received that is compared to the state of health of the transformer to determine if the transformer can support the load request. The control system determines whether or not the transformer can provide electrical power based upon the estimated state of health of the transformer and in response to the load request.

US 20120065804 A1 discloses a system and method for real-time feeder reconfiguration for load balancing in distribution system automation. The load balancing of transformers and feeders can be achieved by load transfer from an overloaded transformer or feeder to an adjacent transformer or feeder which is lightly loaded. An exemplary method can include defining an objective function as a sum of squares of the load deviation of transformers/feeders. The minimization of this objective function determines the optimal operating states (open or closed) of sectionalizing switches. The load balancing operation of transformer and feeder can be carried out by a single operation in which a plurality of switches is reconfigured.

WO 2013079739 A1 describes a system and method for reducing losses in parallel transformer systems in distribution centers. The invention relates to a system and method for reducing losses in parallel transformer systems in distribution centers. The method comprises: measuring the total load capacity SL of the parallel transformers of the distribution center; comparing load value SL with an optimization capacity value obtained as a function of the total transformation capacity (SN) of the parallel transformers; selecting a transformer connection configuration that is determined as a function of the comparison; and changing the selected connection configuration when it does not match the active connection configuration. The invention is suitable for centers in which electric energy usage is very variable (industrial parks, shopping centers, schools, seasonal tourist centers, etc.).

US 7701357 B2 discloses A system, device, and method of detecting an overload condition of a distribution transformer that supplies power to one or more customer premises via a low voltage subnet is provided. In one embodiment, the method comprises determining the power output of the transformer; storing in a memory a threshold power value for the transformer; determining whether the power output exceeds the threshold power value; and, if the output power exceeds the threshold power value, providing a notification. Providing the notification may include wirelessly transmitting the notification and/or transmitting the notification over a medium voltage power line. The low voltage subnet may comprise a low voltage feeder that supplies power to a plurality of low voltage supply lines that extend to the customer premises in which case determining the output power may comprise measuring a voltage of the low voltage feeder and measuring a current traversing the low voltage feeder. The method may also comprise storing in the memory a plurality of threshold power values associated with a plurality of transformers, such as different models of transformers; receiving data of the power output of a multitude of transformers; and determining whether the power output of each of the multitude of transformers exceeds the threshold value associated with the transformer, which steps may be performed at a central computer system such as a power line server.

US 6906630 B2 describes transformer management system and method. A transformer management system and method involves using sensors to sense physical quantities associated with the operation of a transformer. Processing circuitry uses the sensed physical quantities to calculate values from mathematical models for representing behavior of the transformer. These calculated values are compared to threshold values and an output is generated based on the result of the comparison.

US 20060251147 A1 discloses Transformer temperature monitoring and control system. According to one embodiment an apparatus to monitor the temperature of a transformer is disclosed. The apparatus includes a bundled fiber optic cable having a temperature sensing probe on one end. The probe is embedded in windings of a transformer. An optical converter transmits light to the probe and receives light from the probe, and converts the light received to an electrical signal. The light received back from the probe is controlled by temperature of the probe. A controller converts the electrical signal into a temperature. Other embodiments are disclosed herein.

Another US 7072293 B2 discloses Load sharing/ trunking in a communication device. A method and apparatus is described which pertains to load sharing/trunking in a communication device used in unicast and/or multicasting interchange of information. A plurality of available ports in the interface cards of the device is identified. More than one port is selected to be configured as a Multi-Link Trunk (MLT) even through the ports may be located on different interface cards.

Therefore there is an urgent requirement of the improved load sharing system and apparatus to prevent the drawbacks of the conventional system. Hence the present invention implements a system and mechanism for PLC based load sharing of transformer.

Object:

1. Primary object of the present invention is to provide system and mechanism for PLC based load sharing of transformer.

2. Another object of the present invention is to provide a system which is capable of sharing loads among several installed sources.

3. Yet another object of the present invention is to increase the reliability of the system with parallel operation than to have single larger unit.

4. Yet another object of the present invention is to provide lower cost associated with maintaining the spares less when two transformers are connected in parallel than that of a single large transformer.

5. Yet another object of the present invention is to provide the PLC based system comprises more than reasonable its charge of installation.
6. Yet another object of the present invention is to provide system which is extremely less issue to human error than a system of manual.

7. Yet another object of the present invention is to provide PLC based system which is flexible while the program can be updated quite easily to integrate adaptations.

Other objects, features and advantages will become apparent from detail description and appended claims to those skilled in art.

STATEMENT:

Accordingly following invention provides a system and mechanism for PLC based load sharing of transformer. For supplying a load in excess of the rating of an existing transformer, two or more transformers may be connected in parallel with the existing transformer. The transformers are connected in parallel when load on one of the transformers is more than its capacity. The reliability is increased with parallel operation than to have single larger unit. A system is designed which is capable of sharing loads among several installed sources. It means according to increased loads it automatically adds new sources of power and in case of decrement in loads sources will automatically cut out. The three transformers are connected in parallel instead of connecting single larger unit the PLC base is connected at the input side of the load. The PLC system is analyzing the load requirement of the system as shown in fig. relays are provided for on / off operation of PLCs and one toggle switch is also provided to connect or disconnect the transformer according to the load. When the load on the system is increases the PLC send signal and no of transformer connected in parallel are increases and if load require less power than any one of the transformer or two of them is disconnected automatically using PLC. The preferred embodiment mainly comprises of PLC, SMPS, relays, transformers, load, etc.

BRIEF DESCRIPTION OF DRAWING:

This invention is described by way of example with reference to the following drawing where,

Figure 1 of sheet 1 shows PLC based load sharing system of transformer.
Where,
1 denotes 220V ac supply
2 denotes TF1 220/12V AC
3 denotes TF2 220/12V AC
4 denotes TF3 220/12V AC
5 denotes Toggle Switch
6 denotes Load 1
7 denotes Load 2
8 denotes Load 3
9 & 10 denotes Relay 8 pin/12V DC
11 denotes SMPS
12 denotes PLC (Allen Bradley Micrologix 1000).

In order that the manner in which the above-cited and other advantages and objects of the invention are obtained, a more particular description of the invention briefly described above will be referred, which are illustrated in the appended drawing. Understanding that these drawing depict only typical embodiment of the invention and therefore not to be considered limiting on its scope, the invention will be described with additional specificity and details through the use of the accompanying drawing.

Detailed description:

PLCs are used in many industries and machines. Unlike general-purpose computers, the PLC is designed for multiple inputs and output arrangements, extended temperature ranges, immunity to electrical noise, and resistance to vibration and impact. Programs to control machine operation are typically stored in battery-backed-up or nonvolatile memory. A PLC is an example of a hard real time system since output results must be produced in response to input conditions within a limited time, otherwise unintended operation will result.

For supplying a load in excess of the rating of an existing transformer, two or more transformers may be connected in parallel with the existing transformer. The transformers are connected in parallel when load on one of the transformers is more than its capacity. The reliability is increased with parallel operation than to have single larger unit. The cost associated with maintaining the spares is less when two transformers are connected in parallel. It is usually economical to install another transformer in parallel instead of replacing the existing transformer by a single larger unit. The cost of a spare unit in the case of two parallel transformers (of equal rating) is also lower than that of a single large transformer. In addition, it is preferable to have a parallel transformer for the reason of reliability. With this at least half the load can be supplied with one transformer out of service. In this project we are designing a system which is capable of sharing loads among several installed sources. It means according to increased loads it automatically adds new sources of power and in case of decrement in loads sources will automatically cut out.
The PLC based load sharing system is as shown in fig. 1.

Working of the invention:-

The three transformers are connected in parallel instead of connecting single larger unit the PLC base is connected at the input side of the load. The PLC system is analyzing the load requirement of the system as shown in fig. relays are provided for on / off operation of PLCs and one toggle switch is also provided to connect or disconnect the transformer according to the load. When the load on the system is increases the PLC send signal and no of transformer connected in parallel are increases and if load require less power than any one of the transformer or two of them is disconnected automatically using plc. This type of operation is carried very easily by above system.

There are three transformers working as sources in this project. At very first time 1st transformer is under working condition and it will be remain as it is till it continues its supply. If any faults occur and its supply to load is interrupted the second transformer will automatically come in role and the transformer one will be removed. Now take another case consider 1st transformer is in work and if increasing loads becomes more than its rated capacity the 2nd transformer will automatically be added in the circuit and for further loads next sources will be added and so on. And vice versa if load is decreased transformer will be removed. All this system is automated by using PLC. We will program the PLC according to our requirement that will be capable of automatic switching of transformer circuits and will operate them.

Additional advantages and modification will readily occur to those skilled in art. Therefore, the invention in its broader aspect is not limited to specific details and representative embodiments shown and described herein. Accordingly various modifications may be made without departing from the spirit or scope of the general invention concept as defined by the appended claims and their equivalents.

Adv. Swapnil Gawande (IN/PA/1587)

CLAIMS
We claim:-

1. A system and mechanism for PLC based load sharing of transformer which is capable of sharing loads among several installed sources means according to increased loads it automatically adds new sources of power and in case of decrement in loads sources will automatically cut out wherein the transformers are connected in parallel instead of connecting single larger unit the PLC base is connected at the input side of the load wherein the preferred embodiment mainly comprises of PLC, SMPS, relays, transformers, load.

2. The system claimed in claim 1 is capable of sharing loads among several installed sources means according to increased loads it automatically adds new sources of power and in case of decrement in loads sources will automatically cut out.

3. In one of the preferred embodiments of the invention as claimed in claim 1 where three transformers are connected in parallel instead of connecting single larger unit:
a) the PLC base is connected at the input side of the load;
b) The PLC system is analyzing the load requirement of the system and relays are provided for on / off operation of PLCs;
c) one toggle switch is also provided to connect or disconnect the transformer according to the load;
d) When the load on the system is increases the PLC send signal and no of transformer connected in parallel are increases and if load require less power than any one of the transformer or two of them is disconnected automatically using plc.

4. In one of the preferred embodiments of the device as claimed in claim 1 where three transformers are working as sources:
a) At very first time 1st transformer is under working condition and it will be remain as it is till it continues its supply;
b) If any faults occur and its supply to load is interrupted the second transformer will automatically come in role and the transformer one will be removed;
c) Now take another case consider 1st transformer is in work and if increasing loads becomes more than its rated capacity the 2nd transformer will automatically be added in the circuit and for further loads next sources will be added and so on
d) And vice versa if load is decreased transformer will be removed.

5. The system as claimed in claim 1 is automated by using PLC and it is programmed according to the requirement that will be capable of automatic switching of transformer circuits and will operate them.

Adv. Swapnil Gawande (IN/PA/1587)

Sandip foundations Sandip institute of engineering and management
Sheet 1/1

Figure 1

Adv. Swapnil Gawande (IN/PA/1587)

ABSTRACT

A Programmable Logic Controller, PLC or Programmable Controller is a digital computer used for automation of electromechanical processes, such as control of machinery on factory assembly lines, amusement rides, or light fixtures. PLCs are used in many industries and machines. Unlike general-purpose computers, the PLC is designed for multiple inputs and output arrangements, extended temperature ranges, immunity to electrical noise, and resistance to vibration and impact. For supplying a load in excess of the rating of an existing transformer, two or more transformers may be connected in parallel with the existing transformer. The transformers are connected in parallel when load on one of the transformers is more than its capacity. The reliability is increased with parallel operation than to have single larger unit. In this project we are designing a system which is capable of sharing loads among several installed sources. It means according to increased loads it automatically adds new sources of power and in case of decrement in loads sources will automatically cut out. Following invention is described in detail with the help of Figure 1 of sheet 1 showing PLC based load sharing system.