MNB Automatic Load Sharing OfTransformers

Post on 17-Jul-2016

60 views 11 download

description

hjhjhjk

transcript

• To design & fabrication of a hardware which will monitor the performance of the load sharing process by taking power consumed by the load into consideration.

• To protect the power transformer from over load power.

o The transformer cannot supply load more than its rated capacity.

oSo, by introducing another transformer, reduces the load on the transformers.

o load sharing of transformer is possible with this scheme so life of the transformer is increased.

oHere 2 transformers are connected through a relay.

• Load is directly connected to secondary of the main transformer as well as slave transformer.

• A sensor circuit is used to log data from the main transformer .

• If sensor found the overvoltage condition, immediately the slave transformer will be connected in parallel to the main transformer & the load is shared.

Transformers –

o Transformer is a static device which consist of two or more stationary electric circuit interlinked by a common magnetic circuit for the purpose of transferring electrical energy between them.

o The transfer of energy from one circuit to another takes place without change in frequency. o Here we are using 2 transformer- main & slave transformers. o Rating of both the transformers- 230/12v & 3A.

o Both transformers of same rating are connected in parallel through a relay.

• Comparator-

LM324 is used as a comparator.

It is used to compare load with the standard load capacity of a transformer.

When the load capacity exceeds the capacity of load it give signal to relay to switch on the slave transformer in parallel to the main transformer.

Relay-

o A relay is an electrically operated switch.

o Relays allow one circuit to switch a second circuit which can be completely separate from the first.

o In this we are using electromagnetic relay consists of a multi-turn coil, wound on an iron core, to form electromagnet.  When the coil is energised, by passing current through it, the core becomes temporarily magnetised. The magnetised core attracts the iron armature.

Load Bank-

o Assume that we are using set bulbs as a load, connected at the secondary of a transformers.

Transformer rating is= 12VX 3A = 36 VA or

watt Load capacity(rating) = >36watt ~ 3- 10watt

bulbs & 1- 2 watt

1. Automated load sharing of transformers.

2. Prevent transformer and system from destroying or malfunctioning.

5. Low cost and reliable system

3. Over heating of transformer secondary is prevented by this.

4. Highly sensitive.

3. Protection from overloading of transformers.

2. Process Industry.

1. Power generation & distribution system.

4. Uninterrupted power supply.