Shri Khalsa Enterprises

Bairia, Muzaffarpur, Bihar

Supply a wide range of technically advanced OLTC Distribution Transformers, which is a on load tap changer. This transformer is used to maintain the constant voltage by changing the voltage level of secondary winding. On-load tap changers may be generally classified as either mechanical, electronically assisted, or fully electronic. If only one tap changer is required, tap points are usually made on the high voltage, or low current, side of the winding to minimize the current handling requirements of the contacts. These transformers are predominantly used in the devices where current is required to be obtained. It obtains the current from the Secondary circuit and measures the Alternating Circuit (A.C) with the help of the conductor. They can function without any issue and transfer the current directly to the necessary circuits. These are manufactured under the expert engineer’s guidance.

The Electrical Transformer, which we present to our clients is comprehensive of high quality and is widely acknowledged in the market due to their affordable pricing. Avilable in all class and voltage rating.

Special Duty Transformers (SDTs) are explained by its name itself, these are made for a specific purpose / application. From designing to manufacturing everything is special and specific.

Few types of SDTs are listed below :

• Dual Ratio Transformers
• Auto Transformers
• Rectifier Transformers
• Reactor Transformers
• Earthing Transformers
•  LT – LT Transformers
• Dual Secondary Transformer for Solar PV Application
• Package Sub Station Transformer with RMU & LVDB

Other Details :

• PVJ Power designs and manufactures custom designed special transformers for industrial and power applications. We offer customized maintenance and service solutions for transformers with state-of-the-art machinery & equipment and testing facilities.
• In PVJ Power each transformer is designed as a new product and customized to comply with specific customer requirements. The PVJ Power engineering team covers the complete design of a transformer, from designing of core and coils to the tank and the supporting structures with proper cooling system and full protection.
• Transformer engineering begins from electromagnetic and thermal design of core and windings. This activity is performed by means of standardized calculation sheets developed by our Design Department over the years. 2D and 3D FEM software tools are used for particular studies, such as: short-circuit impedances of phase-shifted multi-winding transformers, eddy
• current and stray losses calculation due to harmonics, hot-spots calculation and localization on windings and carpentry, mechanical stresses due to short-circuit, insulation assessment.
• Transformer mechanical design is carried out using 3D software tools allowing dimensions optimization, mechanical stress evaluation and taking into account special external conditions (Seismic Zone, Low Noise Level).
• Each transformer is supplied with a set of basic documents describing its features and functionalities, such as fabrication drawings, HV/LV connection drawings, auxiliary circuit / schematic wiring diagrams, cooling system drawings, user’s manual.

Details :

• Induction Furnace has coil constructed from heavy copper tubing. It is designed and tuned to the inverter circuit which applies a medium frequency (generally 500 Hz or 1000 Hz) voltage to the Induction coil. The magnetic field produced by the induction coil induces eddy currents in the charge and heats it. Medium frequency is necessary to enhance the rate of heat generation.
• The inverter circuit requires for its operation a D.C. Voltage which is obtained by converting available three phase A.C. Voltage. Transformers which are used for transforming available three phase A.C. voltage to required voltage for converter circuit of the Induction Furnace are referred to as Induction Furnace Transformers. Thus they are essentially Rectifier/ Converter Duty Transformers.
• Depending on the rating of the rectifier transformers, input voltage is derived from standard three phase AC distribution voltages like 433 V, 3.3 kV, 6.6 kV, 11 kV, 22 kV, 33 kV etc. These become the primary (or line side) voltage of the transformer. Secondary (or cell side) voltage can be between 400 to 1000 V decided by the required D.C. output Voltage.
• These transformers must be designed to resist the high levels of electrical, thermal and mechanical stress to which they are subject during utilisation.
• Other elements that must be taken into consideration when designing transformers for electric-arc furnaces are the high secondary currents required for the fusion process (dozens of kA) and the wide range of secondary voltages, which are normally regulated by an on-load tap changer (OLTC), either directly on the high-voltage winding or via an intermediate booster located within the same tank.
• The furnace transformer thus has special features to handle such high currents as compared to conventional transformers. The electric arc furnace has 3 electrodes connected to the secondary terminals of the furnace transformers. The secondary terminals of the transformers are subject to frequent short circuits during the melting process through the charge and arc. Hence the furnace transformer needs to be specially designed to withstand the frequent short circuits.

ECO-SMART is our range of High Energy Saving Distribution Transformers, which has minimum Electrical Losses among its peers. A Transformer, like any other electrical device has its own electrical losses. Due to the nature of the HT metering, as shown in the diagram above, these electrical losses are charged in your electricity bill by the Discom. To avoid paying un-necessary high bills it is wise to use transformers with lower electricity bills, which offer you the lowest in-class electrical losses. For this we offer you our range of ECO-SMART Technology Energy Efficient Distribution Transformers. Use of ECO-SMART transformers leads you to save on your monthly electricity consumption, which in turn leads to lower electricity bill & also gives a longer life to the transformer. With ECO-SMART Technology the transformer is designed in such a way, so it’s easy to take care of & maintain. Due to the high efficiency of ECO-SMART Transformers, the entire cost of the transformer can be recovered in the shape of electrical savings, within 3-6 years of use. All our customers who have installed an ECO-SMART transformer are today reaping the benefits of saving on their monthly electricity bills due to Energy Efficient ECO-SMART Technology being used in their transformers.