Vritti Associates

Mahim, Mumbai, Maharashtra

Toroidal Transformer offer many advantages over a conventional laminated transformer.Toroidal has a round shape with no air gaps, and with the primary and secondary windings uniformly ditributed around the core, "locks in" the magnetic field and makes the toroidal transformer very quiet and efficient.
Toroidal Transformer, by meeting today"s requirements for smaller, more efficient, quieter and safer products, are being accepted in an increasing range of electronic and electrical equipment.With toroidal transformer smaller dimensions, lighter weight and low stray magnetic fields, you can build more compact, lower cost quality products without sacrificing performance.

Basics of Toroidal TransformerToroidal transformers are built around a ring-shaped core, which, depending on operating frequency, is made from a long strip of silicon steel or permalloy wound into a coil, powdered iron, or ferrite core. A strip construction ensures that the grain boundaries are optimally aligned, improving the transformer's efficiency by reducing the core's reluctance. The closed ring shape eliminates air gaps inherent in the construction of an E-I core. The cross-section of the ring is usually square or rectangular, but more expensive cores with circular cross-sections are also available. The primary and secondary coils are often wound concentrically to cover the entire surface of the core. This minimizes the length of wire needed, and also provides screening to minimize the core's magnetic field from generating electromagnetic interference.

The purpose of this Transformer is to match the Impedance of the loudspeaker or a number of loudspeakers to the optimum load of the tube or transistor. In other words, the transformer transforms the Impedance of the speaker, so that the impedance which it presents to the primary winding is equal to the load of the Output stage active element (tube to transistor).

• Dual Outputs: 4 & 8 Ohms.
• Maximum Ambient Temperature: 40 deg C.
• Frequency Response: 40Hz to 20, 000Hz (-2dB).
• Connections: 150 +/- 10mm multi stranded PVC wire. Stripped and Tinned.

Transformer refers to the static electromagnetic setting which can transfer power from one circuit to another one. In AC circuits, AC voltage, current and waveform can be transformed with the help of Transformers. Each transformation is usually to transfer from one circuit to another one by the way of electromagnetism, but it has no direct relation with this circuit. It also can be transformed through electromagnetism (electrical manner). This electromagnetism is known as auto-transformer.

Basics of E & I TransformersTransformer plays an important role in electronic equipment. AC and DC voltage in Power supply equipment are almost achieved by transformer’s transformation and commutation. At the same time the electrical parameters transformed by transformer are not one but a few ones.
Simple schematic diagram of the transformer is shown below. It is connected by closed-magnet (iron cores), two windings and AC power supply. The winding is called the primary winding; another winding is connected with load, and it is called secondary windings
No-load state of Transformer: viz. the disconnecting state between the secondary winding and load (Figure 1-2). Connect the primary winding and the power supply of AC voltageU1, and then it will produce alternating current I0, this current is called no-load currents. This current set up alternating magnetic flowf0 which is closed along iron core magnetic circuit. At the same time, it traverses the primary winding and secondary winding, and then produces inducting electromotive forceE2 (secondary no-load voltage).

Vritti Associates design and manufacture Power Transformers for a variety of power supply and power conversion applications. Power transformers may be designed in a wide variety of shapes and sizes.

Design requirements for a Power Transformers :
Typical minimum requirements to be specified for a Power Transformer are:

• Power rating in VA.
• Frequency usually 60 Hz.
• Number of primary windings.
• Number of secondary windings.
• Operating voltages levels.
• Operating current levels
• Operating frequency is needed for core calculations and wire sizing.
• Core material is selected for the known operating frequency or frequencies which is typically silicon steel laminations.
• Other Power transformer design considerations are space limitations and mounting technique.
• Lead terminations are also specified through the design of a Power Transformer.

Power transformer designs vary widely in terms of power rating, voltage and current levels (turns ratios), operating frequency, size, impedance, bandwidth (frequency response), winding and other parameters.