FIELD OF THE INVENTION
Development of Toroid 5 roid for electronic component
BACKGROUND OF THE INVENTION
There was a requirement of a critical power supply unit in a system for
aircraft .The space inside the power supply unit was a constraint and one
transformer is to be developed for the power supply unit in which input will be
115 V, 400 Hz , 1 ac . The outputs should be 23-29 V, 470mA, auto tapping of
Input Primary Supply, 40-56 V ,11mA, 45-56 V ,540mA & 10.4-11.7 V, 5mA, .
The Magnetizing Current to be < 4.0 mA . The transformer to be developed
should be small in size. To achieve the given parameters , the development of
such a critical transformer was conceptualized in which ring cores was selected
to confine the size of the toroid within the power supply unit . The developed
Toroid is a sub assembly of power supply unit in which input is 115 V, 400 Hz,
Single Phase Supply. The outputs of the Toroid are rectified, smoothed and
stabilized to supply the restrictors and the DC supply rails of the system for the
electronic cards.
SUMMARY OF PRESENT INVENTION
The Toroid will be used in power supply unit .The Toroid is a sub assembly
of power supply unit .The Toroid is supplied with 115 V, 400 Hz , Single Phase
Supply. An auto-tapping of the Primary Supplies 26 VAC provides both the gyro
motor supplies and both gyro and manometric unit pick-off supplies of the
system. The outputs of the three secondary windings are i.e 26V-20V-0-20V-26V
, 24V-0-24V, 11V AC are fed into the power supply unit where they are rectified,
smoothed and stabilized to supply the restrictors and the DC supply rails of the
system. The Toroid is assembled which requires specialized skill to assemble
because the space inside the core is less and number of winding turns are very
high. There are total nine windings in the Toroid. The windings of the Toroid are
vacuum impregnated with the varnish suitable for power transformer. The design
of the Toroid is optimized so that the power loss is very low. With the
development of Toroid , it saves valuable time as well as cost of the Power
Supply unit .
Annexure‐II
Page 2 of 3
In accordance with one aspect of present invention, due to present invention the
assembly duration of the Toroid 40 roid reduces and in turn saves time .
In accordance with second aspect of present invention, the Toroid is assembled
with discrete components manufactured in house thus saves
cost of the unit.
In accordance with another aspect of present invention, the Toroid is assembled
with skill in such a way that the power loss is very low and due
to this temperature around the assembly not increases and in
turn keep the Power supply unit cool thus enhances the performance of the Power supply unit.
In accordance with yet another aspect of present invention, the Toroid is light in
weight and thus reduces the overall weight of the Power supply
unit
BRIEF DESCRIPTION OF THE DRAWINGS
The features and advantages of the present invention will become more apparent
and descriptive in the description when considered together with figures
presented:
Fig. 1 is an Isometric View
Fig. 2 is an Electrical Winding View
Fig. 3 is an Electrical Circuit Diagram
DETAILED DESCRIPTION
The developed Toroid is assembled which requires specialized skill to assemble
because the space inside the core is less and number of winding turns are very
high. There are total nine windings in the developed Toroid. The design of the
Toroid is optimized so that the power loss is very low . With the development of
Toroid , it saves valuable time as well as cost of the Power Supply unit .The
Toroid will be used in power supply unit in a system for aircraft . The Toroid is a
sub assembly of the power supply unit .The Toroid is supplied with 115 V, 400 Hz
, Single Phase Supply. An auto-tapping of the Primary Supplies 26 VAC provides
both the gyro motor supplies and both gyro and manometric unit pick-off supplies
of the system. The outputs of the three secondary windings are i.e 26V-20V-0-
20V-26V , 24V-0-24V, 11V AC are fed into the power supply unit where they are
rectified, smoothed and stabilized to supply the restrictors and the DC supply
rails of the system. The windings of the Toroid are vacuum impregnated with the
varnish suitable for power transformer. Due to vacuum impregnation, the inter
winding insulations are very high, no air residue inside the windings and excellent
Annexure‐II
Page 3 of 3
power dissipation management. The design of the Toroid is optimized so that the
power loss is very low and in turn enhances the performance of Power supply
unit even in severe hot environment. The cores inside the Toroid are assembled
in such a way that their interfacing faces are glued with the help of a specialized
tools. The developed Toroid have designed in such a way that it will withstand
surrounding high temp (Military Grade), Humidity & Electrical insulation. The
eddy current loss and hysterisis loss are very less. The technical characteristic
are as follow:
INPUTS AND OUTPUTS :
Input : A: 115 V ± 3% , 400 Hz ± 5 Hz, Single Phase Power Supply
Outputs:
B: 23-29 V, 470mA, 400 Hz auto tapping of Input Primary Supply
C: 40-56 V , 11mA, 400 Hz
D: 45-56 V , 540mA, 400 Hz
E: 10.4-11.7 V, 5mA, 400 Hz
Magnetizing Current : < 4.0 mA
INSULATION RESISTANCE :
The insulation resistance between each other windings and screw is to be
greater than 100 MΩ at 500 V ± 40 V DC.
PHYSICAL SPECIFICATION :
Dimensions:
Height (Without terminals ) : ≤ 36 mm (Approx.)
Width : ≤ 55 mm (Approx.)
Length : ≤ 60 mm (Approx.)
Weight : ≤ 250 gm (Approx.)

WE CLAIMS:-
Accordingly, the description of the present invention is to be considered as illustrative only and is for the purpose of teaching those skilled in the art of the best mode of carrying out the invention. The details may be varied substantially without departing from the spirit of the invention, and exclusive use of all modifications which are within the scope of the appended claims is reserved. We Claim that this Toroid

1. are of use for airborne application.
2. Toroid is supplied with 115 V, 400 Hz , Single Phase Supply.
3. Outputs are :
- 23-29 V, 470mA, 400 Hz auto tapping of Input Primary Supply
- 40-56 V , 11mA, 400 Hz
- 45-56 V , 540mA, 400 Hz
- 10.4-11.7 V, 5mA, 400 Hz

4. Magnetizing Current : < 4.0 mA
5. The insulation resistance between each other windings, frame and screw is to be greater than 100 MO at 500 V ± 50 V DC.

6. The Toroid comply with military grade standard

7. The efficiency is more than 98%

8. The power loss is less than one watt. ,TagSPECI:As per Annexure-II