TECHNICAL FIELD
[0001] The present invention relates generally to a system for realizing the multiple winding transformer with high voltage isolation and reduced parasitic.
BACKGROUND
[0002] One of the conventional techniques discloses about transformer winding technique with reduced parasitic capacitance effects. It describes about a winding technique for a step-up transformer. Here the parasitic capacitance effects are substantially minimized by winding the primary coil in the sectional bobbin and winding direction is opposite to the winding direction of the secondary coil. The opposite winding directions allow the high-voltage terminal ends of the primary and the secondary coils to be maximally separated. The maximal separation of high-voltage signals within each coil reduces the effects of the capacitive coupling between the coils, and also maximizes the breakdown voltage between the coils.
[0003] Further, another conventional technique discloses about a low intra-winding capacitance multiple layer transformer winding. Here, the transformer is wound with multiple layers of the same number of turns extending across the bobbin and with the leads from each layer brought out through each end of the bobbin. The individual layers are wound with each turn immediately abutting the preceding turn and successive layers are wound on top of each other so that the turns of the upper layer lie in the furrows or valleys between the turns of the layer immediately below. The distance between the wires of the underlying and overlying layers normal to the bobbin surface is less than the diameter of the wire, and to overcome this difficulty each lead is arranged in echelon with the lead above and below it. Further, a FRA plot for a transformer without bank winding as per the current state of the art is explained herein in Fig. 4.
[0004] There is still a need of an invention which solves the above defined problems.

SUMMARY
[0005] This summary is provided to introduce concepts related to a system for realizing the multiple winding transformer with high voltage isolation and reduced parasitic.
[0006] One of the various embodiments herein include a system that provides realization of multiple winding transformer with high voltage isolation and reduced parasitic. This kind of transformer is a part of grid converter for generating drive and bias voltage levels for controlling the electrode of a high voltage vacuum tube. Here the grid voltages is generated with reference to the cathode terminal of high voltage vacuum tube where several thousands of volts is applied to the cathode terminal. Thus, high voltage isolation is required between primary and secondary windings where primary windings is energised with a ground referenced source. Further, the main requirement of the converter is to have minimum switching spikes on both the primary side switches and the secondary side rectifiers which improves the reliability of the grid converter. Further, the switching spikes mainly depends on the leakage inductance and distributed capacitance of the transformer. Hence, a multiple winding transformer with high voltage isolation and reduced parasitic is realized for the grid converter.
[0007] In another implementation, the system provides a high frequency multiple secondary transformer winding technique that comprises of a combination of bank winding and multi-filar winding techniques. It further comprises of a use of core of closed geometry and use of high voltage wires to achieve high voltage isolation. Further, the transformer is realized with less than 1nF of winding capacitance and leakage inductance of less than 1.8% of primary magnetizing inductance. The isolation achieved for the transformer is up to 25 kilo volt. Further, the transformer is realized with a core of closed geometry results in reduced EMI radiation.
[0008] In another implementation, the bank winding technique is used for the secondary windings where turns are wound in more than one layer. The winding capacitance of less than 1nF and leakage inductance of less than 1.8% of primary magnetizing inductance is achieved for the transformer with multiple secondary windings. Further, the low voltage and high voltage windings are wound in multi-filar pattern for achieving good coupling. The closed geometry core is used for good noise susceptibility and the high voltage wires are used for all windings to get up to 25 kilo volts isolation.
BRIEF DESCRIPTION OF ACCOMPANYING DRAWINGS
[0009] The detailed description is described with reference to the accompanying figures. In the figures, the left-most digit(s) of a reference number identifies the figure in which the reference number first appears. The same numbers are used throughout the drawings to reference features.
[0010] Figs. 1 and 2 illustrates the usage of a bank winding technique, according to an exemplary implementation of the present disclosure.
[0011] Fig. 3 illustrates the primary side winding lead outs which are taken on one side and the secondary winding lead outs which are taken on the other side, according to an exemplary implementation of the present disclosure.
[0012] Fig. 4 illustrates a FRA plot for a transformer without a bank winding as per the current state of art, according to an exemplary implementation of the present disclosure.
[0013] Fig. 5 illustrates a FRA plot for a transformer with a bank winding, according to an exemplary implementation of the present disclosure.
[0014] It should be appreciated by those skilled in the art that any block diagrams herein represent conceptual views of illustrative methods embodying the principles of the present disclosure. Similarly, it will be appreciated that any flow charts, flow diagrams, and the like represent various processes which may be substantially represented in computer readable medium and so executed by a computer or processor, whether or not such computer or processor is explicitly shown.
DETAILED DESCRIPTION
[0015] The various embodiments of the present disclosure provide a system for realizing the multiple winding transformer with high voltage isolation and reduced parasitic.
[0016] In the following description, for purpose of explanation, specific details are set forth in order to provide an understanding of the present claimed subject matter. It will be apparent, however, to one skilled in the art that the present claimed subject matter may be practiced without these details. One skilled in the art will recognize that embodiments of the present claimed subject matter, some of which are described below, may be incorporated into a number of systems.
[0017] However, the systems and methods are not limited to the specific embodiments described herein. Further, structures and devices shown in the figures are illustrative of exemplary embodiments of the presently claimed subject matter and are meant to avoid obscuring of the presently claimed subject matter.
[0018] Furthermore, connections between components and/or modules within the figures are not intended to be limited to direct connections. Rather, these components and modules may be modified, re-formatted or otherwise changed by intermediary components and modules.
[0019] In one embodiment herein, the system provides realization of multiple winding transformer with high voltage isolation and reduced parasitic. This kind of transformer is a part of grid converter for generating drive and bias voltage levels for controlling the electrode of a high voltage vacuum tube. Here the grid voltages is generated with reference to the cathode terminal of high voltage vacuum tube where several thousands of volts is applied to the cathode terminal. Thus, high voltage isolation is required between primary and secondary windings where primary windings is energised with a ground referenced source. Further, the main requirement of the converter is to have minimum switching spikes on both the primary side switches and the secondary side rectifiers which improves the reliability of the grid converter. Further, the switching spikes mainly depends on the leakage inductance and distributed capacitance of the transformer. Hence, a multiple winding transformer with high voltage isolation and reduced parasitic is realized for the grid converter.
[0020] In another embodiment, the system provides a high frequency multiple secondary transformer winding technique that comprises of a combination of bank winding and multi-filar winding techniques. It further comprises of a use of core of closed geometry and use of high voltage wires to achieve high voltage isolation. Further, the transformer is realized with less than 1nF of winding capacitance and leakage inductance of less than 1.8% of primary magnetizing inductance. The isolation achieved for the transformer is up to 25 kilo volt. Further, the transformer is realized with a core of closed geometry results in reduced EMI radiation.
[0021] In another embodiment, the bank winding technique is used for the secondary windings where turns are wound in more than one layer. The winding capacitance of less than 1nF and leakage inductance of less than 1.8% of primary magnetizing inductance is achieved for the transformer with multiple secondary windings. Further, the low voltage and high voltage windings are wound in multi-filar pattern for achieving good coupling. The closed geometry core is used for good noise susceptibility and the high voltage wires are used for all windings to get up to 25 kilo volts isolation.
[0022] It should be noted that the description merely illustrates the principles of the present invention. It will thus be appreciated that those skilled in the art will be able to devise various arrangements that, although not explicitly described herein, embody the principles of the present invention. Furthermore, all examples recited herein are principally intended expressly to be only for explanatory purposes to help the reader in understanding the principles of the invention and the concepts contributed by the inventor to furthering the art and are to be construed as being without limitation to such specifically recited examples and conditions. Moreover, all statements herein reciting principles, aspects, and embodiments of the invention, as well as specific examples thereof, are intended to encompass equivalents thereof.
[0023] Referring now to Figs. 1 and 2, they illustrate the usage of a bank winding technique, according to an exemplary implementation of the present disclosure. The winding is wound with bank winding technique as the number of turns are more and needs to be wound in multiple layers. Further, in a two layer bank winding, the first turn is wound as usual and turns 2nd, 4th, 6th, 8th, so on... are wound in first layer. Furthermore, the turns 3rd, 5th, 7th, 9th so on... are put in second layer. A suitable adhesive is used between the turns to keep the bank winding pattern intact in case of wires with slippery surface are used for winding. Further, a similar procedure is used for remaining secondary windings also wherein the turns are required to be wound in more than one layer.
[0024] Fig. 3 illustrates the primary side winding lead outs which are taken on one side and the secondary winding lead outs which are taken on the other side, according to an exemplary implementation of the present disclosure. The transformer is having multiple secondary windings. Out of the multiple secondary windings, some secondary windings with fewer number of turns are wound in a multi-filar pattern with primary winding in a single layer, remaining secondary windings are wound with bank winding technique in subsequent layers. Further, a closed geometry core is used for the transformer. All of the windings are wound with high voltage wires. Furthermore, few layers of high voltage insulation tape are wrapped over the multi-filar winding to maintain a uniform surface.
[0025] Fig. 4 illustrates a FRA plot for a transformer without bank winding as per the current state of the art, according to an exemplary implementation of the present disclosure. In this, both the magnitude and phase angle variations with frequency can be obtained.
[0026] Fig. 5 illustrates a FRA plot for a transformer with bank winding, according to an exemplary implementation of the present disclosure. In this, it measures the magnitude and phase of the output as a function of frequency. Here, a plurality of values for the magnitude are provided and also the values for leakage inductance and winding capacitance are provided.
[0027] The foregoing description of the invention has been set merely to illustrate the invention and is not intended to be limiting. Since modifications of the disclosed embodiments incorporating the substance of the invention may occur to person skilled in the art, the invention should be construed to include everything within the scope of the invention.
,CLAIMS:
1. A multiple secondary transformer comprising:
a plurality of secondary windings;
a combination of a bank winding pattern and a multifilar winding pattern;
a core of closed geometry; and
a plurality of high voltage wires.

2. The transformer as claimed in claim 1, wherein out of the plurality of secondary windings, part of the plurality of secondary windings having fewer number of turns are wound in the multifilar winding pattern with a primary winding in a single layer and remaining part of the plurality of secondary windings are wound with the bank winding pattern in subsequent layers.

3. The transformer as claimed in claim 2, wherein the multifilar winding pattern is wrapped over by a high voltage insulation tape wherein the high voltage insulation tape is configured to maintain a uniform surface.

4. The transformer as claimed in claim 1, wherein the plurality of secondary windings are wound with the high voltage wires.

5. The transformer as claimed in claim 1, wherein the plurality of secondary windings wound in the multifilar winding pattern is configured to achieve good coupling.

6. The transformer as claimed in claim 1, wherein the combination of the bank winding pattern and the multifilar winding pattern is configured to achieve reduced parasitic.

7. The transformer as claimed in claim 1, wherein the core of closed geometry is configured to achieve reduced EMI radiation.

8. The transformer as claimed in claim 1, wherein the plurality of high voltage wires is configured to achieve high voltage isolation.

9. The transformer as claimed in claim 8, wherein the high voltage isolation is achieved up to 25 kilo volt.

10. The transformer as claimed in claim 1, wherein the transformer is realized with a winding capacitance of less than 1nF and leakage inductance of less than 1.8% of a primary magnetizing inductance.