Power supply unit of furnace

Abstract

A power supply unit (100A, 100B) designed to address multiple challenges, including space constraints, pitting corrosion, short-circuit risks, dust accumulation, power loss, and operational inefficiencies The PSU comprises of a staggered input-busbar assembly in the input section (102), a converter section (104) with variable pulse configurations, thyristor and free-wheel diode stacks, a converter connector (106), and an inverter section (108) with inverter thyristor stacks and inverter connectors (110). Additionally, it includes a cooling system (112) with sub-manifolds, a card rack section (114), a single-window control system, and a modular segmented panel (116). These features collectively ensure optimal performance, reliability, and ease of maintenance, making the unit highly efficient and safe for various industrial applications. The designed power supply unit results in a reduction of approx. 24% of space consumption, approx. 32% of weight reduction and significant reduction in power losses.

Description

POWER SUPPLY UNIT OF FURNACEFIELD OF INVENTION

[0001] The embodiments of present disclosure are in general related to electric furnace and more particularly not exclusively related to the design of power supply unit for electric furnace. The present invention discloses an effective design of power supply unit having enhanced safety quotient.BACKGROUND

[0002] The electric furnaces, preferably induction furnaces, are widely used for melting various metals, their derivatives and different grades. These furnaces offer versatile melting capacities, ranging from a few kilograms to 100 metric tons per batch, making them an essential choice across multiple industries.

[0003] The power supply is a crucial component of a furnace, playing a vital role in ensuring its efficient operation. The power rating requirements determine the number and size of associated components, including parts, equipment, and assemblies. As the kilowatt rating increases, the associated component portfolio size also increases, leading to larger and bulkier power supply units, which poses the challenges in terms of space constraints, maintenance, safety and operational efficiency.

[0004] Further, the different sized panels as well as higher component portfolio undergoes pitting corrosion. Furthermore, corrosion of panel body varies based on type of industry, type of metal, its grades, and metallurgical process for which it is used. The minor to major risk of electrical failure occurs due to accumulation of corroded products, dust, and dirt on panel body. Also, closed panel enclosure does not permit regular inspection of various components / assembly / water circuit. Panel comprises of number of compartments and multiple assemblies such as converter assembly, inverter assembly involves higher length of busbars causes more electrical losses.Owing to the large size and involvement of number of assemblies of panel result in difficulty maintaining cleanness as well as integrity of panel. Also, the aesthetic appearance and safety quotient are not appropriate.

[0005] The disclosure of the present invention provides the solution to resolve the above problems.SUMMARY

[0006] The present invention of the Power Supply Unit (PSU) is preferably designed for electric furnaces for melting various metals and alloys. Furthermore, it can be preferred in other metal forming processes such as hardening, heating, welding, brazing, and so on. The embodiment of present invention discloses the power supply unit having optimal design and arrangement of sections and assemblies that enhance operational efficiency.

[0007] The power supply unit comprises of an input section having at least a staggered input-busbar assembly, a converter section with varying pulse configuration, a converter connector, an inverter section having inverter thyristor stacks, an inverter connector, a cooling system, a card rack section and a modular segmented panel.

[0008] In an embodiment, an input section is preferably an athwart staggered busbar assembly for connection between the converter section and secondary transformer. A athwart staggered busbar assembly comprises of at least a metal contact plate, at least a coupled current transformer (CT), at least a long-link busbar, at least a fuse and at least a flexible link busbar. The coupled current transformer further comprises of a line CT to measure a line current of each phase, and protection CT to protect converter circuit. The coupled CT preferably arranges on the contact plate which connects through long-link busbar to fuse that further connects to flexible link busbar. The flexible busbars connect with the Converter Thyristor stack. The long-link busbars are hollow metal tubes having extensions for cooling connectors. The athwart staggeredarrangement of busbars optimized the length requirement of busbars that results in reduction of the (I2R) power losses.

[0009] In an embodiment, a converter section of varying pulse configurations comprises of at least a converter thyristor stack, at least a free wheel diode stack, a converter firing circuit, and a Resistor Capacitor snubber circuit.

[0010] The converter section, preferably of 24 pulse configuration consists of six sets of a converter thyristor stacks where each converter thyristor stack is an assembly of four thyristors arranged in series, and two free wheel diode stacks. Alternatively, for 24 pulse configurations consists of four sets of converter thyristor stacks where each converter thyristor stack is an assembly of six thyristors arranged in series can be preferred. Further, depending on the power and optimum harmonics requirement, the pulse configurations can be preferred from 6 to 48 and accordingly the number of a converter thyristor stacks, associated thyristors and components can be preferred.

[0011] A converter thyristor stack is an assembly of a set of four press pack thyristors; each arranged between chiller plates which are further supported by insulation sheets to avoid the risk of short-circuit. These four sets are further supported by pressure-blocks and disc springs. Subsequently, these sets are placed in between top pressure plate and bottom pressure plate. This arrangement of converter thyristor stacks reduces the number of components such as insulation plates, pressure blocks, pressure plates and space requirement.

[0012] The free wheel diode stack is preferably arranged alongside the converter thyristor stack. The free-wheel diode stack is an assembly of a set of diodes arranged in a same manner to a thyristor stack. In embodiments, preferably the press pack thyristors are used, however any other alternative can be used to serve the purpose of invention.

[0013] Each converter thyristor stack is driven through the respective firing circuit and each thyristor has a resistor capacitor snubber circuit to protect thyristor device from voltage spikes (dv / dt). The converter firing circuits arepreferably digital circuits with fibre optics signals to nullify electromagnetic interference. Alternatively, digital circuits with electric signals or analogue circuits also can be preferred. Further, in another embodiment, thyristors and diodes can alternatively be used in converter thyristor stacks and free wheel diode stacks.

[0014] In an embodiment, an inverter section comprises at least an inverter thyristor stack, an inverter firing circuit, a resistor capacitor snubber and sharing resister circuit. For 24 pulse configurations, the inverter section preferably consists of four inverter thyristor stacks and each inverter thyristor stack includes at least an inverter thyristor or assembly of multiple inverter thyristors in series. Depending on the output voltage requirement, the number of an inverter thyristor stacks and thyristors can be preferred.

[0015] An inverter thyristor stack is an assembly of at least a press pack inverter thyristors arranged between chiller plates which are supported by insulation sheets to avoid the risk of short-circuit. These sets are further supported by pressure-blocks and disk spring. Subsequently, these sets are placed in between top pressure plate and bottom pressure plate.

[0016] In an embodiment, a converter connector and an inverter connector are assembly of contact plates with the long-link hollow busbars having extensions for cooling connectors. The converter connector connects the variable DC output of the converter section to a DC Choke to filter the ripples and provides the stable DC current while the inverter connector connects the stable DC output of DC Choke to the inverter section. The contact plates have preferably bolting connections, alternatively riveting or any other connecting means can be used to serve the purpose of invention. The contact plates preferably solid metal plates, alternatively sandwich contact plates or other means can be used to serve the purpose of invention.

[0017] In an embodiment, a cooling system comprises an inlet header manifold, outlet header manifold, a vertical sub-manifold, flow switches to monitor flow of water, conductivity sensors to check measure quality of water,temperature sensors (RTD) to monitor temperature of water. The vertical submanifold enables the closure cooling connections and reduces the unnecessary piping and plumbing connections. The cooling system provides the cooling to thyristor devices in converter, inverter, fuses of circuit, Snubber circuits, Busbar Connectors, DC Choke by circulating demineralized water.

[0018] In an embodiment, a Card Rack section is a single window section arranged on Power Supply Unit. The Card Rack section comprises of Control Plate assembly, and control transformer section. The Card Rack section has the control circuit to control the induction melting furnace, whereas all furnace electrical parameters are measured and controlled within their predefined threshold rated value. It also includes trip and interlock section ensure healthiness of induction furnace operation. The Card Rack section enables the controlling and operating of furnaces from anywhere using techniques such as Internet of Things (loT), Wireless communication, Could Computing etc.

[0019] In an embodiment, a modular segmented panel is an enclosure preferably for the input section, the converter section, the converter connector, the inverter section, the inverter connector, the cooling system and the card rack section. The modular segmented panel has a metallic body with a transparent glass panel. The modular segmented panel provides the rigid support and a steady place for electronic circuit components. Further, it protects the power supply system from outside dust and humidity. And also protect to human from electrical high power and voltage.

[0020] The designed power supply unit described in embodiments The embodiments of the invention are prone to numerous modifications and variations, all of which are within the scope of the same inventive concept. Further, the assembly, components, parts, composition, arrangements, position of devices used may of course be replaced / altered with other technically equivalent ones; the steps may furthermore be performed in a different sequenceBRIEF DESCRIPTION OF DRAWINGS

[0021] The accompanying drawings, incorporated in the present disclosure and constituting a part of the same, illustrate the exemplary embodiments. The drawings, together with the description, serve to explain the disclosed principles. Some embodiments of the present subject matter are now described by way of example only and with reference to the accompanying figure, in that:

[0022] Figure 1A illustrates a Power Supply Unit in accordance with some embodiments of the present disclosure (100A); and

[0023] Figure IB illustrates a rear view of Power Supply Unit in accordance with some embodiments of the present disclosure (100B); and

[0024] Figure 2 illustrates an Input Section (200) of Power Supply Unit in accordance with some embodiments of the present disclosure

[0025] Figure 3 illustrates a Converter section (300) of Power Supply Unit

[0026] Figure 4 illustrates a Converter Thyristor Stack (400) of Converter Section of Power Supply Unit

[0027] Figure 5 illustrates an Inverter Section (500) of Power Supply Unit

[0028] Figure 6 illustrates an Inverter Thyristor Stack (600) of Inverter Section of Power Supply Unit

[0029] Figure 7A illustrates a Converter Connector (700A) of Power Supply Unit

[0030] Figure 7B illustrates an Inverter Connector (700B) of Power Supply Unit

[0031] Figure 8 illustrates a Cooling System (800) of Power Supply Unit

[0032] Figure 9 illustrates a Card Rack Section (900) of Power Supply Unit

[0033] Figure 10 illustrates a Modular Segmented Panel (1000) of Power Supply UnitDETAILED DESCRIPTION OF DRAWINGS

[0034] In the present disclosure, the word "exemplary" is used herein to mean as an example, instance, or illustration. Any embodiment or implementation of the present subject matter described as "exemplary" is not necessarily to be construed as preferred or advantageous over other embodiments.

[0035] While the disclosure is susceptible to various modifications and alternative forms, specific embodiments thereof have been shown by way of example in drawings and will be described in detail below. However, it should be understood that it is not intended to limit the disclosure to the particular form disclosed; on the contrary, the disclosure is intended to cover all modifications, equivalents, and alternatives falling within the spirit and the scope of the disclosure.

[0036] The terms "comprises," "comprising," or any other variations thereof are intended to cover a non-exclusive inclusion, such that a setup, device, or method that comprises a list of components or steps does not include only those components or steps but may include other components or steps not expressly listed or inherent to such a setup or device or method. In other words, one or more elements in a device or system or apparatus preceded by "comprises... a" do not, without more, constrain the system or apparatus.

[0037] In the following detailed description of the embodiments of the disclosure, reference is made to the accompanying drawings that form a part hereof and that are shown by way of illustration of specific embodiments in which the disclosure may be practiced. These embodiments are described in sufficient detail to enable those skilled in the art to practice the disclosure, and it is to be understood that other embodiments may be utilized, and changes may be made without departing from the scope of the present disclosure. The following description is, therefore, not to be taken in a limiting sense.

[0038] The detailed description of the figures provides a better comprehension of the present invention.

[0039] Figure 1A is an exemplary illustration of the Power Supply Unit (100A) and Figure IB is an exemplary illustration of the rear view of Power Supply Unit.

[0040] The power supply unit (100A and 100B) comprises of an input section (102) having at least a staggered input-busbar assembly, a converter section (104) with varying pulse configuration, a converter connector (106), an inverter section having inverter thyristor stacks (108), an inverter connector (110), a cooling system (112), a card rack section (114) and a modular segmented panel (116). Further, the DC Choke Assembly (120) and di / dt coil assembly (118) are not part of embodiments of present invention but part of power supply unit

[0041] Figure 2 is an exemplary illustration of the input section of Power Supply Unit (200).

[0042] An Input Section of Power Supply Unit (200) is preferably an athwart staggered busbar assembly (202) for connection between the converter section (shown in figure IB) and secondary transformer (not shown in figure). The athwart staggered busbar assembly (202) comprises of at least a contact plate (204), at least a coupled current transformer [CT] (206), at least a long-link busbar (208), at least a fuse (210) and at least a flexible link busbar (212).The coupled current transformer (206) further comprises of a line CT (214) to measure a line current of each phase, and protection CT (216) to protect converter circuit. The coupled CT (206) preferably arranges on the contact plate (204) which connects through long-link busbar (208) to fuse (210) that further connects to flexible link busbar (212). The flexible link busbars (212) connect with the Converter Thyristor stack (shown in figure 3). The long-link busbars (208) are preferably hollow metal tubes having extensions for cooling connectors (218). The athwart staggered arrangement of busbars (202) optimizes the length requirement of busbars that results in reduction of the I2R power losses.

[0043] Figure 3 is an exemplary illustration of the Converter section (300) of Power Supply Unit.

[0044] The Converter section (300) with varying pulse configurations of Power Supply Unit comprises of at least a converter thyristor stack (302), at least a free wheel diode stack (304), a converter firing circuit (306), and a Resistor Capacitor snubber circuit (308).

[0045] The converter section (300), preferably of 24 pulse configuration consists of six sets of a converter thyristor stack (302), and two free wheel diode stacks (304). Each converter thyristor stack (302) is an assembly of four thyristors arranged in a series. Depending on the power and optimum harmonics requirement, the pulse configurations can be preferred from 6 to 48 and accordingly the number of a converter thyristor stacks (302), associated thyristors and components can be preferred. The free wheel diode stacks (304) are preferably arranged alongside the converter thyristor stack (302).

[0046] Each converter thyristor stack (302) is driven through the respective converter firing circuit (306) and each thyristor has a resistor capacitor snubber circuit (308) to protect thyristors from voltage spikes (dv / dt). The converter firing circuits (306) are preferably digital circuits with fibre optics signals or analog circuits to nullify electromagnetic interference. Alternatively, digital circuits with electric signals or analogue circuits also can be preferred. Further, in another embodiment, thyristors and diodes can alternatively be used in converter thyristor stacks (302) and free wheel diode stacks (304).

[0047] Figure 4 is an exemplary illustration of the Converter Thyristor Stack (400) of Converter Section of Power Supply Unit.

[0048] A converter thyristor stack (400) is an assembly of a set of four press pack thyristors (402); each arranged between chiller plates (404) which are further supported by insulation sheets (406) to avoid the risk of short-circuit. These four sets are further supported by pressure-blocks (408) and disc spring (410). Subsequently, these sets are placed in between the top pressureplate (412) and bottom pressure plate (414) and pressurized using the fastenings. This arrangement of converter thyristor stacks (400) reduces the number of components such as insulation plates (406), pressure blocks (408), and pressure plates (412 and 414) and space requirement. The free-wheel diode stacks (shown in figure 3) are an assembly of a set of diodes arranged in a same manner as a converter thyristor stack (400). In embodiments, preferably the press pack thyristors (402) are used, however other alternatives can be used to serve the purpose of invention.

[0049] Figure 5 is an exemplary illustration of the Inverter Section (500) of Power Supply Unit.

[0050] The Inverter Section (500) of power Supply Unit comprises at least an inverter thyristor stack (502), an inverter firing circuit (504), a resistor capacitor snubber and sharing resister circuit (506). For 24 pulse configurations, the inverter section (500) preferably consists of four inverter thyristor stacks (502) and each inverter thyristor stack includes at least an inverter thyristor or assembly of multiple inverter thyristors in series. Depending on the output voltage requirement, the number of an inverter thyristor stacks (502) and thyristors can be preferred.

[0051] Figure 6 is an exemplary illustration of the Inverter Thyristor Stack (600) of Inverter Section of Power Supply Unit.

[0052] An inverter thyristor stack (600) is an assembly of at least a press pack inverter thyristor (602) arranged between chiller plates (604) which are supported by insulation sheets (606) to avoid the risk of short-circuit. These sets are further supported by pressure-blocks (608) and disk spring (610). Subsequently, these sets are placed in between top pressure plate (612) and bottom pressure plate (614) and pressurized using the fastenings.

[0053] Figure 7A is an exemplary illustration of the Converter Connector (700A) of Power Supply Unit and Figure 7B is an exemplary illustration of the Inverter Connector (700B) of Power Supply Unit.

[0054] The converter connector (700A) and an inverter connector (700B) are assembly of contact plates (702) with the long-link hollow busbars (704) having extensions for cooling connectors (706). The converter connector (700A) connects the variable DC output of the converter section (shown in Figure IB) to a DC Choke (shown in Figure 1A) to filter the ripples and provide the stable DC current while the inverter connector (700B) connects the stable DC output of DC Choke (shown in Figure 1A) to the inverter section (708). The contact plates (702) have preferably bolting connections, alternatively riveting or any other connecting means can be used to serve the purpose of invention. Also, the contact plates (702) preferably solid plates, alternatively sandwich contact plates or other means can be used to serve the purpose of invention.

[0055] Figure 8 is an exemplary illustration of the Cooling System (800) of Power Supply Unit.

[0056] The cooling System (800) comprises an inlet header manifold (802), outlet header manifold (804), a vertical sub-manifold (806), flow switches (808) to monitor flow of water integrated with the conductivity sensors to check measure quality of water, temperature sensors (RTD) to monitor the temperature of water. The vertical sub-manifold (806) enables the closure cooling connections and reduces the unnecessary piping and plumbing connections. The cooling system (800) provides the cooling to thyristor devices in converter, inverter, fuses of circuit, Snubber circuits, Busbar Connectors, DC Choke by circulating demineralized water (shown in Figure 1A and IB).

[0057] Figure 9 is an exemplary illustration of the Card Rack Section (900) of Power Supply Unit.

[0058] The Card Rack section (900) is a single window section arranged at either side of Power Supply Unit. The Card Rack section (900) comprises Control Plate assembly (902), Internal Control Assembly (904) and control transformer section (906). The Card Rack section (900) controls the furnace, whereas all furnace electrical parameters are measured and controlled withintheir predefined threshold rated value. Further, Internal Control Assembly (904) includes trip and interlock sections / arrangements ensure healthiness of furnace operation. The Card Rack section (900) enables the controlling and operating of furnaces from anywhere using techniques such as Internet of Things (loT), Wireless communication, Could Computing etc. In another embodiment, Card Rack Section (900) can be arranged at other position of Power Supply Unit or separately outside the Power Supply Unit.

[0059] Figure 10 is an exemplary illustration of the Modular Segmented Panel (1000) of Power Supply Unit.

[0060] The Modular Segmented Panel (1000) of Power Supply Unit is an enclosure preferably for the input section, the converter section, the converter connector, the inverter section, the inverter connector, the cooling system and the card rack section (shown in figure 1A and IB). The modular segmented panel (1000) provides the rigid support and a steady place for electronic circuit components. Further, it protects the power supply system from outside dust and humidity. And also protect to human from electrical high power and voltage. The Modular Segmented Panel (1000) preferably made of sheet metal having transparent glass panel.

[0061] The designed power supply unit results in a reduction of approx. 24% of space consumption, approx. 32% of weight reduction and reduction in power losses due to reduction in length of busbar requirement and panel components / part requirement. The transparent glass panel provides better Aesthetic appeal along with heat resistance upto 250°C, protection from foreign particles, reduces the rusting / corrosion that further enhances durability. Further, the present design provides the ease of operation and maintenance along with improved safety quotient. The present design enables to design a single panel structure with high power ratings up to 26000 kW.

Claims

CLAIMSI CLAIM:

1. A power supply unit (100A,100B) for a furnace that comprises of:an input section (102, 200) having at least a staggered inputbusbar assembly (202) for connection between the converter section (104) and a secondary transformer, wherein the staggered inputbusbar assembly (202) includes at least a contact plate (204), at least a coupled current transformer [CT] (206), at least a long-link busbar (208), at least a fuse (210) and at least a flexible link busbar (212), wherein the staggered input busbar assembly (202) optimizes the length requirement of busbars that results in reduction of the I2R power losses;a converter section (104, 300) with varying pulse configuration that comprises of at least a converter thyristor stack (302, 400), at least a free wheel diode stack (304), a converter firing circuit (306), and a Resistor Capacitor snubber circuit (308);a converter connector (106, 700A) that is an assembly of contact plates (702) with the long-link hollow busbars (704) having extensions for cooling connectors (706), wherein the converter connector (700A) connects the variable DC output of the converter section converter section (104, 300) to a DC Choke assembly (120) to filter the ripples and provide the stable DC current;an inverter section (500, 708) including at least an inverter thyristor stack (108, 502, 600), an inverter firing circuit (504), a resistor capacitor snubber and a sharing resister circuit (506);an inverter connector (110, 700B) that is an assembly of contact plates (702) with the long-link hollow busbars (704) having extensions for cooling connectors (706), wherein the inverterconnector (700B) connects the stable DC output of DC Choke assembly (120) to the inverter section (500, 708);a cooling system (112, 800) that provides cooling to thyristor devices in converter, inverter, fuses of circuit, snubber circuits, Busbar Connectors, DC Choke of the power supply unit (100A,100B) by circulating demineralized water;a card rack section (114, 900) that is a single window section arranged on atleast one side of the power supply unit (100A,100B), wherein the card rack section (114, 900) is configured to control all furnace electrical parameters within their predefined threshold rated value;a modular segmented panel (116, 1000) that is an enclosure that is configured to provide rigid support for the input section (102, 200), the converter section (104, 300), the converter connector (106, 700A), the inverter section (500, 708), the inverter connector (110, 700B), the cooling system (112, 800) and the card rack section (114, 900).

2. The power supply unit (100A,100B) as claimed in claim 1 wherein the staggered input-busbar assembly (202) is an athwart staggered busbar assembly (202)3. The power supply unit (100A,100B) as claimed in claim 1 wherein the coupled current transformer (206) includes a line CT (214) to measure a line current of each phase, and protection CT (216) to protect converter circuit.

4. The power supply unit (100A,100B) as claimed in claim 1 wherein the coupled current transformer (206) is arranged on the contact plate(204) which connects through long-link busbar (208) to fuse [210) that further connects to flexible link busbar (212).

5. The power supply unit (100A,100B) as claimed in claim 1 wherein the flexible link busbars (212) connect with the Converter Thyristor stack (302,400).

6. The power supply unit (100A,100B) as claimed in claim 1 wherein the long-link busbars (208) are hollow metal tubes having extensions for cooling connectors (218).

7. The power supply unit (100A,100B) as claimed in claim 1 wherein the converter section (300) can be of 6 to 48 pulse configurations.

8. The power supply unit (100A,100B) as claimed in claim 1 wherein the converter section (300), is of 24 pulse configuration that consists of six sets of a converter thyristor stack (302, 400), and two free wheel diode stacks (304).

9. The power supply unit (100A,100B) as claimed in claim 1 wherein the converter thyristor stack (302, 400) is an assembly of four thyristors arranged in a series.

10. The power supply unit (100A,100B) as claimed in claim 1 wherein the free-wheel diode stacks (304) are an assembly of a set of diodes.

11. The power supply unit (100A,100B) as claimed in claim 1 wherein the free wheel diode stacks (304) are arranged alongside the converter thyristor stack (302, 400).

12. The power supply unit (100A,100B) as claimed in claim 1 wherein the converter thyristor stack (302, 400) is driven through the respective converter firing circuit (306) and each thyristor has a resistor capacitor snubber circuit (308) to protect thyristors from voltage spikes (dv / dt).

13. The power supply unit (100A,100B) as claimed in claim 1 wherein the converter firing circuits (306) are digital circuits with fiber optics signals or analog circuits to nullify electromagnetic interference.

14. The power supply unit (100A,100B) as claimed in claim 1 wherein the converter thyristor stack (400) is an assembly of a set of four press pack thyristors (402); each arranged between chiller plates (404)15. The power supply unit (100A,100B) as claimed in claim 13 wherein the chiller plates (404) are supported by insulation sheets (406).

16. The power supply unit (100A,100B) as claimed in claim 13 wherein the of four press pack thyristors (402) are supported by pressure-blocks (408) and disc spring (410).

17. The power supply unit (100A,100B) as claimed in claim 13 wherein the of four press pack thyristors (402) are placed in between the top pressure plate (412) and bottom pressure plate (414) and pressurized using the fastenings.

18. The power supply unit (100A,100B) as claimed in claim 1 wherein the inverter section (500) consists of four inverter thyristor stacks (108, 502, 600) for 24 pulse configurations.

19. The power supply unit (100A,100B) as claimed in claim 1 wherein the inverter thyristor stack (108, 502, 600) includes at least an inverter thyristor (602).

20. The power supply unit (100A,100B) as claimed in claim 1 wherein the inverter thyristor stack (108, 502, 600) includes assembly of multiple inverter thyristors (602) in series.

21. The power supply unit (100A,100B) as claimed in claim 19-20 wherein the inverter thyristors (602) is arranged between chiller plates (604).

22. The power supply unit (100A,100B) as claimed in claim 19-20 wherein the chiller plates (604) are supported by insulation sheets (606).

23. The power supply unit (100A,100B) as claimed in claim 19-20 wherein the inverter thyristors (602) are supported by pressure-blocks (608) and disk spring (610).

24. The power supply unit (100A,100B) as claimed in claim 19-20 wherein the inverter thyristors (602) are placed in between top pressure plate(612) and bottom pressure plate (614) and pressurized using the fastenings.

25. The power supply unit (100A,100B) as claimed in claim 1 wherein the contact plates (702) have bolting connections or riveting or any other connecting means.

26. The power supply unit (100A,100B) as claimed in claim 1 wherein the contact plates (702) are solid plates or sandwich contact plates or other means.

27. The power supply unit (100A,100B) as claimed in claim 1 wherein the cooling System (800) includes an inlet header manifold (802), outlet header manifold (804), a vertical sub-manifold (806), flow switches (808) to monitor flow of water integrated with the conductivity sensors to check measure quality of water, temperature sensors (RTD) to monitor the temperature of water.

28. The power supply unit (100A,100B) as claimed in claim 1 wherein the vertical sub-manifold (806) enables the closure cooling connections to reduce unnecessary piping and plumbing connections.

29. The power supply unit (100A,100B) as claimed in claim 1 wherein the Card Rack section (114, 900) includes Control Plate assembly (902), Internal Control Assembly (904) and control transformer section (906).

30. The power supply unit (100A,100B) as claimed in claim 29 wherein the Internal Control Assembly (114, 900) includes trip and interlock sections / arrangements that are configured to ensure optimum furnace operation.

31. The power supply unit (100A,100B) as claimed in claim 1 wherein the Card Rack section (114, 900) enables the controlling and operating of furnaces using techniques such as Internet of Things (loT), Wireless communication, Could Computing.

32. The power supply unit (100A,100B) as claimed in claim 1 wherein the Card Rack section (114,900) is arranged separately outside the Power Supply Unit (100A, 100B).

33. The power supply unit (100A,100B) as claimed in claim 1 wherein the Modular Segmented Panel (116, 1000) is made of sheet metal having transparent glass panel.

34. The power supply unit (100A,100B) as claim in claim 1 includes the DC Choke Assembly (120) and a di / dt coil assembly (118).

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