Electrical heater power supply system
The system addresses the complexity and cost of existing power supply systems by using variable voltage transformers and switchgear to independently control multiple heating circuits, achieving efficient and cost-effective power management.
Patent Information
- Authority / Receiving Office
- WO · WO
- Patent Type
- Applications
- Current Assignee / Owner
- SHELL INTERNATIONALE RESEARCH MAATSCHAPPIJ BV
- Filing Date
- 2025-12-12
- Publication Date
- 2026-06-25
AI Technical Summary
Existing systems for supplying and controlling electrical power to industrial heaters and thermal energy storage devices are complex and expensive, relying on large power electronics converters and numerous contactors.
A system comprising variable voltage transformers and switchgear with parallel-connected switches allows independent control of multiple heating circuits without the need for large power electronics converters or numerous contactors, enabling power supply control through voltage ratio adjustment and switch operation.
Enables efficient and cost-effective power control to individual heating apparatuses, allowing selective operation or shutdown of heating circuits based on operational parameters, reducing complexity and cost.
Smart Images
Figure EP2025086877_25062026_PF_FP_ABST
Abstract
Description
[0001] S P3207
[0002] Electrical Heater Power Supply System
[0003] Field of the Invention
[0004] This invention relates to an electrical heater power supply system . In particular , this invention relates to an electrical system, to a method, and to a control system for providing electrical power to a plurality heating circuit s .
[0005] Background of the invention
[0006] Industrial electric heaters and thermal energy storage systems are commonly used in a variety of industrial settings including chemical proces sing , water treatment and food proces sing .
[0007] Existing systems for supplying - and controlling the supply of - electrical power to industrial heaters and thermal energy storage devices are complex and expensive , consi sting of large power electronics convertors with a large number of contactors . It is an aim of the current invention to overcome at lea st some of the di sadvantage s of the known systems .
[0008] Summary of the Invention
[0009] According to an aspect of the invention , there is provided an electrical system comprising : one or more power distribution systems , wherein the or each power distribution system comprise s a variable voltage trans former having an input side and an output side , and a switchgear comprising a plurality of switches , wherein the input s ide of the variable voltage transformer is configured to be connected to an electrical power supply in use , and wherein the plurality of switches are connected in parallel to the output side of the variable voltage transformer ; and an electrical heating system compris ing a plurality of electrically powered heating circuit s , wherein each electrically powered heating circuit is connected to one of the plurality of switche s of the switchgear of the , or one of the , power distribution systems such that each electrically powered heating circuit is operable independently of each other electrically powered heating circuit .
[0010] The present invention is advantageous as the power supplied to the electrically powered heating circuit s can be controlled without the need for large power electronics convertors or a large number of contactors .
[0011] Optionally the electrical heating system comprises one or more electrical heating apparatuse s , wherein the or each electrical heating apparatus comprises a plurality of electrically powered heating circuits . This beneficially allows power supply control to the or each heating apparatus by selectively operating or shutting-off the electrically powered heating circuits via their as sociated switche s .
[0012] The or each electrical heating apparatus is optionally connected to its own dedicated power distribution system . This allows for individual control of the power supplied to each heating apparatus by variation of one or both of both the turns ratio of the variable voltage transformer , and / or by selective operation of the electrically powered heating circuits via their as sociated switche s .
[0013] The one or more electrical heating apparatuse s may comprise a heating ve s sel for heating a f luid . In one example the electrical heating system comprises : one or more such heating ves sels ; a cold f luid tank ; a hot fluid tank ; and pipework configured to connect the cold fluid tank to the hot fluid tank via at least one heating ves sel .
[0014] According to another aspect of the invention , there is provided a method of controlling the electrical system of any preceding claim, the method compri sing : receiving one or more control s ignals indicative of one or more operational parameters of the electrical heating system; and adj usting the voltage change ratio acros s one or more of the variable voltage transformers of the one or more power distribution systems ; and / or operating one or more of the switches of one or more of the switchgears of the one or more power distribution systems in dependence on the one or more control signals . The power supplied to the electrically powered heating circuits can therefore advantageously be controlled in dependence on the operational parameters of the electrical heating system .
[0015] The method may compri se operating the switche s of one or more of the switchgears such that one or more of the electrical heating circuits of one or more of the electrically powered heating apparatuses are operational . By operating only selected ones of the electrical heating circuit s the power supplied to the or each heating apparatuse s may be controlled .
[0016] Optionally, when the electrical system compri ses a plurality of electrically powered heating apparatuse s , the method may comprise operating the switche s of one or more of the switchgears such that all of the electrical heating circuit s of one or more of the plurality of electrically powered heating apparatuses are inoperative so that one or more of the heating apparatuses are inoperative . Thi s may be beneficial , for example , if a heating apparatus has a fault , or if it is de sirable for operational reasons to completely shut down one or more of the heating apparatuse s .
[0017] In cases where the electrical system compri se s a plurality of power di stribution systems , the method optionally comprises adj usting the voltage change ratio acros s one or more of the variable voltage transformers of the one or more power distribution systems such that at least one of the variable voltage transformers has a different voltage change ratio to at least one other variable voltage transformer . This beneficially allows a different amounts of power to be provided to different ones of the heating apparatuses .
[0018] According to a further aspect of the invention, there i s provided a control system for controlling the electrical system of any preceding claim, wherein the control system is configured to : receive one or more input control signals indicative of one or more operational parameters of the electrical heating system; and output one or more output control s ignals in dependence on the one or more input control signals , wherein the one or more output control signal s comprise an instruction to : adj ust the voltage change ratio acros s one or more of the variable voltage transformers of the one or more power distribution systems ; and / or operate one or more of the switche s of one or more of the switchgears of the one or more power distribution systems . Brief Description of the Drawings
[0019] Figure 1 schematically illustrates an electrical system for supplying power to an electrical heating system;
[0020] Figure 2 schematically illustrates an alternative electrical system to that shown in Figure 1 ;
[0021] Figure 3 schematically illustrates a further alternative electrical system to that shown in Figures 1 and 2 ;
[0022] Figure 4 shows a flow chart for controlling an electrical system such as that shown in Figures 1 to 3 ; and
[0023] Figure 5 shows a schematic illustration of a control system for controlling an electrical system such as that shown in Figure s 1 to 3 .
[0024] These drawings depict one or more implementations in accordance with the present teachings , by way of example only, not by way of limitation . In the Figure s , like reference numerals refer to the same or s imilar element s .
[0025] Detailed Description of the Drawings
[0026] Figure 1 schematically illustrates a single pha se repre sentation of an electrical system 10 for providing power to an electrical heating system 30 . The electrical system 10 comprises a power distribution system 20 which comprises a variable voltage transformer (WT ) 21 and a switchgear 22 .
[0027] The WT 21 has an input side 23 comprising a primary winding 24 , and an output side 25 compris ing a secondary winding 26 . The input side 23 is connected to an alternating current (AC ) electrical power supply 14 . A tap changing mechanism 27 is arranged on the secondary winding 26. The tap changing mechanism 27 is configured to vary the number of operative turns of the secondary winding 26. The tap changing mechanism 27 may be implemented mechanically or electronically.
[0028] The switchgear 22 comprises four switches 28a, 28b, 28c, 28d which are connected in parallel to the output side 25 of the WT 21.
[0029] In this example, the electrical heating system 30 comprises a heating apparatus 31 which comprises four electrically powered heating circuits 32a, 32b, 32c, 32d. Each electrically powered heating circuit 32a, 32b, 32c, 32d is connected to a switch 28a, 28b, 28c, 28d located within the switchgear 22 so that each electrically powered heating circuit is operable independently of each other electrically powered heating circuit. The electrical heating system 30 also comprises a cold fluid tank 33 and a hot fluid tank 34. In this example the heating apparatus 31 is a heating vessel for heating a fluid.
[0030] The electrical heating system 30 may be used to heat a fluid, such as water or oil. Cold (or unheated) fluid is stored in the cold fluid tank 33. Pipework 35a connects the cold fluid tank 33 to the heating apparatus 31, and pipework 35b connects the heating apparatus 31 to the hot fluid tank 34. Bypass pipework 35c connects the cold fluid tank 33 to the hot fluid tank 34. Control valves 36a, 36b control the flow of fluid in the pipework 35a, 35b, 35c. The electrical heating system 30 may be used to heat a fluid and to store thermal energy in the hot fluid tank 34. In use, the power delivered to the heating apparatus 31 may be controlled by altering the voltage drop across the WT 21, and / or by operating one, two, three or all four of the electrical heating circuits 32a, 32b, 32c, 32d. The voltage drop across the WT 21 may be altered by operating the tap change mechanism 27 to change the number of operative turns on the secondary winding 26 of the WT 21 thereby changing the turns ratio across the WT 21. Alternatively or additionally, the power delivered to the heating apparatus 31 may be controlled by altering the number of operative electrical heating circuits by opening or closing the switches 28a, 28b, 28c, 28d of the switchgear 22.
[0031] Although described above in the context of a single phase view of the electrical system 10, it will be understood that the electrical system 10 may be implemented with a three phase variable voltage transformer arranged in a Wye-Delta configuration, or in any other suitable configuration such as Delta-Delta, Wye- Wye or Delta-Wye. In the description above, and in the description that follows, a single phase views of the electrical systems 10 are shown and described for the sake of simplicity. It will be understood that each electrical system described herein may be implemented with a single phase or three phase transformer.
[0032] Figure 2 schematically illustrates an alternative electrical system 10 to that shown in Figure 1. As for the electrical system described above with reference to Figure 1, the example electrical system 10 shown in Figure 2 comprises a power distribution system 20 which comprises a variable voltage transformer 21 and a switchgear 22. The WT 21 is the same as that described above with reference to Figure 1. However, in this example, the switchgear 22 comprises sixteen switches electrically arranged in four groups 29a, 29b, 29c, 29d of four. The sixteen switches are connected in parallel to the output side 25 of the WT 21. It will be noted that the spatial grouping of the switches shown in Figure 2 is illustrative only, and that the switches need not be physically arranged in groups.
[0033] In this example, the electrical heating system 30 comprises four fluid heating apparatuses 31a, 31b, 31c, 31d, each comprising four electrically powered heating circuits. The electrically powered heating circuits of each heating apparatus 31a, 31b, 31c, 31d are connected to the switches in respective switch groups 29a, 29b, 29c, 29d so that each electrically powered heating circuit in each heating apparatus 31a, 31b, 31c, 31d is operable independently of each other electrically powered heating circuit .
[0034] As described above for Figure 1, the electrical heating system 30 of Figure 2 comprises a cold fluid tank 33 and a hot fluid tank 34. Pipework 35a connects the cold fluid tank 33 to the heating apparatuses 31a, 31b, 31c, 31d, and pipework 35b connects the heating apparatuses 31a, 31b, 31c, 31d to the hot fluid tank 34. Bypass pipework 35c connects the cold fluid tank 33 to the hot fluid tank 34. Control valves 36a to 36e control the flow of fluid in the pipework 35a, 35b, 35c.
[0035] In this example, the power delivered to the heating apparatuses 31a, 31b, 31c, 31d of the electrical heating system 30 may be controlled by altering the voltage drop across the WT 21, and / or by operating an appropriate number of the electrical heating circuits within the heating apparatuses 31a, 31b, 31c, 31d.
[0036] Figure 3 schematically illustrates a further alternative electrical system 10 to that shown in Figures 1 and 2. In this example, the electrical system 10 comprises four power distribution systems 20a, 20b, 20c, 20d which each comprise a variable voltage transformer 21a, 21b, 21c, 21d and a switchgear 22a, 22b, 22c, 22d. The each of the power distribution systems 20a, 20b, 20c, 20d are the same as the power distribution system 20 described above with reference to Figure 1.
[0037] The electrical heating system 30 is the same as described above with reference to Figure 2. In this example, the electrically powered heating circuits of the first heating apparatus 31a are connected to the switches in the switchgear 22a of the first power distribution system 20a so that each electrically powered heating circuit of the first heating apparatus 31a is operable independently of each other electrically powered heating circuit of the first heating apparatus 31a. Similarly, the electrically powered heating circuits of the second, third and fourth heating apparatuses 31b, 31c, 31d are connected to the switches in the switchgears 22b, 22c, 22d of the second, third and fourth power distribution systems 20b, 20c, 20d respectively so that each electrically powered heating circuit of the second, third and fourth heating apparatuses 31b, 31c, 31d are operable independently of each other.
[0038] In this example, the power delivered to the heating apparatuses 31a, 31b, 31c, 31d of the electrical heating system 30 may be individually controlled by altering the voltage drop across the WT 21a, 21b, 21c, 21d of the power distribution systems 20a, 20b, 20c, 20d to which the heating apparatus 31a, 31b, 31c, 31d is connected, and / or by operating an appropriate number of the electrical heating circuits, controlled by operation of the appropriate switchgear 22a, 22b, 22c, 22d, within the heating apparatuses 31a, 31b, 31c, 31d themselves.
[0039] In the examples of both Figure 2 and Figure 3 in some circumstances it may be desirable to completely shut-down one of the heating apparatuses 31a, 31b, 31c, 31d by opening all of the switches of the respective switchgear to which the heating apparatus 31a, 31b, 31c, 31d is connected. Alternatively, the switches in switchgears 22a, 22b, 22c, 22d may be operated so that not all of the electrical heating circuits of each heating apparatus 31a, 31b, 31c, 31d are operational. For example, two of the four electrical heating circuits may be operable in each of the heating apparatuses 31a, 31b, 31c, 31d. In some cases, the number of electrical heating circuits operating at any one time may differ between the heating apparatuses 31a, 31b, 31c, 31d in dependence on operational requirements .
[0040] Although not shown in Figure 1, 2 or 3, it will be understood that fluid may be delivered to, or drawn from the electrical heating system 30 by the use of additional bypass pipework and control valves.
[0041] Figure 4 schematically illustrates a method 40 of controlling an electrical system 10. In a first step 42 the method 40 comprises receiving one or more control signals indicative of one or more operational parameters of the electrical heating system 30. In a second step 44 the method 40 comprises adjusting the voltage change ratio across one or more of the variable voltage transformers 21a, 21b, 21c, 21d of the one or more power distribution systems 20a, 20b, 20c, 20d, and / or operating one or more of the switches 28a, 28b, 28c, 28d of one or more of the switchgears 22a, 22b, 22c, 22d of the one or more power distribution systems 20a, 20b, 20c, 20d in dependence on the one or more control signals.
[0042] The method 40 may comprise operating the switches 28a, 28b, 28c, 28d of one or more of the switchgears 22a, 22b, 22c, 22d such that one or more of the electrical heating circuits 32a, 32b, 32c, 32d of one or more of the electrically powered heating apparatuses 31a, 31b, 31c, 31d are operational.
[0043] In cases where the electrical system 10 comprises a plurality of electrically powered heating apparatuses 31a, 31b, 31c, 31d the method may comprise operating the switches 28a, 28b, 28c, 28d of one or more of the switchgears 22a, 22b, 22c, 22d such that all of the electrical heating circuits 32a, 32b, 32c, 32d of one or more of the plurality of electrically powered heating apparatuses 31a, 31b, 31c, 31d are inoperative.
[0044] In cases where the electrical system 10 comprises a plurality of power distribution systems 20a, 20b, 20c, 20d, the method may comprise adjusting the voltage change ratio across one or more of the variable voltage transformers 21a, 21b, 21c, 21d of the one or more power distribution systems 20a, 20b, 20c, 20d such that at least one of the variable voltage transformers 21a, 21b, 21c, 21d has a different voltage change ratio to at least one other variable voltage transformer. A control system 50 for controlling an electrical system 10 is schematically illustrated in Figure 5. The control system 50 comprises a processor 52 and a memory device 54. The processor 52 may be one or more electronic processing device which operably executes computer- readable instructions. The memory device 54 may be one or more memory device. The memory device 54 is electrically coupled to the processor 52 and configured to store instructions and / or data. The processor 52 is configured to access the memory device 54 to execute the instructions stored thereon, to access data stored thereon and / or to store data thereon.
[0045] The controller 50 comprises at least one input 56 and at least one output 58. The at least one input 56 may comprise an electrical input of the controller 50. The at least one output 58 may comprise an electrical output of the controller 50. The at least one input 56 is arranged to receive one or more input control signals indicative of one or more operational parameters of the electrical heating system 10, and the at least one output 58 is arranged to output one or more output control signals in dependence on the one or more input control signal. The one or more output control signals comprise an instruction to adjust the voltage change ratio across one or more of the variable voltage transformers 21a, 21b, 21c, 21d of the one or more power distribution systems 20a, 20b, 20c, 20d, and / or operate one or more of the switches 28a, 28b, 28c, 28d of one or more of the switchgears 22a, 22b, 22c, 22d of the one or more power distribution systems 20a, 20b, 20c, 20d. It will be understood that the above example electrical systems 10 are illustrative only . In particular , it is not es sential that the electrical heating circuit s be located together in discrete heating apparatus . In addition , it will be understood that any suitable number of electrical heating circuit s may be used in any suitable arrangement . The heating circuits need not be used to heat fluid , and any industrial heating application is envisaged . It will therefore be understood that the hot and cold fluid tanks are not es sential .
[0046] It will be understood that the system des cribed above may be used for any suitable heating application including the heating of all types of fluid including gases and liquid .
[0047] While many pos sible variations of the electrical system 10 have been described above , it will be clear to the s killed person that additional variations and modif ications can be made without departing f rom the scope of the invention as claimed in the appended claims .
Claims
SP3207C L A I M S1. An electrical system comprising: one or more power distribution systems, wherein the or each power distribution system comprises a variable voltage transformer having an input side and an output side, and a switchgear comprising a plurality of switches, wherein the input side of the variable voltage transformer is configured to be connected to an electrical power supply in use, and wherein the plurality of switches are connected in parallel to the output side of the variable voltage transformer; and an electrical heating system comprising a plurality of electrically powered heating circuits, wherein each electrically powered heating circuit is connected to one of the plurality of switches of the switchgear of the, or one of the, power distribution systems such that each electrically powered heating circuit is operable independently of each other electrically powered heating circuit.
2. The electrical system of claim 1, wherein the electrical heating system comprises one or more electrical heating apparatuses, wherein the or each electrical heating apparatus comprises a plurality of electrically powered heating circuits .
3. The electrical system of claim 2, wherein the or each electrical heating apparatus is connected to its own dedicated power distribution system.
4. The electrical system of claim 2 or 3, wherein the one or more electrical heating apparatuses comprise a heating vessel for heating a fluid.
5. The electrical system of claim 4, wherein the electrical heating system comprises: one or more heating vessels; a cold fluid tank; a hot fluid tank; and pipework configured to connect the cold fluid tank to the hot fluid tank via at least one heating vessel.
6. A method of controlling the electrical system of any preceding claim, the method comprising: receiving one or more control signals indicative of one or more operational parameters of the electrical heating system; and adjusting the voltage change ratio across one or more of the variable voltage transformers of the one or more power distribution systems; and / or operating one or more of the switches of one or more of the switchgears of the one or more power distribution systems , in dependence on the one or more control signals.
7. The method of claim 6, when dependent on claim 2, the method comprising operating the switches of one or more of the switchgears such that one or more of the electrical heating16 circuit s of one or more of the electrically powered heating apparatuses are operational .8 . The method of claim 7 , wherein the electrical system comprises a plurality of electrically powered heating apparatuses , the method comprising operating the switches of one or more of the switchgears such that all of the electrical heating circuits of one or more of the plurality of electrically powered heating apparatuse s are inoperative .9 . The method of claim 7 or 8 , wherein the electrical system comprises a plurality of power distribution systems , the method compris ing adj usting the voltage change ratio acros s one or more of the variable voltage trans formers of the one or more power distribution systems such that at least one of the variable voltage transformers has a dif ferent voltage change ratio to at least one other variable voltage transformer .10 . A control system for controlling the electrical system of any preceding claim, wherein the control system is configured to : receive one or more input control signal s indicative of one or more operational parameters of the electrical heating system; and transmit one or more output control signal s in dependence on the one or more input control signal s , wherein the one or more output control s ignals comprise an instruction to : adj ust the voltage change ratio acros s one or more of the variable voltage transformers of the one or more power distribution systems ; and / or- 17 - operate one or more of the switches of one or more of the switchgears of the one or more power distribution systems .