Stabilizing voltage and frequency at point of common coupling of industrial facilities
By using power electronic blocks and compensators in industrial facilities, coordinating the set points of loads and compensators, the voltage and frequency stability problems of variable energy grids during transient events are solved, and the voltage to common coupling points is achieved. and stable frequency control to ensure the continuity and stability of the system.
Patent Information
- Application Number
- CN202280095961.8
- Authority / Receiving Office
- CN · China
- Patent Type
- Applications(China)
- Current Assignee / Owner
- Filing Date
- 2022-05-13
- Publication Date
- 2024-12-20
AI Technical Summary
The variable-energy-based grid faces stability challenges due to rapid changes in voltage and frequency during transient events, especially where tight coupling leads to instability problems in the grid and industrial facilities.
By using power electronic blocks and compensators in industrial facilities, combined with load responders and compensator responders components, the voltage at common coupling points is achieved using fast data communication lines and power controllers to coordinate the set points of loads and compensators, and the voltage at common coupling points is achieved using fast data communication lines and power controllers. and stable control of frequency, providing inertial power and power balance responses to suppress voltage and frequency fluctuations.
Effectively maintain process stability in the power grid and industrial facilities, prevent voltage and frequency from exceeding the allowable limit, ensure system continuity, especially when active and reactive power changes, and reduce the impact of transient events on the power grid.
Smart Images
Figure CN119174077A_ABST
Abstract
Description
Technical Field
[0001] The invention relates to an industrial installation connected to an electrical grid. The invention also relates to a method, a computer program, a computer readable medium and a controller for stabilizing the voltage and / or frequency at a point of common coupling of an industrial installation with an electrical grid. Background Art
[0002] Grids based on variable energy sources rely on power electronics, and when their contribution is large, such grids can be referred to as power electronics dominated grids (PEDG). These grids are characterized by varying grid strength, low and varying inertia, and small short-circuit power. For example, the generation mix may be constantly changing due to the weather dependency of some variable energy sources.
[0003] Operations in these grids face both steady-state and transient stability challenges. In particular, transient events on the grid and load side can have far-reaching effects due to rapid changes in active and reactive power, affecting system voltage and frequency.
[0004] In contrast to conventional power grids, voltage and frequency in PEDGs may be tightly coupled. This tight coupling may amplify the impact of transient events, leading to voltage and frequency stability issues.
[0005] Transient events include load shedding of hydrogen production units, load shedding of arc furnaces, inrush current of high-power converter transformers, instability due to arcs, symmetrical and asymmetrical faults on the load side, symmetrical and asymmetrical faults on the grid side, load shedding, etc. During the above transient events (which include rapid changes in active and reactive power), the balance of supply and demand may be disturbed, resulting in voltage and frequency changes. In traditional strong power grids, changes in power components do not affect system voltage and frequency. However, in PEDG, such scenarios may cause large-scale industrial facilities and grid disturbances. Summary of the invention
[0006] The object of the invention is to provide a control system and a control method which allow operating an industrial installation with strong and / or dynamically changing loads in a weak grid, in particular a grid powered mainly by renewable energy sources and power electronics blocks supplying electric arc furnaces.
[0007] This object is achieved by the subject-matter of the independent claims. Further exemplary embodiments are evident from the dependent claims and the following description.
[0008] A first aspect of the present invention relates to industrial facilities connected to a power grid. Industrial facilities may include electrical loads and / or be suitable for handling medium voltages (such as voltages exceeding 6kV) and / or high currents (such as exceeding 100A). Power electrical systems and / or power electrical components of industrial facilities may be distribution networks, power electronic blocks (such as inverters, rectifiers, and converters), passive and active filters, power loads, and power supplies. Such power loads may be any electrical device that consumes electrical power, such as motors, electric arc furnaces, etc. Such power supplies may be any electrical device that provides electrical power, such as battery storage systems, fuel cells, etc.
[0009] The grid may be powered by renewable and / or variable power sources.
[0010] According to one embodiment of the present invention, an industrial facility includes a distribution network connected to a power grid at a point of common coupling. The distribution network may include one or more cables for connecting the point of common coupling to power electrical components of the industrial facility. The point of common coupling may be a point where the industrial facility interfaces with a public network or energy service provider. The point of common coupling may be a high voltage or medium voltage bus or a substation.
[0011] The distribution network can connect loads and power sources and other power electrical components to the grid. On the one hand, the voltage and / or frequency of the electric power at the point of common coupling may change due to instability in the grid. On the other hand, the voltage and / or frequency of the electric power at the point of common coupling may change due to changes in load demand of the industrial facility. Using the systems and methods described herein, the voltage and / or frequency at the point of common coupling can be stabilized by controlling the components of the industrial facility. For example, this may be beneficial when the industrial facility includes a hydrogen supply pelletizing plant (with or without an arc furnace). Without the controls and systems described herein, a weak, unstable grid may become unstable due to the operation of the pelletizing plant and / or the arc furnace, especially during transient events, until the industrial facility or at least its components must be slowed down or shut down for stability reasons.
[0012] According to one embodiment of the present invention, an industrial facility comprises at least one load connected to a power distribution network via at least one power electronic block. The load may be any electrical device that consumes electrical power. Each load may have one or more power electronic blocks. Each power electronic block is suitable for converting a current from the power distribution network into a current supplied to a corresponding load. The power electronic blocks may be natural or forced rectifier converter types. They may also be direct or indirect converter types. For example, the power electronic block may be a rectifier, an inverter or a converter. The power electronic block may include a power semiconductor switch that may be controlled to provide the functionality of the power electronic block.
[0013] According to one embodiment of the present invention, each power electronic block includes a load responder component, which is suitable for meeting and / or determining the load demand of the corresponding load. In general, the load responder component can be part of the controller of the power electronic block. The load responder component can be a module, such as a hardware or software module of the controller. The load responder determines the load demand of the load, such as the power demand of the load, which can refer to active power and / or reactive power, and / or power quality issues such as harmonics, power factor, flicker, etc. The load demand can be sent to the central controller and / or the power controller via a data communication line for further processing.
[0014] The load responder component can determine additional information, such as load state change information, such as the load will increase and / or decrease its power demand in the future. The load responder component can also determine electrical measurement information at the input of the load, such as active power and reactive power.
[0015] The load responder assembly may also receive power control information about the power distribution network, such as that the load should reduce its power demand in the future. For example, an industrial facility may receive information that a power source may be disconnected from the power grid, and therefore the industrial facility must reduce its power demand. The power control information may be received from the central controller and / or the power controller via a data communication line.
[0016] According to one embodiment of the invention, an industrial facility comprises at least one compensator connected to a power distribution network. Each compensator is suitable for stabilizing the voltage and / or frequency in the power distribution network. A compensator may be any electrical device that stabilizes the voltage and / or frequency of the power distribution network and thus also the voltage and / or frequency of the power grid. It must be noted that there may be loads that are also compensators, such as an electric motor that may operate as a generator. Compensators may include power supplies, filters, reactors, etc.
[0017] Different compensators may react to changes in the grid at different speeds. A controllable electrical filter can react faster to load changes than an energy storage system and / or a mechanical compensator. Synchronous capacitors can provide faster inertia support than an energy storage system.
[0018] According to one embodiment of the invention, each compensator comprises a compensator responder component adapted to receive a stabilization command and to apply the stabilization command to the respective compensator.
[0019] In general, the compensator responder component may be part of a controller of the compensator.The compensator responder component may be a module, such as a hardware or software module of the controller.
[0020] The stabilization command may be information about stabilizing the voltage and / or frequency in the power distribution network. For example, it may include a command to increase or decrease the voltage or to provide active or reactive power support. The stabilization command may be executed by the corresponding compensator via control of the compensator responder component. The stabilization command may be received via a data communication line from the central controller and / or the power controller.
[0021] The compensator responder component can determine additional information, such as a change of state information of the compensator, for example, that the compensator (such as an energy storage device) has been exhausted. The compensator responder component can also determine electrical measurement information, such as active power and reactive power at the input of the compensator. The electrical measurement information can be sent to the central controller and / or the power controller via a data communication line for further processing.
[0022] According to one embodiment of the present invention, an industrial facility includes a power controller that communicates data with one or more load responder components and one or more compensator responder components. All data (such as load demand, state change information and / or electrical measurement information received from the responder components) can be processed by the power controller to control the voltage and / or frequency in the power distribution network. Based on the received data, the power controller determines stability commands and / or power control information and sends them to the corresponding responder components.
[0023] This can be done by adjusting the set points of the loads and compensators, i.e., the stabilization commands and / or power control information may include set points for the respective loads and / or compensators. The set points for normal operation may be transmitted from the power controller to all load and compensator responders. The power controller also receives measurements from the distribution network. The power controller maintains a model of the distribution network, the loads and the compensators. In the event that the voltage and / or frequency of the distribution network exceeds predefined limits, the power controller adjusts the set points so that the voltage and / or frequency remain within these limits. For this purpose, measurements and / or models may be used. According to one embodiment of the invention, the power controller is adapted to receive load demands from one or more load responder components, determine stabilization commands based on the load demands, and send stabilization commands to one or more compensator responder components.
[0024] Disturbances in the power grid and industrial facilities may cause rapid changes in active and reactive power at the point of common coupling. Such rapid changes may cause voltage and frequency fluctuations, which affect the process stability of the power grid and industrial facilities. To compensate for this, the industrial facility includes a combination of controllable loads and compensators, and corresponding load responder components and compensator responder components, which are coordinated by a power controller. This configuration performs a power balancing response by injecting and / or absorbing and / or providing inertial power to maintain the voltage and frequency within allowed limits.
[0025] Inertia power can be connected to frequency and active power. When there is a disturbance, such as load suppression similar to that in a low-inertia system, the frequency may be affected momentarily due to active power mismatch. In conventional power grids, synchronous machines can provide automatic inertia support by virtue of the kinetic energy stored in their rotors. This suppresses instantaneous drops in frequency. In distribution networks that rely on power electronics, the inertia support provided by synchronous machines may be missing. In this case, the inertia support from the load side can suppress the instantaneous rise or fall in frequency due to the disturbance. Synchronous capacitors can provide automatic inertia support because they are directly connected to the distribution network. As an additional measure, other elements (such as hydrogen production units) can be increased or decreased by changing their active power consumption to provide frequency support. The first response can be made via the synchronous capacitor, and the next response can be made via the hydrogen production unit, thereby adjusting their active power consumption.
[0026] According to one embodiment of the present invention, the power controller is connected to one or more load responder components and one or more compensator responder components via a data communication line suitable for transmitting data packets in less than 25μs. Such a data communication line may be referred to as a fast data communication line or a high-speed data communication line. The data communication may be so fast that a control system including the power controller and the responder components is adapted to react to changes in voltage and / or frequency, so that direct control of instantaneous voltage in the distribution network is possible. In other words, the data communication may be so fast that a reaction may be implemented faster than the cycle of the voltage in the distribution network. In this way, the power controller may coordinate the various load responder components and compensator responder components via a high-speed point-to-point connection.
[0027] According to one embodiment of the present invention, the power controller is connected to one or more load responder assemblies and one or more compensator responder assemblies via fiber optic data communication lines. The fiber optic lines may be made of glass and are suitable for providing fast data communication as described above.
[0028] According to one embodiment of the invention, one of the at least one compensator is a controlled electrical compensator comprising at least one of a resistor, an inductor and a capacitor. An example of such a controlled compensator providing an active power compensator is a static watt compensator.
[0029] Generally speaking, controlled compensators for reactive power include synchronous capacitors, static VAR compensators, static synchronous compensators, dynamic voltage restorers, unified power flow controllers, line-to-line power flow controllers, etc.
[0030] According to one embodiment of the invention, one of the at least one compensators is a controlled mechanical compensator comprising a rotating inertial element, such as a heavy drum driven by an electric motor / generator, with or without a converter and / or power electronics block for controlling the energy flow from the power distribution grid into the drum and vice versa. Such a device may be a synchronous capacitor with or without a flywheel and / or may provide the rotating inertia.
[0031] According to one embodiment of the invention, one of the at least one compensator is a controlled energy storage system, such as a capacitor bank, a battery bank and / or a fuel cell connected to a hydrogen tank. The energy storage system may also include a converter and / or a power electronics block for controlling the energy flow from the distribution grid to the energy storage element and vice versa.
[0032] According to one embodiment of the present invention, each of the one or more power electronic blocks includes at least one of a rectifier and an inverter. In general, the power electronic blocks may be composed of power electronic components, such as diodes, thyristors and transistors, which are controlled by corresponding controllers. The controller may provide a responder component.
[0033] According to one embodiment of the invention, one of the at least one load is an arc furnace. The arc furnace may generate severe disturbances in the power distribution network and may be compensated by the control system described herein.
[0034] According to one embodiment of the present invention, one of the at least one loads includes an electrolyzer group and / or a fuel cell. The electrolyzer group can be used to convert electrical energy into chemical energy stored in a hydrogen tank. The fuel cell can convert hydrogen back into electrical energy. Such a load can also be considered a compensator.
[0035] According to one embodiment of the invention, the industrial facility may also include a hydrogen supply to the pelletizing plant, which is supplied with hydrogen from hydrogen tanks. In this way, energy surplus from the grid can be compensated by producing hydrogen, which can then be used to supply the pelletizing plant or can be used to generate electricity via fuel cells.
[0036] According to one embodiment of the present invention, the industrial facility further comprises an automation controller adapted to control the load. The automation controller may be a PLC controller (Programmable Logic Controller). The automation controller may be used to coordinate process requirements with components (such as loads) that control the process of the industrial facility. The automation controller is used as a superimposed controller. The automation controller typically contains and / or determines process information, such as set points that are used to maintain the process and to perform emergency actions related to the process via the control components.
[0037] The automation controller is in data communication with the power controller (e.g., via a data communication line), which is slower than data communication between the power controller and the responder component. For example, the automation controller can be connected to the power controller via a fieldbus. In this way, the power controller coordinates with the automation controller and the utility to provide steady state support.
[0038] According to one embodiment of the present invention, the industrial facility further includes a utility interface for receiving external data provided to the industrial facility. In addition, the utility interface can communicate data with the power controller. The utility interface can be used to receive information about the power grid, such as power supply connection and disconnection with the power grid. Such information can also be used to coordinate loads and compensators.
[0039] Another aspect of the invention relates to a method for stabilizing voltage and / or frequency at a point of common coupling of an industrial facility with a power grid. The method may be performed by a power controller together with a responder assembly and / or more generally a controller of a compensator and a load.
[0040] According to one embodiment of the present invention, the method includes: receiving a load demand from one or more load responder components. The load demand may be received via a data communication line connecting the power controller with the load. The load demand may contain information about the power demand of the corresponding load.
[0041] According to one embodiment of the invention, the method includes receiving state change information from one or more load responder components and / or from one or more compensators. The load demand may be received via a data communication line connecting the power controller with the load and the compensator. The state change information may, for example, describe that the corresponding load will increase and / or decrease its power demand in the future and / or the corresponding compensator (such as an energy storage device) is exhausted.
[0042] According to one embodiment of the invention, the method includes: receiving electrical measurement information from one or more load responder components and / or from one or more compensators. The electrical measurement information may be received via a data communication line connecting the power controller with the load and the compensator. The electrical measurement information may include voltage, current, active power, reactive power, etc. measured by the corresponding responder component and / or derived from these measurements by the corresponding responder component.
[0043] According to one embodiment of the present invention, the method includes: using a power controller to determine a stabilization command and / or power control information according to load demand, state change information and / or electrical measurement information.
[0044] Generally speaking, the goal of a power controller is to maintain the voltage and frequency within the distribution network and / or at the point of common coupling within permitted limits. These permitted limits may be provided in the power controller.
[0045] The power controller may determine compensation and / or reaction of the load and compensator to achieve this goal. Depending on the required compensation (such as encoded in the load demand) and based on the available reserves (such as encoded in the state change information from the compensator), a set point may be determined, which, for example, provides frequency support, active power and / or reactive power compensation. The stabilization command and / or power control information may include such set points. If the load demand of the load cannot be fully compensated, power control information may be determined, which, for example, notifies the load to reduce its power consumption.
[0046] According to one embodiment of the invention, the method comprises: sending a stabilization command to one or more compensator responder components and / or sending power control information to one or more load responder components. The information may be sent via a fast data communication link as described above.
[0047] According to an embodiment of the present invention, the method comprises: controlling the load and / or the compensator based on the stabilization command and / or the power control information. Such control may be performed by a controller of the corresponding load and / or the compensator.
[0048] Voltage and frequency can be considered as the main parameters of the control method performed by the power controller. The reliable operation of industrial facilities depends on whether their amplitudes are within the allowed limits. During disturbances from the power grid or one or more loads, their values may exceed the allowed limits, especially in power grids with low short-circuit power and low inertia due to changes in active power and reactive power. This may affect one or more loads, resulting in instability in the power grid and / or industrial facilities, such as from protection-related tripping. During these critical situations, the method provides fast controlled compensation of active power and reactive power to ensure system stability. The control method compensates for changes in power components and suppresses voltage and frequency changes beyond allowed limits. This allows process continuity. In particular, compensators (such as battery storage systems) and load responders (such as hydrogen production units, which include electrolyzer groups and storage devices and high-power fuel cells) can be used for controlled compensation of active power and reactive power.
[0049] Other aspects of the invention relate to a computer program, which, when executed by a processor, is adapted to perform the method as described above and below, and to a computer-readable medium in which such a computer program is stored.
[0050] For example, the method may be performed by a control system of an industrial facility, which control system may include one or more controllers, each controller including a memory and a processor. Such controllers may include a power controller, a load responder component, and / or a compensator responder component, all of which may be a controller of the industrial facility or at least a part or module of a controller.
[0051] The computer readable medium may be a hard disk, a USB (Universal Serial Bus) storage device, a RAM (Random Access Memory), a ROM (Read Only Memory), an EPROM (Erasable Programmable Read Only Memory) or a flash memory. The computer readable medium may also be a data communication network, such as the Internet, which allows downloading program code. In general, the computer readable medium may be a non-transitory or a transient medium.
[0052] Another aspect of the invention relates to a power controller adapted to perform the methods described above and as described below. The power controller may be and / or may include one or more controller components. Each controller component may include a memory and a processor. Some or all of the power components may be provided by a controller module of an industrial facility. The controller components of the power controller may be interconnected via fast data communication lines and / or optical fiber-based data communication lines.
[0053] It has to be understood that features of a power controller as described above and below may be features of an industrial device, a method, a computer program and a computer-readable medium as described above and below, and vice versa.
[0054] These and other aspects of the invention will be apparent from and elucidated with reference to the embodiments described hereinafter. BRIEF DESCRIPTION OF THE DRAWINGS
[0055] The subject matter of the invention will be explained in more detail hereinafter with reference to exemplary embodiments illustrated in the drawings.
[0056] Figure 1 An industrial installation according to an embodiment of the invention is schematically shown.
[0057] Figure 2 A flow chart showing a method for stabilizing voltage and / or frequency at a point of common coupling of an industrial facility is shown.
[0058] The reference numerals used in the figures and their meanings are listed in summary form in the list of reference numerals. In principle, identical components are provided with the same reference numerals in the figures. DETAILED DESCRIPTION
[0059] Figure 1An industrial facility 10 is shown, which is connected to a power grid 14 via a point of common coupling 12. The power grid 14 may be a power grid powered by renewable energy and / or variable power sources.
[0060] Industrial facility 10 includes a power distribution network 16 including power lines 18. Distribution network 16 is connected to power grid 14 at a point of common coupling 12. Distribution network 16 may include one or more power lines 18, such as cables, for connecting point of common coupling 12 to power electrical components of industrial facility 10. Connections may be made to busbars of distribution network 16 via switchgear or circuit breakers.
[0061] The industrial facility 10 also includes loads 20, 20a, 20b, which are connected to the power distribution network 16 via a power electronics block 22. In general, a load can be any electrical device that consumes power. The load 20a is an arc furnace. The arc furnace 20a may generate severe disturbances in the power distribution network 16 and can be compensated for by the methods and control systems described herein.
[0062] The load 20b includes an electrolyzer group and / or a fuel cell, which is connected to a hydrogen tank 26 via a pipe 24. The electrolyzer group can be used to convert electrical energy into chemical energy stored in the hydrogen tank 26. The chemical energy of hydrogen can be converted back into electrical energy through a fuel cell.
[0063] The industrial facility 10 may also include a hydrogen supply pelletizing plant 28 , which is supplied with hydrogen from a hydrogen tank 26 , for example via a further pipeline 24 .
[0064] Each power electronic block 22 is connected to a corresponding load 20 via a power line 18. Each power electronic block 22 is adapted to convert current from the power distribution network 16 into current supplied to the corresponding load 20. The power electronic block 22 may include a rectifier, an inverter and / or a converter. In general, the power electronic block 22 may include power electronic components, such as diodes, thyristors and transistors, which are controlled by a corresponding controller. The power electronic block 22 may include a power semiconductor switch, which may be controlled to provide the functionality of the power electronic block 22.
[0065] Furthermore, the industrial facility 10 comprises compensators 30 connected to the power distribution network 16. Each compensator 30 is adapted to stabilize the voltage and / or frequency in the power distribution network 16. In general, the compensator 30 may be any electrical device that stabilizes the voltage and / or frequency of the power distribution network 16 and, therefore, also the voltage and / or frequency of the power grid 14. It must be noted that there may be loads 20, such as load 20b, which may also be considered as compensators 30.
[0066] The compensator 30a is a controlled energy storage system, such as a capacitor bank or a battery bank. The energy storage system 30a may also include a converter and / or power electronics blocks for controlling the energy flow from the power distribution grid 16 to the energy storage element and vice versa.
[0067] The compensator 30b is a controlled mechanical compensator comprising a rotating inertia element, such as a heavy drum driven by a motor / generator, and a converter and / or power electronics block for controlling the energy flow from the power distribution grid 16 into the drum and vice versa. The compensator 30b may also be a synchronous capacitor with or without a flywheel and / or may provide rotating inertia.
[0068] The compensator 30c is a controlled electrical compensator comprising at least one of a resistor, an inductor and a capacitor. An example of such a controlled compensator 30c providing an active power compensator is a static watt compensator.
[0069] Generally speaking, the controlled compensator 30 of reactive power includes a synchronous capacitor, a static VAR compensator, a static synchronous compensator, a dynamic voltage restorer, a unified power flow controller, an inter-line power flow controller, and the like.
[0070] Each power electronics block 22 and compensator 30 includes a responder component 32, 34. The responder component 32, 34 may be part of a controller of the respective power electronics block 22 or the respective compensator 30. The responder component 32, 34 may be a module, such as a hardware or software module of such a controller. The compensator 30 has a compensator responder component 32. The power electronics block 22 has a load responder component 34.
[0071] The load responder components 32, 34 are in data communication with a power controller 36 of the industrial facility 10. The power controller 36 is responsible for controlling the real and reactive power provided by the loads 20 and compensators 30 to the distribution network 16 and / or maintaining the voltage and frequency of the distribution network 16 within limits.
[0072] The power controller 36 is connected to the responders 32, 34 via a data communication line 38, which is suitable for transmitting data packets in less than 25 μs. For example, the protocol used can be a power link. The data communication line 38 can be a fiber optic data communication line. In this way, the data communication is also not disturbed by electromagnetic fields generated in industrial facilities (such as the electromagnetic fields generated by the power electronics block 22).
[0073] The industrial facility 10 also includes an automation controller 40 adapted to control a process performed by the load 20. The automation controller 40 communicates data with the power controller 36 via a data communication line 42, which is slower than the data communication via the communication line 38. For example, the automation controller 40 may be connected to the power controller 36 via a fieldbus.
[0074] In addition, the industrial facility 10 includes a utility interface 44 for receiving external data provided to the industrial facility 10. In addition, the utility interface 44 is in data communication with the power controller 36. This data communication can be performed via the data communication line 38, as described above. The utility interface 44 can be used to receive information about the power grid, such as the connection and disconnection of power sources to the power grid. Such information can also be used by the power controller 36 to coordinate the load 20 and the compensator 30. The utility interface 44 can also be in data communication with the automation controller 40, which can be performed via the data communication line 42, such as via a fieldbus, as described above.
[0075] Figure 2 A flow chart of a method for stabilizing voltage and / or frequency at a point of common coupling 12 of an industrial facility 10 with a grid 14 is shown. The method is performed by a power controller 36 and responder components 32, 34 and / or more generally by controllers of load 20 and compensator 30.
[0076] In step S10, a load demand 50 is received from the load responder component 34. The load demand 50 may contain information about the power demand of the corresponding load 20.
[0077] In step S12, state change information 52 is received from the load responder component 34 and / or from the compensator responder component 32. For example, the state change information 52 may describe that the corresponding load 20 will increase and / or decrease its power demand in the future and / or trip due to protection-related reasons and / or the corresponding compensator 30 (such as an energy storage device) is exhausted.
[0078] In step S14, electrical measurement information 54 is received from the load responder component 34 and / or the compensator responder component 32. The electrical measurement information 54 may include voltage, current, active power, reactive power, etc. measured by the respective responder component and / or derived from these measurements by the respective responder component 32, 34.
[0079] The load demand 50 , the state change information 52 , and the electrical measurement information 54 are transmitted to the power controller 36 via the data communication line 38 .
[0080] In step S16, the power controller 36 determines a stabilization command 56 and / or power control information 58 based on the load demand 50, the state change information 52, and / or the electrical measurement information 54. Generally speaking, the goal of the power controller 36 is to maintain the voltage and frequency within the power distribution network 16 and / or at the point of common coupling 12 within permitted limits. These permitted limits may be provided in the power controller 36.
[0081] The power controller 36 determines the compensation and / or reaction of the load 20 and the compensator 30 to achieve this goal. Depending on the required compensation (such as encoded in the load demand 50) and based on the available reserves (such as encoded in the state change information 52 from the compensator 30), a set point can be determined, which provides, for example, inertial response, active power and / or reactive power compensation. Due to the rotating mass of the synchronous capacitors, the inertial response from the synchronous capacitors may be automatic. The inertial response from other compensators (such as electrolyzers or battery storage systems) may have to be controlled by the set point. The stability command 56 and / or the power control information 58 may include such a set point. If the load demand 50 of the load 20 cannot be fully compensated, the power control information 58 can be determined, which notifies the load 20 to reduce its power consumption.
[0082] The stabilization command 56 may be information about stabilizing the voltage and / or frequency in the power distribution network 16. For example, it may include a command to increase or decrease the voltage or provide active or reactive power support. The stabilization command 56 may be executed by the corresponding compensator 30 via the control of the compensator responder component 32. In step S18, the power controller 36 sends the stabilization command 56 to the compensator responder component 32 and sends the power control information 58 to the load responder component 34. The information is sent via the data communication line 38.
[0083] In step S20, the compensator responder component 32 applies the stabilization command 56 to the corresponding compensator 30. The load responder component 34 applies the power control information 58 to the power electronics block 22 and the load 20.
[0084] The power electronics block 22, the load 20, and / or the compensator 30 are controlled based on the stabilization command 56 and / or the power control information 58. Such control may be performed by controllers of the respective loads and / or compensators.
[0085] During normal operating conditions, the automation controller 40 may communicate set points to the various load responder components 34 via the power controller 36. Based on information exchange with the load and compensator responder components 32, 34 and information from measurements about the distribution network 16, the power controller 36 further adjusts and / or transmits set points to the load and compensator responder components 32, 34 to maintain the voltage and frequency in the distribution network 16 within permitted limits. The automation controller 40 may also provide information to the power controller 36 regarding load forecasts or weather-related power generation forecasts, which may be used to further adjust the set points of the loads 20 and compensators 30.
[0086] During unexpected conditions, such as load shedding, the utility interface 44 may communicate directly with the power controller 36, which may control the load 20 by overriding the setpoints from the automation controller 40 and / or may send the setpoints directly to the load and compensator responder components 32, 34. In another example, when load shedding occurs due to process or electrical system related reasons, the power controller 36 receives this information from the corresponding load responder component 34 or directly interprets this information based on measurements.
[0087] Based on the available information, the power controller 36 can send a stabilization command 56 to the compensator responder component 32, taking into account the amount of compensation required to maintain the voltage and frequency. When the compensation reserve has been reached, the power controller 36 sends a power control message 58 to the load 20 (such as a hydrogen unit) to increase or decrease its production or obtain support from a battery storage system. Through this combined action, the power controller 36 can place the voltage and frequency within allowed limits to allow process continuity. In another example, when there is a grid fault, the power controller 36 can initiate voltage support to the distribution network 16 by changing the set points for the compensator 30 and the load 20.
[0088] In this way, voltage and frequency stability at the point of common coupling 12 can be achieved by using a controlled load 20 and a compensator 30. Depending on the scenario (i.e., voltage or frequency support or both), the combination provides inertial response, reactive power support, and / or active power support. Inertial support can be automatically provided using a combination of synchronous capacitors and a flywheel. By using a hydrogen production unit and / or a battery storage system, controlled inertial support can be provided.
[0089] Although the present invention has been described in detail and in the drawings and the foregoing description, these descriptions and descriptions should be regarded as illustrative or exemplary rather than restrictive; the present invention is not limited to the disclosed embodiments. Those skilled in the art can understand and implement other variations of the disclosed embodiments and practice the claimed invention by studying the drawings, the disclosure and the appended claims. In the claims, the word "comprising" does not exclude other elements or steps, and the indefinite article "one" or "an" does not exclude a plurality. A single processor or controller or other unit may implement the functions of several items stated in a claim. The fact that certain measures are stated in mutually different dependent claims does not in itself indicate that a combination of these measures cannot be fully utilized. Any figure marks in the claims should not be interpreted as limiting the scope.
[0090] Reference numerals list
[0091] 10Industrial Facilities
[0092] 12 Common coupling point
[0093] 14 Power grid
[0094] 16Distribution network
[0095] 18 Power Lines
[0096] 20 load
[0097] 20a AC or DC electric arc furnace
[0098] 20b Electrolyzer stack and / or fuel cell
[0099] 22 Power Electronic Blocks
[0100] 24 Pipeline
[0101] 26 Hydrogen tanks
[0102] 28 Pelletizing Plant
[0103] 30 compensator
[0104] 30a Energy storage system
[0105] 30b Mechanical compensator
[0106] 30c Electrical compensator
[0107] 32 Compensator Responder Components
[0108] 34 Load Responder Components
[0109] 36 Power Controller
[0110] 38 data communication lines
[0111] 40 Automation Controller
[0112] 42 data communication lines
[0113] 44 Utility Interface
[0114] 50 Load Requirement
[0115] 52 Status change information
[0116] 54 Electrical measurement information
[0117] 56 Stability Command
[0118] 58 Power control information
Claims
1. An industrial facility (10) connected to an electric grid (14), the industrial facility (10) comprising: a power distribution network (16) connected to the power grid (14) at a point of common coupling (12); at least one load (20) connected to the power distribution network (16) via at least one power electronic block (22), each power electronic block (22) being adapted to convert current from the power distribution network (16) into current supplied to the respective load (20), and each power electronic block (22) comprising a load responder component (34) adapted to determine a load demand (50) of the respective load (20); at least one compensator (30) connected to the power distribution network (16), each compensator (30) being adapted to stabilize a voltage and / or a frequency of a current in the power distribution network (16), and each compensator (30) comprising a compensator responder component (32) adapted to receive a stabilization command (56) and to apply the stabilization command (56) to the corresponding compensator (30); A power controller (36) is in data communication with one or more load responder components (34) and one or more compensator responder components (32), and the power controller (36) is suitable for: receiving a load demand (50) from the one or more load responder components (34), determining a stabilization command (56) based on the load demand (50) and sending the stabilization command (56) to the one or more compensator responder components (32).
2. The industrial facility (10) according to claim 1, The power controller (36) is connected to the one or more load responder components (34) and the one or more compensator responder components (32) via a data communication line (38), wherein the data communication line (38) is suitable for transmitting a data packet in less than 25 μs.
3. The industrial facility (10) according to claim 1 or 2, The power controller (36) is connected to the one or more load responder assemblies (34) and the one or more compensator responder assemblies (32) via a fiber optic data communication line (38).
4. The industrial plant (10) according to one of the preceding claims, One of the at least one compensator (30) is a controlled electric compensator (30c) comprising at least one of a resistor, an inductor and a capacitor.
5. The industrial plant (10) according to one of the preceding claims, One of the at least one compensator (30) is a controlled mechanical compensator (30b), the controlled mechanical compensator (30b) comprising a rotating inertia element.
6. The industrial plant (10) according to one of the preceding claims, One of the at least one compensators (30) is a controlled energy storage system (30a).
7. The industrial plant (10) according to one of the preceding claims, The power electronics block (22) includes at least one of a rectifier and an inverter.
8. The industrial plant (10) according to one of the preceding claims, One of the at least one load (20a) is an electric arc furnace.
9. The industrial facility according to claim 1, One of the at least one load (20b) comprises an electrolyzer group and / or a fuel cell.
10. The industrial facility (10) according to one of the preceding claims, further comprising: an automated controller (40) adapted to control the load (20); The automation controller (40) is in data communication with the power controller (36).
11. The industrial facility (10) according to one of the preceding claims, further comprising: a utility interface (44) for receiving external data provided to the industrial facility (10); The utility interface (44) is in data communication with the power controller (36).
12. A method for stabilizing the voltage and / or frequency at a point of common coupling (12) of an industrial installation (10) and a power grid (14) according to one of the preceding claims, the method comprising: receiving, with the power controller (36), a load demand (50) from the one or more load responder components (34); determining a stabilization command (56) based on the load demand (50) using the power controller (36); The stabilization command (56) is sent to the one or more compensator responder components (32).
13. A computer program adapted to perform the method according to claim 12 when executed by a processor.
14. A computer readable medium in which the computer program according to claim 13 is stored.
15. A power controller (36) adapted to perform the method according to claim 12.