Current transformer and method for controlling it

Abstract

Power supply system, comprising: at least one conductor with a first end and a second end; a phasor measurement unit (PMU) connected to the first end of the conductor, wherein the PMU is configured to acquire phasor data at the first end and to generate a phasor signal containing the phasor data; a power generation system connected to the second end of the conductor and configured to supply current to the conductor, wherein the power generation system comprises a power source, a current transformer and a control unit, wherein the control unit is connected to the PMU via communication technology and is configured to receive the phasor signal and to control the current transformer at least partially based on the phasor data; and a measuring device that is connected to the converter control via communication technology and is configured for this purpose: to measure at least one voltage and current flow at the second end of the second conductor; and to generate an output current signal that contains converter output data representing at least one of the voltage and current flow measured at the second end of the conductor; wherein the converter control is further configured to determine an impedance (x) of the conductor based on the converter output data and the phasor data; the converter control is designed to determine, at least partially, the maximum current that the network can accept based on the impedance of the conductor.

Description

Background of the invention

[0001] The embodiments described herein relate essentially to the operation of a power generation system and, in particular, to the use of data obtained from a phase position or so-called phasor measuring unit (PMU) to control the power generation system.

[0002] Solar and wind power are examples of renewable energy sources that are becoming increasingly attractive alternative energy sources. Solar energy, in the form of sunlight, can be converted into electrical energy by solar cells. A more general term for devices that convert light directly into electrical energy is "photovoltaic cells." Solar farms contain multiple interconnected solar cells to provide a desired amount of electricity. Wind energy can be converted into electrical energy using a wind turbine generator. Wind turbine generators typically contain a rotor with multiple blades that convert wind energy into the rotary motion of a drive shaft, which in turn is used to drive an electric generator. Wind farms contain multiple interconnected wind turbine generators to provide a desired amount of electricity.

[0003] Electricity generated by a power plant using renewable or fossil fuel energy sources is typically delivered to a consumer via an electrical grid. The generated electricity may be fed to power electronics, such as a current transformer, to condition it before it is fed into the grid. Electricity fed into the grid must meet grid connection requirements. These requirements address safety and power quality concerns. For example, grid connection requirements include the operation of the power generation system during a transient grid event, such as a short circuit in the electrical grid. This capability may be referred to as low-voltage ride-through (LVRT) or zero-voltage ride-through (ZVRT).An LVRT / ZVRT event is a condition in which the alternating current (AC) supply voltage is low on one or more phases of the electrical grid. During an LVRT / ZVRT event, the grid's ability to accept power from the generating system is reduced. Another grid connection requirement is that the generating system's output parameters must match the voltage and frequency of the electricity flowing through the grid.

[0004] The remote location and high power ratings of typical renewable energy farms typically result in poor grid connectivity unless significant investment is made to improve it, such as by incorporating larger transmission lines and / or circuit compensation equipment. A low short-circuit ratio (SCR) indicates a weak grid connection. For example, if the SCR is below 1.5, a conventional current-controlled generator may not be able to operate stably, and a voltage-controlled generator will need to be tuned relatively slowly to operate stably. Operating the generator at the slower tuning rate requires additional equipment investment to ensure sufficient operational reserve (i.e., increasing the size of a DC bridge capacitor included in the current transformer).

[0005] Furthermore, renewable energy farms typically include high-power electric generators to enable the farm to withstand a fault event and avoid load shedding or a post-fault outage. However, during a voltage dip, and especially a zero-voltage fault event, maintaining synchronization with the grid voltage is difficult because the measured grid reference voltage, typically used to maintain synchronization between the electric generator and the grid, is low. If a fault event is severe, there may not be enough residual grid voltage available for the control system to use as a reference. Under these circumstances, the generator control system may independently determine a frequency at which to deliver current, which may be out of sync with the grid.If the generators are out of sync with the grid during recovery from a fault event, a harmfully high transition current flow can occur due to a phase angle difference between the generators and the grid.

[0006] US patent 2009 / 0079267A1 discloses a current transformer control unit for controlling a current transformer with a device for determining phasor data.

[0007] EP 2 478 610 B1 discloses a voltage converter designed as a Static Synchronous Compensator (STATCOM). BRIEF DESCRIPTION OF THE INVENTION

[0008] In one aspect, a power supply system is provided. The power supply system includes at least one conductor with a first end and a second end, and a phasor measuring unit (PMU) connected to the first end of the conductor. The PMU is configured to acquire phasor data at the first end and to generate a phasor signal containing the phasor data. The power supply system also includes a power generation system connected to the second end of the conductor and configured to supply current to the conductor. The power generation system includes a power source, a current transformer, and a control unit. The control unit is communicatively connected to the PMU and is configured to receive the phasor signal and to control the current transformer, at least partially, based on the phasor data.

[0009] In a further aspect, a method for controlling at least one current transformer is provided, which is configured to supply current to an electrical network via a transmission line. The method includes monitoring the voltage output of the current transformer and recording voltage output data associated with the voltage output. The method also includes receiving a time reference signal and assigning a timestamp to the voltage output data. Furthermore, the method includes measuring a voltage phasor at a first point located at the opposite end of the transmission line from the current transformer. The method also includes receiving the time reference signal and assigning the time reference signal to the voltage phasor to generate phasor data.The procedure also includes the transmission of the phasor data to a current transformer controller and the control, using the current transformer controller, of the current transformer at least partially on the basis of the phasor data and the voltage output data.

[0010] In yet another aspect, a control system is provided for controlling a current transformer connected to a transmission line. The current transformer control system includes a GPS (Global Positioning System) receiver configured to receive a time reference signal and a memory unit configured to store the voltage output data associated with the current transformer's output. The current transformer control system also includes a processing unit configured to assign a time reference value to the output data stored in the memory unit. The processing unit is also configured to receive phasor data from a phasor measurement unit (PMU) located at the opposite end of the transmission line from the current transformer. The phasor data includes a time reference stamp that links the phasor data to a corresponding measurement time.The processing device is also designed to compare the phasor data and the voltage output data with the same timestamp and to control the operation of the current transformer at least partially on the basis of the phasor data and the voltage output data. BRIEF DESCRIPTION OF THE DRAWINGS Fig. Figure 1 is a block diagram of an exemplary power supply system that includes a power generation system connected to an electrical grid. Fig. 2 is a flowchart of an exemplary procedure for controlling the in Fig. 1 depicted power generation system. DETAILED DESCRIPTION OF THE INVENTION

[0011] The methods, systems, and computer-readable media described herein enable the control of a renewable energy-based power generation system using data collected by a phasor measurement unit (PMU). Specifically, phasor data received from a remotely located PMU is used by a power generation system controller to maintain synchronization between the power generation system and the electrical grid. Synchronization is maintained whenever the power generation system experiences a grid event or supplies power to an electrical grid with a prolonged voltage dip. Furthermore, the operation of the power generation system is based on power flow system information from the remotely located PMU. For example, converter operating parameters can be adjusted based on power flow system information.The methods, systems and computer-readable media described herein also enable the determination of the actual impedance of the electrical network and the control of the output current of the current transformer system based on the current network voltage.

[0012] Technical effects of the methods and systems described herein include at least one of: (a) monitoring a voltage output of at least one current transformer; (b) recording voltage output data associated with the voltage output of the current transformer; (c) receiving a time reference signal and assigning a timestamp to the voltage output data; (d) measuring a voltage phasor at a first point, the first point being located at the opposite end of a transmission line from the current transformer; (e) receiving the time reference signal and assigning the time reference signal to the voltage phasor to generate phasor data; (f) transmitting the phasor data to a current transformer controller; and (g) controlling the current transformer, using the current transformer controller, based at least partially on the phasor data and the voltage output data.

[0013] Fig. Figure 1 is a block diagram of an exemplary power supply system 10, comprising at least one renewable energy-based power generation system connected to an electrical grid 14 via at least one conductor 16. In the illustrative embodiment, the at least one conductor 16 includes at least one transmission line capable of providing an electrical connection to a power generation system located at a considerable distance from the electrical grid 14. Wind farms and solar farms, which generate high power output, typically require a significant amount of available space. Available space and locations with a high degree of wind / solar exposure can be hundreds of miles from load centers connected to the electrical grid 14.Although described only as a transmission line, the at least one conductor 16 may include at least one distribution line or any other conductor or group of conductors capable of connecting the power generation system to the electrical network 14. Furthermore, the power supply system 10 may include a transmission system, a distribution system, and / or any other type of system that enables the delivery of power to an electrical network.

[0014] In the illustrative embodiment, a source side 18 of the transmission line 16 contains a first power generation system 20 and a second power generation system 22. Although described as containing two power generation systems, the source side 18 of the transmission line 16 can contain any number of power generation systems that enable the power generation system 10 to function as described herein. Furthermore, if the first and second power generation systems 20 and 22 are wind-based power generation systems, the power source 18 can be referred to as a wind farm. Furthermore, if the first and second power generation systems 20 and 22 are solar-based power generation systems, the power source 18 can be referred to as a solar farm.

[0015] In the illustrative embodiment, the first power generation system 20 includes a power source 26 and a current transformer 28. The second power generation system 22 includes a power source 30 and a current transformer 32. For example, if the source side 18 is a wind farm, the power source 26 may contain a wind turbine. The current transformer 28 may include an AC / DC converter and a DC / AC converter for converting a variable-frequency power output from a wind turbine into a fixed-frequency power output. In another example, if the source side 18 is a solar farm, the power source 26 may contain a photovoltaic (PV) system, and the current transformer 28 may include a solar inverter. PVs typically output a direct current (DC) voltage.The solar converter can include an inverter that receives the DC voltage and converts it into a three-phase AC output voltage, which is applied to a load, for example, the electrical grid 14. Although it is described as a solar farm or wind farm, the power source 26 can be any type of power source connected via a converter.

[0016] As described herein, the electrical network 14 is a network of conductors and devices designed for the distribution and / or transmission of electricity. In the illustrative embodiment, the source side 18 also includes a central control unit 36. The control unit 36 ​​is connected by communication to the first power generation and conversion system 20 and the second power generation and conversion system 22. In the illustrative embodiment, the central control unit 36 ​​provides control signals to the current transformers 28 and 32, which control the output of current from systems 20 and 22, respectively. The control unit 36 ​​is a centralized controller that coordinates the operation of systems 20 and 22 to deliver a desired current to the transmission line 16.For example, the system controller 36 can be included in a wind farm management system and configured to coordinate the operation of the wind turbines and current transformers contained in the wind farm. In an alternative embodiment, the system 20 can include a transformer controller 40, and the system 22 can include a transformer controller 42. The transformer controller 40 controls the operation of the current transformer 28 and / or the power source 26 either autonomously or based on control signals received from the central system controller 36. The transformer controller 42 controls the operation of the current transformer 32 and / or the power source 26. or the power source 30 either autonomously or on the basis of control signals received from the central system control 36.

[0017] In the illustrative embodiment, the controllers 36, 40 and 42 include a processor, for example the processors 44, 46 and 48 respectively. The term "processor" as used herein refers to central processing units, microprocessors, microcontrollers, reduced instruction set (RISC) circuits, application-specific integrated circuits (ASIC), logic circuits and any other circuits or a processor capable of performing the functions described herein.

[0018] In the illustrative embodiment, the power supply system 10 also includes a phasor measurement unit (PMU) 50. In this embodiment, the PMU 50 is positioned on a network side 52 of the transmission line 16, which is located away from the source side 18. The PMU 50 measures the voltage and current flow at the network side 52 and outputs a phasor signal of the measured voltage and current flow of the network. In this illustrative embodiment, the PMU 50 is communicatively connected to the system controller 36. In an alternative embodiment, the PMU 50 is communicatively connected to the converter controllers 40 and 42. The PMU 50 can be connected to any combination of controllers 36, 40, and 42 that enables the system 10 to function as described herein.

[0019] For example, the PMU 50 can be connected to the system controller 36 via a fiber optic cable and / or any other type of wired connection that enables a function of the system 10 as described herein. In an alternative embodiment, the PMU 50 can be connected to the system controller 36 via a wireless connection. The wireless transmission may, but is not limited to, cellular transmission, satellite transmission, radio frequency (RF) transmission, transmission using an IEEE 802.11 standard (e.g., 802.11(g) or 802.11(n)), transmission using a "Microwave Access" (WiMAX) standard, and / or any wireless transmission that enables a function of the PMU 50 as described herein.

[0020] In the illustrative embodiment, the PMU 50 includes or is connected to a first GPS receiver 60, which is configured to receive time information, for example, from a satellite 62. The GPS receiver 60 can receive a signal corresponding to Coordinated Universal Time (UTC). This time information can be referred to as a "timestamp." The first GPS receiver 60 is connected to or contained within the PMU 50. A timestamp is collected, stored, and / or transmitted with a corresponding piece of information. For example, a timestamp can be stored with phasor information to record the point in time at which the phasor information was collected. The timestamp can also be sent with the corresponding phasor information to the control unit 36 ​​for use by the control unit 36.In the illustrative embodiment, the control system contains 36 time-stamped voltage phasor values. Determining the temporal information from a GPS signal enables the acquisition of coordinated timestamps at different locations.

[0021] In the illustrative embodiment, the control unit 36 ​​contains or is connected to a second GPS receiver 64. The second GPS receiver 64 is configured to receive the GPS signal 66, which contains location and time information, for example, from the satellite 62. In an alternative embodiment, the converter controllers 40 and 42 also contain GPS receivers.

[0022] In the illustrative embodiment, phasor data received from a remote PMU 50 by a control unit 36 ​​enables systems 20 and 22 to maintain synchronization with the grid 14 even during voltage dip fault events and / or zero-voltage fault events. Maintaining synchronization with the grid 14 facilitates keeping systems 20 and 22 online (i.e., running) for a certain period during grid fault events. The ability to run through a grid fault event may be included in grid integration requirements stipulated by a grid operator. The control unit 36 ​​is able to synchronize with the grid 14 using phasor data from the PMU 50 even when a grid event is sufficiently severe that the control unit 36 ​​cannot obtain a residual reference grid voltage.When the fault is rectified and the connection between systems 20 and 22 and network 14 is restored, the power output of systems 20 and 22 to network 14 is synchronized, which prevents the generation of a harmfully large current flow due to the large phase angle difference between the two sides.

[0023] Furthermore, in the illustrative embodiment, the reception of data from the remote PMU 50 enables the controller 36 to mitigate dynamic processes triggered by a sudden phase shift. For example, when a large capacitor bank connected to the grid 14 is switched on or off, or when a load is connected to or disconnected from the grid 14, the voltage phase angle on the grid side 52 can jump and lead to a large dynamic process between the current output of systems 20 and 22 and the grid 14 (e.g., a large power oscillation). Phasor data received from the PMU 50 is supplied to the system controller 36 as a forward input signal, and the system controller 36 controls the phase angle of the voltage output by systems 20 and / or 22 to limit the effect and ensure a smoother current output.

[0024] In the illustrative embodiment, the system 10 includes at least one measuring device 70, which is connected to or contained within the system controller 36 and is configured to provide voltage and / or current flow measurements from an output 72 of the systems 20 and 22. The measuring device 70 can provide measured values ​​to the system controller 36, from which the current output of the systems 20 and 22 can be determined. In the illustrative embodiment, the system controller 36 combines data from the remotely located PMU 50 (e.g., phasor data) and local measured values ​​from the measuring device 70 to determine a line impedance of the transmission line 16. In particular, the system controller 36 determines the line impedance based on the current output of the source side 18, the magnitude and phase angle of a voltage output by the source side 18, and the magnitude and phase angle of a voltage at the network side 52.Furthermore, the control unit 36 ​​can determine whether a thermal limit of a transmission line 16 has already been reached by comparing the line impedance with the temperature of the transmission line 16 (i.e., the line impedance increases proportionally to its temperature). The control unit 36 ​​can also identify a high-impedance fault on the transmission line 16, which is observed by the control unit 36 ​​as a sudden change in the line impedance.

[0025] The control unit 36 ​​can determine the line impedance based on the following formula: P≈(v1∗v2x)sin(α1−α2)

[0026] The power supplied to transmission line 90 is represented as P in Formula 1. As described above, the controller 36 determines the power P based on measured values ​​received from the measuring device 70. Furthermore, a voltage level supplied to transmission line 16 is represented as v1 in Formula 1, and a phase angle of the voltage supplied to transmission line 16 is represented as α1. In the illustrative embodiment, v1 and α1 are supplied to the controller 36 by the measuring device 70. A voltage level at the network side 52 of transmission line 16 is represented as v2 in Formula 1, and a phase angle of the voltage at the network side of transmission line 16 is represented as α2. v2 and α2 are supplied to the controller 36 by the PMU 50. The remaining variable x is the line impedance of transmission line 16.

[0027] Furthermore, once the line impedance is known, the controller can determine a maximum current value that the grid can accept. In the case of a wind farm (i.e., the power source 26 is a wind turbine), if the current transmission capacity of the grid connection is reduced to a value lower than the available wind power (i.e., due to a fault-induced voltage dip event), the converter 28 will attempt to match its current output to the wind power by continuously increasing its voltage phase lead relative to the grid. This increase in voltage phase can eventually lead to instability, similar to the "off-clock" operation of a conventional synchronous generator. Receiving phasor data from the remotely located PMU 50 can help ensure system angle stability.Under certain system events, such as a prolonged dip in grid voltage, the farm generator may encounter an angle stability problem as it attempts to push more current through the transmission line than the grid is capable of handling. Knowing the current grid voltage allows the farm control system to adaptively limit its output current and prevent such an angle stability problem.

[0028] Fig. Figure 2 is a flowchart 100 of an exemplary procedure 110 for controlling at least one current transformer, for example the (in Fig. 1 shown) current transformer 28 and / or 32. In particular, the flowchart 100 illustrates an exemplary method 110 for controlling a current output from power generation systems 20 and / or 22 at least partially on the basis of from a PMU, for example the (in Fig. 1 shown) PMU 50, received phasor data. In an example implementation, method 110 is a computer-implemented method, for example, one by a (in Fig. 1. The computer-implemented procedure is executed by the control unit 36 ​​(as shown). In another example implementation, a computer program embodied on a computer-readable medium contains at least one code segment which, when executed by a computer, such as the control unit 36, performs the procedure 110.

[0029] As described above, the current transformers 28 and 32 supply current to an electrical network, for example the (in Fig. 1 shown) electrical network 14 via a transmission line, for example the (in Fig. 1 shown) transmission line 16. Furthermore, the transmission line 16 contains a first end, for example a (in Fig. 1. Source page 18 (shown) and a second end, for example at the (in Fig. (1 shown) web page 52.

[0030] In the exemplary embodiment, method 110 includes monitoring 120 of a voltage output of at least one current transformer, for example, current transformer 28 and / or current transformer 32. For example, a measuring device, for example the (in Fig. 1. Measuring device 70 (shown) monitors the voltage output of the current transformers 28 and / or 32, 120.

[0031] In the example embodiment, the method 110 can also include a recording, 122, of voltage output data in conjunction with the voltage output of the current transformers 28 and / or 32. The method 110 can also include the reception 124 of a global time reference signal and the assignment of a timestamp to the voltage output data. The (in Fig. 1 (shown) Control Panel 36 can connect a GPS receiver, for example the (in Fig. 1 shown) GPS receiver 64 included, which is set up to receive a GPS signal, 124, which contains time reference data.

[0032] In the example embodiment, method 110 also includes the measurement 126 of a voltage phasor at a first location, for example at the network side 52 of the transmission line 16. A PMU, for example the (in Fig. The PMU 50 (as shown in Figure 1) can be positioned on the network side 52 to measure a voltage phasor on the network side 52 of the transmission line 16, 126. The procedure 110 also includes receiving 128 the time reference signal and assigning the time reference signal to the voltage phasor to generate time-stamped phasor data. In the example embodiment, the procedure 110 also includes sending 130 the phasor data to a current transformer controller, such as the controller 36.

[0033] For example, the PMU 50 can send the phasor data to the central controller 36, 130. In an alternative embodiment, 130, the PMU 50 sends the phasor data to individual current transformer controllers, for example, the (in Fig. 1 shown) current transformer controls 40 and / or 42. The method 110 also includes the control 132 of the current transformers 28 and / or 32 at least partially on the basis of the phasor data and the voltage output data.

[0034] Method 110 can also include the synchronization 134 of the voltage output of the current transformers 28 and / or 32 to the phasor data. The synchronization 134 can include the control of the current transformers 28 and / or 32 to output a voltage with an angle that is in phase with the voltage measured at the network side 52 of the transmission line 16.

[0035] The procedure 110 can also include the determination 136 of a current output of the current transformers 28 and / or 32 and the determination 138 of an impedance of the transmission line 16, at least partially, based on the current output and the phasor data. The controller 36 can determine the impedance of the transmission line 16, at least partially, based on data received from the PMU 50 and from a local current measuring device, for example, the (in Fig. 1. Current measuring device 17 shown, 138. In particular, the controller 36 can determine the impedance (x) of the transmission line, 138, based on: P≈(v1∗v2x)sin(α1−α2)

[0036] The procedure 110 can also include the determination 140 of a maximum current that the network can absorb, at least partially on the basis of the impedance of the transmission line 16.

[0037] It should be understood that the embodiments described herein are not limited to any specific processor for performing the processing tasks of the invention. The term "processor," as used herein, is intended to denote any machine capable of performing the calculations or estimations necessary to accomplish the tasks of this invention. The term "processor" is also intended to denote any machine capable of accepting a structured input variable and processing the input variable according to prescribed rules to generate an output variable. It should also be noted that the expression "configured for," as used herein, means that the processor is equipped with a combination of hardware and software for performing the tasks of the embodiments of the invention, as is known to those skilled in the art.

[0038] Furthermore, unless otherwise defined, technical and scientific terms used herein have the same meaning as generally understood by a person skilled in the art, to whom this disclosure is addressed. The terms "first...", "second...", and the like, as used herein, do not signify any order, quantity, or importance, but are used merely to distinguish one element from another. Similarly, the terms "one..." do not restrict the quantity, but signify the presence of at least one of the elements referred to. The term "or" is meant to be inclusive and refers to one, some, or all of the elements mentioned.

[0039] The use of "containing," "possessing," or "having," and variants thereof, herein shall include all elements and equivalents listed therein, as well as any additional elements. The terms "connected" and "coupled" are not limited to direct or indirect physical or mechanical connections or couplings. Furthermore, the terms "circuit," "circuit," and "control" may include either a single component or multiple components that are either actively and / or passively connected or otherwise coupled to provide the described function.

[0040] The embodiments described herein may comprise one or more computer-readable media, each medium being configured to contain or containing data or computer-executable instructions for manipulating data. The computer-executable instructions comprise data structures, objects, programs, routines, or other program modules accessible by a processing system, such as one associated with a general-purpose computer capable of performing a limited number of functions. Computer-executable instructions cause the processing system to perform a particular function or group of functions and are examples of program code means for implementing steps and procedures disclosed herein. Furthermore, a particular sequence of executable instructions represents an example of corresponding actions that may be used to implement such steps.Examples of computer-readable media include working memory (“RAM”), read-only memory (“ROM”), programmable read-only memory (“PROM”), erasable programmable read-only memory (“EPROM”), electrically erasable programmable read-only memory (“EEPROM”), a compact disk read-only storage disk (CD-ROM), or any other component or part capable of providing data or executable instructions that can be accessed by a processing system.

[0041] This document describes example procedures, systems, and computer-readable media for controlling the operation of a current transformer, at least partially based on remote power data acquired by a power management unit (PMU). By receiving grid PMU measurements, such as the voltage phase angle, and synchronizing a local phase-locked loop (PLL), a renewable energy generator control system can acquire important information about the grid connection. For example, the control system can determine the grid strength by evaluating power against the phase angle. Furthermore, a phase shift or voltage dip detected by the PMU measurements provides the control system with an indication of a grid fault event. The PMU information enables the control system to adaptively adjust its control parameters to optimize the dynamic response of the power generation system according to the current grid conditions.The PMU information also improves the system's ability to weather a network fault event and maintain synchronization with the network for improved recovery behavior from the network fault event.

[0042] The methods, systems, and computer-readable media described herein enable the efficient and economical control of a power generation system. Example implementations of the methods and systems are described and / or illustrated in detail. The methods and systems are not limited to the specific embodiments described herein; instead, components of each system and steps of each method can be used independently and separately from other components and steps described herein. Each component and each method step can also be used in combination with other components and / or method steps.

[0043] This description uses examples to disclose the invention, including its best embodiment, and to enable anyone skilled in the art to put the invention into practice, including the manufacture and use of all elements and systems and the execution of all processes involved. The patentable scope of the invention is defined by the claims and may include further examples that are apparent to a person skilled in the art. Such further examples shall be included in the scope of the invention if they have structural elements that do not differ from the wording of the claims or if they contain equivalent structural elements with insignificant modifications compared to the wording of the claims.

Claims

[1] Power supply system comprising: at least one conductor having a first end and a second end; a phasor measurement unit (PMU) connected to the first end of the conductor, the PMU being configured to acquire phasor data at the first end and generate a phasor signal containing the phasor data; a power generation system connected to the second end of the conductor and configured to supply power to the conductor, the power generation system comprising a power source, a power converter, and a controller, the controller being communicatively connected to the PMU and configured to receive the phasor signal and to control the power converter based at least in part on the phasor data; and a measuring device that is communicatively connected to the converter control and is set up to: measuring at least one of a voltage and a current flow at the second end of the second conductor; and generate an output current signal including transducer output data representing at least one of the voltage measured at the second end of the conductor and the current flow; wherein the converter controller is further configured to determine an impedance (x) of the conductor based on the converter output data and the phasor data; wherein the converter controller is configured to determine a maximum current that the network can accept based at least in part on the impedance of the conductor. [2] The power system of claim 1, wherein the at least one conductor comprises at least one transmission line configured for at least one of transmitting and distributing power from the power generation system to an electrical grid. [3] The power system of claim 1, wherein the controller is configured to maintain phase synchronization between the power generation system and the electrical grid during a voltage dip event and / or a zero voltage dip event by applying the phasor data for control operation. [4] The power system of claim 1, wherein the power source comprises at least one of a wind turbine generator and a photovoltaic system. [5] The power system of claim 1, wherein the controller comprises at least one of a central system controller and an individual power converter controller. [6] The power system of claim 1, wherein the PMU includes a GPS (Global Positioning System) receiver that receives a time reference signal used to time-stamp the phasor data. [7] The power system of claim 6, wherein the phasor data comprises at least one of a time-stamped current flow phasor associated with the current at the first end of the conductor and a time-stamped voltage phasor. [8] The power system of claim 7, wherein the converter controller comprises a GPS receiver that receives the time reference signal, the converter controller using the time-stamped phasor data as at least one of a voltage reference and a current flow reference to control the power converter. [9] The power system of claim 7, wherein the converter controller controls the current converter to output current that is in phase with the current at the first end of the conductor. [10] A power supply system according to any preceding claim, wherein the converter controller controls the power converter to output current that is less than the maximum current that the electrical network can absorb. [11] A method for controlling at least one current transformer arranged to supply power to an electrical network via a transmission line, the method comprising the steps of: Monitoring a voltage output of the at least one current transformer; Recording voltage output data associated with the voltage output; Receiving a time reference signal and assigning a timestamp to the voltage output data; Measuring a voltage phasor at a first location located at an end of the transmission line opposite the at least one current transformer; Receiving the timing reference signal and associating the timing reference signal with the voltage phasor to generate phasor data; Transmitting the phasor data to a current transformer controller; controlling, using the current transformer controller, the at least one current transformer based at least in part on the phasor data and the voltage output data; Determining a current output of the at least one current transformer; Determining an impedance of the transmission line based at least in part on the current input and the phasor data; and Determining a maximum current that the electrical network can handle based at least in part on the impedance of the transmission line. [12] The method of claim 11, further comprising the step of synchronizing the voltage output of the at least one current transformer with the phasor data. [13] The method of claim 12, wherein the step of synchronizing the voltage output of the at least one current transformer with the phasor data comprises the step of controlling the at least one current transformer to output a voltage at an angle that is in phase with the voltage measured at the first location. [14] A controller arranged to control a current transformer connected to a transmission line having a first end and a second end, the controller comprising: a GPS (Global Positioning System) receiver configured to receive a time reference signal; a storage device configured to store voltage output data associated with a voltage output of the current transformer, the voltage output data including voltage output data measured at the first end of the transmission line at a first time; and Processing facility equipped to: assigning a time reference value to the voltage output data stored in the storage device; to receive phasor data from a phasor measurement unit (PMU) positioned at the second end of the transmission line, the phasor data containing a time reference value linking the phasor data to the first time point, to compare the phasor data of the first time point with voltage output data of the first time point, and to control the operation of the current transformer based at least in part on the phasor data and the voltage output data; to determine a current output of the at least one current transformer; determine an impedance of the transmission line based at least in part on the current input and the phasor data; and to determine a maximum current that the electrical network can absorb, based at least in part on the impedance of the transmission line.

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