Abstract: Disclosed is a method for reducing the variation in voltage, due to Ferranti effect, using the impedance injection capability of distributed impedance injection modules. The Ferranti effect is an increase in voltage occurring at the receiving end of a long transmission line in comparison to the voltage at the sending end. This effect is more pronounced on longer lies and underground lines when the high-voltage power lines are energized with a very low load, when there is a change from a high load to a very light load, or the load is disconnected from the high-voltage power lines of the power grid. This effect creates a problem for voltage control at the distribution end of the power grid.

Abstract: Distributed static synchronous series compensators (DSSSCs) which may also be designated tower routers capable of injecting series inductive or capacitive impedances to enable distributed power-flow control. When a large number of these (a fleet of) DSSSCs are distributed over the grid for power-flow control, it is necessary to ensure that coordinated communication and control capabilities are also established, enabling fast reaction to changes that can exist across the grid. A system architecture and method for enabling localized high-speed low-latency intelligent control with communications between subsections (local network) of the grid along with communication to the central Grid operations center at the utility for supervisory control is disclosed herein.

Abstract: This patent discloses an active impedance-injection module for dynamic line balancing of a high-voltage (HV) transmission line. The impedance-injection module comprises a plurality of transformers each having a primary winding in series with a HV transmission line. Each transformer also has secondary windings, each connected to an individual electronic converter. The plurality of secondary windings are electrically isolated from the associated primary winding and extract power from the HV transmission line for operation of the converters and other circuits connected to the secondary windings. The active impedance-injection module is enabled to generate a controlled impedance, inductive or capacitive, to be impressed on the HV transmission line.

Abstract: The disclosure is generally directed to reactance modules or DSRs (30) that may be mounted on a power transmission line (16) of a power transmission system (400). A DSR (30) may be configured in a bypass mode or in an injection mode (where reactance is injected into the corresponding line (16)). Multiple DSRs (30) installed on a power line section (18) define an array (410) and have a dedicated controller (440). Such an array (410) and controller (440) may be installed on a number of different power line sections (18). The controller (440) for each array (410) may communicate with a DSR server (420), which in turn may communicate with a utility-side control system (430). Each DSR (30) may incorporate one or more features directed to core (50) configurations and assembly, communications, modal configuration control, fault protection, EMI shielding, DSR (30) assembly, and DSR (30) installation.

Abstract: An installation fixture for installing a device on a power line is disclosed. The fixture includes a lower cradle that may receive one part of the device, an upper cradle that may receive another part of the device, and a base. The installation fixture may be installed on a worker carrier for a boom truck or the like. The orientation of the lower cradle may be adjusted relative to the base to facilitate the installation on the power line. The upper cradle may be moved between an open position (where the parts may be loaded into the fixture) and a closed position (where the power line is captured between the two parts of the device) and at which time that parts can be secured together.

Abstract: A device for use in a power transmission system to sense GICs. The device may be a part of a reactance-injecting device on a power line, it may be a standalone device, or it may be a part of another type of device. The device may include a sensor to sense magnetic fields (e.g., a Hall effect sensor). The sensor may be positioned in the air gap of a magnetic core formed concentrically around the power line. The signal from the sensor may be converted to a digital signal and separately processed to determine the magnitude of the AC current and the magnitude of the DC (or quasi-DC) current. If the output signal of another A/C current sensor is available, that output signal may be used to adjust/calibrate the determined magnitude of the DC current. The sensor may communicate with other devices in a network to provide GIC information.

Abstract: The disclosure is generally directed to reactance modules or DSRs (30) that may be mounted on a power transmission line (16) of a power transmission system (400). A DSR (30) may be configured in a bypass mode or in an injection mode (where reactance is injected into the corresponding line (16)). Multiple DSRs (30) installed on a power line section (18) define an array (410) and have a dedicated controller (440). Such an array (410) and controller (440) may be installed on a number of different power line sections (18). The controller (440) for each array (410) may communicate with a DSR server (420), which in turn may communicate with a utility-side control system (430). Each DSR (30) may incorporate one or more features directed to core (50) configurations and assembly, communications, modal configuration control, fault protection, EMI shielding, DSR (30) assembly, and DSR (30) installation.

Abstract: A device for use in a power transmission system to sense GICs. The device may be a part of a reactance-injecting device on a power line, it may be a standalone device, or it may be a part of another type of device. The device may include a sensor to sense magnetic fields (e.g., a Hall effect sensor). The sensor may be positioned in the air gap of a magnetic core formed concentrically around the power line. The signal from the sensor may be converted to a digital signal and separately processed to determine the magnitude of the AC current and the magnitude of the DC (or quasi-DC) current. If the output signal of another A/C current sensor is available, that output signal may be used to adjust/calibrate the determined magnitude of the DC current. The sensor may communicate with other devices in a network to provide GIC information.

Abstract: Phase balancing techniques for power transmission systems are disclosed. In one embodiment, a phase balancing protocol (240) includes executing a first phase balancing protocol (350) in relation to a first power transmission section (400a). A second phase balancing protocol (370) may be executed if the first phase balancing protocol (350) is unable to provide a phase balanced condition. The first phase balancing protocol (350) may utilize a first ordering sequence (364) to rank the current flow on the power lines (16) of the first power transmission section (400a), while the second phase balancing protocol (370) may utilize a second ordering sequence (384) to rank the current flow on the power lines (16) of the first power transmission section (400a). The order sequences (364, 384) are opposite of each other—one ranks the current flows from high-to-low, and the other ranks the current flow from low-to-high.

Abstract: An installation fixture for installing a device on a power line is disclosed. The fixture includes a lower cradle that may receive one part of the device, an upper cradle that may receive another part of the device, and a base. The installation fixture may be installed on a worker carrier for a boom truck or the like. The orientation of the lower cradle may be adjusted relative to the base to facilitate the installation on the power line. The upper cradle may be moved between an open position (where the parts may be loaded into the fixture) and a closed position (where the power line is captured between the two parts of the device) and at which time that parts can be secured together.