A control system for a single-axis solar tracking system includes a controller that communicates control signals. An alternating current (AC) powerline is connected to the controller. The AC powerline supplies power control for one or more solar tracker drive motors and propagates the control signals to the one or more solar tracker drive motors.

The present invention is directed, in part, to electrical components and methods of use associated with such components. In particular, the invention relates to an electrical device and improved method of back feeding energy generated from alternative energy devices such as solar panels, wind turbines, fuel cells, electrical generators and other alternative energy sources, to the utility without the necessity of installing a sub panel or replacing an existing panel, resulting in significant cost savings for the user and increased electrical energy available to the power grid. The invention further discloses installation of a back feed circuit breaker into an existing main panel and main circuit breaker thus, eliminating the need of a home owner to completely reinstall a new electrical system in order to install alternative energy sources such as for example, solar panels and the like.

Embodiments of the present invention include control methods employed in multiphase distributed energy storage systems that are located behind utility meters typically located at, but not limited to, medium and large commercial and industrial locations. Current solutions for these types of electric load locations entail multiple discrete energy storage systems, where if any piece of an energy storage system is damaged, the ability of the complete power control strategy at the entire electric load location is at risk of becoming inoperable. Some embodiments of the invention include hardware and methods for dynamically reconfiguring networks of distributed energy storage systems that are able to provide automatic site layout discovery using a formed auto-discovering network formed at an electric load location.

A hydraulic fracturing system for fracturing a subterranean formation is disclosed. In an embodiment, the system may include a plurality of electric pumps fluidly connected to a well associated with the subterranean formation and powered by at least one electric motor, and configured to pump fluid into a wellbore associated with the well at a high pressure so that the fluid passes from the wellbore into the subterranean formation and fractures the subterranean formation; at least one generator electrically coupled to the plurality of electric pumps so as to generate electricity for use by the plurality of electric pumps; and at least one switchgear electrically coupled to the at least one generator and configured to distribute an electrical load between the plurality of electric pumps and the at least one generator.

The embodiments of the present invention provide a cellular power supply network, an intelligent gateway and a power supply control method thereof. The cellular power supply network further comprises: at least one cellular power supply layer formed by a plurality of transformers connected as a cellular structure. In the embodiments of the present invention, the electricity energy can be transferred from one transformer to another transformer demanding power as needed, so that the power is more reasonably distributed and the energy utilization rate is improved. In the technical solutions of the present invention, when a certain transformer cannot work normally due to a fault, the electricity energy outside the transformer can be introduced into the user of the transformer using the cellular power supply network, so as to keep continuous power usage. Meanwhile, the transformer can be separated from the power supply network for repairing and maintenance.

The present invention belongs to electric power engineering field, relates to a method for obtaining a set of symmetric power transfer coefficients under simultaneous change of sources and loads in AC power networks, which comprises the steps of: firstly establishing a linear function of a lossy branch transferred power in terms of buses voltage angles according to a nonlinear function of a branch transferred power, parameters and operation features of the AC power network; then establishing symmetric linear functions of buses injection powers of power sources and loads in terms of buses voltage angles by combining the linear function of the lossy branch transferred power in terms of buses voltage angles and buses injection powers of power sources and loads, in turn establishing symmetric linear functions of buses voltage angles in terms of buses injection powers of power sources and loads; and finally obtaining the symmetric power transfer coefficients from buses injection powers of power sources and loads to the lossy branch transferred power under simultaneous change of sources and loads by using the linear functions just mentioned above. The obtained set of symmetric power transfer coefficients is unique, follows electric circuit laws, is applicable for the practical situations that power sources and loads change at the same time and transmission losses need considering in the AC power network, and truly reflects the substantive characteristics of the power transfer from bus injection powers to branch transferred powers.

A method for controlling a power distribution network includes receiving, by an electronic processor, a fault indication associated with a fault in the power distribution network from a first isolation device of a plurality of isolation devices. The processor identifies a first subset of a plurality of phases associated with the fault indication and a second subset of the plurality of phases not associated with the fault indication. The first and second subsets each include at least one member. The processor identifies an upstream isolation device upstream of the fault. The processor identifies a downstream isolation device downstream of the fault. The processor sends an open command to the downstream isolation device for each phase in the first subset. Responsive to the first isolation device not being the upstream isolation device, the processor sends a close command to the first isolation device for each phase in the first subset.

A method for characterizing power quality events in an electrical system includes deriving electrical measurement data for at least one first virtual meter in an electrical system from (a) electrical measurement data from or derived from energy-related signals captured by at least one first IED in the electrical system, and (b) electrical measurement data from or derived from energy-related signals captured by at least one second IED in the electrical system. In embodiments, the at least one first IED is installed at a first metering point in the electrical system, the at least one second IED is installed at a second metering point in the electrical system, and the at least one first virtual meter is derived or located at a third metering point in the electrical system. The derived electrical measurement data may be used to generate or update a dynamic tolerance curve associated with the third metering point.

A static transfer switch is provided for supplying power to a load alternately from two different power sources. Switching between the two power sources may occur within a fraction of one electrical cycle. In response to sensing degraded performance in the power source supplying the load, resonant turn off circuits connected directly to the main switches of two phases of the power source are actuated to commutate the respective main switches. The main switch of the third phase is commutated with one or more of the resonant turn off circuits through the delta side of a transformer connected to the three phases of the power source.

The present disclosure relates to a shared transfer switching system with built in relay testing ability, for transferring power received by a load from a preferred AC power source to an alternate AC power source, or transferring power being received by the load from the alternate AC power source to the preferred AC power source. The system selectively controls various ones of the relays used to apply power from either the preferred or alternate power sources to the load, such that the relays are switched from open to closed states at controlled times, while voltage measurements are made at select locations between the relays. The system can identify which specific ones of a plurality of relays associated with each of the preferred and alternate power sources has properly opened and closed, and thus verify that all of the relays needed to switch between the preferred and alternate power sources are operating properly.