A device for utilizing groundwater, characterized by an upper well shaft and an upper well water reservoir having a first water level; a lower well shaft and a lower well water reservoir having a second water level; wherein the second water level is lower than the first water level; a water line between the upper well water reservoir and the lower well water reservoir including a first line extending downwardly inside the well shaft of the upper well and into the upper well water reservoir, a second line extending downwardly inside the well shaft of the lower well and into the lower well water reservoir, and a connecting line connecting the first branch line and the second branch line; at least one turbine coupled to the water line; and an electrical generator coupled to the at least one turbine for delivering electric power to the power grid.

A device for utilizing groundwater, characterized by an upper well shaft and an upper well water reservoir having a first water level; a lower well shaft and a lower well water reservoir having a second water level; wherein the second water level is lower than the first water level; a water line between the upper well water reservoir and the lower well water reservoir including a first line extending downwardly inside the well shaft of the upper well and into the upper well water reservoir, a second line extending downwardly inside the well shaft of the lower well and into the lower well water reservoir, and a connecting line connecting the first branch line and the second branch line; at least one turbine coupled to the water line; and an electrical generator coupled to the at least one turbine for delivering electric power to the power grid.

A field coil type rotating electric machine includes a rotor where both a series resonant circuit including a first winding and a capacitor and a parallel resonant circuit including a second winding and the capacitor are formed. The first winding is radially located closer than the second winding to a stator. The capacitance of the capacitor and the ratio of the number of turns of the second winding to the number of turns of the first winding are set to have the amplitude of a total resultant magnetic flux lower than the amplitude of a field resultant magnetic flux. The total resultant magnetic flux is the resultant of the field resultant magnetic flux and magnetic flux generated by harmonic currents flowing in phase windings of a stator coil. The field resultant magnetic flux is the resultant of magnetic fluxes generated by harmonic currents flowing in the first and second windings.

A system for load balancing on a multi-phase power line connected to a single phase lateral power line, includes a contactor configured to selectively connect each phase of the multi-phase power line to the single phase lateral power line. There is a phase change device connected in parallel with the contactor and a controller. During the phase change state, the controller connects the input of the phase change device to the multi-phase power line and connects the output of the phase change device the single phase lateral power line. The controller causes the phase change device to output a voltage to the single phase lateral line initially aligned with the first phase and then rotated to align with the second phase and causes the contactor changes connection to the second phase of the multi-phase power line and disconnect the phase change device from the power lines.

A system for load balancing on a multi-phase power line connected to a single phase lateral power line, includes a contactor configured to selectively connect each phase of the multi-phase power line to the single phase lateral power line. There is a phase change device connected in parallel with the contactor and a controller. During the phase change state, the controller connects the input of the phase change device to the multi-phase power line and connects the output of the phase change device the single phase lateral power line. The controller causes the phase change device to output a voltage to the single phase lateral line initially aligned with the first phase and then rotated to align with the second phase and causes the contactor changes connection to the second phase of the multi-phase power line and disconnect the phase change device from the power lines.

A de-exciting system for dissipating energy from an inductive circuit that comprises at least one coil adapted to be attached to said inductive circuit and comprising a series connection of a discharge resistor and a unidirectional discharge switching element; a unidirectional bypass switching element that is connected in parallel to the discharge resistor such that, when the de-exciting system is attached to the inductive circuit and both the discharge switching element and the bypass switching element are in a conducting state, a closed conducting path comprising the coil, the discharge switching element, and the bypass switching element is formed; and a control device configured to, in a first de-excitation phase, switch both the discharge switching element and the bypass switching element into a conducting state, and in a second de-excitation phase, switch the bypass switching element into a non-conducting state, while keeping the discharge switching element in the conducting state.

A main field connection to connect to a main field winding has a semi-cylindrical portion with an axially thicker outer surface, an axially thinner inner surface, with an aperture. An extending portion extends from the semi-cylindrical portion to a remote extending end. The remote extending end extends for a first axial distance. The axially thicker portion of the semi-cylindrical portion extends for a second axial distance. A ratio of the first axial distance to the second axial distance is between 0.65 and 1.4. A rotating assembly, a generator and a method are also disclosed.

An assembly comprises an AC (alternating current) housing connection block and a plurality of inserts seated in the AC housing connection block, wherein for each of the inserts, an interface between the insert and the housing is continuous. A method includes inserting a plurality of inserts into a mold; and molding an AC (alternating current) housing connection block.

An assembly comprises a resistor support housing for a rotating rectifier assembly (RRA). A shaft bore is defined through the resistor support housing for passage of a shaft of an electrical machine. The resistor support housing defines a main annular body around the shaft bore. An end housing is mounted to one axial end of the resistor support housing. The end housing defines a portion of the shaft bore therethrough.

An assembly comprises a resistor plate for a rotating rectifier assembly (RRA). A shaft bore is defined through the resistor plate for passage of a shaft of an electrical machine, and the resistor plate defines a main annular body around the shaft bore. A first protrusion extends radially outward from the main annular body, so that a first pin bore extends through the first protrusion. At least one contact band is seated in a the pin bore of the resistor plate for mounting a direct current (DC) pin to the resistor plate.