Abstract:
A load tap changer comprising in part a diverter switch is disclosed. The diverter switch includes a movable main contact (38), first and second fixed main contacts (40a, 40b), a pantograph system (30) for translating a rotational motion of a shaft (22) to a substantially linear motion of the movable main contact. The load tap changer further comprises a link system (10) comprising a gear adapted to be rotated by a motor, a spring battery for storing energy of the motor and a link assembly for coupling the gear to the spring battery. The shaft is coupled to the link assembly to enable the spring battery to rotate the shaft and effect movement of the movable main contact. A predetermined amount of rotation of the shaft effects a movement of the main contact from a contacting position with the first fixed main contact to a contacting position with the second fixed main contact.
Abstract:
A process for making an insulated conductor in accordance with the present invention includes extruding an insulative material onto a conductor and subsequently rolling the insulative material on the conductor to a prescribed thickness. The extruding step comprises extruding the insulative material to a thickness of about 0.0025 inch to about 0.0035 inch, and the rolling step comprises rolling the insulative material to a thickness of about 0.00125 to about 0.00315 inch.
Abstract:
A dynamic mechanically-switched damping (DMSD) system is described which utilizes one or more mechanical switches and appropriate controls to switch series or shunt reactive impedances (14) in order to provide power oscillation damping in power systems. The DMSD system provides a controller (16) which can be configured based on the number of mechanical switches in the DMSD system, the type of reactive impedances interfaced to the power system by each switch and the magnitude of each of the reactive impedance. The DMSD system monitors parameters of the power system (17, 18) and the controller generates a modulation signal based on the monitored parameters. The modulation signal is processed to identify a reactive impedance of the available DMSD system reactive impedances required to damp power oscillations. Appropriate switches (32) are selected for supplying the required reactive impedance. A switching control signal is generated and output to each of the selected switches to synchronously open or close the switch at a predetermined instant.
Abstract:
A numerical comparator (20) is disclosed. The numerical comparator (20) employs numerical techniques based upon the behavior of the cylinder unit (18) to compare phasors in real time. In one application of this invention, the torque signal generated by the numerical comparator, Mk+1, is employed to determine whether a fault has occurred in a transmission line. Another application involves employing the output Mk+1 to determine the direction of power flow in the transmission line. In yet another application, the output Mk+1 is used to determine whether a voltage or current has exceeded a predetermined threshold.
Abstract:
The movable nozzle (95) of a puffer circuit interrupter (15-17) has a coaxial cylindrical shield (110) connected to its downstream end and the main movable contacts (89) connected to its upstream end. The shield (110) is electrically connected to the stationary contact terminal (44). The movable contact ring (89) and coaxial shield (110) at the upstream end of the nozzle (95) define a well shielded open gap when the interrupter gap opens.
Abstract:
Magnetic core structure of the stacked type having outer legs (11, 12), at least one inner leg (13), and top (14, 15) and bottom yokes (16, 17) formed of a plurality of stacked groups of layers of metallic laminations. The yoke and leg laminations have their ends cut diagonally to provide a closed magnetic circuit having diagonal joints between adjoining ends of the yoke and leg laminations. The length dimensions of the inner leg laminations are uniform from layer to layer within each group, while the junction of the diagonally cut ends of the inner leg laminations are offset from the centerline thereof from layer to layer in a step pattern that progresses an equal number of steps on each side of the centerline of each group of layers of inner leg laminations to be step dependent. The configuration of the outer leg laminations and the top and bottom yoke laminations are uniform from layer to layer within each group to be step independent. A method of stacking the laminations in groups is disclosed and there is also disclosed a method of making the center or inner laminations of the magnetic core structure in two parts where the width of the laminations is greater than the commercially available lamination material.
Abstract:
An intelligent circuit breaker or switching device system comprises three separate microprocessor-based units, including a condition monitoring unit (CMU) (40), a breaker control unit (BCU) (50), and a synchronous control unit (SCU) (60). The CMU (40) provides detailed diagnostic information by monitoring key quantities associated with circuit breaker or switching device reliability. On-line analysis performed by the CMU provides information facilitating the performance of maintenance as needed and the identification of impending failures. The BCU (50) is a programmable system having self-diagnostic and remote communications. The BCU replaces the conventional electromechanical control circuits typically employed to control a circuit breaker or switching device. The SCU (60) provides synchronous switching control for both closing and opening the circuit interrupters. The control processes carried out by the SCU reduce system switching transients and interrupter wear. The intelligent circuit breaker or switching device system improves system operation and equipment maintenance.
Abstract:
A steel plate (130) of area greater than the area of the output of a nozzle (95) in a puffer gas interrupter (15-17) is fixed to but is spaced from the downstream end of the nozzle (95) and causes turbulence in the hot interrupter gases flowing through the nozzle (95) to improve mixing with cooler downstream gas.
Abstract:
An interrupter assembly (10) comprises an interrupter switch (12) and at least one condition sensing device (32) embedded within a body of solid dielectric material. Preferably, the solid dielectric material is a polymer concrete or an epoxy-concrete. The condition sensing device (32) may comprise a current sensor (32) and/or a voltage sensor (38).
Abstract:
A circuit switching mechanism for use in a high voltage circuit breaker is disclosed. The circuit switching mechanism includes a charging system (12); trip latch mechanism (14); a closing spring (18) positioned coaxially within an opening spring (16); a support structure (22) supporting the springs; and a first rod member (24) operatively associated with a circuit interrupter. Discharging of the opening or closing spring effects movement of the first rod member in a first direction and a second direction, respectively. The trip latch mechanism (14) comprises a hammer (14-6); a trip link (14-18); a first pin (14-16) coupled through the hammer and trip link; a second pin (14-30) attached to the trip link, a trip finger (14-20) and a third pin (14-24) coupled through the trip link and the trip finger. The trip finger bears against the support structure to hold at least one spring in a charged state.