Abstract: The molten salt solar tower system 100 is provided for controlling molten salt temperature in a solar receiver 130 for effective operation of the system 100 while without degrading physical properties of molten salt. The system 100 includes two circuits, first 140 and second 150. The first circuit 140 is configured to supply relatively cold molten salt in the solar receiver 130 for heating, and the second circuit 150 is configured to supply a predetermined amount of the relatively cold molten salt in the first circuit 140, as and when the temperature of the relatively hot molten salt circulating through the solar receiver 130 exceeds a predetermined set temperature value thereof.

Abstract: For application to medium- and high-voltage circuit breakers, the control device makes it possible to actuate opening of the circuit breakers used in the medium- and high-voltage networks very quickly. The spring used in the control device is a spring of the composite type, having a curved C- or ?-shape. The spring has a stationary first end and a movable second end that is pivotally connected to the end of a lever device, that is itself constrained to rotate with the drive shaft of the control device.

Abstract: The invention relates to a spring controller for high- or medium-voltage electric switchgear, the controller having a free-wheel coupling device between a crank handle or a motor and the drive shaft (1) for driving a switch contact of the switchgear and respectively providing coupling while the spring(s) (11) is/are being loaded and decoupling while the spring(s) is/are being released. The free-wheel mechanical device is incorporated in a toothed wheel (2) of the controller and includes at least one pawl (7, 70) meshing or not meshing with an inner set of teeth (4) of the toothed wheel (2).

Abstract: The invention relates to a method and a device for locating an event transmitting a signal, including a set of sensors (Ai-Am) to measure the response times of the said signal, and processing means (3) to solve a system of equations defining distances between the said sensors and the said event as a function of a speed of propagation of the said signal and of an offset of the said response times relative to a reference time, where the device also includes: processing means (3) to recommence multiple times the solution of the system of equations, each time modifying the response time of at least one of the said sensors according to a local variation, and processing means (3) to determine the location of the event as a function of the positions obtained when the different solutions of the system of equations are found.

Abstract: A decision-support tool is provided to evaluate operational and financial performance for dispatchers in power grid control centers associated with utility systems. A scheduler engine is coupled to a comprehensive operating plan that applies after the fact analysis for performance metrics, root-cause impacts and process re-engineering. A relational database is coupled to a data archiver that captures actual system and resource conditions and then supplies the system and resource conditions to the relational database. The scheduler engine receives the actual system and resource conditions from the relational database and processes it to calculate system performance.

Abstract: The invention relates to a bidirectional multi-level DC/DC converter and its non-linear control, adapted to transfer power between at least one energy source and an electricity distribution network.

Abstract: A head assembly for a pulverized coal nozzle includes removeable wear-resistant inserts having vanes. The vanes may be flat or curved to direct a stream of air and pulverized solid fuel particles from the inlet port toward the outlet port. The curved vanes curve in two dimensions to evenly distribute the stream of air and pulverized solid fuel away from the outer surfaces reducing wear and corrosion. The pipe elbow has a removable cover that allows for easy access. The vanes are attached to a wear-resistant replaceable liner thus allowing them to be easily removed and replaced. The wear-resistant liner may be made from several parts for ease of removal and replacement.

Abstract: The invention provides electric power line switchgear (10) comprising a main movable contact (14) and a secondary movable contact (16), capable of moving along a main axis A of the switchgear (10), in which the main movable contact (14) is connected to the secondary movable contact (16) by means of a crank mechanism (20) that transforms the movement of the main movable contact (14) in one direction into a movement of the secondary movable contact (16) in an opposite direction; the switchgear being characterized in that the crank mechanism (20) comprises two levers (22, 24) mounted to pivot relative to the stationary housing (12) about respective parallel pivot axes (B, C), each lever (22, 24) being connected firstly to a respective one of the main movable contact (14) and the secondary movable contact (16), and secondly to the other lever (24, 22).

Abstract: A series spark gap includes at least three partial spark gaps. In a continuous operation mode, a supply voltage acting over the partial spark gaps is divided by a first voltage dividing mechanism. During triggering, more than half of the partial spark gaps are bypassed by using a bypass mechanism such that more than half of the supply voltage acts over the partial spark gaps that are not bypassed, whereby the partial spark gap or the partial spark gaps that are not bypassed ignite. The voltage acting over the bypassed partial spark gaps is divided asymmetrically using the bypass mechanism, whereby the bypassed partial spark gaps ignite sequentially in the order determined by the asymmetric voltage division.

Abstract: A method of determining a communication time delay in a communication network between a local terminal and one or more remote terminals within an electrical power network includes: selecting, in respect of the or each remote terminal a calculation node in the electrical power network; calculating respective node currents flowing into the corresponding calculation node from the local terminal and the or each remote terminal; equating, in respect of the or each remote terminal, a sum of node currents flowing into the corresponding calculation node to zero according to Kirchhoff s first law; and extracting, in respect of the or each remote terminal, a communication time delay between the local terminal and the said respective remote terminal from a corresponding equated sum of node currents.

Abstract: Circuits comprising at least one energy storage device, a resistor and switch arranged in series with the resistor are described. The energy storage device is arranged in parallel with the series connection of the switch and the resistor, and the switch is arranged to selectively switch the resistor into a parallel connection to the energy storage device. In some examples, the switch comprises a series connection of semiconductor switching elements. In some examples, the circuit may comprise a sub-module for use in a multilevel modular converter.

Abstract: An arc-control chamber gear for contact electrodes, the gear possessing openings in collars of an electrode centering cap so as to break the confinement of the electrodes and allow them to be ventilated by gas convection between the inside volume heated by the flow of current and the cooler outside volume.

Abstract: A combustion device (10) includes at least one combustion chamber (11) with a plurality of burners (B1, . . . , Bn) operating in parallel which produce in each case a flame (F1, . . . , Fn) which reaches into the combustion chamber (11), wherein each of the burners (B1, . . . , Bn), via a fuel distribution system (18), is supplied with a fuel from a fuel supply (16), which fuel distribution system (18) includes control elements (V1, . . . , Vm) for manual or controlled regulating of the fuel supply and/or fuel composition of individual burners (B1, . . . , Bn) and/or groups of burners (B1, . . . , B3; Bn?2, . . . , Bn). In a method of using the combustion device, a quick optimization or homogenization is achieved by a function (F) of the flame temperatures of the burners (B1, . . . , Bn) being provided in dependence upon the positions of the control elements (V1, . . .

Abstract: The invention relates to the domains of power electronics and electric power transmission systems and concerns a new structure for wall bushings for High and Ultra High Voltage AC or DC applications. The wall bushing is remarkable as it can be assembled as a kit of two replaceable modules: a plug type module (20) and a socket type module (30) whose central conductors (15a,15b) are connected by a joint that allows their thermal expansion.

Abstract: An AC/DC electrical converter device having a source mode and a recovery mode, and for connection, on the AC side, to an AC voltage source and, on the DC side, to a DC power distribution network. It includes an AC/DC converter, a switching cell with two switches (K1, K2) that are bidirectional for current, the switches sharing a common point (A) and each having a respective end terminal (B1, B2), a filter stage, and a control unit for the cell; the converter is for connection on the AC side to the voltage source and is connected on the DC side to the cell; in use, the first switch (K1) is connected between the converter and the DC power distribution network via the filter stage, the second switch (K2) forming a combination in parallel with the filter stage and the DC power distribution network. The control means are able to manage a short-circuit current in source mode by operating on the first and second switches.

Abstract: Power converters are disclosed. One power electronic converter for connecting AC and DC electrical networks and transferring power therebetween includes a converter limb extending between two DC terminals and having limb portions separated by an AC terminal. Each limb portion includes a chain-link converter including at least one rationalized module that has first and second sets of series-connected current flow control elements connected in parallel with at least one energy storage device. The current flow control elements and energy storage device(s) in each rationalized module combine to selectively provide a voltage source to control the configuration of an AC voltage at the AC terminal. The converter further includes a controller to selectively control the switching of the current flow control elements to simultaneously switch both limb portions into circuit to form a current circulation path including the converter limb and the DC electrical network.

Abstract: A DC to DC converter assembly, for connecting first and second high voltage DC power transmission networks, comprising first and second modular multilevel converters, each converter including a first converter limb having first and second limb portions, each limb portion including a least one module switchable to selectively provide a voltage source and thereby vary the magnitude ratio of a DC voltage (V1, V2) across the first and second terminals of a respective converter and an AC voltage (VAC) at the third terminal of the corresponding converter, the DC to DC converter assembly further including a first link electrically connecting the third terminal of one converter, with the third terminal of the other converter, and at least one converter further including a controller configured to switch the first and second limb portions in the first converter limb of the said converter into simultaneous conduction to divert a portion (IDiV1) of current flowing within the said converter away from the first link.

Abstract: A disconnector (1) including a movable conductive unit (6) comprising a main electrically conductive body (9) has a main contact (4b) as well as an arcing contact (5b). According to the invention, the unit (6) further comprises a secondary body (14) mounted to move in sliding relatively to the main body (9) along a movement direction (11) of the unit (6), the secondary body (14) being designed to be connected to a connection point (22) of a drive device of the unit (6), the unit further comprising resilient return means (16) interposed between the bodies (9, 14), the switchgear being designed so that during an opening operation the resilient return means (16) can firstly store energy as a result of the secondary body (14) moving relative to the main body (9), and can then release the stored energy in order to cause the main body (9) to accelerate.

Abstract: The invention relates to a method of controlling switchgear in order to estimate the remanent flux value of a power transformer during disconnection from a high-voltage electrical network using voltage measurements delivered by a capacitive voltage transformer by correcting the transfer function of the capacitive voltage transformer, and in which said value is delivered to a controller that determines the optimum switchgear switching instant.

Abstract: A solar thermal power system includes a solar receiver and a thermal energy storage arrangement including thermal energy storage fluid to be circulated through the solar receiver to store thermal energy. The system includes a multistage steam turbine operable on variable pressure steam generated by primary and secondary arrangements, by utilizing the fluid. The primary arrangement generates and supplies a high pressure steam to a high pressure turbine inlet, and exits from a high pressure turbine outlet. The secondary arrangement having a reheat assembly, to generate an intermediate pressure steam from the fluid, received from the storage arrangement through the reheat assembly. The intermediate pressure steam and released steam from a high pressure turbine outlet are mixed and reheated in the reheat assembly to be supplied to an intermediate pressure turbine inlet.