Abstract: A partial discharge detection system includes a plurality of partial discharge sensors mounted within an electrical switchgear cabinet and a monitoring device for monitoring the output of the plurality of sensors and outputting at least one output signal based on detected partial discharge activity. A related method for detecting partial discharge activity in an electrical switchgear cabinet, includes the steps of mounting a plurality of partial discharge sensors within the electrical switchgear cabinet and monitoring the output of the plurality of sensors and outputting at least one signal based on detected partial discharge activity.

Abstract: An electricity substation 11 receives a high voltage electricity supply and transforms it to a low voltage supply distributed to a plurality of properties 13. The substation 11 is also provided with a demand management unit 14 incorporating a load monitoring means 15 operable to measure the load on the or each low voltage supply cable 12 and each property 13 is provided with at least one intelligent socket 20 for high load appliances. The intelligent socket 20 comprises contacts 21 for making a connection with the conductors of the charging lead; a use monitor 22 operable to detect when a load (i.e. an electric vehicle) is drawn from the contacts 21; a switch 23 operable to disconnect or connect the electricity supply to the contacts; and a control unit 24. The control unit is operable to communicate with the demand management unit 14 via a suitable communications link 16.

Abstract: A fault current passage indicator (100) is fitted around the earth conductor (11) of a pole (10) supporting a section of an overhead electricity distribution network. This is achieved by means of a clip (110) adapted to provide a loop of ferromagnetic material enclosing the earth conductor (11). The indicator 100 is operable to detect transient earth currents flowing in the earth conductor (11). This is achieved by the provision of a sensor coil (101) is fitted around the clip (110) such that a portion of the clip (110) passes through the core of the sensor coil (101). Detected incidents of transient earth currents are recorded by the indicator (100) and data relating thereto can be retrieved by use of a suitable reader device (200). The indicator (100) is further adapted to scavenge power for operation from either transient earth currents or the reader device (200).

Abstract: There is described a hybrid furnace comprising a microwave source, and an enclosure for the confinement of both microwave and RF energy for containing an object to be heated. The microwave source is coupled to the enclosure. The furnace further includes an RF source coupled to the enclosure, and a controller for controlling the quantity of microwave energy and RF energy to which the object to be heated is exposed. There is also described a method of operating a furnace of the above type to the heat an object. The microwave source is actuated to induce an electric field to heat the object and the RF source is controlled to selectively provide an oscillating electric field within the object to be heated at a location at a temperature where the field strength of the microwave-induced electric field falls below a predetermined threshold value.

Abstract: A microwave furnace (10) of the type comprising a microwave source (14), coupled to an enclosure for the confinement of microwaves and for containing an object to be heated (12). An independently controllable alternate heating (20) is disposed in relation to the enclosure (12) to provide at least one of radiant and convective heating within the enclosure. The method comprises the steps of energizing the alternate heater (20) so as to generate heat substantially throughout the heating cycle of the furnace (10) and controlling the quanity of heat generated in the object y one or both of the microwaves and the alternate heater so as to provide a desired thermal profile in the object. A temperature sensor to measure the ambient temperature within the enclosure (12) can be provided and control circuit (54) responsive to the sensed temperature controls the quanity of heat generated in the object by the microwaves and the alternate heat so as to provide a desired thermal profile within the object.

Abstract: An electric induction motor can be given a kick start without excessive current drain on the supply by first connecting a unidirectional supply to a winding of the motor to build up a stationary rotor flux and then applying a starting current to another winding of the motor to produce a stator flux at an appropriate angle (between 0.degree. and 180.degree.) with the stationary rotor flux. Once the motor has begun accelerating the normal running supply can be connected. This starting current may be derived from a capacitance which is charged up during the period of establishing the stationary rotor flux.

Abstract: A microwave-plasma apparatus produces a plasma substantially at or above atmospheric pressure. A vessel contains gas substantially at or above atmospheric pressure and a plasma once initiated. Microwave energy is radiated into said vessel to produce a plasma therein. The plasma is initiated. The vessel is shaped to confine said plasma in a volume to prevent dissipation of said plasma once initiated, and the device for radiating microwave energy includes a power controller to control the power level of the microwave energy to sustain said plasma once initiated.

Abstract: An method and apparatus is described for mixing solid particulates in a molten metal matrix to form a metal matrix composite product flow. The apparatus a refractory vessel to hold the metal matrix; a refractory conduit in communication with both the inlet and outlet of the refractory vessel so as to define a closed loop flow path. The inlet and outlet is spaced so as to encourage mixing within the vessel. A pump is provided to circulate the metal matrix to effect mixing. The apparatus and method further includes the metal matrix having a head with a vertical dimension in the excess of four times the cross sectional width of the conduit.

Abstract: A heating control apparatus for use in a heating system having heaters for heating at least one location and temperature sensors for measuring the temperature of each location is disclosed. The heating system is connected to an electricity supply having a tariff which varies with time. The heating control apparatus comprises a data receiving arrangement for receiving data on the tariff and weather prediction information. A selector is provided which is operable by a user to select the desired temperature for each location and a desired time and duration of the desired temperature. A controller includes a memory for storing information on the thermal characteristics of each location and the heaters and is responsive to the data, the measured temperature and the temperature selected by the user as well as the stored information to determine the times at which the heaters are to be energised. The controller then controls the heaters in order to achieve the desired temperature in each location.

Abstract: A process for converting ammonia in a gas stream to nitrogen comprises contacting the gas stream with an electrolyte containing bromide and hypobromite ions. The ammonia is dissolved and oxidized by the hypobromite ions to nitrogen. Thereafter the electrolyte is passed through an electrochemical cell containing an anode and a cathode to regenerate the hyperbromite ions by the action of an electric current flowing across the cell. The conversion of ammonia to nitrogen in accordance with the invention is adventageous as nitrogen may be disposed of without harm to the environment whilst ammonia has toxic effects.

Abstract: Cold storage apparatus comprises a vessel (1) containing a storage liquid and a heat transfer liquid in direct contact with the storage liquid to transfer heat thereto or therefrom. The liquids are immiscible and of different densities and the heat transfer liquid remains liquid during heat transfer. The storage liquid comprises a liquid which solidifies when sufficiently cooled by the heat transfer liquid and the solidified storage liquid is of a different density to the storage liquid. The liquids form by gravity sequentially within the vessel (1) a first layer (4) of heat transfer liquid, a second layer (3) of storage liquid and a third layer (2) of solidified storage liquid. The cold storage apparatus includes heat transfer liquid circulating means (6) to deliver the heat transfer liquid to and from vessel (1).

Abstract: A process for the destruction of a halocarbon, which process comprises reacting the halocarbon with molten sodium at an elevated temperature to produce the corresponding sodium halide or halides in a sludge in the molten sodium and separating the sludge from the molten sodium.

Abstract: Induction heating apparatus for heating an elongate metal workpiece of predetermined width generates time varying magnetic fields which produce longitudinal eddy current distributions across the width of the workpiece having cosine and sine profiles. The amplitude of these profiles is not necessarily uniform across the width of the workpiece and the spatial period of these profiles across the workpiece width are chosen to ensure that the line integral across the workpiece of the eddy currents is zero. In this way a desired heating profile across the width of the workpiece can be maintained.