Abstract: There is provided a method and control system for reducing noise in a power converter by controlling a switching device in the power converter according to a modulation scheme. The switching device couples a direct current (DC) source to provide an alternating current (AC) output at a particular switching frequency. The method includes the step of, in each switching period, switching the switching device between active configurations providing a finite voltage at the output and inactive configurations providing a zero voltage at the output. The ratio between the total period of time in which the switching device is in an active configuration and the total period of time in which the switching device is in an inactive configuration is the same for each switching period and is determined according to the desired voltage at the AC output.

Abstract: There is described an electronic assembly comprising a structure and a printed circuit board (PCB) connected to the structure to form a duct. The PCB has a first side arranged to receive one or more heat-generating components, and a second side. The PCB comprises one or more apertures formed therein. The electronic assembly further comprises airflow generating means arranged to generate an airflow along the duct and along the second side of the PCB such that air is forced through the one or more apertures. By forming a duct beneath a PCB and allowing air to be forced through apertures formed in the PCB, more efficient cooling of components on the PCB may be achieved. For example, the position of the apertures may be tailored such that specific components, or specific parts of components, may be exposed to airflow through the apertures.

Abstract: There is provided a device (50) for locking to a DIN rail (10). The device comprises a shaft (20) defining an axis of rotation, and first and second rail-engaging members (30a, 30b) connected to the shaft. The rail-engaging members are each shaped to engage a DIN rail in a respective engaging position. The shaft is rotatable about the axis of rotation and thereby arranged to urge each rail-engaging member into its respective engaging position with a DIN rail positioned between the first and second rail-engaging members. The invention provides for a means of locking a device to a DIN rail. Once locked to the DIN rail, an electrical component such as a circuit breaker or the like may be mounted or coupled to the device. The locking device may provide for rapid removal/attachment to the DIN rail. Equipment may either be mounted directly to the locking device or indirectly by mounting the component or electrical equipment to a platform or other support that is itself attached to the locking device.

Abstract: An apparatus for producing a compensated voltage output comprising: a first power source or power sink coupled between a first node and a reference node; a second power source or power sink coupled between a second node and the reference node; a biasing means comprising one portion coupled between the first node and the reference node, and another portion coupled between the first node and the second node. The biasing means is operable to generate a controllable bias voltage of either polarity between the first and second nodes to produce the compensated voltage output.

Abstract: There is described a method (20) of cooling a device generating heat. The method includes (21) monitoring a temperature associated with the device. The method also includes (25) automatically operating a cooling means at a first rate if the monitored temperature rises above a first temperature threshold. The method also includes (26) automatically operating the cooling means at a second increased rate if the monitored temperature rises above a second temperature threshold. There is also described a system (10) for cooling a device (16) generating heat. The system (10) comprises means (18) for monitoring a temperature associated with the device (10), cooling means (14), and a controller (12) for operating the cooling means (14) at various rates. The controller (12) is arranged to automatically operate the cooling means (14) at a first rate if the temperature rises above a first temperature threshold.

Abstract: A method, apparatus, computer readable medium, and system for synchronising a power source with a three-phase electricity grid for the power source to supply electricity to the electricity grid is disclosed. The method comprises operating a first switching unit to disconnect a power source from an interfacing circuit. The interfacing circuit comprises a DC-to-AC converter arranged between the power source and a three-phase electricity grid for converting a DC voltage received from the power source to a three-phase AC voltage for supplying the electricity grid, an electrical storage unit connected across the DC-to-AC converter, and a resistance which is selectably connectable in parallel with the electrical storage unit across the DC-to-AC converter, operating a second switching unit to connect the electricity grid to the interfacing circuit, wherein the electrical storage unit is electrically coupled to the electricity grid through the DC-to-AC converter.

Abstract: An apparatus for connecting two or more circuit boards, the apparatus comprising: a first circuit board comprising a first surface and a second surface, the second surface having a first conductive pad; a second circuit board comprising a third surface and a fourth surface, the third surface having a second conductive pad; a fixing means configured to engage with the first circuit board and the second circuit board to couple the first circuit board to the second circuit board, wherein, when coupled, the fixing means is electrically isolated from one of the first circuit board and the second circuit board; and an electrically conductive spacer configured to electrically couple the first conductive pad and the second conductive pad.

Abstract: A damage limitation approach comprising determining that a voltage produced by a rectifier circuit is indicative of a fault and consequently controlling a switch operable to bypass a resistive element of a circuit via which the rectifier circuit is supplied.

Abstract: A method and a control system for a multiphase-phase inverter system, the control system comprising an electric current detection circuit and a processor, wherein each phase of an electrical cycle is separated into a plurality of sections, inputs from the electric current detection circuit are received, each input indicating a measured phase current, and a phase current is calculated in each section, wherein the phase current calculation in at least one of the sections is determined from a changing ratio of the value of the phase current calculated from the measured values of the other phase currents in the multiphase system and the measured value of the phase.

Abstract: A method for configuring a drive to control the operation of a pump in a sewage system is disclosed. The method comprises measuring at least one parameter of the sewage system; using the measurement of the at least on parameter to create an algorithm for the drive to control the operation of the pump; and configuring the drive to use the algorithm to control the operation of the pump.

Abstract: An apparatus for detecting an arc on a circuit having a solar panel assembly is arranged to determine that an output of the solar panel assembly is below a threshold value and is therefore indicative of an arc on the circuit.

Abstract: Apparatus for preventing output of an input signal is disclosed. The apparatus comprises a signal control unit comprising a signal buffering unit having an input and an output, the signal buffering unit arranged to receive an input signal and pass the input signal to the output when the signal buffering unit is powered, wherein a negative power supply terminal of the signal buffering unit is arranged to be supplied by a first power source having a voltage. The signal control unit also comprises a boost circuit arranged to boost the voltage of the first power source to a boosted voltage higher than the voltage of the first power source and supply either the voltage of the first power source or the boosted voltage to a positive power supply terminal of the signal buffering unit.

Abstract: A circuit for an electrical load comprises a passive transformer, the secondary of which is connected to power cells for each phase according to the transformer tappings. Each power cell comprises a low cost but efficient power factor correction circuit to produce lower harmonics on the transformer.

Abstract: A ground fault detection circuit comprising a fuse and a fuse detect circuit. The fuse and the fuse detect circuit are arranged to be coupled in parallel between a reference point and a second point of a monitored circuit for which ground faults are to be detected. The fuse detect circuit is further arranged to detect a fuse break indicative of a ground fault condition and disable at least a portion of the monitored circuit.

Abstract: A turn-on drive circuit for a power transistor comprising a first circuit comprising a resistor and capacitor in parallel and a second circuit comprising a resistor, the second circuit being in series in the drive path with the first circuit. A turn-off drive circuit for a power transistor comprising a first circuit comprising a first resistor and a second resistor in series in the drive path of the power resistor and a second circuit comprising a capacitor in parallel with one of the resistors of the first circuit.

Abstract: A voltage measurement is made between two points in a circuit. If the measured voltage exceeds a predetermined amount, a switch is operated to electrically connect the two points.

Abstract: A control module for use within a control network, the control module comprising: interface circuitry for enabling communication with an external device; communication means configured to communicate with the external device over the control network by communication with the interface circuitry; coupling means configured to mechanically couple the control module to an adjacent control module and provide a data connection between the communication means and the adjacent module; and an electrical isolation in the data connection between the communication means and the coupling means.

Abstract: An inverter circuit comprises an inverter which can be configurable for controlling the supply of mains current from a grid to an electric machine in a start-up mode whereby the machine drives the prime mover for initialisation. Thereafter the same inverter is reconfigurable as part of the circuit to supply reactive power to the grid when the machine is running as a generator powered by the prime mover.

Abstract: The present invention relates to a method and tool for assisting alignment of one or more pin headers. In particular, the invention relates to a tool-assisted method of aiding alignment of one or more pin headers placed on a printed circuit board (PCB) prior to soldering, as well as to the tool itself.

Abstract: A desaturation detection circuit for use between the desaturation detection input of an optocoupler and the output of a power switching device, the desaturation detection circuit comprising: a threshold setting element having an input and an output, the input for connection to the output of a power switching device via one or more diode(s), the threshold setting element being arranged to set a threshold voltage at the input at which the threshold setting element will provide an output at the output of the threshold setting element when the input voltage is exceeded, and a detector having an input connected to the output of the threshold setting element and an output connectable to a desaturation detection input of an optocoupler, the detector being arranged to detect an output at the output of the threshold setting element and in response to provide a control signal at the output of the detector for the desaturation detection input to trigger a desaturation routine in the optocoupler.