Abstract: The present invention relates to an electrical system comprising at least one magnetic cell connected to an external grid system and comprising a filtering cell having a capacitor X (CDM1, CDM2, CDM3) and a capacitor Y (CY). Said electrical system comprises an array of switches, connected up-circuit of the capacitors X (CDM1, CDM2, CDM3) and Y (CY) of said filtering cell, said array of switches being configured such that: in a single-phase operating mode, the series-connected switches (S2, S3) on the unpowered phases (B, C) are open, and the switches (S1, S4) connected between the first phase (A) and the other phases (B, C) are closed; in a multi-phase operating mode, the series-connected switches (S2, S3) are closed and the switches (S1, S4) connected between the first phase (A) and the other phases (B, C) are open.

Abstract: An electric power converter with a control device that comprises a processing unit receives control signals and sends modulated signals to inverter stages of the electric power converter. The control device also controls a common stage of the electronic power converter, which is connected between power lines and a common neutral connection. The signals to the common stage are outputted based on inputs from a modulation signal and a reference voltage signal.

Abstract: A metering device includes a standard AC energy meter, and a conversion circuit. The conversion circuit measures the voltages and currents of an installation incompatible with the functional characteristics of the meter. The conversion circuit supplies the meter with AC voltages and currents of values in compliance with the specifications of the meter. The total power supplied to the meter is proportional, except for a known scale factor, to the total power measured on the power system. This device is applied to measuring electrical energy on DC power systems and on AC power systems of a frequency or form incompatible with standard electrical energy meters.

Abstract: The system comprises a central module supplying a distribution network, for example formed by a bus, with permanent DC power. Terminal modules, located near the loads, convert the DC power distributed by the distribution network into DC or AC electrical power adapted to the requirements of each load. A communication bus enables data communication between the various modules.

Abstract: Failure of one or more battery cells, for example of an inverter battery bank, is detected by monitoring the second derivative of the curve U(t) representative of the voltage U at the terminals of the battery in the course of discharge. If the second derivative is positive, this is significant of a failure.

Abstract: The backup time of the battery is obtained by estimation, in iterative manner, of discharging of the battery during successive estimated time intervals. During each of the estimated time intervals, an estimated discharging current in terms of the actual discharge power, an estimated voltage, and an estimated state of charge are computed in accordance with a mathematical model equivalent to the battery. The backup time of the battery is equal to the sum of the estimated time intervals necessary for the estimated voltage to reach a preset threshold. The process enables ageing of the battery to be taken into account and an alarm to be provided when the lifetime of the battery becomes too short.

Abstract: A device connects an external electrical power supply source to an aircraft on the ground to temporarily replace its auxiliary power units. During the overlap period of the two switches used in the aircraft to achieve this transfer, an impedance, preferably a resistance much greater than the internal impedance of the external source is connected in series on the external line. As soon as switching to the external source has been completed, measurement of a sudden drop in the external voltage brings about closing of a static switch which short-circuits the resistance.

Abstract: An auxiliary generator supplies a sinusoidal voltage of fixed amplitude adjusted in phase to the mains supply voltage. A comparator, followed by a threshold circuit and a bistable switch, enables a static contactor to be opened almost instantaneously when the difference between the voltages of the mains supply and of the generator exceeds a certain preset value. Power is then supplied by an auxiliary back-up power supply.

Abstract: A first control loop enables the inverter to be made to operate as a current generator when it recharges the batteries of a back-up power supply. Two other control loops enable the inverter to compensate on the one hand the harmonics, and on for other hand for the reactive part of the current absorbed by the load, when the inverter is on stand-by.

Abstract: The control and monitoring data transmission conductors between the control board and the transistor conversion circuit are formed into a flexible flat cable whose intermediate part is wound on a single magnetic circuit to constitute a common mode inductance designed to compensate the disturbances affecting the printed circuit board due to the potential changes of the semi-conductors generated when switching takes place from the conducting state to the blocking state, and vice-versa.

Abstract: The measuring circuit comprises an integrator to which a signal representative of the current flowing through the primary winding of the output transformer of an inverter is applied. The integrator output signal is reset at the beginning of each period of the A.C. component of said current and is applied to a sample and hold stage whose output signal represents the integrator output signal just before it is reset. An intermediate stage is arranged between the integrator and the sample and hold stage to reduce the influence of load impacts by limiting the maximum possible variation of the output signal during the sampling period.

Abstract: A filter unit for a static converter, notably an inverter, comprises at least one module having four capacitors arranged on a support with a square base in two groups connected in parallel to the power supply terminals of opposite polarities, each group comprising two series-mounted capacitors. The voltage at the mid-points of the two groups is fixed by a voltage divider comprising two balancing resistors, and an auxiliary impedance formed by the intermediate part of the connecting device. The support base is provided with coupling means to enable modular assembly by associating several modules identical on the four sides of the base.

Abstract: A converter comprises a plurality of modules each having a heat-sink unit with a base-plate made of a good heat-conducting metal material, acting as a support for the electronic components, a pair of parallel flanges laterally fixed to the opposite edges of the base-plate, and a rear plate for connection of the draw-in contacts capable of cooperating with the studs of a fixed connecting base. Error prevention means, formed by pins and orifices prevent any module connection error. The draw-in contacts are achieved by tulip-fingers or grips capable of being housed in six holes of the connection plate. The assembly forms a rack which can be actuated by a handle.

Abstract: The protective filter comprises an internal reference plane, electrically insulated from the converter housing and acting as ground plane for the internal elements of the static converter, and filtering capacitors respectively connecting the internal reference plane to the input and output cables of the converter.

Abstract: There is disclosed an alternating current to direct current static converter which includes a three-phase transformer interconnected with two rectifier bridges to produce a twelve-phase connection for direct current output. The twelve-phase connection is provided by coupling input terminals of one of the bridges to corresponding primary input terminals of each of the three phases of the transformer, and coupling input terminals of the other of the bridges to corresponding phase terminals of the secondary of the three-phase transformer. The outputs of the rectifier bridges are then coupled to provide the DC output. The transformer is constructed such that there is a 150 degree phase shift between the primary and secondary voltages of each phase of the three-phase transformer and a 30 degree phase shift between the input voltages to the rectifier bridges.