Abstract: Disclosed is a compound with the following formula (I): as well as the use thereof, in particular as a chelating agent of positively charged ions, or as a fluidizing agent for hydraulic compositions. Also disclosed is a hydraulic composition comprising a compound with formula (I), at least one hydraulic binder, at least one aggregate, and water.

Abstract: The control circuit of an electric motor, which has at least one phase supplied with high voltage and has a defined high-voltage zone, is provided with a control for the supply current of the phase with a setpoint-value current, and has devices for measuring the supply current which generate a first analog signal whose value corresponds to the measured current, an electronic control unit being disposed in a low-voltage zone, and having an analog-to-digital converter for converting the first analog signal or another analog signal acting as the first analog signal, into a corresponding digital signal which is supplied to the electronic control unit. The measuring devices are formed by a bleeder resistor, which is disposed in series with the phase, as well as by a differential amplifier whose two inputs, respectively, are connected to two contacts of the bleeder resistor.

Abstract: In a method for controlling three single-phase motors and moving a platform in a direction of the normal, the motors are controlled by one three-phase converter, so that a first motor is operated between a first phase and a second phase of the converter, and a series connection or parallel connection of a second and third motor is operated between a second phase and a third phase of the converter. A platform is adapted to perform this method.

Abstract: A PWM signal for driving power transistors of a half-bridge of a converter is generated with the aid of a digital circuit, in which an internal reference value is compared to the counter content of a counting ramp. In this context, a logic state of the PWM signal depends upon whether the internal reference value is greater than the counter content of the counting ramp. After each comparison between the internal reference value and the counter content, an n-bit long data word dependent on the result of this comparison is output serially as PWM signal, n being greater than or equal to 2. The resolution of the PWM signal is thereby improved by the factor n in comparison to conventional systems, without markedly increasing the circuit expenditure.

Abstract: The control circuit of an electric motor, which has at least one phase supplied with high voltage and has a defined high-voltage zone, is provided with a control for the supply current of the phase with a setpoint-value current, and has devices for measuring the supply current which generate a first analog signal whose value corresponds to the measured current, an electronic control unit being disposed in a low-voltage zone, and having an analog-to-digital converter for converting the first analog signal or another analog signal acting as the first analog signal, into a corresponding digital signal which is supplied to the electronic control unit. The measuring devices are formed by a bleeder resistor, which is disposed in series with the phase, as well as by a differential amplifier whose two inputs, respectively, are connected to two contacts of the bleeder resistor.

Abstract: An electronic circuit includes a linear amplifier unit having a first current feedback loop, assisted by a switched-mode amplification unit having a second current feedback loop. The inputs of the two units are connected so that they receive, at the same time, a current setpoint in an operating mode in order to generate a fixed current across a load connected to the output of the units. The first feedback loop includes a first sensor to measure the current in the load, a first subtractor element to subtract the first measured current from the current setpoint, a first controller connected to the output of the first subtractor element and controlling a linear amplifier, which supplies the first output current to the load. The second feedback loop includes a second current sensor to measure a second current supplied to the load, between a connecting node of two switches connected in series to a supply voltage source and an inductor whose output is connected to the load.

Abstract: In a method for controlling three single-phase motors and moving a platform in a direction of the normal, the motors are controlled by one three-phase converter, so that a first motor is operated between a first phase and a second phase of the converter, and a series connection or parallel connection of a second and third motor is operated between a second phase and a third phase of the converter. A platform is adapted to perform this method.

Abstract: An electronic circuit includes a linear amplifier unit having a first current feedback loop, assisted by a switched-mode amplification unit having a second current feedback loop. The inputs of the two units are connected so that they receive, at the same time, a current setpoint in an operating mode in order to generate a fixed current across a load connected to the output of the units. The first feedback loop includes a first sensor to measure the current in the load, a first subtractor element to subtract the first measured current from the current setpoint, a first controller connected to the output of the first subtractor element and controlling a linear amplifier, which supplies the first output current to the load. The second feedback loop includes a second current sensor to measure a second current supplied to the load, between a connecting node of two switches connected in series to a supply voltage source and an inductor whose output is connected to the load.

Abstract: A PWM signal for driving power transistors of a half-bridge of a converter is generated with the aid of a digital circuit, in which an internal reference value is compared to the counter content of a counting ramp. In this context, a logic state of the PWM signal depends upon whether the internal reference value is greater than the counter content of the counting ramp. After each comparison between the internal reference value and the counter content, an n-bit long data word dependent on the result of this comparison is output serially as PWM signal, n being greater than or equal to 2. The resolution of the PWM signal is thereby improved by the factor n in comparison to conventional systems, without markedly increasing the circuit expenditure.

Abstract: System for actuating a contactor of electronic component for the electric testing of said components, whose movement is generated by an electromechanical transducer and controlled by a control system limiting the pressing force of the contactor on the component to be tested.

Abstract: A device for improving the quality of audio and/or video signals comprises a main electrical circuit comprising an integrated circuit arranged for producing an output pulse signal having a predetermined frequency, and a toroidal inductor having a magnetic core which has a central opening and which is surrounded by a conducting wire, said toroidal inductor being arranged to be powered by said output signal.The device is arranged between a power supply unit and a signal processing unit which is connected by at least a phase- and a neutral conductor to said power supply unit such that said conductors pass through said central opening of said magnetic core, said toroidal inductor creating an alternating magnetic field within its core when it is powered by said output signal, so that said magnetic field induces an electric field which acts on said conductors.