Negative impedance converter

About: Negative impedance converter is a research topic. Over the lifetime, 5801 publications have been published within this topic receiving 87636 citations.

Oscillation effects in IGBT's related to negative capacitance phenomena

Abstract: Insulated gate bipolar transistors (IGBT's) are inherently unstable at high collector voltages due to negative gate capacitance values. We investigate IGBT gate voltage oscillations by experiment and through computer simulation. In addition, we show that under certain gate circuit conditions, gate voltage oscillations can lead to already observed collector current imbalance effects.

Fuel cell voltage generator

Abstract: The invention relates to a voltage generator including a fuel cell, a d.c. converter and a storage battery, the input terminals of the d.c. converter being connected to the fuel cell terminals and the output terminals of the d.c. converter being connected on the voltage generator terminals in parallel with those of the battery. A microprocessor regulates the maximum intensity value of the current going through the d.c. converter responsive to the voltage measured at the terminals of the fuel cell in order to maintain the voltage near a preset reference value.

Supply circuit with ripple compensation

Abstract: A supply circuit (1) comprising an inductor (2) coupled to switching means (7) and comprising a capacitor (4) is provided with an impedance (3) located between the inductor (2) and the capacitor (4) , with a current injector (5) and with a feedback loop comprising a converter (6) for controlling the current injector (5) for compensating a ripple in an output voltage across the capacitor (4) . The impedance (3) allows injection of acompensating current at a location different from an output location. This increases a number of possible detections of ripples in the output voltage and allows a ripple in an output voltage to be detected even in case of loads introducing much noise across the capacitor (4) . The converter (6) detects a detection signal via the impedance (3) by measuring a voltage across the impedance (3) or across a serial circuit comprising the impedance (3) and the capacitor (4) . The impedance (3) comprises a resistor or a further inductor.

Bandgap voltage reference based temperature compensation circuit

Abstract: A voltage-to-current converter for use with a bandgap voltage reference circuit for providing a correction current to compensate for the adverse effects of temperature. In one specific embodiment, the voltage-to-current converter is used to provide output voltage curvature correction to the resident bandgap voltage reference circuit.

Analysis of Parallel-Connected Asymmetrical Soft-Switching Converter

Abstract: A new half-bridge converter with two current-doubler rectifiers is proposed. Two transformers are used in the proposed converter. The primary windings of two transformers are connected in series to reduce the voltage stress across the magnetizing inductor, since each magnetizing inductor voltage is equal to one half of the input voltage. Two current-doubler rectifiers at the secondary sides are connected in parallel to reduce the current stress of secondary winding since the secondary winding current is less than one half of the load current. The asymmetrical pulsewidth-modulation technique is used in the proposed converter to regulate the direct current output voltage. The transformer leakage inductance and the output capacitance of switching switches are resonant during the transition interval between two switches in order to achieve zero voltage switching. The operation principle and design considerations of the proposed converter are provided. Experimental results for a 100-W (5 V/20 A) prototype are presented to verify the theoretical analysis and circuit performance