RLC circuit

About: RLC circuit is a research topic. Over the lifetime, 14490 publications have been published within this topic receiving 142697 citations.

Impedance matching circuit and antenna apparatus using the same

Abstract: One matching circuit ( 8 - 2 ) comprises a transmission line ( 6 b ) of a predetermined electrical length and a parallel resonance circuit ( 5 ) connected in parallel with the transmission line. The resonance circuit has a resonant frequency f 2 and a predetermined susceptance at a frequency f 1 lower than the frequency f 2 . ANother matching circuit ( 8 - 1 ) comprises a transmission line ( 6 a ) of a predetermined electrical length and a capacitor element (b 3 a ) connected in series with the transmission line between an input terminal ( 2 ) of an antenna ( 1 ) and the matching circuit ( 8 - 2 ) so that the input impedence of the antenna at the frequency f 2 may match the characteristic impedance of an external circuit ( 10 ).

Non-Autonomous Second-Order Memristive Chaotic Circuit

Abstract: A non-autonomous second-order memristive chaotic circuit is considered in this paper, which is comparatively simple, only consisting of a memristor, a capacitor, a resistor, and a sinusoidal voltage source. Based on the descriptive equation of the memristive circuit, the dynamical behaviors are investigated by theoretical analyses and numerical simulations. It is noted that the number of AC equilibrium points changes with the evolution of the time and the circuit exhibits striking dynamical features, including period, chaos, forward period-doubling, reverse period-doubling, tangent bifurcation, and crisis scenarios. Furthermore, a hardware circuit is set up by off-the-shelf discrete components, where hardware experiments are performed to verify the numerical results. The most significant feature of the proposed memristive circuit is the inductor-free realization with simplified topology, which makes the circuit much simpler and more intuitive in physical realization.

Coupled Inductor-Based Zero Current Switching Hybrid DC Circuit Breaker Topologies

Abstract: This paper proposes a coupled inductor-based hybrid dc circuit breaker topology with zero current switching for fast fault interruption in dc systems. A series resonant circuit comprising of the secondary winding of a two-winding coupled inductor and a charged capacitor (commutation capacitor) is switched on during fault to inject a counter-current pulse, and, consequently, force a zero crossing of fault current. Proposed solution facilitates arcless breaking for a mechanical circuit breaker due to zero current turn- off . The proposed circuit breaker exhibits fast fault response ( $\sim$ 30 $\mu$ s), and the response time is programmable based on the design of the coupled inductor and commutation capacitor. Furthermore, presented solution mitigates the requirement of energy-absorbing elements for demagnetizing the dc network following fault interruption, in contrast to conventional dc breakers. The paper also presents two modified circuit-breaker topologies to achieve unipolar voltage profile on the capacitor, which will enable the use of electrolytic capacitors for commutation so that the capacitor stack size is reduced in high-voltage applications. Detailed analysis and design equations are presented to explain the operation of the proposed topologies. Functionality of the proposed circuit breakers is verified through simulation, and experimental results are based on two laboratory prototypes.

Filter having an electromagnetically tunable transmission zero

Abstract: A transmission line filter comprises four resonators (100, 200, 300, 400), and transmission zeroes can be added to the transfer function of the filter using a known phasing coupling technique using a transmission line (53, 54) coupled between two resonators. The location of the transmission zeroes can be varied using control circuits (A,B). Each control circuit comprises a series coupled inductance (55, 58) and capacitance (56, 59) forming a resonance circuit, the resonance frequency of which can be varied using a variable d.c. voltage (V1, V2). The inductance of each control circuit is arranged adjacent its respective transmission line so that the two are weakly electromagnetically coupled. By supplying the variable voltage to the resonance circuits, normal operation of the phasing coupling is affected, thereby varying the location of the transmission zero. One or more control circuits can be provided for filters having transmission zeroes in their transfer function which need to be varied. The provision of these control circuits allow transmission zeroes to be selected in situ, rather than solely during manufacture.

Electronic ballast-inverter for multiple fluorescent lamps

Abstract: An electronic ballast-inverter for multiple fluorescent lamps employs a push-pull inverter and a series resonant circuit for driving the lamps. The inverter operates at the resonant frequency of the series resonant circuit. Current in the resonant circuit is limited, for low-load conditions, in response to a sensing voltage which is used to lower the frequency of operation of the inverter, to make the load more reactive.