RLC circuit

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

An Inductive Power Transfer System With a High-Q Resonant Tank for Mobile Device Charging

Abstract: Inductive power transfer (IPT), which employs the principle of electromagnetic induction, is widely applied to wireless charging applications. The efficiency of an IPT system is highly dependent on the quality factor (Q) of the power resonant tank. In this paper, a novel design on the structure of the resonant coil is used in the resonant tank to achieve a significantly high Q above 1000 for the IPT system. Compensating capacitors are used in both primary and secondary circuits to align the resonant frequencies in order for the system resonant status to be maintained by a frequency tracking circuit. The experimental results show that with a primary coil Q of 1200, the proposed IPT system allows power to be transferred at a maximum air gap distance to coil diameter ratio of 1.46 for a highest efficiency of 87% at the resonant frequency of 106 kHz.

Non-contact type ic card system

Abstract: PROBLEM TO BE SOLVED: To maximize the power transmission efficiency from a reader or writer device to a proximity wireless card, by setting the respective Q values of a resonance circuit of the reader or writer device and the resonance circuit of an IC card using the Q of the whole communication route. SOLUTION: A reader and/or writer unit 1 constitutes a resonance circuit using a capacitor 104, an antenna drive impedance 120 and an R/W antenna coil 101. A wireless card 2 constitutes a resonance circuit using a card antenna coil 201, a capacitor, and a resistor 220. In such a system, the antenna drive impedance 120 is set so as to maximize the reception efficiency at the proximity wireless card 2 in the target communication distance, and the respective Qs of the resonance circuits are set so as to obtain the necessary bandwidth to secure the sufficient signal level to the target communication speed.

RLC window size reconfiguration

Abstract: A telecommunications device comprises a transceiver (33); a radio link control entity (50); and, a radio link control (RLC) buffer memory (150). The transceiver (33) which enables the device to communicate over an air interface (32). The radio link control entity (50) forms uplink RLC protocol data units (PDUs) for transmission over the air interface (32) and receives downlink RLC protocol data units (PDUs) over the air interface (32). The radio link control (RLC) buffer memory (150) is configured to include a transmitter buffer for storing the uplink RLC protocol data units (PDUs) and a receiver buffer for storing the downlink RLC protocol data units (PDUs). The radio link control entity includes RLC reconfiguration logic means (200) which reconfigures at least one of a size of a transmitter buffer window and a size of a receiver buffer window. In performing the reconfiguration, the RLC reconfiguration logic means implements a strategy for handling at least one of (1) downlink RLC protocol data units (PDUs) which are outside a new receiver buffer window; and (2) uplink RLC protocol data units (PDUs) which are either outside a new transmitter window or whose receipt by the radio access network has not been positively acknowledged.

A Robust One-Cycle Controlled Full-Bridge Series-Parallel Resonant Inverter for a High-Frequency AC (HFAC) Distribution System

Abstract: Resonant inverters are connected to a high-frequency AC (HFAC) bus, where power is delivered to different locations for points-of-use power management. Such a power distribution system subjects to more perturbations and load uncertainties than inverters operating with single load. A novel voltage control method is proposed in this paper for a high-frequency full-bridge resonant inverter with series-parallel resonant tank. A modified one-cycle controlled phase-shift modulation is proposed to effectively compensate the input line variations. The uncertainty model of the high frequency resonant inverter is developed and analyzed with the resonant circuit component tolerance, input line and load variations taken into design considerations. The voltage feedback controller is designed based on the Hinfin robust control theory and is implemented with analog discrete devices. The proposed control scheme has the advantages of fast response for both input line and load perturbations. It also ensures a wide range of system stability and guarantees robustness of the power converter. Both simulations and experimental results are provided to verify with the theoretical analysis through an experimental prototype of a full-bridge resonant inverter with an output power of 150-W operating at 1 MHz and an output voltage of 28 V (rms).

Method for regulating and/or controlling a welding current source with a resonance circuit

Abstract: The invention relates to a method for regulating a welding current source (2) with a resonance circuit (27). According to said method, a bridge circuit (28) is driven through a control device (4). A consumer, especially a welding process, is supplied with energy from an energy source (29) through said bridge circuit (28). Said predetermined switching states (S1 to S6) are stored for driving the individual switching elements (32 to 35) of the bridge circuit (28). When the control device is in its normal operating mode, the bridge circuit (28) is driven according to the switching states (S1 to S4) in succession. In the event of a change in resistance on the consumer side, the control device (5) executes a special operating mode with the resonance frequency of the resonance circuit (27) and drives the bridge circuit (28) according to the switching state provided for the special operating mode.