In this paper, a multi-scroll chaotic system from the improved Chua's system is proposed. Moreover, non-linear dynamics are analyzed including phase-space trajectories, bifurcation diagrams, Poincaré maps and so on. The most important thing is that we discovered phase-space trajectories, bifurcation diagrams and Poincaré maps are unified and closely related, which can describe different aspects of the multi-scroll chaotic system. Furthermore, the corresponding improved module-based circuits are designed for realizing two to four-scroll chaotic attractors, and the experimental results are also obtained, which are consistent with the numerical simulations.
Permanent magnet linear synchronous motors (PMLSM) has the advantages of high speed, high thrust density, high power density, high power factor and high reliability. In order to save permanent magnet (PM) materials and reduce magnetic leakage, a new type of PMLSM with Halbach consequent-pole (HCP) structure is presented, which has great potential for application to the ropeless elevator system. By using extensive finite element analysis (FEA), the electromagnetic properties of the proposed HCP-PMLSM, including magnetic field, back electromagnetic force (back-EMF), thrust force and cogging force are simulated and compared with the consequent pole PMLSM (CP-PMLSM) and surface-mounted pole PMLSM (SP-PMLSM). The comparison results show that the proposed HCP configuration can reduce substantial PM material and increase the air-gap magnetic field effectively. Then, the influence trend of HCP parameters such as pole thickness, pole width ratio, auxiliary PM width and magnetism angle, are studied and analyzed for evaluating the output performance in HCP-PMLSM. On this basis, Response surface method (RSM) is employed to optimize the HCP parameters with the target of maximum average thrust, minimum thrust ripple, and highest PM utilization. Furthermore, a double-sided pole shift method was proposed to significantly suppress the thrust fluctuation of HCP-PMLSM. Lastly, experimental results are provided to verify the investigation.
High step-up dc-dc converter is an essential part in several renewable energy systems. In this paper, a new topology of step-up dc-dc converter based on interleaved structure is proposed. The proposed converter uses three energy storing capacitors to achieve a high voltage gain. Besides the high voltage gain feature, the proposed converter also reduces the voltage stress across the semiconductor switches. This helps in using low rating switching devices which can reduce the overall size and cost of the converter. The operating principle of the proposed converter is discussed in detail and its principle waveforms are analyzed. An experiment is carried out on a 20 V input, 130 V output, and 21 W power prototype of the proposed converter in the laboratory to verify the performance of the proposed converter. An efficiency of 91.3% is achieved at the rated load.
scite is a Brooklyn-based organization that helps researchers better discover and understand research articles through Smart Citations–citations that display the context of the citation and describe whether the article provides supporting or contrasting evidence. scite is used by students and researchers from around the world and is funded in part by the National Science Foundation and the National Institute on Drug Abuse of the National Institutes of Health.