Application Of Relay Feedback Method For Sliding Mode Control On Buck Converter System

Abstract — The Power Electronic Converters (PEC) system is used in the modeling of switching power converters that have various control methodologies including linear control and non-linear control. One of the PEC systems is the Buck Converter which has the main task of controlling the output voltage / load. Buck Converter has the main problem in switching control. Switch control on Buck Converter uses high frequency which can damage components and MOSFET switch on Buck Converter. The voltage regulation of a DC - DC switching converter based on Pulse Width Modulation (PWM) that uses frequency domain control techniques and uses a small average converter signal model. The switching process that uses high frequency produces chattering which results in instability in the system. This paper presents modified sliding mode controller by testing the Relay Feedback control system in the application of Sliding Mode Control (SMC) to improve the performance of the Buck Converter control response. An analysis and simulation by schematic diagram of relay feedback was performed in this work. The purpose is to find the best control parameter by design of relay feedback. Research results shown that proposed work has good performance according to the pre-determined control specifications.   Keywords—buck converter; sliding mode control; pulse width modulation; relay feedbac

Application Of Relay Feedback Method For Sliding Mode Control On Buck Converter System

Abstract — The Power Electronic Converters (PEC) system is used in the modeling of switching power converters that have various control methodologies including linear control and non-linear control. One of the PEC systems is the Buck Converter which has the main task of controlling the output voltage / load. Buck Converter has the main problem in switching control. Switch control on Buck Converter uses high frequency which can damage components and MOSFET switch on Buck Converter. The voltage regulation of a DC - DC switching converter based on Pulse Width Modulation (PWM) that uses frequency domain control techniques and uses a small average converter signal model. The switching process that uses high frequency produces chattering which results in instability in the system. This paper presents modified sliding mode controller by testing the Relay Feedback control system in the application of Sliding Mode Control (SMC) to improve the performance of the Buck Converter control response. An analysis and simulation by schematic diagram of relay feedback was performed in this work. The purpose is to find the best control parameter by design of relay feedback. Research results shown that proposed work has good performance according to the pre-determined control specifications.   Keywords—buck converter; sliding mode control; pulse width modulation; relay feedbac

DESPOSITION METHOD AND DEVICE FOR RAPID ELECTROFORMING

本發明一種高速電鑄沉積方法及裝置，主要係是在該高速電鑄裝置中並聯兩個或兩個以上之電源供應器，使供應電流密度得以提高，俾使該電鑄加工製程，得以達到高速電鑄，如此，其在電鑄過程中，可提高該鍍件母模之陰極效率，有效提高電鑄鍍層之沉積速率，縮短電鑄時間提高加工效率

Fabrication of PLLA/C3S Composite Membrane for the Prevention of Bone Cement Leakage

Kyphoplasty is an important treatment for stabilizing spine fractures due to osteoporosis. However, leakage of polymethyl-methacrylate (PMMA) bone cement during this procedure into the spinal canal has been reported to cause many adverse effects. In this study, we prepared an implantable membrane to serve as a barrier that avoids PMMA cement leakage during kyphoplasty procedures through a hybrid composite made of poly-l-lactic acid (PLLA) and tricalcium silicate (C3S), with the addition of C3S into PLLA matrix, showing enhanced mechanical and anti-degradation properties while keeping good cytocompatibility when compared to PLLA alone and most importantly, when this material design was applied under standardized PMMA cement injection conditions, no posterior wall leakage was observed after the kyphoplasty procedure in pig lumbar vertebral bone models. Testing results assess its effectiveness for clinical practice