African vulture optimizer algorithm based vector control induction motor drive system

This study describes a new optimization approach for three-phase induction motor speed drive to minimize the integral square error for speed controller and improve the dynamic speed performance. The new proposed algorithm, African vulture optimizer algorithm (AVOA) optimizes internal controller parameters of a fuzzy like proportional differential (PD) speed controller. The AVOA is notable for its ease of implementation, minimal number of design parameters, high convergence speed, and low computing burden. This study compares fuzzy-like PD speed controllers optimized with AVOA to adaptive fuzzy logic speed regulators, fuzzy-like PD optimized with genetic algorithm (GA), and proportional integral (PI) speed regulators optimized with AVOA to provide speed control for an induction motor drive system. The drive system is simulated using MATLAB/Simulink and laboratory prototype is implemented using DSP-DS1104 board. The results demonstrate that the suggested fuzzy-like PD speed controller optimized with AVOA, with a speed steady state error performance of 0.5% compared to the adaptive fuzzy logic speed regulator’s 0.7%, is the optimum alternative for speed controller. The results clarify the effectiveness of the controllers based on fuzzy like PD speed controller optimized with AVOA for each performance index as it provides lower overshoot, lowers rising time, and high dynamic response

Development and implementation of two-stage boost converter for single-phase inverter without transformer for PV systems

This paper offers a two-stage boost converter for a single-phase inverter without transformer for PV systems. Each stage of the converter is separately controlled by a pulse width modulated signal. A Simulink model of the converter using efficient voltage control topology is developed. The proposed circuit performance characteristics are explained and the obtained simulation results are confirmed through the applied experiments. Moreover, this paper has examined the control circuit of a single-phase inverter that delivers a pure sine wave with an output voltage that has the identical value and frequency as a grid voltage. A microcontroller supported an innovative technology is utilized to come up with a sine wave with fewer harmonics, much less price and an easier outline. A sinusoidal pulse width modulation (SPWM) technique is used by a microcontroller. The developed inverter integrated with the two-stage boost converter has improved the output waveform quality and controlled the dead time as it decreased to 63 µs compared to 180 µs in conventional methods. The system design is reproduced in Proteus and PSIM Software to analyze its operation principle that is confirmed practically

Experimental Validation of Second-Order Adaptive Fuzzy Logic Controller for Grid-Connected DFIG Wind Power Plant

This paper introduces a second-order adaptive fuzzy logic controller (SO-AFLC) to enhance the characteristics of a doubly fed induction generator (DFIG) inside a grid-tied wind power plant (WPP). SO-AFLCs were utilized to maximize the output of the DFIG wind power plant (WPP) and improve dynamic responsiveness with extremely low mean square error. When comparing the mean square error of SO-AFLC with proportional-integral controllers (PI) and adaptive fuzzy logic controllers (AFLC), the reductions are 87.38% and 40.39%, respectively. This controller prevents overshoots and oscillations. DFIG wind power plant is modeled and simulated using Matlab/Simulink package. Under the unit step wind speed profile, SO-AFLC improved the steady-state error in the Cp waveform by 63.25% compared with the PI controller and 13.12% compared with AFLC. DSpace1104 is used to conduct an experimental investigation to validate the simulation results. In addition, realistic data from the wind farm at RAS Ghareb in the Gulf of Suez, Egypt, are used in this study to achieve more realistic results. Compared to those obtained with PI and AFLC, the results obtained using SO-AFLCs showed fast time response, high convergence rate, reduced peak overshoot, less undershoot, and low steady-state error in terms of power coefficient of the turbine, DC link voltage control, and rotor speed tracking. In addition, a wind turbine performance index based on gross system integral absolute error (IAE) is provided. This index is used to illustrate the SO-AFLC methodology’s viability compared to AFLC and PI under the same wind turbine conditions

Efficacy, durability, and safety of intravitreal faricimab with extended dosing up to every 16 weeks in patients with diabetic macular oedema (YOSEMITE and RHINE): two randomised, double-masked, phase 3 trials

Background: To reduce treatment burden and optimise patient outcomes in diabetic macular oedema, we present 1-year results from two phase 3 trials of faricimab, a novel angiopoietin-2 and vascular endothelial growth factor-A bispecific antibody. Methods: YOSEMITE and RHINE were randomised, double-masked, non-inferiority trials across 353 sites worldwide. Adults with vision loss due to centre-involving diabetic macular oedema were randomly assigned (1:1:1) to intravitreal faricimab 6·0 mg every 8 weeks, faricimab 6·0 mg per personalised treatment interval (PTI), or aflibercept 2·0 mg every 8 weeks up to week 100. PTI dosing intervals were extended, maintained, or reduced (every 4 weeks up to every 16 weeks) based on disease activity at active dosing visits. The primary endpoint was mean change in best-corrected visual acuity at 1 year, averaged over weeks 48, 52, and 56. Efficacy analyses included the intention-to-treat population (non-inferiority margin 4 Early Treatment Diabetic Retinopathy Study [ETDRS] letters); safety analyses included patients with at least one dose of study treatment. These trials are registered with ClinicalTrials.gov (YOSEMITE NCT03622580 and RHINE NCT03622593). Findings: 3247 patients were screened for eligibility in YOSEMITE (n=1532) and RHINE (n=1715). After exclusions, 940 patients were enrolled into YOSEMITE between Sept 5, 2018, and Sept 19, 2019, and 951 patients were enrolled into RHINE between Oct 9, 2018, and Sept 20, 2019. These 1891 patients were randomly assigned to faricimab every 8 weeks (YOSEMITE n=315, RHINE n=317), faricimab PTI (n=313, n=319), or aflibercept every 8 weeks (n=312, n=315). Non-inferiority for the primary endpoint was achieved with faricimab every 8 weeks (adjusted mean vs aflibercept every 8 weeks in YOSEMITE 10·7 ETDRS letters [97·52% CI 9·4 to 12·0] vs 10·9 ETDRS letters [9·6 to 12·2], difference −0·2 ETDRS letters [−2·0 to 1·6]; RHINE 11·8 ETDRS letters [10·6 to 13·0] vs 10·3 ETDRS letters [9·1 to 11·4] letters, difference 1·5 ETDRS letters [−0·1 to 3·2]) and faricimab PTI (YOSEMITE 11·6 ETDRS letters [10·3 to 12·9], difference 0·7 ETDRS letters [−1·1 to 2·5]; RHINE 10·8 ETDRS letters [9·6 to 11·9], difference 0·5 ETDRS letters [−1·1 to 2·1]). Incidence of ocular adverse events was comparable between faricimab every 8 weeks (YOSEMITE n=98 [31%], RHINE n=137 [43%]), faricimab PTI (n=106 [34%], n=119 [37%]), and aflibercept every 8 weeks (n=102 [33%], n=113 [36%]). Interpretation: Robust vision gains and anatomical improvements with faricimab were achieved with adjustable dosing up to every 16 weeks, demonstrating the potential for faricimab to extend the durability of treatment for patients with diabetic macular oedema. Funding: F Hoffmann-La Roche