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In this article is used to demonstrate of sliding mode controller (SMC) for a multilevel inverter based distributed static compensator (DSTATCOM)for compensation of current harmonics related power quality issues and dc side capacitor voltage balancing of cascaded H-bridge multilevel inverter (CHBMLI). The nonlinear sliding mode controller is developed for the dc link voltage and current control of CHBMLI based DSTATCOM using feedback linearization method. The use of SMC algorithm for DSTATCOMDC link voltage regulating offers several benefits such as decrease in switching ripple in dc side voltage and the constant DC capacitor voltage during dynamic conditions. The algorithm of SMC is realized on a DSTATCOM based on cascaded H-bridge multilevel inverter feeding three phase loads. The presentation of characteristics of DSTATCOM with the proposed dc link voltage balancing strategy is establish adequate for voltage balancing and elimination of power quality problems like harmonics current. Further, performance of SMC with improved voltage balancing algorithm is compared with PI controller using improved voltage balancing scheme of the DSTATCOM. The performance characteristics are validated with real-time study and SMC with improved voltage balancing scheme exhibits improved transient and steady state response of the DSTATCOM.

In this article reduced switch count-based distributed static compensator (DSTATCOM) is presented. DSTATCOM is a reduced switch count-based multilevel inverter (MLI)-based DSTATCOM that is used to eliminate harmonics in the source current caused by a non-linear load. The reference current estimation is carried out with a sliding mode controller (SMC) based synchronous reference frame (SRF). The estimation of the harmonics real power and reactive power components is used for the subsequent calculation of desired currents of the DSTATCOM. In addition to this, DSTATCOM performance was also tested with an artificial neural fuzzy inference system-based control scheme. The training data is obtained from SMC-based SRF control schemes. The DSTATCOM is modeled with MATLAB/Simulink using Simpower system block sets. The simulation study of DSTATCOM with different control schemes is carried out to examine its harmonics elimination capabilities using MATLAB. The simulation results of the various DSTATCOM control method demonstrate the reduced harmonics current caused by the load. The ANFIS-SRF exhibits better compensation characteristics than the SMC-SRF scheme. The simulated results of DSTATCOM with an ANFIS-SRF scheme give reduced ripple content in the DC side voltage of the capacitor.

This paper presents an efficient and reliable Genetic Algorithm based solution for Selective Harmonic Elimination (SHE) switching pattern. This method eliminates considerable amount of lower order line voltage harmonics in Pulse Width Modulation (PWM) inverter. Determination of pulse pattern for the elimination of some lower order harmonics of a PWM inverter necessitates solving a system of nonlinear transcendental equations. Genetic Algorithm is used to solve nonlinear transcendental equations for PWM-SHE. Many methods are available to eliminate the higher order harmonics and it can be easily removed. But the greatest challenge is to eliminate the lower order harmonics and this is successfully achieved using Genetic Algorithm without using Dual transformer. Simulations using MATLABTM and Powersim with experimental results are carried out to validate the solution. The experimental results show that the harmonics up to 13th were totally eliminated.

Nowadays, the usage of the latest technologies and pure energies like photovoltaic energy, wind energy, and electrical vehicles are increasing in demand to minimise environmental pollution. Hence, to hold this kind of technologies, the distribution systems in the future have to be converted to AC–DC hybrid for considering all kinds of DGs and (DC and AC) of loads. This paper attempts to develop an integration of DG with AC–DC hybrid distribution systems connected with solid state transformer (SST). The main intention of this paper is to make an energy-efficient system, by enhancing the voltage profile, reducing greenhouse gas emissions and reducing real and reactive power losses, when DG with SST is connected to a hybrid distribution system. With these constraints, a multi-objective function is formulated, which is solved by a new improved meta-heuristic algorithm in optimal location and sizing of DG. The new algorithm adopted in this paper is the improved Rider Optimisation Algorithm (ROA) termed as Fitness Rate-based ROA (FR-ROA). The experimental analysis on single and multi-objective functions proves the efficacy of SST in providing an energy-efficient system model. [ABSTRACT FROM AUTHOR]

This paper introduces a novel and comprehensive solution for a water-pump drive system powered by photovoltaic (PV) energy. The system incorporates an open-ended winding induction machine (OWIM) that is compelled by a double-inverters, enabling the functionalities of a three-level inverters while utilizing a lower-value DC-bus voltages. This configuration facilitates an optimum arrangements of solar panels, eliminating the need for large strings and enhancing the performances of the solar systems by enabling a wide operating voltage range. Additionally, the reduced potential ratings of the DC-linking capacitances and switching elements in the scheme leads to cost savings. The proposed controller approach links maximum power point tracking (MPPT) and V/f controllers, ensuring effective utilizations of both the solar modules and the motor. Notably, the controller system only necessitates detecting of solar voltages and current, resulting in a reduced number of sensors, thereby improving system simplicity and cost-effectiveness. This paper presents comprehensive analytical and simulation results, showcasing the system's performance under various environmental conditions.

Setting: Tuberculosis Control Program, Western Australia., Objective: To assess the effectiveness and efficiency of tuberculosis (TB) surveillance in immigrants., Design: Retrospective descriptive analysis of records of immigrants who first registered with the Tuberculosis Program from January 1994 to December 1995, having entered Western Australia on health undertakings (nonlegal contracts signed by those determined during premigration screening to require post-arrival evaluation)., Results: Of 1,344 immigrants on health undertakings for TB in the period, 587 (44%) had findings directly related to TB through pre-migration screening, 69 of whom required treatment for active disease. Another 443 (33%) had chest X-ray changes for which TB could not be excluded. Of the remaining 314 (23%), 172 had poor quality X-rays. Post-arrival assessment and follow-up of the whole group detected four of seven additional cases of active TB, 373 persons (28%) requiring on-going surveillance, 667 (50%) with non-TB conditions and 280 (21%) with normal chest X-rays., Conclusions: Migrant surveillance for TB in Australia is effective in detecting active disease and identifying a high-risk subgroup requiring further evaluation. Efficiency can be improved and high compliance achieved with simple administrative changes. Routine pre-migration Mantoux testing is inappropriate, and its inclusion in post-arrival assessments should be a national policy decision.

Setting: State Tuberculosis Control Programme, Western Australia., Objective: To ascertain baseline information, applicability and efficacy of preventive therapy for tuberculosis (TB) under indirectly supervised treatment in Western Australia., Design: Retrospective analyses of records of persons with TB infection who were prescribed preventive therapy for the period 1993-1996 inclusive, using simple descriptive statistics., Results: Preventive therapy was given to 411 persons after screening for TB due to on-arrival migrant surveillance (269), contact tracing (59), tuberculin surveys (59) and other reasons (24). Six-month isoniazid monotherapy (HMT) was prescribed for 403 and multidrug regimens for the remaining eight. Excepting 34 whose compliance was unknown, varying degrees of treatment non-adherence were found in 90 (24%) of the remaining 369 persons given HMT, including 36 (10%) with under five months of total medication. Minor adverse drug effects occurred in 32 (9%) subjects and contributed to the non-adherence in 23 of these. One person has since developed active TB., Conclusions: Preventive therapy in Western Australia conformed to generally accepted guidelines. Varying degrees of non-adherence to HMT occurred in 24% of persons, but 90% completed adequate therapy under indirect supervision. Non-adherence is significantly related to adverse drug effects.