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Wind generators have attracted a lot of attention in the realm of renewable energy systems, but they are vulnerable to harsh environmental conditions and grid faults. The influence of the manta ray foraging optimizer (MRFO) on the dynamic performance of the two commonly used variable speed wind generators (VSWGs), called the permanent magnet synchronous generator (PMSG) and doubly-fed induction generator (DFIG), is investigated in this research article. The PMSG and DFIG were exposed to identical wind speed changes depending on their wind turbine characteristics, as well as a dangerous three-phase fault, to evaluate the durability of MRFO-based wind side controllers. To protect VSWGs from hazardous gusts and obtain the optimum power from incoming wind speeds, we utilized a pitch angle controller and optimal torque controller, respectively, in our study. During faults, the commonly utilized industrial approach (crowbar system) was exclusively employed to aid the studied VSWGs in achieving fault ride-through (FRT) capability and control of the DC link voltage. Furthermore, an MRFO-based PI controller was used to develop a crowbar system. The modeling of PMSG, DFIG, and MRFO was performed using the MATLAB/Simulink toolbox. We compared performances of PMSG and DFIG in reference tracking and resilience against changes in system parameters under regular and irregular circumstances. The effectiveness and reliability of the optimized controllers in mitigating the adverse impacts of faults and wind gusts were demonstrated by the simulation results. Without considering the exterior circuit of VSWGs or modifying the original architecture, MRFO-PI controllers in the presence of a crowbar system may help cost-effectively alleviate FRT concerns for both studied VSWGs. [ABSTRACT FROM AUTHOR]

This paper assesses the effect of an inter-turn short circuit fault in stator windings of a Permanent Magnet Synchronous generator (PMSG)-based variable speed wind energy conversion system (WECS) connected to the grid by a power converters interface. The objective is to assess the impact of the fault on the WECS performances. This study has two tasks. The first one details a dynamic modeling of different subsystems of the WECS. The mathematical model of the defective PMSG is also set up. The second one presents an appropriate control strategy for the power converters interface. The control of the PMSG-side converter aims to ensure the operation in maximum power point tracking. The grid-side control was also established by controlling the active and reactive powers to ensure the operation in unity power factor and keeping the DC bus voltage stable. The performance of the control design was tested under healthy and faulty conditions. [ABSTRACT FROM AUTHOR]

Grid faults are found to be one of the major issues in renewable energy systems, particularly in wind energy conversion systems (WECS) connected to the grid via back-to-back (BTB) converters. Under such faulty grid conditions, the system requires an effective regulation of the active (P) and reactive (Q) power to accomplish low voltage ride through (LVRT) operation in accordance with the grid codes. In this paper, an improved finite-control-set model predictive control (FCS-MPC) scheme is proposed for a PMSG based WECS to achieve LVRT ability under symmetrical and asymmetrical grid faults, including mitigation of DC-link voltage fluctuation. With proposed predictive control, optimized switching states for cost function minimization with weighing factor (WF) selection guidelines are established for robust BTB converter control and reduced cross-coupling amid P and Q during transient conditions. Besides, grid voltage support is provided by grid side inverter control to inject reactive power during voltage dips. The effectiveness of the FCS-MPC method is compared with the conventional proportional-integral (PI) controller in case of symmetrical and asymmetrical grid faults. The simulation and experimental results endorse the superiority of the developed FCS-MPC scheme to diminish the fault effect quickly with lower overshoot and better damping performance than the traditional controller. [ABSTRACT FROM AUTHOR]

The hybrid renewable energy harvesting and grid integration system has been proposed and validated in this work. The proposed system uses a Wind Energy Conversion System (WECS) and a Solar Photo Voltaic Energy Conversion System (SPVECS). The WECS uses Permanent Magnet Synchronous Generator (PMSG) driven by a wind turbine. The variable frequency and variable voltage output of PMSG is rectified by Diode Bridge Rectifier (DBR) and stepped up by Super Lift Luo Converter (SLLC 1), and finally, the harvested wind energy is delivered to the Direct Current (DC) link of a Distributed Static Synchronous Compensator (DSTATCOM). Further, SPV energy is harvested by using PV modules and voltage is stepped up by another SLLC (SSLC 2), and the harvested PV energy is brought to the DC link of DSTATCOM. The DSTATCOM extends real and reactive power support to the load. The various subsystems of the proposed system have been modelled in Matrix Laboratory (MATLAB) Simulink environment and analyzed their performance. [ABSTRACT FROM AUTHOR]

A unified active power control scheme is devised for the grid-integrated permanent magnet synchronous generator-based wind power system (WPS) to follow the Indian electricity grid code requirements. The objective of this paper is to propose control schemes to ensure the continuous integration of WPS into the grid even during a higher percentage of voltage dip. In this context, primarily a constructive reactive power reference is formulated to raise and equalize the point of common coupling (PCC) potential during symmetrical and asymmetrical faults, respectively. A simple active power reference is also proposed to inject a consistent percentage of generated power even during faults without violating system ratings. Eventually, the efficacy of the proposed scheme is demonstrated in terms of PCC voltage enhancement, DC-link potential, grid real, and reactive power oscillation minimization using the PSCAD/ EMTDC software. [ABSTRACT FROM AUTHOR]

The paper introduces a comprehensive dynamic analysis for a renewable energy based water pumping system. The complete system components are described in details. The components include a wind turbine power system, a permanent magnet synchronous generator (PMSG), a water pumping system and a battery. The storage system is used to enhance the power delivery under weak wind production which consequently enhances the system reliability. Considering the PMSG as the fundamental power unit in the system, a new predictive control procedure is presented to enhance the PMSG performance. To validate the effectiveness of the proposed control scheme, a detailed comparison is accomplished between the designed controller and other three traditional controllers to evaluate the most effective in between. A power management scheme is constructed to manage the power flow and ensuring a sufficient power delivery to the pumping system. The obtained results are presented and analyzed in details to compare between the dynamics of the four predictive controllers used to manage the generator operation. The results report that the formulated control scheme has the best performance in terms of the reduced fluctuations, low calculation capacity, structure simplicity and low currents THD. The obtained results also approve the validness of the designed power management strategy in balancing the power flow and stabilizing the DC bus voltage as well.

The growing tendency of wind energy technology usage has induced researchers to seek more studies on the improvement of wind energy harvesting systems with highly reliable power injected into the electric grid. The amount of extracted wind energy by a wind turbine depends on the accuracy of the maximum power point tracking (MPPT) algorithm associated with the control scheme of the wind energy conversion system (WECS). This paper aims to present a novel development of MPPT algorithm based on parabolic prediction techniques (PPT) for variable speed wind turbines (VSWT) so as to achieve maximum wind power extraction and efficiency enhancement. The developed PPT-MPPT algorithm uses parabolic convex functions to estimate the parabola wind turbine output curve and locate the maximum power point on that curve. Simultaneously the algorithm establishes a systematic procedure for adjusting the concavity and the optimal part of the estimated parabola curve to make sure that the proposed technique is in continuous convergence. The feasibility of the developed PPT-MPPT algorithm has been validated under rapid and random changing wind speed profiles via the MATLAB/Simulink environment. The performance of the proposed PPT-MMPT algorithm is evaluated by comparing the simulation finding to those obtained using the benchmark perturb and observe(P&O) algorithms. The simulation outcomes affirm that the proposed PPT-MPPT algorithm outperformed the other algorithms in terms of tracking efficiency and extracted power which can be regarded as an efficacious manner to improve the VSWT system.

Investigations were carried out in a commercial farm from Beba Veche, western Romania, on a number of 80 yearling ewes of 17-18 months of age from the native Tsigai. First group (V1), numbering 40 ewes received during out of season breeding (30.05.2011) a dose of 18 mg subcutaneous melatonin implants (Melovin®), while the second group (V2) consisting out of 40 ewes were treated with subcutaneous melatonin implants + 30 mg FGA (Syncro-Part pessaries) + 500 IU PMSG. Control group was represented by 40 intact females. Ewes were put to ram in 7th of July 2011. Researches shown that in ewes treated with melatonin, 30 mg FGA + 500 IU PMSG (V2) the conception rate was of 82.1%, with a prolificacy of 150%, and a weaning rate of 1.2 lamb/ewe. In V1 group, the weaning rate was of 0.9 lambs/ treated ewe, with significantly lower production costs. Ewes from the control group produced a lamb crop of 0.42 lambs/ewe, significantly less (p≤0.05) comparing to V1 and V2 experimental groups. It was concluded that in Tsigai breed, although the V2 group performed better (producing 48 lambs) compared to V1 group (36 lambs), the difference of 12 lambs does cover additional production costs, therefore the use of melatonin implants alone should be recommended.

Over the past decade, wind power generation (WPG) has focused on energy generation, and much research is being done on renewable energy (RE), especially wind energy (WE). WE guarantee environmentally friendly power generation and help to meet national energy needs due to the declining trend of renewable resources. In this article, various Maximum Power Point Tracking (MPPT) techniques proposed for wind energy conversion system (WECS) modeling control management strategies and efficient wind power generation (WPG) from available sources have been discussed. In addition, a comparative survey of various familiar soft methods is accorded for an easy power system with the wind. At last, a cost‐effective investigation arrived for MPPT techniques found on (a) Saving of energy, (b) period of profit, (c) generated income, (d) cost, (e) capacity utilization aspect, and (f) solidity.

This study aimed to evaluate the effect of mixed feed sorghum-Indigofera on Garut ewes reproductive performance stimulated with Pregnant Mare Serum Gonadotropin (PMSG) hormone. Twenty-eight multiparous Garut ewes were grouped based on feed type (local forage (LF) vs. mixed feed sorghum-Indigofera (SI)), for a 30-day acclimatization period with a completely randomized design. Following acclimatization, all animals were synchronized with PGF2α (i.m.) twice, 11 days apart. Half the population of each group was stimulated with 500 IU PMSG after the second injection. Estrous characteristics were observed for seven days, followed by natural mating. Pregnancy status and the number of fetuses were detected 30 days after mating using ultrasound (USG), and reproductive efficiency was evaluated after parturition. Data during acclimatization were analyzed using a two-sample t-test, while the reproductive performances used a General Linear Model (GLM). Estrous characteristics showed no interaction (p>0.05) between feed types and PMSG stimulation. The onset of estrous in the SI treatment occurred 9.33 hours faster (p0.05), with the pregnancy rate ranging 42.85%-100%. Interestingly, the SI group treated with or without PMSG had a larger litter size (1.43-4.50) compared to the LF group (1.25–1.33). It is concluded that feeding with SI had improved reproductive success, with the highest number of ewes giving birth. Additionally, the ewes fed SI with PMSG had the largest litter size.

Wind Energy Conversion Systems (WECS) are extensively used for connecting directly to grid sources. Permanent magnet synchronous generator (PMSG) based WECS is coupled to both grid and machine through converters. PMSG usually associated rectifiers with converters and voltage source converters at machine side. In this work, PMSG associated rectifiers with converters are considered for analysis of grid stability. The proposed work used Particle Swarm Optimization (PSO) based optimization methods for extraction of maximum power within boundary condition in WECS operation using PMSG. This hightech optimization has MPPT controller for pitch angle controller (PAC) combines with PSO optimized controllers for converter and grid power converters. PSO produces noteworthy optimum coefficients ensuring competent MPPT operation in PAC. Extensive simulation work has been carried out with power converter for current controller of rotor and grid side current controller in MATLAB Simulink environment to assess the proposed system performance in terms output voltage, output current, maximum power extraction. Energy and efficiency of the system when the PMSG based WECS energy injected into the electric grid. To prove the efficiency of the proposed method, the performances have been compared with and Bacteria foraging Algorithm (BFOA). Subsequently, it is evident that proposed PSO based method subsidizes maximum efficiency of MPPT controller by extracting maximum power compared to other conventional techniques. [ABSTRACT FROM AUTHOR]

This paper proposes performance improvement of hydraulic turbine generation system (HTGS) using a subdivided finite set model predictive current control (SFS-MPCC). Recently, the differential pressure control valve (DPCV) is replaced by HTGS because of the frequent breakdown in DPCV caused by cavitation in the district heating systems. The HTGS consists of the hydraulic turbine, permanent magnet synchronous generator (PMSG), back-to-back (BTB) converter, and three-phase grid. Especially, BTB converter is composed of a generator-side inverter, DC-link capacitor, and grid-side inverter. In the generator-side inverter, a model predictive current control (MPCC) has been widely used because of its many advantages, such as robustness from parameter variation, fast dynamic response, and unnecessariness of gain tuning. The conventional MPCC uses only eight voltage vectors; thus, it makes a large current ripple, which is directly related to torque ripple. Therefore, to reduce the current and torque ripple, SFS-MPCC, which uses subdivided voltage vectors is proposed. An additional algorithm to reduce the calculation time is proposed because the subdivided voltage vectors increase the calculation time excessively. The effectiveness of the proposed SFS-MPCC is demonstrated by simulation and experimental results. [ABSTRACT FROM AUTHOR]

The impact on the stability of power systems is rising as the penetration level of renewable energy with sporadic natures rises rapidly on the grid. However, the impact of different types of renewable energy sources (wind, solar) and their combination on system stability varies even with the same penetration level. This paper concentrates mainly on the stability analysis of multi-machine systems connected to various types of renewable energy sources. The study presents a simple and novel control technique named automatic reactive power support (ARS) for both single and combinations of renewable sources by injecting the available reactive power into the system during fault through converters to enhance system stability. The permanent magnet synchronous generator (PMSG) and doubly fed induction generator (DFIG) are both considered as wind generators in this paper for comparison. In addition, transient stability enhancement is carried out by improving critical clearing time of a three-phase fault in the power system. With the creation of a 3-phase fault at various buses, stability analysis is carried out on the 9-bus WSCC test bus system and also on the 68-bus IEEE test system. Comparative analysis of six test case conditions is provided and the considered cases are without renewable source, with DFIG as a wind generator, PMSG as a wind generator, solar PV farm, wind farm with DFIG and solar PV in combination and the combination of wind farm with PMSG and solar PV. Moreover, the improvement in critical clearing time of the system is compared using conventional and proposed controls with all the aforementioned renewable sources. Comparative results show that the proposed control technique improves system stability and also that the combination of renewable energy sources ought to enhance the critical clearing time of system. [ABSTRACT FROM AUTHOR]

The technology of variable speed wind turbines is very promising in renewable power generation. It is imperative for wind turbines to gain control after grid disturbances and contribute to the stability of power grids as part of the requirements of grid codes set by grid operators in operating wind farms. Fault current limiters (FCLs) are capable of augmenting the performance of wind turbines during grid disturbances. In this article, the augmentation of the Doubly Fed Induction Generator (DFIG) and the Permanent Magnet Synchronous Generator (PMSG) wind turbines, which are the two most popular variable speed wind turbines, is presented. The evaluation of both wind turbines was performed considering the Series Dynamic Braking Resistor (SDBR), Bridge Fault Current Limiter (BFCL) and the Capacitive Bridge Fault Current Limiter (CBFCL). The modeling of the FCLs in the wind turbines was derived for steady state and grid disturbances so that their dynamic behavior could be understood. The grid voltage variable was employed as the signal for switching the FCLs in both wind turbines during grid disturbances. Moreover, a scenario with no control using the FCLs was also carried out for both wind turbines. The performance of the FCLs in both wind turbines was analyzed and compared using a severe three-phase to ground fault at their terminals. For effective comparison, the same conditions of operation were used in investigating the performance of the FCLs control strategies in both wind turbines during grid disturbances. The study was conducted using Power System Computer-Aided Design and Electromagnetic Transient including DC (PSCAD/EMTDC) environment. [ABSTRACT FROM AUTHOR]

In this work, the performance of a 500 W permanent magnet synchronous generator was evaluated in MATLAB/Simulink. The Simulink model consists of a wind turbine, a PMSG, and an AC - DC rectifier. The PMSG input parameter were measured and inputted in the Simulink block while the output results were voltages, currents and power respectively. The PMSG was tested at various wind speed. At the rated wind speed of 11m/s, the output power was 443.2 W. [ABSTRACT FROM AUTHOR]

The aim of the present study was to test three protocols for synchronization of estrus and fertility in merino sheep. 3 experimental groups were formed, depending on the duration of progestagen treatment (FGA sponges) and PMSG dose: Group 1 (n = 12) - 12 days + 500 UI. Group 2 (n = 12) - 12 days + 250 UI. Group 3 (n = 11) - 5 days (at the time of sponge placement, sheep were treated with a synthetic analogue of PGF2a) + 500 UI. On the three groups, PMSG was injected at the time of sponge removal. At the 48th hour of sponge removal, the highest number of ewes in the estrus was in the Group 2-12 sheep, while in the others it was 9 (Group 1) and 6 (Group 3). The highest values for fertility and fecundity were obtained in sheep from Group 1-41.66% and 160.0%. [ABSTRACT FROM AUTHOR]

Objective: The aim of this study was to compare the fertility parameters in response to pregnant mare serum gonadotropin (conventional treatment) or gonadotrophin-releasing hormone (alternative treatment) in Romanov sheep subjected to a 7-d short-term protocol during non-breeding season. Materials and Methods: All sheep (n:57) were subjected to short-term synchronization protocol. Intravaginal sponge impregnated with 20 mg fluorogestone acetate was inserted for 7 days and all sheep received 125 µg cloprostenol at sponge removal. Sheep were randomly assigned to receive no additional treatment (CON, n:16), 240 IU pregnant mare serum gonadotropin (PMSG, n:24) at sponge removal or 10 µg buserelin acetate (GnRH, n:17) at 30 h after sponge removal. Natural mating was performed following detection of estrous with fertile eight Romanov rams. Estrous response, pregnancy rate, lambing rate, and litter size were compared among groups. Results: Estrous response and pregnancy rate were 86% and 75.4% in all sheep, respectively. Estrous response was numerically higher about 7% (p>0.05) in treatment groups (PMSG, 87.5%; GnRH, 88.2%) than CON (81.2%). However, pregnancy rate was numerically higher (p>0.05) in PMSG (83.3%) than GnRH (70.6%) and CON (68.7%). Similarly, lambing rate in the PMSG (79.1%) was approximately 15% numerically greater (p>0.05) than in GnRH (64.7%) and CON (62.5%). In addition, litter size in PMSG (2.1) was also numerically higher (p>0.05) than GnRH (1.9) and CON (1.9). Conclusion: The use of GnRH provided similar estrous response compared to use of PMSG in Romanov sheep synchronized with short-term protocol. However, use of PMSG provided numerically higher pregnancy rate, lambing rate, and litter size than use of GnRH. Considering the serious ethical concerns and animal welfare for the production of PMSG, it is necessary to use alternative gonadotropins. Comprehensive studies are needed to compare the fertility parameters between application of PMSG and GnRH in Romanov sheep. [ABSTRACT FROM AUTHOR]

This study aimed to determine the biopotency of pregnant mare serum gonadotropin (PMSG) in stimulating the formation of dominant follicles and the biopotency of human chorionic gonadotropin (hCG) in triggering an increase in the ovulation rate of the natural-estrus donor group and the prostaglandin F2α (PGF2α) induced group using female Aceh cattle (n= 20) which were divided into two treatment groups: the group with natural estrus (A) and the group with PGF2α -induced estrus (B). Each donor group was superovulated using the injection of PMSGhCG (A1, B1) and only PMSG (A2, B2). The observations on total follicles and CL were carried out at D10, D14/D+0 and D21/D+7 using ultrasonography (USG). The results showed that PMSG gave a better superovulatory response to the development of dominant follicles (P0.01) at A1, A2, B1, and B2. The administration of hCG hormone 2000 IU i.m. was not able to increase the rate of ovulation. Total follicles after the addition of hCG were also not significantly different between A1:A2 and B1:B2. Statistically, the number of CL in all donor groups in D21 was not significantly different (P0.05). It concluded, superovulation using PMSG gave the same results to the donor cows with natural estrus and the donor cows with PGF2α-induced estrus. The hCG hormone with a dose of 2000 IU injected i.m. was also not able to increase the ovulation rate of Aceh cattle superovulated with PMSG 2500 IU i.m. ____________________________________________________

There are a variety of hormonal protocols and products on the market, but it is still unclear how they will work on specific field conditions. The efficacy of using different forms of prostaglandin F2α analogues such as dinoprost and cloprostenol in a FGA-based estrus synchronization protocols were compared in sheep. For this purpose, on the basis of a completely randomized design, 60 ewes (Tsigai breed, Rusty variety; 2–4-years old, mean body score of 2.5 ± 0.5) were divided into two estrus synchronization treatment groups, which included: fluorogestone acetate (FGA) sponges for 11 days, with the administration of an intramuscular injection of 5 mg of dinoprost on the 9-day, followed by 300 IU PMSG at the time of sponge withdrawal (FGA-D-PMSG group, n=30), and for the other group, the same synchronization protocol was followed, with the difference that instead of dinoprost, ewes received 75 μg of cloprostenol (FGA-C-PMSG group, n=30). The estrus response rate percentage (%ERR) ranged between 76.66% (FGA-C-PMSG group) and 93.33% (FGA-D-PMSG group). In this study, it is shown that the type of PGF2α (natural or synthetic) can influence the results of a 11-day FGA-PGF2α-PMSG synchronization protocol, in terms of occurrence of estrus behaviour. Additionally, hormonal treatments cost for each protocol was calculated in order to determine the most cost-effective method and whether it can be implemented in small and large-scale sheep farming.

Wind energy conversion system, one of the main components is a Permanent Magnet Synchronous Generator (PMSG). During the past two decades, many types of permanent magnet generators for wind power applications have been the research topic. This study focuses primarily on designing a PMSG to create, simulate, and analyze an internal permanent magnet topology with twelve plots and eight poles. We limit with the simulation was carried out at a rotational speed of 1000rpm, and a type of permanent magnet material, Ceramic 11, SmCo 26/26, and NdFeB 48/11. The result of the analysis is that permanent magnets applied in the design of a generator impact its output power and efficiency. At 15 Ω and 60 Ω loads, SmCo 26/26 and NdFeB 48/11 are the only ones that fulfill the specified requirements in this investigation. The permanent magnet type with the most optimal characteristics is Neodymium Iron Boron 48/11 because it has a high flux density, thus causing the electrical energy generated to be greater than other types of permanent magnets. The 48/11 NdFeB permanent magnet generates the most output power, 2110.86 W when loaded with 15 Ω. The best efficiency of 89.38 percent for the PMSG 12 slot eight poles occurs when the load is 15 on the 48/11 NdFeB permanent magnet. [ABSTRACT FROM AUTHOR]

In view of the recent development and phenomenal growth in the field of electrical/power engineering, various new enhanced and sophisticated power control techniques have emerged which have got the enormous capabilities to produce the desired power in the most efficient and effective manner. This paper presents the permanent magnet synchronous generator (PMSG) connected to the wind turbine to extract the maximum power using the integral sliding mode control technique and artificial neural network (ANN). The real power produced by the generator is directly dependent on the internal characteristic of the wind turbine like TSR (tip speed ratio), Power Coefficient, etc. To extract the maximum power from the wind turbine, it has been depicted that ANN a is more efficient and reliable form than the sliding mode control technique. [ABSTRACT FROM AUTHOR]

During permanent magnet synchronous generator (PMSG) operation, aside from improving the rapid response of torque and reducing the rippling of torque and flux to guarantee the operational reliability, the loss of the PMSG itself cannot be ignored either. Aiming at this problem, an improved model predictive direct torque control (MPDTC) method is proposed, which suppresses the torque ripple and achieves PMSG efficiency optimization. Firstly, based on the conventional MPDTC and the loss model of PMSG, the predicted stator active current is determined, which is utilized for obtaining the predicted torque. Secondly, combined with the generator loss model, the set value of the stator energetic current is obtained; combined with the wind power system maximum power point tracking method, the set value of generator torque is obtained. Thirdly, by converting the torque control error and current control error into a per unit value, the influence of the weight coefficient in the cost function on the control effect is reduced. Finally, the key results verified the effectiveness and superiority of the proposed control scheme by simulation and experiment. [ABSTRACT FROM AUTHOR]

The primary objective of this study is to meet the energy demands of the power consumer through the implementation of Hybrid Renewable Energy System (HRES) with multiple solar panels and wind turbines. As the photovoltaic (PV) power generation is enveloped with multiple advantageous measures like low maintenance, environmental-friendliness and fuel-efficient, it is significantly preferred in this study. However, the low power conversion quality of PV weakens the overall system and so the DC-DC improved SEPIC converter with magnetic coupling is employed to achieve maximum DC output voltage. In addition, the Adaptive Neuro Fuzzy Inference System (ANFIS) is implemented in this work totrack the maximum power from PV and to maximize the energy efficiency in an optimal manner. The MATLAB Simulink is used to validate the present study with optimal outcomes and the obtained results prove that the present approach delivers lesser THD of 1.00%, which in turn efficiently enhances the overall performance of the system. Thus, the research findings of this system are well suited to be applied as the solution for rectifying the issues in the DC link voltage control and grid compensation or synchronization. [ABSTRACT FROM AUTHOR]

The supply of purified water in marine and domestic applications, especially in remote areas regarding fossil fuels environmental pollutants, makes it hard to use conventional energy sources. Therefore, the present research seeks to construct a water purification system by using reverse osmosis technology supplied by a novel wind turbine driven with a permanent magnet synchronous generator. To reach this goal, an efficient high torque wind turbine was designed with new butterfly blades in which the lift and drag forces were determined along with creating twisting angles in blades. The blades were initially designed in SolidWorks software. Then, the computational fluid dynamics principles were simulated in the COMSOL5.2a environment by utilizing the k-ω pattern and multi-reference coordinate axis method. A laboratory prototype was implemented to verify the theoretical calculations, simulation analysis, and validity of the wind turbine. To ensure the sufficient capability of the system in worse situations, the performance of the turbine system at a low wind speed of 4 m/s was evaluated. The results showed that a maximum power factor of 0.29 was obtained, making the micro-turbine appropriate for both marine and domestic sweetener systems. [ABSTRACT FROM AUTHOR]

This study aimed to induce estrus by using Human Menopausal Gonadotrophin (HMG) in Iraqi Awassi Ewes and comparison its action with Pregnant Mare Serum Gonadotrophin (PMSG). The study was carried out between first of June 2018(non or earlier-breeding season) until all ewes lambing in the middle of November 2018. Sixty Iraqi Awassi ewes aged 2-4 years old and weight 35-45 kg were used in this study. Ewes were divided randomly into three groups, (20 ewes per each). All ewes comprised of intra-vaginal sponge impregnated by progesterone for 12 days. Control ewes (C) were injected intramuscularly with 2ml of sterile saline solution, HMG treatment group (HMG) were injected intramuscularly with 300 IU of HMG hormone while PMSG treatment Group (PMSG) were injected intramuscularly with 500 IU of PMSG at the same day of sponge removal. Estrus response percentages were 40% (8/20), 85% (17/20), 90% (18/20) in control (which significantly change P

Abstract Globally abundant wave energy for power generation attracts ever increasing attention. Because of non-linear dynamics and potential uncertainties in ocean energy conversion systems, generation productivity needs to be increased by applying robust control algorithms. This paper focuses on control strategies for a small ocean energy conversion system based on a direct driven permanent magnet synchronous generator (PMSG). It evaluates the performance of two kinds of control strategies, i.e., traditional field-oriented control (FOC) and robust adaptive control. The proposed adaptive control successfully achieves maximum velocity and stable power production, with reduced speed tracking error and system response time. The adaptive control also guarantees global system stability and its superiority over FOC by using a non-linear back-stepping control technique offering a better optimization solution. The robustness of the ocean energy conversion system is further enhanced by investigating the Lyapunov method and the use of a DC-DC boost converter. To overcome system complexity, turbine-generator based power take-off (PTO) is considered. A Matlab/Simulink study verifies the advantages of a non-linear control strategy for an Oscillating Water Column (OWC) based power generation system.