This study presents load-frequency-control of a two-area hybrid power system (HPS) incorporating distributed generation, geo-thermal plant, thermal plant and electric-vehicle. Such a complex system with non-linearities leads the power system towards more complexity and accordingly requires a resilient controller to handle such complexity. In this regard, optimal cascaded proportional integral – multistage proportional integral derivative (cascaded PI-MSPID) is explored for developed power system. The efficiency of optimal controller is validated by comparing it with other controllers. The influence of flywheel energy storage on system dynamics is demonstrated. Further, the electric vehicle’s participation in enhancing the system stability is presented. Moreover, the developed system is subjected to an intense load deviation which is a practical data taken from one of the literature. It is demonstrated that responses achieved for proposed cascaded PI-MSPID controller effectively handles the system disturbances, which reflects the strength of proposed cascaded PI-MSPID controller.

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Background:Pregnancy induced hypertension, is the commonest form of life-threatening complications of pregnancy. Pregnancy is described as the only physiological state in which most physiological parameters are abnormal. The anatomical, physiological and biochemical adaptations that take place in a woman during the short span of human pregnancy are profound. Compared with normotensive gravidas, patients with elevated blood pressure have significantly greater maternal and foetal mortality and morbidity. The clinical and laboratory characteristics of hypertension associated with pregnancy are difficult to differentiate from those of hypertension independent of pregnancy. Objective: The objective of this study was to study the prevalence and risk factors of ocular fundus changes among pregnant women with PIH. Materials and Methods: A hospital‐based, cross‐sectional study was carried out among 130 pregnantwomen with PIH. History of symptoms related to the eyes, age, and gravida was recorded. Torchlight was used to examine the anterior segment. One percentage of tropicamide was used to dilate pupils. Direct ophthalmoscope was used to examine the fundus. Blood pressure was measured as per the standard guidelines. Urine sample was taken to look for the presence of proteins in urine. Results: The majority belonged to 18 to 35years (50%) and the majority (54.6%) had gestational age >37 weeks. The majority (75.38%) had gestational hypertension. The prevalence of retinopathy among pregnant women with PIH was 13.7% Grade I retinopathy was most commonly seen in 7.7% of cases followed by Grade II retinopathy in 2.7% of the cases, grade 3 in 1.4% and grade 4 in 0.6%. one patient had exudative retinal detachment. Age was not found to be associated with retinopathy among pregnant women with PIH. The prevalence of retinopathy among women with preeclampsia was 31.7% and in eclampsia was 40 %, compared to only 7.07% in women with gestational hypertension and this difference was statistically significant (P < 0.05). The prevalence of retinopathy among women with blood pressure >150/100 mmHg was 45.4% compared to only 2.6% in women with bloodpressure<150/100 mmHg and this difference was statistically significant (P < 0.05). The prevalence of retinopathy among women with severe proteinuria (+++) was 66.6% compared to 44.5% in women with moderate proteinuria (++), 22.7% among women with mild proteinuria (+) and only 5.5% in women without proteinuria. These differences were statistically significant (P < 0.05) Conclusion: The prevalence of retinopathy among pregnant women with PIH was high. High blood pressure and severe proteinuria and preeclampsia were significantly associated with retinopathy.

The present paper introduces a disturbance-rejection based fractional-order proportional-integral-derivative (DR-foPID) controller as optimal control strategy for performance enhancement of hybrid power system (HPS). The two-area HPS is equipped with various generation sources in the form of solar-thermal-system (STS), conventional thermal, wind-turbine-system (WTS) and geo-thermal power plants establishing a coordinated system frequency and tie-line power control. In addition, electric vehicles (EVs) are integrated with the HPS to check its effect on dynamic characteristics. The controller gains are optimized using an effective bio-geography based krill herd (BBKH) optimization technique to achieve the required performance of the HPS. This study validates the efficacy of the BBKH adjusted DR-foPID controller for efficient operation of system dynamic characteristics. The resilience of DR-foPID controller gains is confirmed by a sensitivity test involving large fluctuations in system load variations from their nominal values. It is also demonstrated that EVs help to increase the performance of HPS. A study involving the power management capability of EVs for improving the system performance is also demonstrated. Moreover, the effect of redox flow battery as energy storage device for system dynamic control are also illustrated. At last, a DR-foPID controller is tested in case study on three-area HPS.