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Reliable, uninterrupted and quality power supply is the key factors for economic growth of any country and become the government's priority. To meet this requirement, the power sector has grown tremendously over last two decades in the areas of generation, transmission, distribution sector. With a total installed capacity of 395 GW(as on 31st January, 2022), India has transformed from a power deficit (peak) - 12.7% in FY 2009-10 to -1.2% in FY 2021-22. Every country throughout the globe has been trying to shift towards the renewable energy (RE) from conventional energy in order to meet the net zero emission target by 2070 in compliance with COP-26 held at Glasgow. In this context, India has set a target of 500 GW RE generation by 2030 and achieved 150 GW RE capacity as on February 2022. This transition of energy sector creates several challenges which need to be addressed for proper integration of RE sources into the grid. In this paper, at first, the background of power sector reform is briefly discussed and the role of each segment (generation, transmission and distribution) in transition of the entire energy sector is also highlighted. The role of Electricity Act 2003 in power sector reform or transition is discussed. Furthermore, various policy issues related to RE and the integration challenges into the grid are also outlined. Moreover, the effect of RE on several power system parameters such as system strength, inertia, rate of change of frequency (ROCOF) etc. are elaborated. In this context, few case studies are highlighted to show the impact of RE integration into the existing grid. Finally, few recommendations are provided to address the RE integration challenges. [ABSTRACT FROM AUTHOR]

In multi-MW three-level neutral point clamped back-to-back (3L-NPC) power converters, power semiconductor devices are considered as most vulnerable components due to its thermo-mechanical fatigue stress. Particularly, rotor side converter (RSC) in doubly fed induction machine (DFIM) experiences high thermal stress during its operation around synchronous speed. It degrades the performance of power converter and reduces the lifetime availability of the drive. In practice, stabilization of temperature fluctuation across each power semiconductor device improves the efficiency and reliability of power converter. With respect to this prime aim, this paper proposes a carrier-based active thermal control method to regulate temperature fluctuation across power semiconductor devices in a multi-MW (5 x 5 MW) 3L-NPC power converters serving to a 250 MW asynchronous hydro-generating unit. To test the proposed active thermal control method, different operating conditions of a 250 MW DFIM hydro-generating unit (to be commissioned in Tehri pumped storage plant, India) are examined in MATLAB/PLECS environment. The designed active thermal control method effectively regulates mean junction temperature and temperature fluctuation of power semiconductor devices within a safe operating limit. The practical feasibility and adoptability of proposed active thermal control is examined through a 2.2-kW DFIM laboratory prototype. [ABSTRACT FROM AUTHOR]

With the growing popularity of electrified transportation across the world, there have been extensive reports of research involving plug-in electric vehicles (PEVs), electric vehicle charging facilities (EVCFs) and their integration to the main electric grid, besides sustainable energy resources for powering these vehicles. This study proffers a power factor corrected level-1 DC public green-charging infrastructure accompanied by an integrated control, for electric light motor vehicles, compliant with recently formulated Indian charging standards. Power factor correction of plug-in electric vehicle charging current, solar photo-voltaic grid integration and charging of energy storage system is achieved using control of bidirectional AC/DC converters. A firmware and user interface for multimode off-board DC charging, with green, fast and semi-fast charging modes are investigated. Intelligent control for fast charging is also presented to reduce its pernicious impact on the grid. The simulation and hardware results verify the prime performance objectives of improving the local power quality and renewable energy utilisation with multimode charging, in the Indian context. The effectiveness of the proposed infrastructure is further demonstrated by a simulated use case, where 30 PEVs are randomly charged, in various modes, at this EVCF during busy commute hours. [ABSTRACT FROM AUTHOR]

In order to meet the growing load demand, the power utilities are transferred to restructuring process. The real power can be transmitted from the power producer to the customer for long distances. The reactive power is the background power which is necessary to transfer the real power in the power system. But the reactive power is absorbed by the transmission lines, transformers and high inductive loads. Hence the reactive power demand can be met by local regulating devices. It is mandatory to know the contribution of reactive power delivered by the regulating devices for the particular load condition. This paper presents the intuition of power flow tracing techniques to determine the amount of reactive power delivered by the regulating devices. The simulation results are compared using three different reactive power evaluation methods, namely, equivalent reactive compensation method, modified Ybus method and virtual power flow approach method. The contribution of individual power sources towards the reactive power is demonstrated on WSCC9 bus system and Indian utility 62 bus system. [ABSTRACT FROM AUTHOR]

The present research article is devoted to discussing the dynamic performance of a two-area interconnected power system consisting of hydropower plants. It tries to establish that using an HVDC transmission system in parallel with an EHVDC transmission line as an interconnection between two areas has a favorable effect on system dynamic performance in the wake of a small load disturbance in the system. At the outset of the article, the current status of the Indian Power System is summarized, and the challenges ahead for power engineers are discussed in length. The future prospects of hydropower due to environmental considerations, merits of using HVDC transmission systems, and the upcoming interconnected structure of power systems with parallel EHVDC/HVDC transmission systems is presented. The system dynamic performance has been studied with the implementation of optimal AGC regulators in the wake of load disturbance in one of the areas. The investigations carried out justify the application of an HVDC transmission link in parallel with an EHVDC transmission line as a system interconnection. The HVDC transmission link is considered to be operating in constant current control mode. The power flow deviation through the HVDC link is modeled based on frequency deviation at the rectifier end. Two modes of an HVDC link dynamic model--as an additional control variable with turbine controllers and as an additional state variable--have been investigated. Both modes of the HVDC link dynamic model offer the better system dynamic performance as compared to that obtained without considering an HVDC link in system dynamic modeling. [ABSTRACT FROM AUTHOR]