The installed capacity of solar photovoltaic (PV) based generating power plants has increased significantly in the last couple of decades compared to the various renewable energy sources (VRES). As a result, the increased penetration of solar PV-based generating units leads to several issues related to power quality, system stability, and reliability. In view of these concerns, various international standards and grid codes have been amended t. The installed capacity of solar photovoltaic (PV) based generating power plants has increased significantly in the last couple of decades compared to the various renewable energy sources (VRES). As a result, the increased penetration of solar PV-based generating units leads to several issues related to power quality, system stability, and reliability. In view of these concerns, various international standards and grid codes have been amended to address such critical issues. Therefore, most solar PV-based generating units have undergone several changes in operational and control structure. Subsequently, varieties of solar PV configurations and control structures have been proposed by several researchers to augment the desired operational features. This paper presents a comprehensive review of various solar PV configurations, control strategies, and ancillary services with multifunctional features within this context. The utilization and benefits of various configurations and their practical aspects have been discussed thoroughly for all the configurations and architectures. Apart from this, the control aspects of grid-connected solar PV systems are categorized into two important segments, namely, a) DC-side control and b) AC-side control. This article covers the important features, utilization, and significant challenges of this controller and summarizes the advanced control techniques available in the literature. Further, the various control techniques have been compared concerning different operational para. ••An overview of solar photovoltaic (PV) power generation in respect of all the other renewable energy sources (RES) have been presented on cumulative basis.••The different solar PV configurations, international/ national standards and grid codes for grid connected solar PV systems have been highlighted.••The state-of-the-art features of multi-functional grid-connected solar PV inverters for increased penetration of solar PV power are examined.••The various control techniques of multi-functional grid-connected solar PV inverters are reviewed comprehensively.Ancillary servicesgrid-integrated photovoltaic (PV) systemmulti-functional solar inverterssolar PV system configurationsThe continuously escalating prices of energy generation from conventional energy sources and the rising environmental concerns have increased the scenario of electricity generation from low-carbon green energy resources. In several regions of the world, solar PV (SPV) based energy generation is becoming the most affordable choice for producing power, which is anticipated to be a heavy investment in the coming years,,,,,,,,,,,. Moreover, modern electric power networks are rapidly transitioning toward a distributed network having a larger dependency on renewable energy sources such as solar and wind. Apart from this, the energy storage technologies such as batteries, supercapacitors, and fuel cells are also increasing to support energy generation from solar PV systems. Besides the continuously declining prices of solar panels, favorable government policies and continuous enhancement of research in this area have led to the proliferation of SPV integration,,. In view of this, there will be an addition of roughly 2 TW solar PV power cumulatively to the existing global power network between the years 2022 to 2026. Additionally, solar photovoltaics has been the second-largest renewable energy source since 2020 in terms of increased energy production. On a broader aspect, the SPV system not only helping the conventional energy sources during peak hours but also curbing the contiguous growth of CO2 emissions. This way, to enhance the decarbonizing process. There are a number of challenges that arise with the insertion of large-scale PV generation into power grids, prominent among them being changes in PV active power output caused by intermittent solar irradiation and its effects on system reserve. In the early stages of PV development and power application, the majority of PVs were built to instantly unplug from the power grid in case of a system disturbance, mainly if the disturbance occurred close to the PV plant. Grid-integration technical requirements must be satisfied at commissioning since they govern grid-connected PV systems' design, administration, and operation. These are “grid standards” or technical requirements for the system. Initial needs focused on power quality in rated conditions with maximum power point tracking (MPPT). Interconnection guideline criteria include voltage flicker, harmonics, control, and protection coordination.IEEE Standard 1547, IEEE 929-2000, IEEE 1547.5, IEEE 519, IEC 555, and IEC 61000,,,,,,,,,,,,, are some examples of existing guidelines and standards of technical requirements for VRESs integration into the electricity grid. These technical specifications guarantee the controllers, protection, and power quality indices for PV systems. The current grid technical requirements or standards for PV systems are required to update as necessary, and the solar PV power convert.
