Driven by sustainable development targets, the energy transition is taking place in the electrical distribution networks with increasing integration of renewable energy sources (RES), especially solar photovoltaic (PV). However, the intermittency and randomness of RES introduce operational difficulties to the distribution system operators (DSOs) in terms of voltage limit violations and transformer overloading. The PV inverters can curtail the power generation, leading to the loss of energy yield of the PV owners. These adverse impacts become significant barriers to further deployments of RES in the distribution networks, especially at the low-voltage (LV) level. Furthermore, the distribution network reinforcements will require a substantial investment given the large scale of the networks. The investment might not be cost-effective when the problems caused by RES occur not very often. The recent adoption of advanced sensors, smart meters, and information and communication technology at the grid edges, i.e., interface points between the LV networks and the end-user installations, principally paves the way to deploy the emerging monitoring and control functionalities. Therefore, this thesis investigates the observability and controllability of these grid-edge technologies to assist the LV distribution networks in accommodating a higher share of RES. This PhD thesis presents the importance of grid-edge monitoring and control strategies that will help stimulate the integration of RES, such as PV systems in LV distribution networks and support the networks in its operation. The developed grid-edge monitoring and control strategy focuses on solving the transformer overloading and voltage rise problems by exploiting the RES controllability and digital transformation. The energy transition in the distribution networks, hence, can be facilitated.