Aiming at the problem that traditional household power routers are susceptible to grid voltage changes and caused by DC bus voltage imbalance, this paper proposes a single-phase full-bridge three-level household energy router with intelligent control at the edge of distribution network. The proposed energy router structure consists of a rectifier-DC link-inverter, and the solar photovoltaic and battery energy storage systems are connected to the DC link. At the same time, an intelligent control method at the edge of the power grid is adopted, which uses the bidirectional characteristics of the power router to adjust the feedback through the load voltage, so that the input voltage can be changed within a certain range. This energy router can be controlled by power factors to regulate active and reactive power output, while reactive power can be injected on the grid side to regulate the voltage. The hardware-in-loop results verify that the proposed energy router can realize the bidirectional flow of energy, so as to adjust the output voltage of the load end or provide reactive power support to the grid side.

With the continuous increase of high-power loads such as residential air conditioning and floor heating, the resulting load fluctuations and serious problems of voltage reduction at the end of the distribution lines have become increasingly prominent, which brings great challenges to the operation control and power quality management of power supply utilities. There need to be more intelligent, convenient, and effective solutions. This paper proposes an intelligent control scheme for power supply quality control of electricity distribution networks to solve this problem. A complete set of control devices are also designed in this paper. Multiple monitoring devices are installed on low-voltage distribution networks. This realizes effective monitoring of abnormal voltage data in the distribution network and compensates for the shortage of monitoring equipment in the low-voltage distribution network. Through the design of an intelligent two-way AC contactor, the alternative power supply can be automatically switched after equipment failure to achieve automatic voltage regulation. The intelligent and reliable system voltage regulation is realized by combining voltage regulation of transformer on-load tap changer, line reactive capacitors, and standby power supply. This scheme can save labor costs, ensures power supply quality and reliability of the distribution network, and has potential significance for improving power supply quality at the end of distribution lines.

Investment in distributed generation (DG) is an attractive planning option for enhancing the reliability and security of power distribution systems. However, uncertainties due to intermittent generation of renewable energy based DGs i.e. wind turbines (WTs) and solar photovoltaics (PVs) are a challenge for DG integration. This work proposes a robust distributed generation investment planning (DGIP) which considers the uncertainties associated with the intermittent renewable generation and variable electricity demand. The proposed DGIP minimizes the net present value (NPV) of total costs of investment, operation, maintenance and emissions of WTs and PVs. The proposed planning solution is assessed using the 53-bus test feeder and the numerical result demonstrates its benefit against the conventional solution.