The paper presents a conceptual framework for integrating electric vehicles (EVs) into electric power systems, covering both grid technical operation and electricity markets. It discusses the impacts and benefits of EV integration, including their ability to provide ancillary services like peak power and spinning reserves through the V2G concept. The framework includes a hierarchical control structure and market mechanisms to manage EV charging effectively. Two case studies are presented, showing the benefits of smart charging strategies over uncontrolled approaches. The first case study examines the impact of EVs on a medium voltage (MV) network and the benefits for the distribution system operator (DSO). The second case study analyzes the dynamic behavior of a small low voltage (LV) grid and a larger MV grid operated in islanded mode. The paper also discusses the technical impacts of EV integration on MV networks, including potential branch congestion and voltage drops. It presents a detailed analysis of EV characteristics, charging strategies, and the effects of different charging approaches on grid performance. The results show that with smart charging strategies, a higher percentage of EVs can be integrated without requiring grid reinforcements. The dual tariff policy and smart charging methods are evaluated, with smart charging allowing for a significantly higher EV penetration level without violating voltage limits. The paper also explores the dynamic operation of EVs in isolated systems, showing how they can contribute to primary frequency control and improve system stability. The integration of EVs with microgrids and multimicrogrids is discussed, highlighting their potential to enhance system performance and reduce the need for dedicated storage. The study concludes that the proposed framework and strategies can effectively manage EV integration, reducing negative impacts and enhancing the benefits of EVs in the power system.The paper presents a conceptual framework for integrating electric vehicles (EVs) into electric power systems, covering both grid technical operation and electricity markets. It discusses the impacts and benefits of EV integration, including their ability to provide ancillary services like peak power and spinning reserves through the V2G concept. The framework includes a hierarchical control structure and market mechanisms to manage EV charging effectively. Two case studies are presented, showing the benefits of smart charging strategies over uncontrolled approaches. The first case study examines the impact of EVs on a medium voltage (MV) network and the benefits for the distribution system operator (DSO). The second case study analyzes the dynamic behavior of a small low voltage (LV) grid and a larger MV grid operated in islanded mode. The paper also discusses the technical impacts of EV integration on MV networks, including potential branch congestion and voltage drops. It presents a detailed analysis of EV characteristics, charging strategies, and the effects of different charging approaches on grid performance. The results show that with smart charging strategies, a higher percentage of EVs can be integrated without requiring grid reinforcements. The dual tariff policy and smart charging methods are evaluated, with smart charging allowing for a significantly higher EV penetration level without violating voltage limits. The paper also explores the dynamic operation of EVs in isolated systems, showing how they can contribute to primary frequency control and improve system stability. The integration of EVs with microgrids and multimicrogrids is discussed, highlighting their potential to enhance system performance and reduce the need for dedicated storage. The study concludes that the proposed framework and strategies can effectively manage EV integration, reducing negative impacts and enhancing the benefits of EVs in the power system.