Large-scale demand response (DR) is a useful regulatory method used in high proportion renewable energy sources (RES) integration power systems. Current incentive-based DR schemes are unsuitable for large-scale DR due to their centralized formulation. This paper proposes a distributed scheme to support large-scale implementation of DR. To measure DR performance, this paper proposes the customer directrix load (CDL), which is a desired load profile, to replace the customer baseline load (CBL). The uniqueness of CDL makes it more suitable for distributed schemes, while numerous CBLs have to be calculated in a centralized manner to ensure fairness. To allocate DR tasks and rebates, this paper proposes a distributed approach, where the load serving entity (LSE) only needs to publish a total rebate and corresponding CDL. As for each customer, s/he needs to claim an ideal rebate ratio that ranges from 0 to 1, which indicates the proportion of rebate s/he wants to get from LSE. The rebate value for each customer also determines his or her DR task. Then, the process of customer claims for the ideal rebate ratio is modeled as a non-cooperative game, and the Nash equilibrium is proved to exist. The Gossip algorithm is improved in this paper to be suitable for socially connected networks, and the entire game process is distributed. Finally, a large-scale DR system is formulated. The simulation results show that the proposed DR can promote the consumption of RES. Additionally, this scheme is suitable for large-scale customer systems, and the distributed game process is effective.

As a typical cyber physical system (CPS), a smart grid should facilitate more robust integration and interoperability of information models and subsystems so that the performance of the physical system can be optimized. However, the intrinsic complexity and heterogeneity of CPS are two of the biggest obstacles to interoperation and interconnection among various information models and subsystems. In order to address the dilemma, this paper proposed a systematic, data-centric system design approach comprehensively including data-oriented system architecture, data resources abstraction and data-driven mechanisms. To be specific, the autonomous decentralized system (ADS) theory is introduced to establish the data-centric system architecture. A MQTT/MQTT-SN-based communication protocol, which supports not only IP-based devices but also non-IP devices, is proposed to meet the requirement of publish-subscribe mechanism of the ADS-based system architecture. A data-centric meta-interface is proposed to formalize the data resources abstraction. A Lebesgue sampling-based data exchange mechanism, which is proven tractable but effective, is proposed to realize the data-driven mechanism. As user energy management system (UEMS) is an integral part of smart grid, a realistic UEMS for heating project is considered a typical case to study the performance of the proposed data-centric system. This paper is one of the first few papers that systematically propose a systematic data-centric system design approach for a smart grid, which is supported by aspects of system architecture, communication protocol and data exchange mechanism.

As one of the typical cyber physical systems (CPS), the user energy management system (UEMS) plays an increasingly significant role in the smart grid, such as participating in automated demand response (ADR). Traditional analyses related to the UEMS in ADR programming mainly focus on energy management strategies or algorithms, where the interdependence and interplay between the cyber system and the physical system is neglected. This paper firstly presents an ADR control strategy of the UEMS with the objective of minimizing electricity bills and meeting users' comfort constraints. Then, a hybrid scheme including Message Queuing Telemetry Transport (MQTT) and Message Queuing Telemetry Transport for Sensor Network (MQTT-SN), which are publish-subscribe communication protocols, is developed to establish the cyber system of the UEMS. To evaluate the cyber-physical performance of the UEMS in ADR programs, the hybrid dynamic models of major behaviors of the UEMS are proposed and a UPPAAL (http://www.uppaal. org/)-based methodology of the formal specification and verification is also proposed. In case studies, the impact of communication reliability on the proposed ADR control strategy is studied and the quality of service (QoS) mechanism provided by MQTT/MQTT-SN is demonstrated as a cost-effective solution for the ADR control strategy under unreliable communication.observable Markov decision process approaches in home energy management system (HEMS) for minimizing the household electricity bills in the real-time pricing market [6]. Erol-Kantarci et al. compares an in-home energy management application with an optimization-based residential energy management scheme in the aspect of energy saving and peak load shift under the presence of local energy generation capability, prioritized appliances, and for real-time pricing [7].Cyber systems such as communication networks and computing modules are indispensable for those strategies or algorithms. However, the cyber systems are always assumed to be ideal in these literatures. In other words, these algorithms may lose efficacy in real projects due to the interdependence and interplay between the cyber system and physical system [8]. For instance, unreliable communication cannot conduct commands exactly, so it may deteriorate the performance of algorithm. To reduce the risks and to develop methods for improving system efficiency, the cyber-physical characteristics of the UEMS should be studied.Besides the communication reliability, as a networked control system composed by intelligent electronic devices, a UEMS must accomplish some logical verification to achieve reliable control. Although the formal methodology is one of the critical methods in CPS analyses and can ensure the system robustness from the aspect of logic, there are rare researches related to the formal methodology analyzing the reliability of the UEMS in ADR. The formal-methodology-based cyber-physical analyses mainly focus on distribution networks, such as intelligent substations based on IEC61850 [9][10][11] o...

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