Multi-agent based hierarchical hybrid control for smart microgrid

This paper studies the smart control issue for an autonomous microgrid in order to maintain the secure voltages as well as maximize economic and environmental benefits. A control scheme called as multi-agent based hierarchical hybrid control is proposed

Procjena prijelazne stabilnosti dvopodručnog energetskog sustava s CSC-STATCOM-om zasnovanom na LQR-u

A current source converter (CSC) based static synchronous compensator (STATCOM) is a shunt flexible AC transmission system (FACTS) device, which has a vital role as a stability support for small and large transient instability in an interconnected power network. A robust linear quadratic regulator (LQR) based controller for CSC-STATCOM is proposed. In this paper, LQR based CSC-STATCOM is designed to enhance the transient stability of two-area two-machine power system. First of all, modeling & LQR based controller design for CSC-STATCOM are described. After that, the impact of the proposed scheme on the test system with different disturbances is demonstrated. The feasibility of the proposed scheme is demonstrated through simulation in MATLAB and the simulation results show an improvement in the transient stability of power system with CSC-STATCOM. Also, the robustness and effectiveness of CSC-STATCOM are better rather than other shunt FACTS devices (SVC & VSC-STATCOM) in this paper.Statički sinkroni kompenzator (STATCOM) zasnovan na pretvaraču strujnog izvora (CSC) je uređaj za izmjenični prijenos s fleksibilnim "shuntom" (FACTS), koji značajno doprinosi stabilnosti malih i srednjih prijelaznih nestabilnosti u međusobno povezanoj energetskoj mreži. Ovdje je predložen robusni sustav upravljanja zasnovan na linearnom kvadratičnom regulatoru (LQR) za CSC-STATCOM. U ovom radu, CSC-STATCOM zasnovan na LQR-u dizajniran je za povećanje stabilnosti dvopodručnog energetskog sustava s dva motora. Prvo su opisani postupak modeliranja te upravljački sustav zasnovan na LQR-u za CSC-STATCOM. Nakon toga, prikazan je utjecaj predstavljene sheme na ispitni sustav uz prisutnost različitih poremećaja. Provedivost predstavljenog pristupa je prikazana kroz MATLAB simulacije čiji rezultati prikazuju poboljšanje u prijelaznoj stabilnosti energetskog sustava s CSC-STATCOM-om. Također, u ovom radu je prikazana veća robusnost i efikasnost CSC-STATCOM "shunt" FACTS uređaja u odnosu na SVC i VSC-STATCOM

Hierarchical hybrid control for improving comprehensive performance in smart power system

For the purpose of improving comprehensive performance including stability, security and economic benefit of power system, in this study a two-level hierarchical hybrid control is proposed in a real-time manner. First, a novel hybrid model is founded to clearly explain the hybrid dynamical behaviors of the power systems. On the basis of the model, a hybrid control scheme is designed in an interaction manner between the discrete control strategies at the upper level and the continuous dynamical controls at the lower level. The upper level discrete control strategies are responsible for converting operating modes to guarantee the security during significant disturbances and the economic benefit of overall system. After locating operating modes, the lower level local continuous controllers are responsible for regulating dynamic behavior of each controlled unit to obtain the satisfactory stability performance. The effectiveness of the proposed hybrid control is demonstrated through simulation examples

Transient control for micro-grid with multiple distributed generations based on hybrid system theory

With the rapid increase in the rate of distributed generation (DG) penetration depth, the issues of improving micro-grid transient become more significant. This paper investigates a two-level hierarchical hybrid control consists of continuous local controller for each DG unit at the first level coordinated by discrete supervisory control strategies at the secondary level for transients performance enhancement of micro-grid with various DG units following pre-planned or accidental events. The discrete supervisory control strategies are established based on information fusion technique by using wide-area measurements (WAMs) in order to switch each DG subsystem into apposite operational mode following large disturbances. The continuous local controller for each DG unit is designed based on multiple Lyapunov stability theory integrating linear matrix inequality (LMI) techniques in order to regulate the set point of each DG subsystem to reach the best performance and acceptable operation indexes. The effectiveness of the proposed hybrid control is demonstrated through simulation examples

Decentralized Coordinated Excitation Control for Large Power System Based on Novel Delay-dependent Non-linear Robust Control Algorithm

Technological advances of the wide-area measurement system have enabled the use of a combination of measured information from remote locations for stability enhancement of large power systems. However, the time delays introduced by remote transmission i

Optimal control for switched systems with impulsive effects

In this paper, we studies the optimal control problem for controlled switched systems with impulsive effects. By establishing the dynamic programming principle for this kind of system, we derive the necessary conditions for optimality of an associated hybrid performance functional. Next, we provide the sufficient conditions for optimality. Specializing the obtained results to the case of linear controlled switched systems with impulsive effects, we derive the corresponding sufficient conditions. Finally, one example is given to illustrate the results

Optimal control with stabilization for a class of hybrid dynamical systems

This paper studies the optimal control with stabilization issue for a class of hybrid dynamical systems (HDS) with hybrid performance functional (HPF). By employing Lyapunov function method and the recent results of stability of HDS, the optimal control conditions for the HDS has been derived with respect to the HPF. Under the state feedback control, the closed-loop HDS is globally asymptotically stable (GAS) and at the same time the HPF can achieve the desirable maximal (minimal) value. The results are then used to study the case of linear HDS with hybrid quadratic performance functional (HQPF). The matrix inequality conditions are derived to design the linear feedback controller under which the closed-loop linear HDS is GAS and the HQPF is optimized. Finally, one example is given for illustration

Two-level hierarchical hybrid control for smart power system

This paper studies the smart control issue for large power systems to effectively solve the problems of security, stability, and economical efficiency. A control scheme called as hierarchical hybrid control is proposed versus the hierarchical structure a