The Internet of Things Based Fault Tolerant Redundancy for Energy Router in the Interacted and Interconnected Micro Grid

The distribution energy router (DER) is the core of the interacted and interconnected micro grid in future distribution network, which fully meets the needs of the ubiquitous power internet of things (IOT) based future distribution network. The reliability of micro grid which applies the DER is highly related to its cascaded full-bridge converters. With the redundant full-bridge converters and IOT technology, the DER can stand the component failures, hence improve the robustness of the DER as well as the future interacted and interconnected micro grid. For a ubiquitous power IOT technology based DER, this paper proposes a redundancy design for fault tolerant strategy. Several redundancy designs are discussed in detail with operational principles and control strategies. The proposed redundancy design is implemented on the power circuit of one phase for DER consists of a nine-level cascaded full-bridge converter in Saber simulation platform, and the simulation results prove that the redundancy design can minimize the customer’s power interrupt time and the consequent damages to the system.

Reliability optimization of wind farm power systems using bat algorithm with generalized flight

In this paper, two metaheuristics, namely the Bat algorithm (BAT) and a recent hybridization of bat algorithm with generalized walk evolutionary algorithm are presented. The bat algorithm and the Bat algorithm with generalized flight (BAG) are used to solve the problem of optimal redundancy design of series-parallel electrical systems. In order to assess the reliability of the heterogeneous system of multi-state series-parallel, the Ushakov method a universal moment generating function (UMGF) is used to allow fast estimation. The design objective is to maximize the reliability of the bulk power generation system from wind farm. The components of each electrical subsystem are characterized by their performance (capacity), cost and reliability. Reliability is defined as the ability to satisfy consumer demand that is given by a cumulative load curve. By comparing three algorithms cited in this study, the results show that the hybridization of Bat and Generalized Evolutionary Walk Algorithm (BAG) are effective in solving the reliability redundancy optimization problem (RROP). Two illustrative examples are presented.

Review of Aerospace Actuator Technology

Actuator systems are widely used in rockets, missiles, airplanes, and other aerospace vehicles for the attitude control of aerospace. The application of high-performance actuators is crucial in improving the maneuverability and rapidity of aerospace. To promote the development of aerospace actuator technology, the main trend of actuator technology development is proposed, and a comprehensive summary of actuator systems is given. First, the application and function of an actuator system are introduced briefly. Second, the types and characteristics of the actuators are introduced in detail, and the technical development of the actuator is presented. Third, the main types and functional characteristics of the energy supply of aerospace are introduced, and comparative analysis is performed on the basis of the feature that ground energy cannot be used in aerospace. Fourth, the redundancy design technology of actuators is discussed, and the development and application of redundancy technology are examined. Fifth, several typical nonlinear actuator control models are introduced, and the nonlinear control strategies of actuators are summarized and analyzed. Finally, high power electrohydraulic, medium–high power electrohydrostatic, and medium–small power electromechanical actuators should be the key future development direction of aerospace ctuators.

IMPROVEMENT OF NETWORK SURVIVABILITY USING THE EFFECTIVE REDUNDANCY DESIGN

Network survivability is a very important issue due to the sustainability of the network services. Failure in a network system conduce to disturbance of the network services and causes trouble to millions of applications. Implement an effective redundancy design is one of method to cope nuisance in terms of sustainability in a network. In this paper, there are two design networks with and without redundancy respectively by Metro Ethernet-based technique to support transmission of data and voice. Furthermore, there is a validation performance of networks by measuring and comparing the throughput, latency and jitter between the two network designs. The value of bandwidth capacity is 100 Mbps as plan bandwidth link. Measurements results denote that network with redundancy design is able to enhance performance of the network, the parameters are: the throughput on single link tends to moderate (25%-50%), on the other hand, the throughput values on the main link and back uplink are in accordance with very good condition (75%-100%). The values of frame loss ratio 69.979% - 56.679% (single link), 6.77% -9.999% (main link) and 6.676 %-9.999% (back uplink). The values of jitter and latency in network with redundancy design are much better than in single link network. The recovery time for each frame length is ranging from 48.999ms to 49.887ms, where it is still meet with the standard that must below 50ms. Finally, when the main link in the network topology with redundancy design undergo link fails condition, the backup link is able to maintain the quality of network throughout that time, on the contrary, network topology without redundancy design is unable.

Virtualising redundancy of power equipment controllers using software-defined networking

Power system automation is heavily dependent on the reliable interconnection of power system field equipment and centralised control applications. Particularly important to achieve reliability in automated power systems is the redundant connection of field equipment controllers. Today, the fundamental redundancy management and switch-over processes are handled by the power system control applications itself. This, however, increases the complexity of the control systems and leads to an intersection of concerns. Consequently, the design and the implementation of field equipment controller redundancy is time-consuming and cost-intensive. In this paper, we propose the implementation of a redundancy virtualisation layer for power system controllers based on software-defined networking (SDN). The goal is to relieve the control applications from managing field level redundancy. Thus, our SDN approach allows to detect gateway failures and to perform transparent switch-overs. This significantly simplifies the configuration of the control application with redundant components and finally leads to more flexible and simplified redundancy design, deployment and operation. Arbitrary redundancy topologies, such as triple-controller-redundancy can be implemented without modifying the control applications.