ABB Ltd

About: ABB Ltd is a company organization based out in Zurich, Switzerland. It is known for research contribution in the topics: Voltage & Signal. The organization has 6222 authors who have published 6852 publications receiving 83994 citations.

Thermoelectric energy storage system with an intermediate storage tank and method for storing thermoelectric energy

Abstract: A system and method are provided for storing electric energy in the form of thermal energy A thermoelectric energy storage system includes a working fluid circuit for circulating a working fluid through a heat exchanger, and a thermal storage medium circuit for circulating a thermal storage medium The thermal storage medium circuit includes at least one hot storage tank, an intermediate temperature storage tank, and a cold storage tank connected together via the heat exchanger A proportion of the storage medium is redirected to or from the intermediate storage tank from or to the hot or cold storage tank, joining another proportion which flows directly between the cold and hot storage tank

A robot safety system and a method

Abstract: A robot safety system configured to protect humans in the vicinity of a working robot (1, 11, 21, 31) against harmful impacts by said robot (1, 11, 21, 31), said safety system comprising a sensor system (3, 13, 23) and a safety controller (4, 14, 24) configured to establish an impact risk profile of the robot (1, 11, 21, 31) and deliver an operating signal to a robot controller (2, 12, 22) based on said impact risk profile, wherein the safety controller (4, 14, 24) is configured to establish the impact risk profile based on stored data and input signals, and that the stored data and input signals comprise stored impact data, stored data related to the path of the robot (1, 11, 21, 31), and signals from the sensor system of events in the vicinity of the robot (1, 11, 21, 31), such as a detected human (P1, P11, P21, P22, P31, P32) in the vicinity of the robot (1, 11, 21, 31).

Kinematic analysis and error modeling of TAU parallel robot

Abstract: The TAU robot presents a new configuration of parallel robots with three degrees of freedom. This robotic configuration is well adapted to perform with a high precision and high stiffness within a large working range compared with a serial robot. It has the advantages of both parallel robots and serial robots. In this paper, the kinematic modeling and error modeling are established with all errors considered using Jacobian matrix method for the robot. Meanwhile, a very effective Jacobian approximation method is introduced to calculate the forward kinematic problem instead of Newton–Raphson method. It denotes that a closed form solution can be obtained instead of a numerical solution. A full size Jacobian matrix is used in carrying out error analysis, error budget, and model parameter estimation and identification. Simulation results indicate that both Jacobian matrix and Jacobian approximation method are correct and with a level of accuracy of micron meters. ADAMS's simulation results are used in verifying the established models.

Frequency Sensitivity and Electromechanical Propagation Simulation Study in Large Power Systems

Abstract: A global view of power system's frequency behavior opens up a new window for analyzing system's dynamics. With the aid of global positioning system, measurements from different locations would have synchronous time; therefore a system-wide observation and analysis would be possible. As part of the US-wide power frequency monitoring network project this paper focus on simulation study results of power frequency dynamics of the Eastern U.S. system. The study assesses the frequency measurement accuracy needed to observe frequency dynamics from events such as remote generation drops. Electromechanical-wave propagation phenomena during system disturbances have been observed. The speeds of electromechanical-wave propagation in different areas of the U.S. systems were estimated and their characteristics were discussed.

Multi-Agent System-Based Real-Time Load Management for All-Electric Ship Power Systems in DC Zone Level

Abstract: All-electric ship power systems have finite generation and include a large portion of dynamic loads and nonlinear loads relative to the total power capacity. Therefore, the load demand and power generation of the system should be matched in real-time. In this paper, a novel multi-agent system-based real-time load management technique is proposed to optimally determine the switch status of loads in DC zones while satisfying the operating constraints of the system in real-time. The multi-agent system cooperative control protocol is developed based on a proposed reduced-order agent model and artificial potential function of the multi-agent system, which aims to maximize the energized loads in the all-electric ship power system. The cooperative controller aims to cooperatively achieve the group objectives that are difficult to reach by centralized controller. Further, simulation results verify the viability and performance of the proposed technique in PSCAD/EMTDC software.