Development and Control Strategy of Subsea All-Electric Actuators

The development of subsea all-electric Christmas trees is an area of focus in the offshore oil industry worldwide.The main difficulties are associated with the development and control strategies for subsea all-electric actuators,which are the most criti-cal components of subsea Christmas trees.A single-motor-level fuzzy PID control with an integrated working condition detection mod-ule and a three-motor redundant-level deviation strategy with coupled joint synchronous control were proposed in this paper to real-ize the real time determination of algorithm parameters according to the working conditions,solve the rapid redistribution problems,and maintain the fast speed of the servo motor of the subsea all-electric tree valve actuator.A synchronous control electrical system was built,tested,and verified through simulation analysis.Test results show that the two redundant servo motors can still control the all-electric valve actuator and provide good synchronization control capabilities despite the failure of one servo motor,and the verti-cal and horizontal vibration values of the system are within reasonable ranges.The synchronous control strategy can be applied to the synchronous control problem of subsea all-electric production systems,which is of considerable importance for the development of subsea all-electric production systems.

Modeling and Simulation of Cooperative Exploration Strategies in Unknown Environments

Cooperative spatial exploration in initially unknown surroundings is a common embodied task in various applications and requires satisfactory coordination among the agents.Unlike many other research questions,there is a lack of simulation platforms for the cooperative exploration problem to perform and statistically evaluate different methods before they are deployed in practical scenarios.To this end,this paper designs a simulation framework to run different models,which features efficient event scheduling and data sharing.On top of such a framework,we propose and implement two different cooperative exploration strategies,i.e.,the synchronous and asynchronous ones.While the coordination in the former approach is conducted after gathering the perceptive information from all agents in each round,the latter enables an ad-hoc coordination.Accordingly,they exploit different principles for assigning target points for the agents.Extensive experiments on different types of environments and settings not only validate the scheduling efficiency of our simulation engine,but also demonstrate the respective advantages of the two strategies on different metrics.