Rubin M1M3 support system dynamic performance

This paper introduces the direct-drive volumetric control (DDVC), focusing on the direct-drive pump-controlled hydraulic motor electro-hydraulic system as the primary subject of research. Aiming to address the problem of parameter uncertainties and unknown nonlinear disturbances in the system, a robust backstepping controller based on the extended state observer (ESO) is designed to improve the system's dynamic performance and robustness. In the controller, the ESO is used to estimate the total uncertainties in the system. Then, the robust backstepping controller is designed to enhance both the dynamic and robust performance. Moreover, Lyapunov theory is utilised to rigorously demonstrate the stability of both the ESO and the closed-loop control system. Finally, the results indicate the designed controller has excellent robustness and dynamic performance.

In this paper, the dynamic performance of an interconnected two-area non-reheated thermal power system with inherent nonlinearity due to generation rate constraint (GRC) present in the turbine has been investigated using a robust fractional order controller. The controller parameters have been optimized with the help of a recently proposed Salp Swarm Algorithm (SSA) based on the social behavior of Salpidae found in the deep ocean. Extensive simulation studies carried out in this paper establish that SSA optimized controllers provide significant improvement in the dynamic performance of the system even under parametric variations in comparison to genetic algorithm and bacterial foraging optimization algorithm optimized controller.

The variable stator vane (VSV) system is a key component of gas turbine supercharged rotor components for anti‐surge, and its performance directly affects the working stability and economy of the gas turbine. The effect of the VSV system on the dynamic characteristics and control performance of the gas turbine cannot be known. Then a refined model of the VSV system refined to design parameters established and studied to explore the effect of gas turbine dynamic performance based on co‐simulation. The effects of key parameters on the performance of the gas turbine system are analyzed by embedding the refined VSV model into the engine model. The simulation results prove that servo amplifier gain, viscous friction coefficient and dead band are sensitive structural parameters that affect the dynamic performance of the gas turbines. In the proposed appropriate interval, the optimal sensitive parameters can reduce the overshoot and adjustment time by about 51% and 7%. The gain of the servo amplifier is positively correlated with the maximum opening of the VSV. When the dynamic performance of the control system has been exerted to its extreme, some nonlinear parameters of the actuator can greatly improve the overall performance of the complex system.

H∞ control can guarantee the performance of a nominal ICPT system. However, the dynamic performance may suffer degradation when the parameter deviates from its nominal value. Thus, to enhance the overall dynamic performance of the ICPT system under parameter perturbations, an H∞ control method with a selected weighting function considering parameter perturbations is proposed in this article. First, a generalized state-space model is established to analyze the influence of parameter perturbations on the open-loop system in detail. After that, an uncertain model is established via frequency-domain analysis, generating a numerical solution of a weighting function used to describe the parameter perturbations. Then, the generalized plant with uncertainty is obtained and transferred into a standard H∞ optimal problem via small gain theory. Based on the proposed controller, the dynamic performance and robustness of the closed-loop system are analyzed and verified theoretically. Finally, simulation and experimental results further verify that the proposed H∞ control method can make the closed-loop system obtain good dynamic performance and strong robustness against parameter perturbations. The settling time is less than 6.8 ms without any overshoot when the system suffers parameter perturbations. Besides, the controller can maintain good dynamic performance in the startup and reference tracking experiments.

This article presents the design of optimal output feedback controllers to enhance the dynamic performance of wind turbine generator supplying an infinite bus through transmission line. Efforts have been made to propose optimal regulators based on feedback of output state variables, which are easily accessible and available for the measurement. The designed optimal output feedback controllers are implemented in the wake of step disturbance in the system. The system dynamic responses and pattern of closed loop system eigenvalues for various system states are obtained with the designed optimal regulators to investigate the system dynamic performance. The investigations of the results obtained reveal that the reduction in system states used for feedback has resulted in degradation of system dynamic performance. However, for a particular set of output variables used as feedback; five states are used for feedback for an eighth order original system. The system dynamic performance is the same as offered by optimal controllers based on full state vector feedback control strategy.

<div class="htmlview paragraph">In this investigation a robotic system's dynamic performance is optimized for high reliability under uncertainty. The dynamic capability equations allow designers to predict the dynamic performance of a robotic system for a particular configuration (i.e.,point design). While the dynamic capability equations are a powerful tool, they can not account for performance variations due to aleatory uncertainties inherent in the system. To account for the inherent aleatory uncertainties, a reliability-based design optimization (RBDO) strategy is employed to design robotic systems with robust dynamic performance. RBDO has traditionally been implemented as a nested multilevel optimization process in which reliability constraints require solution to an optimization problem (i.e., reliability analysis). In this work a robust unilevel performance measure approach(PMA) is developed for performing reliability-based design optimization which eliminates the lower level problem in RBDO. A robotic test problem is used to illustrate the efficacy of the approach.</div>

In this investigation a robotic system's dynamic performance is optimized for high reliability under uncertainty. The dynamic capability equations (DCE) allow designers to predict the dynamic performance of a robotic system for a particular configuration and reference point on the end-effector (i.e.,point design). Here the DCE are used in conjunction with a reliability-based design optimization (RBDO) strategy in order to obtain designs with robust dynamic performance with respect to the end-effector reference point. In this work a unilevel performance measure approach (PMA) is used to perform RBDO. This is important for the reliable design of robotic systems in which a solution to the DCE is required for each constraint call. The method is illustrated on a robot design problem

A novel method, aiming at solving the problem that the ultra-high-speed electric spindle tends to vibrate as its stiffness is small, using the repulsion of permanent magnets based on the theory that repulsion increased while the two magnets come close, is provided in this paper to design a electric spindle within additional support bearing system consist of two radial permanent magnet rings against each other. This paper also analyses the dynamic performance of radial permanent magnet bearings additional supporting system for ultra-high speed electric rotor system, result shows that the radial permanent magnetic bearings additional supporting system designed for improving the critical speed of the rotor system, reducing the rotor radial dynamic response, can effectively improve the dynamic performance and operational stability of ultra-high speed electric spindle rotor system.

Dynamic Model-based Saddle-point Approximation for Reliability and Reliability-based Sensitivity Analysis

Based on the servo drive hydraulic of system, using MATLAB/Simulink software in this paper, the impacts on system dynamic performances are analyzed and simulated of all the parameters (structure parameters J, Dp, and mechanism parameters A1, λ, k, V1, CP). According to the relation curve of the main systematic characteristics and dynamic performances obtained from the simulations, it provides advantages for system dynamic performance improvements. The simulation results indicate that dynamic performances can be improved through the reasonable selection of the system structural parameters. Also it laid the theoretical foundation for further study on energy saving of hydraulic injection machine.

To improve the dynamic response performance of a high-flow electro-hydraulic servo system, scholars have conducted considerable research on the synchronous and time-sharing controls of multiple valves. However, most scholars have used offline optimization to improve control performance. Thus, control performance cannot be dynamically adjusted or optimized. To repeatedly optimize the performance of multiple valves online, this study proposes a method for connecting a high-flow proportional valve in parallel with a low-flow servo valve. Moreover, this study proposes an algorithm in which a proportional–integral–derivative system and multivariable predictive control system are used as an inner loop and outer loop, respectively. The simulation and experimental results revealed that dual-valve parallel control could effectively improve the control accuracy and dynamic response performance of an electro-hydraulic servo system and that the proportional-integral-derivative–multivariable predictive control controller could further dynamically improve the control accuracy.

The dynamic characteristic of the timing system has a significant impact on the performance of the engine's NVH. With low contact stress and strong anti-interference ability, the arc tooth synchronous belt was adopted by engine timing transmission system. The multi-body dynamics model of the in-line four cylinder engine timing system was established. We explored the influence of crankshaft speed and initial tension on the dynamic performance of the engine timing system. The result shows when the crankshaft speed V= 2000 r/min and the initial tension of the synchronous belt F= 300 N, the load distribution of the RU type synchronous belt teeth root is more uniform. The stress is 0.2474 N/mm2 lower than the average value, and the transverse vibration amplitude decreases by 0.3067 mm. Under this circumstance, the fluctuation amplitude of camshaft angular velocity is 6.5312 rad/s lower than the maximum average amplitude, so the transmission error is reduced by 37.95 %. The fluctuation amplitude of interference value decreases by 0.3413 mm, and the fluctuation amplitude of interference velocity decreases by 263.8908 mm/s. The synchronous belt based engine timing transmission is more stable and the dynamic performance is better. It laid a solid foundation for the optimization of the tooth profile and load conditions of the engine timing system.

Reasonable ratio between the load inertia and servo motor inertia plays a decisive role for the dynamic performance and stability of the servo system, as well as the machining accuracy of the whole CNC machine. In order to improve the control performance and contour machining accuracy of the servo system of the CNC cycloidal gear form grinding machine, an optimization design method of the inertia matching for the CNC cycloidal gear form grinding machine servo system is proposed. The two-mass servo driving closed-loop PID control system is constructed, the influence of the different inertia ratios on the dynamic performance and contour errors of the servo system are deeply analyzed, and the inertia ratio is optimized to satisfied with the servo system performance requirements. Finally, the feasibility and practicability of the optimization design method of inertia matching are verified through the inertia ratio optimization grinding experiments of the cycloid gear in the CNC gear form grinding machine. This inertia matching optimization design method provides a valuable reference for the further design of CNC machine servo system.

This chapter presents a method for evaluating dynamic performance of multi-state systems with a general series parallel structure. The system components can be either repairable binary elements with given time-to-failure and repair time distributions, or 1-out-of-N warm standby configurations of heterogeneous binary elements characterized by different performances and time-to-failure distributions. The entire system needs to satisfy a random demand defined by a time-dependent distribution. Iterative algorithms are presented for determining performance stochastic processes of individual components. A universal generating function technique is implemented for evaluating the dynamic system performance indices. Examples are provided to demonstrate applications of the proposed methodology.

As smart-grid technology develops, the energy storage system (ESS) is widely used. By controlling exchange of either active or reactive power between ESS and power system, power system's damping and dynamic performance can be improved. Aiming at meeting the requirements of online applications of Wide-Area damping control, this paper adopts Electric torque analysis (ETA) to realize the analysis of small signal stability of power system. Based on the two-machine equivalent system, this paper explores the definition of the ETA method, as well as its mathematic relationship with the MA method, and the condition of stability. An online optimization scheme of ESS is presented, which is based on damping control, to maximize the damping torque coefficient with the synchronizing torque restraint. Finally, the paper uses a 4-machine-2-area benchmark to verify the effectiveness and superiority of the proposed optimization method.