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In view of the current domestic agricultural tractor manual shift operation time is long, Shift impact large and the actual situation of the shift operation effort, combined with the tractor running complex working environment and the driver uneven operation level, this paper designed and developed a tractor transmission electronic control system. According to the bench test and vehicle test, the...
Real-time simulation of modular multilevel converter (MMC)-based HVDC is one of the most important and difficult technologies in the area of power electronics research. This paper presents a methodology for the hardware in loop (HIL) CPU/FPGA-based real-time simulation of a one-terminal MMC HVDC of up to 468 levels using a detailed equivalent model, and the simulation system is based on full-scale...
The need to improve the quality of management at minimum costs, the complexity of the structure of the management object, the functions performed by it, leads to an increase in uncertainties that need to be taken into account. The use of fuzzy logic to control pumping equipment will reduce the likelihood of erroneous decisions, which will increase the life of technological equipment.
Using automatic instead of automated tools is assumed to significantly reduce timing budgets needed for the actualization. However, it seems to be not always the case, especially if we consider the complete actualization cycle. The article presents an investigation of the time needed for the information base actualization when using separate automated or automatic tools, as well as the time needed...
State Grid of China has constructed multiple ultra high-voltage direct current (UHVDC) projects in recent years. UHVDC projects like Ximeng-Taizhou are hierarchically connected to different AC systems at the receiving end. The high voltage and low voltage valve groups on the hierarchical side are connected to different AC systems, and different tap changer steps of transformers, measurement error,...
This paper is devoted to the theoretical and experimental investigation of control system of triode high voltage glow discharge electron gun. Control system consists on two connected depended parts: system of gas-dynamic control of the gas pressure in the discharge gap and system of electric control of beam power. These two systems have been realized as one complex control system. Main theoretical...
Traditional HVDC systems employ line commutated converters (LCCs) which are prone to commutation failures and feature significant harmonic distortion. Voltage source converter (VSC)-based HVDC systems have been employed to overcome these disadvantages, but their high switching frequency makes it difficult to scale to high power levels. Recently, a VSC topology named modular multilevel converter (MMC)...
In order to verify the integrity of the insulation of a superconducting magnet, the Paschen test is needed to perform on the insulation after its manufacture. The vacuum vessel for the Paschen test is required to keep for an adequately long time under the pressure values of different degrees. To achieve the low pressure in the vacuum vessel, isolating the pumping unit from the vessel is not applicable...
Cornea transplantation surgery needs a highly skilled ophthalmologist due to the requirement of precise positioning and the plasticity of a cornea. In this paper, we propose a cornea holding device, which fixes the relative position between a donor cornea and a patient cornea. The proposed device prevents the slipping or deformation of the corneas during transplantation surgery. The cornea holder...
This paper proposes a robust chattering-free sliding-mode (CFSM) control for an electronic throttle (ET) system in drive-by-wire vehicles. Although boundary layer method is used in traditional linear sliding-mode based-electronic throttle control systems to remove control chattering, both the tracking precision and control robustness are affected. The uniqueness of the proposed CFSM controller is...
With the continuous expansion of flight envelope about aero-engine, the control range and accuracy of the fuel are increasing. However, the traditional way is difficult to take into account the fuel metering accuracy and response rate, it is necessary for the fuel metering device to have a further study. Through the study of the dual variable control about fuel flow area and pressure-drop, a higher...
In order to ensure the effective operation of condensing steam turbine, a vacuum control method with double compensation loops is developed to solve the problem of condenser vacuum. Firstly, the system identification is carried out according to the measured data of the condenser, and the mathematical model for the condenser vacuum pressure, the flow rate of circulating water and the regulating valve...
Subsea production system is a key technique in the development of oceanic oil/gas resources, which has experienced a long-time evolution. Control system is the core technique of subsea production system, which is indispensable in subsea production. We introduce eight typical control architectures of different structures, including direct hydraulic control system, piloted hydraulic control system,...
Based on the working principle of the electrohydraulic proportional control system of the working device of the demolition robot, the co-simulation model of the system is established by means of ADAMS and MATLAB. The study of the dynamic characteristics of the system was done, with applying traditional PID control strategy and sliding mode variable structure control respectively, considering the change...
To diagnose the specific reasons that lead to deterioration of controller performance and improve the diagnostic accuracy, a performance diagnosis method based on eigenvector subspace K-mean clustering is proposed. Firstly, the number of standard deterioration performance subspace with different degrees of deterioration information is increased on the basis of the eigenvector subspace distance diagnosis...
As strongly nonlinear, dynamic, multidimensional and large scale systems, power systems in operation are always influenced by the external and internal disturbances; and thus the serious threat to stable operation of systems exists. In this paper, based on the three order mathematical model of single machine infinite systems with valve control and under the conditions that systems have unknown damping...
This paper concerns the problem of operating region enlargement for centrifugal pumps. A hybrid management system is described, which combines both the valve throttling and the pump speed adjustment at variable consumer's demands and piping conditions. Solution of the consumed power minimization problem is found and realized with the flexible energy management controller-oriented software. To provide...
Nowadays, the number of divers who want to practice the activity at technical level grows more and more. The Rebreather apparatus can be used to carry out such an experience. This underwater breathing equipment seems to be a complex system, but it is based on a very simple concept: the reuse of the exhaled gas. This apparatus is controlled by an electronic system, a specialized dive computer, that...
Model of a 300MW thermal power unit's governing system of steam turbine was established to analyze its load fluctuation during main steam valve activity test. The model contains three sub-models. They are model of turbine's governor during main steam valve activity test, model of governing valve, model of steam turbine considering governing valve's discharge characteristic. Based on the established...
The purposes of this study were to implement the automatic control EC and pH system in reservoir. The automatic control system operate when get signal output from micro-controller. For micro-controller implement EC and pH adjusting equation that were applied from linear regression. The reason to use linear regression because of in experiment amount of A&B solution or nitric acid that adding to...
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