Within the framework of the article, the improved method effectiveness of controlling the electric mode of the shaft-type electric arc furnace SF-125 is considered and substantiated, which takes into account the data ...
详细信息
ISBN:
(数字)9781728162300
ISBN:
(纸本)9781728162317
Within the framework of the article, the improved method effectiveness of controlling the electric mode of the shaft-type electric arc furnace SF-125 is considered and substantiated, which takes into account the data about harmonic composition of the electric arc voltage. The basic principle of this method is to diagnose the stage of melting the charge in accordance with a parameter that has a direct relationship with the actual physical processes taking place inside the furnace bath. Due to this, a timely transition from one combination of the furnace transformer step and the number of the operating curve to another is achieved in accordance with a given melting profile, which in turn allows increasing the total efficiency of the metallurgical by reducing the specific power consumption and operating time under current.
The full duplex (FD) communication means that transmits and receives data simultaneously in the same frequency. Due to this, the FD communication is more affected by interference. In the FD communication, transmission...
详细信息
ISBN:
(数字)9781728162898
ISBN:
(纸本)9781728162904
The full duplex (FD) communication means that transmits and receives data simultaneously in the same frequency. Due to this, the FD communication is more affected by interference. In the FD communication, transmission signal of node might be interference to other nodes. If the distance between the nodes is not far enough, the FD communication is impossible. Therefore, we propose the power control algorithm for the FD communication. If the distance between the nodes is close, the transmission power should be controlled to reduce interference. To evaluate our proposed algorithm, we conduct simulation. The results show that the throughput of proposed algorithm is higher than conventional algorithm and power consumption of proposed algorithm is lower than conventional algorithm.
Based on the medium-low speed maglev vehicle with mid-set air spring, the dynamic model with three levitation frames are established in UM (Universal Mechanism). The performance of the vehicle at different speeds is a...
详细信息
ISBN:
(数字)9781728181455
ISBN:
(纸本)9781728181462
Based on the medium-low speed maglev vehicle with mid-set air spring, the dynamic model with three levitation frames are established in UM (Universal Mechanism). The performance of the vehicle at different speeds is analyzed. The results show that the dynamic performance can meet the requirements of the maglev vehicle running at higher speeds. However, the magnet current also increases with the increase of running speed, which leads to an increase in the weight of the magnet and the controller, and then the drive unit of maglev vehicle becomes heavier. Then three types of levitation control algorithms are established in MATLAB/Simulink: PID feedback control, PI+P hybrid control, PID+fuzzy control. For the optimization of magnet current, the control performance of the maglev vehicle to the track excitation under different levitation control algorithms is analyzed. The following conclusions can be drawn: on the basis of keeping the suspension stability, different levitation control algorithms have different magnet current responses with same running speed and vehicle parameters. PID+fuzzy control can effectively lower the magnet current fluctuation and reduce the r.m.s. value of magnet current; PI+P hybrid control can effectively decline the impact of mutation interference on the current and reduce the current fluctuation range.
A nonlinear optimal (H-infinity) control approach is developed for the model of the ballbot. This robotic system consists of a rolling sphere with a rigid body, in the form of an inverted pendulum, mounted on top of t...
详细信息
ISBN:
(数字)9781538682661
ISBN:
(纸本)9781538682678
A nonlinear optimal (H-infinity) control approach is developed for the model of the ballbot. This robotic system consists of a rolling sphere with a rigid body, in the form of an inverted pendulum, mounted on top of the sphere. Because of the nonlinearities and underactuation that are due to the dynamics of both the rolling sphere and of the rotational motion of the rigid body, control of the ballbot is a non-trivial problem. In the proposed control method, the dynamic model of the ballbot undergoes first approximate linearization around a temporary operating point which is updated at each iteration of the control algorithm. The linearization process makes use of first-order Taylor series expansion and relies also on the computation of the Jacobian matrices of the state-space model of the robotic system. A stabilizing H-infinity feedback controller is designed for the approximately linearized description of the ballbot. An algebraic Riccati equation is solved at each time-step of the control method so as to compute the controller's feedback gains. Through Lyapunov analysis the stability properties of the control scheme are proven. Besides, through the article's results it is demonstrated that the control method retains the advantages of linear optimal control, that is fast and accurate tracking of the reference setpoints under moderate variations of the control inputs.
This paper presents a control algorithm for the full H-bridge inverter that tracks with arbitrary small precision a given desired sinusoidal reference trajectory. The proposed control algorithm is hybrid and predictiv...
详细信息
ISBN:
(数字)9781538682661
ISBN:
(纸本)9781538682678
This paper presents a control algorithm for the full H-bridge inverter that tracks with arbitrary small precision a given desired sinusoidal reference trajectory. The proposed control algorithm is hybrid and predictive in nature. It consists in steering a quadratic Lyapunov function of the tracking errors towards an arbitrarily small value. In this way, the trajectories of the inverter remain sufficiently close to the reference trajectory. This property is guaranteed in the presence of an unknown resistive load through the use of a finite-time estimator. Simulations confirm that the proposed algorithm maintains the frequency of the switches within a reasonable range.
Autonomous rendezvous and docking/berthing in presence of two main attracting bodies is considered one of the key operations for future space explorations. Dynamic modeling, and relative guidance and control algorithm...
详细信息
ISBN:
(数字)9781538682661
ISBN:
(纸本)9781538682678
Autonomous rendezvous and docking/berthing in presence of two main attracting bodies is considered one of the key operations for future space explorations. Dynamic modeling, and relative guidance and control algorithms must be designed so as not to compromise the safety of the mission and to provide a collision-free environment. Two of the main approaches to guarantee collision avoidance are a closed loop active control design, and an open loop passive strategy. The paper presents the development of a passive safety procedure based on manifold theory, which provides collision-free trajectory in the presence of specific actuator failures. The proposed procedure is applied to the scenario defined by the European Space Agency Heracles study, for rendezvous in cislunar orbits.
Automotive meets power electronics and IT – designing an automotive On-Board Charger for electrical vehicles requires the convergence of multiple engineering disciplines, to result in a cost-efficient, reliable and s...
详细信息
ISBN:
(纸本)9783800752027
Automotive meets power electronics and IT – designing an automotive On-Board Charger for electrical vehicles requires the convergence of multiple engineering disciplines, to result in a cost-efficient, reliable and safe product for volume manufacturing. Achieving a high power density and electrical efficiency in a small target package implies a complex optimization task of placing all components and their interconnections, given the constraints of their thermal, electromagnetic and isolation needs and impacts. The control logic is based on a multi-processor system, in order to realize not only the vehicle integration, but also fast digital signal processing for the control algorithms, and IP-based protocol stacks for the communications with the charging infrastructure. An increasing demand for cyber-security provisions is driven by the introduction of smart charging features.
Research on ocean current energy power generation equipment based on hydraulic transduction belongs to the scientific and technological frontier of energy equipment development research, which has important theoretica...
详细信息
ISBN:
(数字)9781728190266
ISBN:
(纸本)9781728190273
Research on ocean current energy power generation equipment based on hydraulic transduction belongs to the scientific and technological frontier of energy equipment development research, which has important theoretical significance and huge commercial value. According to the system design requirements, the paper established relevant mathematical models and analyzed the main factors affecting the motor speed, including the mathematical models of variable pumps and variable motors. At the same time, using the AMESim simulation platform, a simulation model that is consistent with the experimental parameters of hydraulic transmission and control power generation is established to establish a theoretical basis for the study of control algorithms. Through the simulation model, the influence of different input and interference signals on the motor speed is analyzed. Combined with the functional requirements of ocean current power generation equipment, the hydraulic conversion control power generation equipment control system was researched and parameter designed. The control system takes variable motor constant speed control as the core and converts the disordered input natural flow energy into hydraulic energy. Adopting feedforward adaptive control algorithm, and using the steeples speed regulation of the hydraulic system, the novel distributed generation system realized the constant frequency power generation of the generator rigidly connected to the hydraulic motor.
According to the characteristic of traffic stream at urban intersections in China, which is uneven, random and complicated, on the one hand, an autonomous optimization control algorithm for traffic signal based on sin...
详细信息
ISBN:
(数字)9781728162836
ISBN:
(纸本)9781728162843
According to the characteristic of traffic stream at urban intersections in China, which is uneven, random and complicated, on the one hand, an autonomous optimization control algorithm for traffic signal based on single signal group was proposed in this paper. By this algorithm, the traffic stream can be controlled independently as the single unit, different combination of green signal can be formed flexibly according to different traffic demand, and the green time for each traffic stream was adjusted dynamically with the consideration of vehicle queue length in all directions of the intersection. On the other hand, based on the development of the open source interface of SUMO, the hardware in-loop simulation system connected to the traffic signal controller and microwave radar detector was established, the status data of the traffic signal and the traffic stream were obtained through the communication interface in real time, the result of autonomous optimization control algorithm was simulated and evaluated online. Finally, a full-day application test was carried out at actual intersection, the test result showed that, compared with the fixed phase actuated control scheme, the vehicle queue length and space occupancy were decreased more effectively by the algorithm proposed in this paper, which can further improve the traffic efficiency at intersection.
In this paper, the Hamilton method is used to establish a distributed parameter model for a single-link flexible robotic arm based on the form of partial differential equations. The distributed parameter system is use...
详细信息
ISBN:
(数字)9781728182889
ISBN:
(纸本)9781728182896
In this paper, the Hamilton method is used to establish a distributed parameter model for a single-link flexible robotic arm based on the form of partial differential equations. The distributed parameter system is used to control the model. The boundary control method is used to add a boundary control input to the end boundary of the manipulator. The PD boundary controller is designed, and the distributed parameter boundary control based on the exponential convergence method is performed on the end boundary of the manipulator to adjust the vibration of the robotic arm. The Lyapunov function is designed to prove the stability of the system through calculation.
暂无评论