Design and Test of Motor Double Fed Speed Regulating System for Conveyer Belt

This paper introduces the design of doubly fed system for conveyor belt motor, the system adopts stator flux orientation vector control technology and AC-AC inverter motor speed and power factor control, and carried on the test in transmission field. This paper introduces in detail the structure and characteristic of DSP system, and gives a design scheme of Doubly Fed Speed Control System of motor based on this chip.

The research of power saving frequency conversion speed regulation experiment system

A power saving frequency difference controlling method was introduced by the double inverter and motor experiment system.The characters of the system under differ- ent loads were investigated.The theoretical analysis and experiment results show the frequency difference method is a ideal power saving speed regulation method for the dou- ble inverter and motor system.The experiment system is simply structured,convenient to operate and provides a new way of character testing for frequency conversion speed regulation.

Speed Regulation Method Using Genetic Algorithm for Dual Three-phase Permanent Magnet Synchronous Motors

Dual three-phase Permanent Magnet Synchronous Motor(DTP-PMSM)is a nonlinear,strongly coupled,high-order multivariable system.In today’s application scenarios,it is difficult for traditional PI controllers to meet the requirements of fast response,high accuracy and good robustness.In order to improve the performance of DTP-PMSM speed regulation system,a control strategy of PI controller based on genetic algorithm is proposed.Firstly,the basic mathematical model of DTP-PMSM is established,and the PI parameters of DTP-PMSM speed regulation system are optimized by genetic algorithm,and the modeling and simulation experiments of DTP-PMSM control system are carried out by MATLAB/SIMULINK.The simulation results show that,compared with the traditional PI control,the proposed algorithm significantly improves the performance of the control system,and the speed output overshoot of the GA-PI speed control system is smaller.The anti-interference ability is stronger,and the torque and double three-phase current output fluctuations are smaller.

The Applications of High-voltage variable frequency speed regulation System in Main Exhauster of Sintering

Main Exhauster is one of the main equipment of sintering production. It needs to consume a lot of electricity. Therefore, the system＇ s reconstruction for energy-saving will effectively reduce electricity for the production. The paper takes an iron and steel enterprise that had successfully transformed the synchronous motors of main exhauster of sintering as an example, which describes the application of high-voltage variable frequency speed regulation system in main exhauster of Sintering, so as to provide a reference for other iron and steel enterprises.

Study on Steering Control Strategy for High-Speed Tracked Vehicle with Hydrostatic Drive

Steering control strategy for high-speed tracked vehicle with hydrostatic drive is designed based on analyzing the fundamental steering theories of the hydrostatic drive tracked vehicle. The strategy is completed by the cooperation between integrated steering control unit and pump ＆ motor displacement controller. The steering simulation is conducted by using Simulink of Matlab. It is indicated that this steering control strategy can reduce the average vehicle speed automatically to achieve the driver＇s expected steering radius exactly in the case of en- suring not exceeding the system pressure threshold and no sideslip.

A Model-Based Unmatched Disturbance Rejection Control Approach for Speed Regulation of a Converter-Driven DC Motor Using Output-Feedback

The speed regulation problem with only speed measurement is investigated in this paper for a permanent magnet direct current(DC)motor driven by a buck converter.By lumping all unknown matched/unmatched disturbances and uncertainties together,the traditional active disturbance rejection control(ADRC)approach provides an intuitive solution for the problem under consideration.However,for such a higher-order disturbed system,the increase of poles for the extended state observer(ESO)therein will lead to drastically growth of observer gains,which causes severe noise amplification.This paper aims to propose a new model-based disturbance rejection controller for the converter-driven DC motor system using output-feedback.Instead of estimating lumped disturbances directly,a new observer is constructed to estimate the desired steady state of control signal as well as errors between the real states and their desired steady-state responses.Thereafter,a controller with only speed measurement is proposed by utilizing the estimates.The performance of the proposed method is tested through experiments on dSPACE.It is further shown via numerical calculations and experimental results that the poles of the observer within the proposed control approach can be largely increased without significantly increasing magnitude of the observer gains.

DC Motor Speed Regulator via Active Damping Injection and Angular Acceleration Estimation Techniques

This paper suggests a novel model-based nonlinear DC motor speed regulator without the use of a current sensor.The current dynamics,machine parameters and mismatched load variations are considered.The proposed controller is designed to include an active damping term that regulates the motor speed in accordance with the first-order low-pass filter dynamics through the pole-zero cancellation.Meanwhile,the angular acceleration and its reference are obtained from simple first-order estimators using only the speed information.The effectiveness is experimentally verified using hardware comprising the QUBEServo2,myRIO-1900,and LabVIEW.

A Graded Speed Control Method for Cyborg Rats Based on Electrical Stimulation of the Cuneiform Nucleus

The precise movement speed regulation is a key factor to improve the control effect and efficiency of the cyborg rats.However,the current stimulation techniques cannot realize the graded control of the speed.In this study,we achieved the multi-level speed regulation of cyborg rats in the large open field and treadmill by specifically targeting the Cuneiform Nucleus(CnF)of the Mesencephalic Locomotor Region(MLR).Detailed,we measured the influence of each stimulation parameter on the speed control process which included the real-time speed,accelerated speed,response time,and acceleration period.We concluded that the pulse period and the pulse width were the main determinants influencing the accelerated speed of cyborg rats.Whereas the amplitude of stimulation was found to affect the response time exhibited by the cyborg rats.Our study provides valuable insights into the regulation of rat locomotion speed and highlights the potential for utilizing this approach in various experimental settings.

Research on the soft start-up performance of hydro-viscous drive

The principle and structure of hydro-viscous drive(HVD) set is introduced. Through theoretical analysis of the HVD set start-up steadiness, the conclusions were obtained that the non-linearity of the pressure performance curve and dynamic pressure instability of the pilot-operated electro-hydraulic pressure relief valve, which is used for the HVD speed regulating purpose and usually works within micro flow-rate and low oil pressure state, are the main causes of the poor start-up steadiness. So a special speed regulating valve for HVD set is developed, with which the start-up steadiness of HVD set is much improved.

Model of tri-sectional wheel-based cable climbing robot and analysis of centrifugal safety landing method

This paper proposes a new type of tri-sectional wheel-based cable climbing robot which is able to climb up vertical cylindrical cables of a cable-stayed bridge. The robot is composed of three pairs of wheels equally spaced circularly which are joined by six connecting boards to form a whole closed hexagonal body to clasp a cable. The whole design is entirely modular to enable to assenably the robot on-siteeasy eaoily. To analyze the static features of the robot, a mathematical model of climbing is deduced. Furthermore, taking a cable with a diameter of 80mm as an example, we calculate the design parameters of the robot. For safly landing in the case of electrical accident, a centrifugal speed regulator is proposed and applied to consume useless energy generated when the robot is slipping down along the cables. A simplified mathematical model of the landing mechanism is deduced. Finally, several experiments on the climbing mechanism demonstrate that the robot can carry payloads less than 2.2kg to climb up a cable with diameters varying from 65mm to 205mm.

＂One-for-several＂ rotor VVVF Technique apply to water injection station

In the process of oilfield water injection volume of injection allocation often appear with the pump displacement situation does not match, the widespread adoption of stator frequency technology allows the pump displacement and volume of injection allocation phase matching. But the technology in pump class load application speed range is limited, there is still a reflux valve control blind area,＂ turn off undead＂ problem. ＂ One-for-several＂ rotor frequency Technique in water injection station application, solved the control blind area problem, the full realization of the variable frequency close return voltage injection, at the same time, the successful implementation of the slip power efficient feedback. Stable water injection pressure of the system, and the electric energy is saved, satisfy the oilfield high efficiency, fine water needs, has a high application value.

Bioinspired strategies for biomimetic actuators from ultrafast to ultraslow

Motile plant tissues can control their configurations and regulate their motion speed according to their specific requirements,which offer various protypes for biomimetic actuators with controlled motion speed.In this perspective,we focus on the speed control of plant tissues and the bioinspired strategies for speed regulation of artificial actuators.We begin with a summary to the strategies and mechanisms of motile plant tissues for controlling motion speed,ranging from ultrafast to ultraslow.We then exemplify the models for fabricating bioinspired artificial actuators and briefly discuss current application scenarios of actuators with varying speeds from ultrafast to ultraslow.Finally,we propose potential strategies for the speed regulation of actuators.

Development and experiment of rice hill-drop drilling machine for dry land based on proportional speed regulation

Rice precision hill-drop drilling technique in dry land uses fixed hill spacing to achieve orderly planting of crops and to attain good ventilating and day-lighting effects in rice fields.The technique is also beneficial in improving root growth and root structure and in increasing lodging resistance.The high-yield record of Xinjiang Production and Construction Corp’s first division for three consecutive years shows that rice precision hill-drop drilling technique in dry land is one of the important directions to developed rice cultivating mechanization technology.To further improve the quality of rice precision hill-drop drilling machine for dry land,a single profiling,electro-hydraulic proportional real-time adjustment of system was developed according to the agronomic requirements.This machine can simultaneously finish various kinds of seedbed leveling,furrowing and seeding operations,as well as soil covering and pressing.Electro-hydraulic proportional speed regulation makes an AMESim simulation test and analyzes the stability and error of hydraulic adjusting planting distance.Bench testing was carried out on the metering device by simultaneously employing high speed photography technology and analyzing the relationship of the high speed of hill distance and seed charge height.Finally,machine trial was completed.The two-year field experiments of Xinjiang Production and Construction Corp showed that when the machine operation speed is 2.8-3.2 km/h,the sowing depth percent of pass is 75%or higher,the qualified rate of row spacing is 80%or more,the pass rate of row spacing is 90%or higher,and the quantity per hill is 75%or higher.This machine met the various indicators of hill sowing quality requirements.

GATE REGULATION SPEED AND TRANSITION PROCESS OF UNSTEADY FLOW IN CHANNEL

The operation methods of channel and the speed of gate regulation have great influence on the transformation of flow in water conveyance channels. Based on characteristics method, a 1-D unsteady flow numerical model for gate regulation was established in this study. The process of water flow was simulated under different boundary conditions. The influence of gate regulation speed and channel operation methods on flow transition process was analyzed. The numerical results show that under the same conditions, with increasing regulation speed of the gate, the change rates of discharge and water level increase, while the response time of channel becomes shorter, and ultimately the discharge and water level will transit to the same equilibrium states. Moreover, the flow is easier to reach stable state, if the water level in front of the sluice is kept constant, instead of,behind the sluice. This study will be important to the scheme design of automatic operation control in water conveyance channels.

Fractional-order Sliding Mode Control of Hybrid Drive Wind Turbine for Improving Low-voltage Ride-through Capacity

A hybrid drive wind turbine equipped with a speed regulating differential mechanism can generate electricity at the grid frequency by an electrically excited synchronous generator without requiring fully or partially rated converters. This mechanism has extensively been studied in recent years. To enhance the transient operation performance and low-voltage ridethrough capacity of the proposed hybrid drive wind turbine, we aim to synthesize an advanced control scheme for the flexible regulation of synchronous generator excitation based on fractional-order sliding mode theory. Moreover, an extended state observer is constructed to cooperate with the designed controller and jointly compensate for parametric uncertainties and external disturbances. A dedicated simulation model of a 1.5 MW hybrid drive wind turbine is established and verified through an experimental platform. The results show satisfactory model performance with the maximum and average speed errors of 1.67% and 1.05%, respectively. Moreover, comparative case studies are carried out considering parametric uncertainties and different wind conditions and grid faults, by which the superiority of the proposed controller for improving system ongrid operation performance is verified.

A Power Allocation Method for Grid-Connected MMC Inverter Based on Droop Control

Droop control has been widely used for controlling distributed generators.As capacity of the MMC inverter may be insufficient,a power allocation method for grid-connected MMC inverter based on droop control is presented to improve the stability of the power system.As there is potential for large disturbances in the power grid,an equal speed regulation strategy is adopted to make the speed of the voltage collapse be the same as the frequency collapse.With obtaining the active and reactive power references of MMC inverter according to equal speed regulation strategy,the deadbeat control method is calculated using these power references and adopted to track the reference currents.The Routh criterion is used to analyze the influence of the inductance measurement error on the control system.Additionally,a simulation model is established with Matlab and Simulink.The simulation results show that the stability of the power grid has been improved with the proposed control method.