A Compensation Approach of Backlash Nonlinearity in Dual-Motor Driving Servo System

2013 ◽  
Vol 389 ◽  
pp. 448-453
Author(s):  
Hai Bo Zhao ◽  
Yun Guo Zhu
Keyword(s):  
Control Strategy ◽  
Linear Part ◽  
Servo System ◽  
Step Response ◽  
Compensation Control ◽  
Speed Tracking ◽  
Compensation Approach ◽  
The Impact ◽  
Backlash Nonlinearity ◽  
Nonlinearity Characteristic

Aiming at the control problem of dual-motor driving servo system with backlash nonlinearity, we proposed the model of system linear part. We used describing function methods to analyze backlash nonlinearity characteristic. The simulation experiments of nonlinear system with backlash were carried out. The results of simulation show that system represents residual self-oscillation with step response, nonstationarity with low speed tracking and error abrupt change produced by sinusoidal tracking reversing. In the end, we used compensation control strategy to weaken the impact of backlash nonlinearity on dual-motor driving servo system. Finally the simulation illustrates the effectiveness of the proposed compensation control strategy.

A Compensation Approach of Dead-Zone Nonlinearity in Dual-Motor Driving Servo System

2013 ◽  
Vol 389 ◽  
pp. 454-459 ◽  
Author(s):  
Hai Bo Zhao ◽  
Yun Guo Zhu
Keyword(s):  
Nonlinear System ◽  
Control Strategy ◽  
Dead Zone ◽  
Servo System ◽  
Step Response ◽  
Describing Function ◽  
Simulation Experiments ◽  
Compensation Control ◽  
Compensation Approach ◽  
The Impact

Aiming at the control problem of dual-motor driving servo system with dead-zone nonlinearity,we proposed the model of system linear part.We used describing function methods to analyze dead-zone nonlinearity characteristic.The simulation experiments of nonlinear system with dead-zone were carried out.The results of simulation show that system represents the phenomenon of zero deflection with step response,error curve exists peak at commutation time with sine response.In the end,we used compensation control strategy to weaken the impact of dead-zone nonlinearity on dual-motor driving servo system.Finally the simulation illustrates the effectiveness of the proposed compensation control strategy.

The Position Servo Control Strategy of High Dynamic Response Based on Electric Steering Gear

2013 ◽  
Vol 310 ◽  
pp. 524-531
Author(s):  
Guo Ping Zhao ◽  
Hong Xing Wu ◽  
Min Xiu Kong ◽  
Li Yi Li
Keyword(s):  
Vector Control ◽  
Control Strategy ◽  
Servo System ◽  
Current Loop ◽  
Feed Forward ◽  
Loop Control ◽  
Feed Forward Control ◽  
High Dynamic ◽  
Position Servo ◽  
The Impact

This paper studies the current loop, velocity loop and position loop controller of PMSM position servo system for Electric steering gear servo system. It makes research around the principle of PMSM vector control and three control loop control strategy. The control strategy bases on the principle of vector control of PMSM when id=0 and uses the classic PI control theory. A new method of decouple control for the current of direct axis and cross axis direct is presented. It will overcome the impact of EMF when the motor is working in high dynamic. The system uses the feed-forward control to compensate the position deviation of permanent magnet synchronous motor using in the steering gear. The paper also researches transfer function of feed-forward control of the location, and establishes the feed-forward controller model of the position loop. Simulation results demonstrate the effectiveness of our proposed scheme.

scholarly journals Onchocerciasis control in Ghana (1974–2016)

2021 ◽  
Vol 14 (1) ◽  
Author(s):  
Nana-Kwadwo Biritwum ◽  
Dziedzom K. de Souza ◽  
Odame Asiedu ◽  
Benjamin Marfo ◽  
Uche Veronica Amazigo ◽  
...  
Keyword(s):  
Confidence Interval ◽  
Vector Control ◽  
Control Strategy ◽  
Financial Support ◽  
Control Programme ◽  
Ivermectin Treatment ◽  
Mobile Community ◽  
The Mean ◽  
The Impact ◽  
Onchocerciasis Control

Abstract Background The control of onchocerciasis in Ghana started in 1974 under the auspices of the Onchocerciasis Control Programme (OCP). Between 1974 and 2002, a combination of approaches including vector control, mobile community ivermectin treatment, and community-directed treatment with ivermectin (CDTI) were employed. From 1997, CDTI became the main control strategy employed by the Ghana OCP (GOCP). This review was undertaken to assess the impact of the control interventions on onchocerciasis in Ghana between 1974 and 2016, since which time the focus has changed from control to elimination. Methods In this paper, we review programme data from 1974 to 2016 to assess the impact of control activities on prevalence indicators of onchocerciasis. This review includes an evaluation of CDTI implementation, microfilaria (Mf) prevalence assessments and rapid epidemiological mapping of onchocerciasis results. Results This review indicates that the control of onchocerciasis in Ghana has been very successful, with a significant decrease in the prevalence of infection from 69.13% [95% confidence interval) CI 60.24–78.01] in 1975 to 0.72% (95% CI 0.19–1.26) in 2015. Similarly, the mean community Mf load decreased from 14.48 MF/skin snip in 1975 to 0.07 MF/skin snip (95% CI 0.00–0.19) in 2015. Between 1997 and 2016, the therapeutic coverage increased from 58.50 to 83.80%, with nearly 100 million ivermectin tablets distributed. Conclusions Despite the significant reduction in the prevalence of onchocerciasis in Ghana, there are still communities with MF prevalence above 1%. As the focus of the GOCP has changed from the control of onchocerciasis to its elimination, both guidance and financial support are required to ensure that the latter goal is met.

scholarly journals Evaluation of P-Band SAR Tomography for Mapping Tropical Forest Vertical Backscatter and Tree Height

2021 ◽  
Vol 13 (8) ◽  
pp. 1485
Author(s):  
Naveen Ramachandran ◽  
Sassan Saatchi ◽  
Stefano Tebaldini ◽  
Mauro Mariotti d’Alessandro ◽  
Onkar Dikshit
Keyword(s):  
Tropical Forest ◽  
Vertical Profile ◽  
Mean Squared Error ◽  
Low Frequency ◽  
Tree Height ◽  
Canopy Layer ◽  
Local Maxima ◽  
Slope Correction ◽  
Compensation Approach ◽  
The Impact

Low-frequency tomographic synthetic aperture radar (TomoSAR) techniques provide an opportunity for quantifying the dynamics of dense tropical forest vertical structures. Here, we compare the performance of different TomoSAR processing, Back-projection (BP), Capon beamforming (CB), and MUltiple SIgnal Classification (MUSIC), and compensation techniques for estimating forest height (FH) and forest vertical profile from the backscattered echoes. The study also examines how polarimetric measurements in linear, compact, hybrid, and dual circular modes influence parameter estimation. The tomographic analysis was carried out using P-band data acquired over the Paracou study site in French Guiana, and the quantitative evaluation was performed using LiDAR-based canopy height measurements taken during the 2009 TropiSAR campaign. Our results show that the relative root mean squared error (RMSE) of height was less than 10%, with negligible systematic errors across the range, with Capon and MUSIC performing better for height estimates. Radiometric compensation, such as slope correction, does not improve tree height estimation. Further, we compare and analyze the impact of the compensation approach on forest vertical profiles and tomographic metrics and the integrated backscattered power. It is observed that radiometric compensation increases the backscatter values of the vertical profile with a slight shift in local maxima of the canopy layer for both the Capon and the MUSIC estimators. Our results suggest that applying the proper processing and compensation techniques on P-band TomoSAR observations from space will allow the monitoring of forest vertical structure and biomass dynamics.

scholarly journals Optimal Fractional-Order Active Disturbance Rejection Controller Design for PMSM Speed Servo System

Entropy ◽  
2021 ◽  
Vol 23 (3) ◽  
pp. 262
Author(s):  
Pengchong Chen ◽  
Ying Luo ◽  
Yibing Peng ◽  
Yangquan Chen
Keyword(s):  
Fractional Order ◽  
Disturbance Rejection ◽  
Pid Controller ◽  
External Disturbance ◽  
Servo System ◽  
Stable Region ◽  
Speed Tracking ◽  
Active Disturbance Rejection ◽  
Load Disturbance ◽  
Tuning Strategy

In this paper, a fractional-order active disturbance rejection controller (FOADRC), combining a fractional-order proportional derivative (FOPD) controller and an extended state observer (ESO), is proposed for a permanent magnet synchronous motor (PMSM) speed servo system. The global stable region in the parameter (Kp, Kd, μ)-space corresponding to the observer bandwidth ωo can be obtained by D-decomposition method. To achieve a satisfied tracking and anti-load disturbance performance, an optimal ADRC tuning strategy is proposed. This tuning strategy is applicable to both FOADRC and integer-order active disturbance rejection controller (IOADRC). The tuning method not only meets user-specified frequency-domain indicators but also achieves a time-domain performance index. Simulation and experimental results demonstrate that the proposed FOADRC achieves better speed tracking, and more robustness to external disturbance performances than traditional IOADRC and typical Proportional-Integral-Derivative (PID) controller. For example, the JITAE for speed tracking of the designed FOADRC are less than 52.59% and 55.36% of the JITAE of IOADRC and PID controller, respectively. Besides, the JITAE for anti-load disturbance of the designed FOADRC are less than 17.11% and 52.50% of the JITAE of IOADRC and PID controller, respectively.

scholarly journals Quadrature Voltage Compensation in the Isolated Multi-Modular Converter

Energies ◽  
2021 ◽  
Vol 14 (3) ◽  
pp. 529
Author(s):  
Cristian Verdugo ◽  
Jose Ignacio Candela ◽  
Pedro Rodriguez
Keyword(s):  
Control Strategy ◽  
Phase Voltage ◽  
Multilevel Converters ◽  
Photovoltaic Panels ◽  
Circulating Current ◽  
Three Phase ◽  
Voltage Compensation ◽  
Wide Range ◽  
Modular Converter ◽  
The Impact

Series connections of modules in cascaded multilevel converters are prone to power imbalances due to voltage differences on their DC side. When modules are connected to direct current (DC) sources, such as photovoltaic panels, the capability of withstanding power imbalances is crucial for generating the maximum power. In order to provide a possible solution for this requirement, this paper proposes a control strategy called Quadrature Voltage Compensation, which allows a wide range of power imbalances. The proposed control strategy regulates the power by introducing a circulating current between the arms and a phase angle in the output voltage. The impact of the circulating current and its effect on the phase voltage are studied. To highlight the features of the proposed strategy, an analytical model based on vector superposition is also described, demonstrating the strong capability of tolerating power differences. Finally, to validate the effectiveness of the Quadrature Voltage Compensation, simulation and experimental results are presented for a three-phase isolated multi-modular converter.

Experimental Investigation on Improving Electromechanical Impedance Based Damage Detection by Temperature Compensation

2013 ◽  
Vol 569-570 ◽  
pp. 1132-1139 ◽  
Author(s):  
Thomas Siebel ◽  
Mihail Lilov
Keyword(s):  
Damage Detection ◽  
Structural Damage ◽  
Temperature Compensation ◽  
Impact Damage ◽  
Correlation Coefficients ◽  
Electromechanical Impedance ◽  
Reinforced Plastic ◽  
Influence Of Temperature On ◽  
Compensation Approach ◽  
The Impact

The sensitivity of the electromechanical impedance to structural damage under varying temperature is investigated in this paper. An approach based on maximizing cross-correlation coefficients is used to compensate temperature effects. The experiments are carried out on an air plane conform carbon fiber reinforced plastic (CFRP) panel (500mm x 500mm x 5mm) instrumented with 26 piezoelectric transducers of two different sizes. In a first step, the panel is stepwise subjected to temperatures between-50 °C and 100 °C. The influence of varying temperatures on the measured impedances and the capability of the temperature compensation approach are analyzed. Next, the sensitivity to a 200 J impact damage is analyzed and it is set in relation to the influence of a temperature change. It becomes apparent the impact of the transducer size and location on the quality of the damage detection. The results further indicate a significant influence of temperature on the measured spectra. However, applying the temperature compensation algorithm can reduce the temperature effect at the same time increasing the transducer sensitivity within its measuring area. The paper concludes with a discussion about the trade-off between the sensing area, where damage should be detected, and the temperature range, in which damage within this area can reliably be detected.

Sign in / Sign up

Export Citation Format

Share Document