The Variable PWM Frequency Control Research for the Motor in Wheel

2014 ◽  
Vol 496-500 ◽  
pp. 1352-1355
Author(s):  
Chuan Xue Song ◽  
Si Lun Peng ◽  
Shi Xin Song ◽  
Jian Hua Li ◽  
Zhu'an Zheng
Keyword(s):  
Motor Control ◽  
Control Strategy ◽  
Frequency Control ◽  
Torque Ripple ◽  
Control Model ◽  
Low Speed ◽  
Control Research ◽  
The Impact

According to the characteristics that the motor in wheel is insensitivity of torque ripple, the impact of reducing PWM frequency on motor control is studied, and the phenomenon that the PWM frequency is limited by the lag angle of motor commutation. Then a variable PWM frequency control strategy according to rotate speed is proposed. Based on Simulink, the motor control model is built and the control strategy is verified by simulation. The result shows that the variable PWM frequency control significantly improves the performance of motor at low speed, with little toque ripple increased.

Dual Clutch Automatic Transmission Two Clutch Starting Control and Simulation

2013 ◽  
Vol 372 ◽  
pp. 538-542
Author(s):  
Guo Zhong Jia ◽  
Xin Ping Wu ◽  
Zhen Hua Jia
Keyword(s):  
Simulation Model ◽  
Control Strategy ◽  
Control Strategies ◽  
Automatic Transmission ◽  
Control Model ◽  
Launch Strategy ◽  
Simulation Results ◽  
Clutch Control ◽  
The Impact ◽  
Starting Control

According to the special structure of DCT, the control strategy of launch with two clutches has been proposed to share the friction work and extend the life of both clutches. The dynamic model of launch with two clutches and the clutch control model have been built. the control strategies of both clutches have been proposed respectively according to the requirement of the different driver intention and the limitation of the impact of vehicle. The simulation model of launch with two clutches has been built using the Matlab/Simulink platform, and the simulation has been carried out. The Simulation results show that the balance of friction work based on this launch strategy with two clutches has been validated.

A Direct Torque Control Driven Vessel Actuator Device

2014 ◽  
Vol 651-653 ◽  
pp. 593-597
Author(s):  
Hui Lue Jiang ◽  
Bo Liu ◽  
Chuan Dao Liu
Keyword(s):  
Dynamic Performance ◽  
Complex Structure ◽  
Direct Torque Control ◽  
Torque Ripple ◽  
Torque Control ◽  
Low Speed ◽  
Simulation Results ◽  
Low Efficiency ◽  
The Impact

Actuator is one of the most important auxiliary mechanisms used to control the ship heading. Focused on the existed shortages of conventional hydraulic driven vessel actuator as complex structure, low efficiency and response etc, by the analysis of torque variation to access the impact of direct torque control and design an actuator used direct torque control of which is simple and easy to implement. Simulation results show that this scheme can reduce system without dynamic performance, low-speed operation to expand the scope of the system, reducing the torque ripple, while improving the low-speed torque of the motor.

scholarly journals Coil Number Impact on Performance of 4-Phase Low Speed Toothed Doubly Salient Permanent Magnet Motors

Machines ◽  
2021 ◽  
Vol 9 (7) ◽  
pp. 137
Author(s):  
Cherif Guerroudj ◽  
Jean-Frederic Charpentier ◽  
Rachid Saou ◽  
Yannis L. Karnavas ◽  
Nicolas Bracikowski ◽  
...  
Keyword(s):  
Permanent Magnet ◽  
High Power ◽  
Structural Parameters ◽  
Torque Ripple ◽  
Energy Ratio ◽  
Direct Drive ◽  
Low Speed ◽  
Ship Propulsion ◽  
Doubly Salient ◽  
The Impact

The low speed toothed doubly salient permanent-magnet (TDSPM) machine is an interesting candidate motor for electric ship applications because, of its high torque output, maintenance-free operation and flexible working modes, which gives the opportunity to increase system’s reliability, and decrease the system size, weight and noise which are key features for naval applications. However, particularly in the 3-phase configuration, the stator and rotor saliency of these machines leads to a high level of torque ripple. To overcome these drawbacks, the use of polyphase machines (with a number of phases greater than three) can be a relevant solution. In this paper, an optimal design of two kind of novel 4-phase motors is performed in order to fulfil the specifications of a high power naval ship propulsion. The designs aim to maximize the torque to mass ratio. The motors’ performances are directly linked to their structural parameters, so, the impact of the coil number in terms of mean torque, torque ripple, energy ratio values, and efficiency is also presented and analysed. The design of these two electromagnetic structures, as well as the determination of their electromagnetic performances, are carried out using a particle swarm optimization algorithm (PSO) with taking into account thermal constraint. The performance of the proposed machine in terms of mean torque, torque ripple, energy ratio, and efficiency values is presented and analysed. The results obtained reveal that the TDSPM machines with four poles/phase are good candidates to meet the requirements of high power direct-drive ship propulsion system.

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.

Sign in / Sign up

Export Citation Format

Share Document