scholarly journals Propeller control strategy for coaxial compound helicopters

2018 ◽  
Vol 233 (10) ◽  
pp. 3775-3789 ◽  
Author(s):  
Ye Yuan ◽  
Douglas Thomson ◽  
Renliang Chen
Keyword(s):  
Control Strategy ◽  
High Speed ◽  
High Performance ◽  
Control Strategies ◽  
Flight Dynamics ◽  
Axial Thrust ◽  
Handling Qualities ◽  
Speed Range ◽  
Compound Helicopter ◽  
Flight Dynamics Model

The coaxial compound configuration has been proposed as a concept for future high-performance rotorcraft. The co-axial rotor system does not require an anti-torque device, and a propeller provides axial thrust. A well-designed control strategy for the propeller is necessary to improve the performance and the flight dynamics characteristics. A flight dynamics model of coaxial compound helicopter is developed to analyze these influences. The performance and the flight dynamics characteristics in different propeller strategies were first investigated. The results show that there is an improvement in the performance in high-speed flight when the propeller provides more propulsive forces. It also illustrates that a reasonable allocation of the rotor and the propeller in providing thrust can further reduce the power consumption in the mid speed range. In other words, the propeller control strategy can be an effective method to improve the cruise-efficiency. The flight dynamics analysis in this paper includes trim and handling qualities. The trim results prove that the propeller strategy can affect the collective pitch, longitudinal cyclic pitch, and the pitch attitude. If the control strategy is designed only to decrease the required power, it will result in a discontinuity in the trim characteristics. Handling qualities are investigated based on the ADS-33E-PRF requirement. The result demonstrates that the bandwidth and phase delay results and eigenvalue results in various speed at different propeller strategies are all satisfied. However, some propeller control strategies lead to severe inter-axis coupling in high-speed flight. Based on these results, this paper proposes the propeller control strategy for the coaxial compound helicopter. This strategy ensures good trim characteristics and handling qualities, which satisfy the related requirements, and improves the flight range or the performance in high-speed flight.

scholarly journals Enhancement of Sensorless Control for Non-Sinusoidal Multiphase Drives-Part I: Operation in Medium and High-Speed Range

Energies ◽  
2022 ◽  
Vol 15 (2) ◽  
pp. 607
Author(s):  
Youssouf Mini ◽  
Ngac Ky Nguyen ◽  
Eric Semail ◽  
Duc Tan Vu
Keyword(s):  
Control Strategy ◽  
High Speed ◽  
Sliding Mode ◽  
Sensorless Control ◽  
Control Strategies ◽  
High Accuracy ◽  
Motor Drives ◽  
Synchronous Machines ◽  
Permanent Magnet Synchronous Machines ◽  
Speed Range

This two-part study proposes a new sensorless control strategy for non-sinusoidal multiphase permanent magnet synchronous machines (PMSMs), especially integrated motor drives (IMDs). Based on the Sliding Mode Observer (SMO), the proposed sensorless control strategy uses the signals (currents and voltages) of all fictitious machines of the multiphase PMSMs. It can estimate the high-accuracy rotor positions that are required in vector control. This proposed strategy is compared to the conventional sensorless control strategy that applies only current and voltage signals of the main fictitious machine, including the fundamental component of back electromotive force (back EMF) of non-sinusoidal multiphase PMSMs. Therefore, in order to choose an appropriate sensorless control strategy for the non-sinusoidal multiphase PMSMs, these two sensorless control strategies will be highlighted in terms of precision with respect to rotor position and speed estimation. Simulations and the experimental results obtained with a non-sinusoidal seven-phase PMSM will be shown to verify and compare the two sensorless control strategies. In this part of the study (part I), only sensorless control in the medium and high-speed range is considered. Sensorless control at the zero and low-speed range will be treated in the second part of this study (part II).

scholarly journals Study on High Performance Control of the Machine-Side Converter of Doubly-Fed Turbines under Grid Distortion

2020 ◽  
Vol 185 ◽  
pp. 01060
Author(s):  
Huanruo Qi ◽  
Ningkang Zheng ◽  
Xiangyang Yan ◽  
Yilong Kang
Keyword(s):  
Reference Frame ◽  
Control Strategy ◽  
High Performance ◽  
Control Strategies ◽  
Dynamic Modelling ◽  
Performance Control ◽  
Advantages And Disadvantages ◽  
Current Controller ◽  
Simulation Results ◽  
Doubly Fed

Two control strategies of DFIG under grid distortion are firstly summarized, namely, the control strategy of PI-R current controller based on dq reference frame and the control strategy of PI current controller based on the multiple rotating dq reference frame, and their advantages and disadvantages are analysed. On the basis of dynamic modelling of DFIG under grid distortion, in view of the defect that DFIG coupling is not considered in the control strategy of PI-R current controller based on dq reference frame, an improved control strategy considering motor coupling is proposed. In the end, the modelling and simulation of the unimproved and improved control strategies of PI-R current controller based on dq reference frame are carried out, and the simulation results verified the effectiveness of the improved control strategy.

Modeling and Control of Pantograph and Contact Wire for High Speed Train

2000 ◽  
Author(s):  
Marco Muenchhof ◽  
Timothy Hindle ◽  
Tarunraj Singh
Keyword(s):  
Control Strategy ◽  
High Speed ◽  
Control Strategies ◽  
Optimization Techniques ◽  
High Speed Train ◽  
Modeling And Control ◽  
Contact Wire ◽  
Closed Form Solutions ◽  
Mass Damper ◽  
And Control

Abstract The paper focuses on the modeling and control of a catenary-pantograph system. For the catenary system, only the contact wire is considered. Initially, the case of a constant force traveling at a constant velocity along the wire is investigated and closed form solutions are derived. Next, the pantograph dynamics are considered using a simple spring-mass-damper model, where the force is no longer assumed to be constant. The need for control in this case is apparent and motivates two different control strategies. The first control strategy utilizes a feed-forward Fourier series control profile. For the second control strategy, a proportional force feed-back control is added. All control parameters are obtained using constrained optimization techniques. Stability and sensitivity issues are addressed.

Kinematic Kalman Filter (KKF) for Robot End-Effector Sensing

2009 ◽  
Vol 131 (2) ◽  
Author(s):  
Soo Jeon ◽  
Masayoshi Tomizuka ◽  
Tetsuaki Katou
Keyword(s):  
Kalman Filter ◽  
High Speed ◽  
High Performance ◽  
Control Strategies ◽  
Sampling Rate ◽  
Body Motion ◽  
Vision Sensor ◽  
End Effector ◽  
Measurement Delay ◽  
Velocity Information

In control of industrial manipulators, the position from the motor encoder has been the only sensor measurement for axis control. In this case, it is not easy to estimate the end-effector motion accurately because of the kinematic errors of links, joint flexibility of gear mechanisms, and so on. Direct measurement of the end-effector using the vision sensor is considered as a solution but its performance is often limited by the slow sampling rate and the latency. To overcome these limitations, this paper extends the basic idea of the kinematic Kalman filter (KKF) to general rigid body motion leading to the formulation of the multidimensional kinematic kalman filter (MD-KKF). By combining the measurements from the vision sensor, the accelerometers and the gyroscopes, the MD-KKF can recover the intersample values and compensate for the measurement delay of the vision sensor providing the state information of the end-effector fast and accurately. The performance of the MD-KKF is verified experimentally using a planar two-link robot. The MD-KKF will be useful for widespread applications such as the high speed visual servo and the high-performance trajectory learning for robot manipulators, as well as the control strategies which require accurate velocity information.

High Performance Nonsalient Sensorless BLDC Motor Control Strategy From Standstill to High Speed

2018 ◽  
Vol 14 (10) ◽  
pp. 4365-4375 ◽  
Author(s):  
Xinxiu Zhou ◽  
Xi Chen ◽  
Cong Peng ◽  
Yongping Zhou
Keyword(s):  
Motor Control ◽  
Control Strategy ◽  
High Speed ◽  
High Performance ◽  
Bldc Motor

scholarly journals Variable rotor speed strategy for coaxial compound helicopters with lift–offset rotors

2019 ◽  
Vol 124 (1271) ◽  
pp. 96-120 ◽  
Author(s):  
Y. Yuan ◽  
D. Thomson ◽  
R. Chen
Keyword(s):  
Power Consumption ◽  
High Speed ◽  
High Performance ◽  
Normal Load ◽  
Flight Dynamics ◽  
Load Factor ◽  
Rotor Speed ◽  
Inverse Simulation ◽  
Maneuvering Flight ◽  
The Impact

ABSTRACTThe coaxial compound helicopter with lift-offset rotors has been proposed as a concept for future high-performance rotorcraft. This helicopter usually utilizes a variable-speed rotor system to improve the high-speed performance and the cruise efficiency. A flight dynamics model of this helicopter associated with rotor speed governor/engine model is used in this article to investigate the effect of the rotor speed change and to study the variable rotor speed strategy. Firstly, the power-required results at various rotor rotational speeds are calculated. This comparison indicates that choice of rotor speed can reduce the power consumption, and the rotor speed has to be reduced in high-speed flight due to the compressibility effects at the blade tip region. Furthermore, the rotor speed strategy in trim is obtained by optimizing the power required. It is demonstrated that the variable rotor speed successfully improves the performance across the flight range, but especially in the mid-speed range, where the rotor speed strategy can reduce the overall power consumption by around 15%. To investigate the impact of the rotor speed strategy on the flight dynamics properties, the trim characteristics, the bandwidth and phase delay, and eigenvalues are investigated. It is shown that the reduction of the rotor speed alters the flight dynamics characteristics as it affects the stability, damping, and control power provided by the coaxial rotor. However, the handling qualities requirements are still satisfied with different rotor speed strategies. Finally, a rotor speed strategy associated with the collective pitch is designed for maneuvering flight considering the normal load factor. Inverse simulation is used to investigate this strategy on maneuverability in the Push-up & Pull-over Mission-Task-Element (MTE). It is shown that the helicopter can achieve Level 1 ratings with this rotor speed strategy. In addition, the rotor speed strategy could further reduce the power consumption and pilot workload during the maneuver.

Piloted Simulation Evaluation of Tracking Mission Task Elements for the Assessment of High-Speed Handling Qualities

2020 ◽  
Vol 65 (3) ◽  
pp. 1-23
Author(s):  
David H. Klyde ◽  
Sean P. Pitoniak ◽  
P. Chase Schulze ◽  
Paul Ruckel ◽  
James Rigsby ◽  
...  
Keyword(s):  
High Speed ◽  
Effective Means ◽  
Evaluation Process ◽  
Performance Criteria ◽  
Handling Qualities ◽  
Forcing Function ◽  
Compound Helicopter ◽  
Command Signals ◽  
And Performance ◽  
The Military

Updates to the military rotorcraft handling qualities specification are currently being considered that address the high-speed flight regime envisioned for the Future Vertical Lift platform of the U. S. Army. A team that features industry and academia has developed and evaluated a set of mission task elements (MTEs) that are defined to address vertical takeoff and landing (VTOL) high-speed handling qualities. Following the mission-oriented approach upon which ADS-33E-PRF is based, the MTEs were designed to meet different levels of precision and aggressiveness. Tracking MTEs based on a sum-of-sines (SOS) command signal were defined for precision, aggressive, and precision, nonaggressive applications. The command signals were derived from fixed-wing analogs that have long been used to evaluate aircraft handling qualities. While the precision, aggressive SOS tracking tasks, the primary subject of this paper, are surrogates for air-to-air tracking and nap-of-the-earth tracking, the known forcing function allows for complete open- and closed-loop pilot—vehicle system identification. The MTE objectives, descriptions, and performance criteria were assessed and refined via several checkout piloted simulation sessions. Formal evaluations were then conducted by Army test pilots at four simulator facilities, each featuring a unique high-speed platform including a generic winged-compound helicopter, two tiltrotor configurations, and a compound helicopter with coaxial rotors. To aid in the MTE evaluation process, baseline VTOL configurations were varied to achieve different handling qualities levels. Quantitative measures based on task performance and qualitative measures based on pilot ratings, comments, and debrief questionnaires were used to assess MTE effectiveness. The piloted simulation results demonstrated that the SOS tracking MTEs provided an effective means to discern precision, aggressive handling qualities in high-speed flight.

scholarly journals Research and Analysis of Permanent Magnet Transmission System Controls on Diesel Railway Vehicles

Electronics ◽  
2021 ◽  
Vol 10 (2) ◽  
pp. 173
Author(s):  
Lili Kang ◽  
Dongjie Jiang ◽  
Chaoying Xia ◽  
Yongjiu Xu ◽  
Kaiyi Sun
Keyword(s):  
Permanent Magnet ◽  
Control Strategy ◽  
High Speed ◽  
Control Strategies ◽  
Transmission System ◽  
Torque Control ◽  
Railway Vehicle ◽  
Transmission Systems ◽  
Traction Motor ◽  
Railway Vehicles

As the energy crisis and environmental pollution continue to be a gradual threat, the energy saving of transmission systems has become the focus of railway vehicle research and design. Due to their high-power density and efficiency features, permanent magnet synchronous motors (PMSM) have been gradually applied in railway vehicles. To improve the efficiency of the transmission system of diesel railway vehicles, it is a good option to use PMSM as both a generator and traction motor to construct a full permanent magnet transmission system (FPMTS). Due to the application of the new FPMTS, some of the original control strategies for diesel railway vehicle transmission systems are no longer applicable. Therefore, it is necessary to adjust and improve the control strategies to meet the needs of FPMTS. We studied several key issues that affect the reliability and comfort of the vehicles. As such, this paper introduced the FPMTS control strategy, including the coordinated control strategy of the diesel and the traction motor, the two degrees of freedom (2DOF) decoupling current regulator, the maximum torque control of the standardized unit current, the wheel slip protection control, and the fault protection strategy. The experiment was carried out on the test platform and the test run of the diesel shunting locomotive equipped with the FPMTS. The results showed that the control strategy described in this paper met the operation characteristics of the FPMTS and that the control performance was superior. The study of FPMTS lays the foundation for the subsequent application of permanent magnet motors in high-powered diesel locomotives and high-speed diesel multi-units.

Integrated Control of Rotating Stall and Surge in High-Speed Multi-Stage Compression Systems

1997 ◽  
Author(s):  
K. M. Eveker ◽  
D. L. Gysling ◽  
C. N. Nett ◽  
O. P. Sharma
Keyword(s):  
Active Control ◽  
Control Strategy ◽  
High Speed ◽  
Control Strategies ◽  
Integrated Control ◽  
Axial Flow ◽  
Rotating Stall ◽  
Low Flow ◽  
Multi Stage ◽  
Simultaneous Control

Aeroengines operate in regimes for which both rotating stall and surge impose low flow operability limits. Thus, active control strategies designed to enhance operability of aeroengines must address both rotating stall and surge as well as their interaction. In this paper, a previously developed nonlinear control strategy that achieves simultaneous active control of rotating stall and surge is applied to a high-speed 3-stage axial flow compression system with operating parameters representative of modern aeroengines. The controller is experimentally validated for 2 compressor builds and its robustness to radial distortion assessed. For actuation, the control strategy utilizes an annulus-averaged bleed valve with bandwidth on the order of the rotor frequency. For sensing, measurements of the circumferential asymmetry and annulus-averaged unsteadiness of the flow through the compressor are used. Experimental validation of simultaneous control of rotating stall and surge in a high-speed environment with minimal sensing and actuation requirements is viewed as another important step towards applying active control to enhance operability of compression systems in modem aeroengines.

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