Transformers and electrical motors

The aerospace industry is increasingly transitioning from hydraulic and pneumatic drives to power-electronic based drive systems for reduced weight and maintenance. Electromechanical thrust reverse actuation systems (EM-TRAS) are currently being considered as a replacement for mechanical based TRAS for future aircraft. An EM-TRAS consists of one or more power-electronic drives, electrical motors, and gear-trains that extend/retract mechanical members to produce a drag force that decelerates the aircraft upon landing. The use of a single (“central”) power electronic converter to simultaneously control a set of parallel induction machines is a potentially inexpensive and robust method for implementing EM-TRAS. However, because the electrical motors may experience different shaft torques—arising from differences in wind forces and a flexible nacelle—a method to implement rotor position synchronization in central-converter multi-motor (CCMM) architectures is needed. This paper introduces a novel method for achieving position synchronization within CCMM architecture by using closed-loop feedback of variable stator resistances in parallel induction machines. The feasibility of the method is demonstrated in several case studies using electromagnetic transient simulation on a set of parallel induction machines experiencing different load torque conditions, with the central converter implementing both voltage-based and current-based primary control strategies. The key result of the paper is that the CCMM architecture with proposed feedback control strategy is shown in these case studies to dynamically drive the position synchronization error to zero. The initial findings indicate that the CCMM architecture with induction motors may be a viable option for implementing EM-TRAS in future aircraft.

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DETERMINATION OF STATISTICAL CHARACTERISTICS OF STEEL MILL'S ELECTRICAL MOTORS BY THE REGRESSION ANALYSIS

10.12681/eadd/4420 ◽

1979 ◽

Author(s):

Ι. ΚΥΠΑΡΙΣΣΗΣ

Keyword(s):

Regression Analysis ◽

Statistical Characteristics ◽

Electrical Motors

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Decoupled Multi-Loop Robust Control for a Walk-Assistance Robot Employing a Two-Wheeled Inverted Pendulum

Machines ◽

10.3390/machines9100205 ◽

2021 ◽

Vol 9 (10) ◽

pp. 205

Author(s):

Fu-Cheng Wang ◽

Yu-Hong Chen ◽

Zih-Jia Wang ◽

Chi-Hao Liu ◽

Pei-Chun Lin ◽

...

Keyword(s):

Robust Control ◽

Transfer Function ◽

Inverted Pendulum ◽

Control Structure ◽

Position Tracking ◽

Loop Control ◽

Wheeled Inverted Pendulum ◽

Decoupled Control ◽

Rotational Motions ◽

Electrical Motors

This paper develops a decoupled multi-loop control for a two-wheeled inverted pendulum (TWIP) robot that can assist user’s with walking. The TWIP robot is equipped with two wheels driven by electrical motors. We derive the system’s transfer function and design a robust loop-shaping controller to balance the system. The simulation and experimental results show that the TWIP system can be balanced but might experience velocity drifts because its balancing point is affected by model variations and disturbances. Therefore, we propose a multi-loop control layout consisting of a velocity loop and a position loop for the TWIP robot. The velocity loop can adjust the balancing point in real-time and regulate the forward velocity, while the position loop can achieve position tracking. For walking assistance, we design a decoupled control structure that transfers the linear and rotational motions of the robot to the commands of two parallel motors. We implement the designed controllers for simulation and experiments and show that the TWIP system employing the proposed decoupled multi-loop control can provide satisfactory responses when assisting with walking.

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