Pulse Width Modulated (PWM) Inverters for Efficiency Optimal Control of AC Drives – switching Angles and Efficiency/Loss Profiles *

Precise torque control without pulsations is one of the major quality issues in pulse-width modulated voltage-source inverter (PWM-VSI) drives. Theoretically, it could be postulated that at frequencies of some kHz, the machine’s inertia absorbs switching frequency torque harmonics, and the resulting torque becomes smooth; though, in reality, parasitic effects in voltage source inverters may cause additional torque harmonics of low order. In particular, first, second and sixth torque harmonics are observed. Such torque harmonics are especially dangerous for normal drive operation, since they may be amplified by drive train resonances at corresponding rotational velocities. New parasitic effects in PWM-VSI control, leading to torque harmonic of low order, are described in the paper, and recommendations for their compensation are given.

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On the Equivalence of Discrete Systems in Time-Optimal Control

Journal of Basic Engineering ◽

10.1115/1.3656562 ◽

1963 ◽

Vol 85 (2) ◽

pp. 204-210 ◽

Cited By ~ 4

Author(s):

E. Polak

Keyword(s):

Optimal Control ◽

Control Strategy ◽

Pulse Width ◽

Discrete System ◽

Discrete Systems ◽

Order Linear Differential Equation ◽

Optimal Control Strategy ◽

Pulse Width Modulated ◽

Time Optimal ◽

Linear Differential

It is shown in this paper that under a transformation which maps the state space of a system onto a sequence space in a one-to-one manner, time-optimal discrete regulator systems with different dynamics and modulators can be brought to equivalence and that this fact may be used to construct an optimal control strategy for one system from the known optimal control strategy of another one. In particular, the optimal control strategy for a pulse-width-modulated discrete system with a plant described by an nth order linear differential equation is derived in this manner.

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Pulse Width Modulated FPGA Based Digital Controller For Microstepping Stepper Motor Drive For Solar-Array Drive In Satellites

i-manager’s Journal on Instrumentation and Control Engineering ◽

10.26634/jic.1.2.2232 ◽

2013 ◽

Vol 1 (2) ◽

pp. 14-18 ◽

Cited By ~ 1

Author(s):

Sachin Angadi ◽

◽

Satyanarayana Kumari B ◽

H .V. Saikumar ◽

◽

...

Keyword(s):

Pulse Width ◽

Digital Controller ◽

Stepper Motor ◽

Solar Array ◽

Motor Drive ◽

Pulse Width Modulated

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Pulse-Width Modulated Amplifier for DC Servo System and Its Matlab Simulation

The Open Electrical & Electronic Engineering Journal ◽

10.2174/1874129001509010625 ◽

2015 ◽

Vol 9 (1) ◽

pp. 625-631

Author(s):

Ma Xiaocheng ◽

Zhang Haotian ◽

Cheng Yiqing ◽

Zhu Lina ◽

Wu Dan

Keyword(s):

Mathematical Model ◽

Transfer Function ◽

Input Signal ◽

Pulse Width ◽

Rotation Speed ◽

Servo Motor ◽

Matlab Simulation ◽

Pulse Width Modulated ◽

Signal Changes ◽

The Relationship

This paper introduces a mathematical model for Pulse-Width Modulated Amplifier for DC Servo Motor. The relationship between pulse-width modulated (PWM) signal and reference rotation speed is specified, and a general model of motor represented by transfer function is also put forward. When the input signal changes, the rotation speed of the servo motor will change accordingly. By changing zeros and poles, transient performance of this system is discussed in detail, and optimal ranges of the parameters is recommended at the end of discussion.

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