A Sensorless Drive Strategy for Open-End Winding PMSM With Common DC Voltage Based on Lower Switching Frequency

<p><span>This paper presents the minimization of the total harmonic distortion (THD) of the current signal for open-end winding induction motor by using dual two-level inverter. In order to obtain a good value of THD, the space vector PWM has been used for switching the dual two-level inverter to improve the output voltage quality, gets a low common mode voltage, reduce the execution time, and to save the memory capacity. The proposed scheme uses two different DC voltage source with two two level inverter in order of minimizing the number of components. As well as it is an important to utilize the energy which increases the application of dual inverter in microgrids. All simulation results are obtained using Matlab/Simulink. </span></p>

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Optimal Predictive Control Method of PWM Rectifiers Based on Artificial Intelligence

Mobile Information Systems ◽

10.1155/2021/3688228 ◽

2021 ◽

Vol 2021 ◽

pp. 1-9

Author(s):

Yue Liu ◽

Guojun Tan

Keyword(s):

Pid Control ◽

Pulse Width Modulation ◽

Control Method ◽

Estimation Method ◽

Weight Coefficient ◽

Switching Frequency ◽

Initial Weight ◽

Dc Voltage ◽

Grid Voltage ◽

Instantaneous Power

Direct power control (DPC) of pulse width modulation (PWM) is often used to control the instantaneous power of rectifiers. The instantaneous power contains both grid voltage and current information, and its value is not affected by coordinate transformation. It is constant in steady state and reflects the DC control characteristics. However, the switching frequency of traditional DPC is not fixed, the DC voltage has static error, and the system fluctuates greatly. In this work, we introduce the concept of stator flux of the AC motor into the PWM rectifier. Combined with the space vector PWM (SVPWM) technology, we use the virtual flux estimation method to obtain the instantaneous power value, which saves the grid voltage sensor, eliminates the static difference of DC voltage. Furthermore, considering that the neural proportion integral differential (PID) control depends heavily on the initial weight coefficient of the network, we use chaos particle swarm optimization (CPSO) algorithm, which combines the basic PSO algorithm and chaos theory to optimize the initial weight coefficient of neural PID control. In the experiment, the results prove that the performance of the controller can be effectively improved.

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Step-Up Series Resonant DC–DC Converter with Bidirectional-Switch-Based Boost Rectifier for Wide Input Voltage Range Photovoltaic Applications

Energies ◽

10.3390/en13143747 ◽

2020 ◽

Vol 13 (14) ◽

pp. 3747 ◽

Cited By ~ 1

Author(s):

Abualkasim Bakeer ◽

Andrii Chub ◽

Dmitri Vinnikov

Keyword(s):

Theoretical Analysis ◽

Duty Cycle ◽

Input Voltage ◽

Voltage Regulation ◽

Switching Frequency ◽

Voltage Gain ◽

Voltage Range ◽

Dc Voltage ◽

Wide Range ◽

Series Resonant

This paper proposes a high gain DC–DC converter based on the series resonant converter (SRC) for photovoltaic (PV) applications. This study considers low power applications, where the resonant inductance is usually relatively small to reduce the cost of the converter realization, which results in low-quality factor values. On the other hand, these SRCs can be controlled at a fixed switching frequency. The proposed topology utilizes a bidirectional switch (AC switch) to regulate the input voltage in a wide range. This study shows that the existing topology with a bidirectional switch has a limited input voltage regulation range. To avoid this issue, the resonant tank is rearranged in the proposed converter to the resonance capacitor before the bidirectional switch. By this rearrangement, the dependence of the DC voltage gain on the duty cycle is changed, so the proposed converter requires a smaller duty cycle than that of the existing counterpart at the same gain. Theoretical analysis shows that the input voltage regulation range is extended to the region of high DC voltage gain values at the maximum input current. Contrary to the existing counterpart, the proposed converter can be realized with a wide range of the resonant inductance values without compromising the input voltage regulation range. Nevertheless, the proposed converter maintains advantages of the SRC, such as zero voltage switching (ZVS) turn-on of the primary-side semiconductor switches. In addition, the output-side diodes are turned off at zero current. The proposed converter is analyzed and compared with the existing counterpart theoretically and experimentally. A 300 W experimental prototype is used to validate the theoretical analysis of the proposed converter. The peak efficiency of the converter is 96.5%.

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