PWM Method Research Articles

Integration of Home Automation and Security System Controller with FPGA Implementation

A home automation system is essential for promoting a safe and comfortable living environment and notable energy conservation for the user. However, the system’s favour had been obstructed by cost, power usage, inadequate security, complexity, and no emergency backup power. Current home automation systems with controllers were limited by their number of ports, fixed architecture, non-durable and non-parallel executions. Keeping this in view, integration of home comfort system, security system, and the automatic load transfer switch features are proposed using the base of Cyclone IV E: EP4CE115F29C7 FPGA Board (DE2-115). The top-level module is developed via Verilog Hardware Descriptive Language (HDL) with the bottom-up technique and used test bench for functional verification via ModelSim-Altera. The PWM method was applied to the lighting system to control the dimming of light through its digital signals via a maximum 500000 counter to improve energy efficiency for the proposed design. In this project, 200Hz pulses are successfully simulated to prevent visible flickering of lights in duty cycle generation. The light intensity of 40% and 100% are verified and successfully generated according to the inputs provided by the status of the LDR sensor and IR sensor. The proposed controller gives correct corresponding outputs to the 13 actuators based on the detected input stimuli. The proposed design utilized a total of 162 (<1%) logic elements, 32 registers, and total pins of 74 (14%). The proposed design successfully integrated the three-sub module and provided control on comfort and security system operations to prevent service failure during power blackout conditions at the top-level and utilized a low ratio of the FPGA.

Discontinuous PWM Technique With Reduced Low-Order Harmonic Distortion for High-Power Applications

The modulation techniques used in high power applications have to generate high quality waveforms with reduced switching losses. As an attractive alternative, Discontinuous PWM (DPWM) techniques present lower device switching frequencies than conventional continuous PWM methods lowering the converter switching loss. Considering the same cooling system, this allows to increase the carrier frequency of DPWM methods displacing the main switching harmonics to higher frequencies. As a main drawback, when low carrier to fundamental ratios are used, DPWM methods present some undesired low-order harmonics that are required to be filtered. This paper presents a low-order harmonic minimization method for synchronous DPWM methods by modifying the conventional modulating reference to limit low order harmonics amplitude, while keeping the same effective switching frequency and thus limited switching losses.

Performance evaluation of hybrid multilevel inverter with a high-frequency switching technique

This proposed work deals with the implementation of a single-phase topology with using hybrid for multilevel inverters. It is observed that the proposed structure improves the performance of the hybrid multilevel inverter with high-frequency switches for positive levels and reverse voltage with negative levels. This paper studies a novel construction for an asymmetrical hybrid single-phase multilevel inverter. This paper also studies the operation of multi level inverter under depreciating sources condition due to fluctuation in input. The PWM method, i.e. APOD and CO, has been incorporated into the simulation of single-phase 7-level, 9-level, and the 11-level hybrid inverter. These two methods are compared to one another and to standard methods in terms of THD for different values of the modulation index, and they are found to be superior. Overall loss of 50% of the THD is almost equal to rated output voltage, it is observed in cascaded multilevel inverters. The working and performance of the proposed model are simulated in MATLAB Simulink software and the results are discussed in detail.

Comparison of Pulse Width Modulation Techniques for Diode-Clamped and Cascaded Multilevel Inverters

Multilevel inverter technology has become the most significant method of energy conversion from DC to AC for uninterrupted power supply. The quality of the power supply depends on the appearance of harmonics, which is considered a problem that needs to be overcome. This paper demonstrates the use of a new modulation technique to reduce the harmonics in both diode-clamped and cascaded multilevel inverters, examining its Total Harmonic Distortion (THD) compared to other PWM methods. Simulations were carried out in MATLAB/Simulink for five-level diode-clamped and cascaded multilevel inverters. The simulation results of both multilevel inverters using the sinusoidal PWM, modified reference PWM, modified carrier PWM, and modified reference and modified carrier PWM methods showed that the latter had the best THD performance for both inverter types, especially for the cascaded multilevel inverter.

Dual randomized discontinuous pulse width modulation for three-phase inverter

ABSTRACT The discontinuous PWM technique, with its advantage over the continuous PWM technique in reducing switching losses in power converters, is gaining popularity. However, its deterministic nature results in discrete harmonics with significant amplitudes, which leads to electromagnetic interference (EMI) emissions. The randomised PWM technique is gaining more interest because of its effectiveness in spreading the harmonic spectrum and thus reducing EMI problems in power converters. This paper presents a carrier-based dual randomised discontinuous PWM (DRDPWM) method for a three-phase voltage inverter. The DRDPWM method combines the random carrier frequency (RCF-DPWM) and random pulse position (RPP-DPWM) schemes. In addition to reducing switching losses, DRDPWM can achieve a broad spread of the voltage spectrum with significantly smaller amplitudes. Furthermore, it produces less inverter output current distortion when compared to traditional DPWM and simple random (RCF-DPWM and RPP-DPWM) schemes. Simulations and experimental results confirm the effectiveness of the suggested method for spreading the voltage spectrum compared to simple random schemes. Additionally, an evaluation of the performance of all randomised discontinuous schemes is conducted based on a number of assessment metrics, including the switching loss factor (SLF), the power spectral density (PSD), the harmonic spread factor (HSF), and the quality factor (QF).

A Power Quality Assessment of Electric Submersible Pumps Fed by Variable Frequency Drives under Normal and Failure Modes

This paper proposed a simplified modeling approach for a power quality (PQ) assessment of Electric Submersible Pumps (ESP) systems supplied by the two-level, the neutral-point-clamped three-level, and the cascaded H-bridge (CHB) multilevel inverter VFD topologies. The VFD switching function models and their analytical expressions are proposed to understand how they can create high-frequency components that might excite the resonance mode in a transmission cable or a rotating shaft system. Voltage, current, and motor airgap torque harmonics induced by each VFD topology in a balanced operation mode are derived and correlated to the PWM carrier and motor operating frequencies. The motor airgap harmonics are calculated based on Concordia’s transformation of voltages and currents in αβ-plan. These harmonic components are represented in the form of Campbell diagrams. An analysis of harmonics under unbalanced conditions was also conducted in a CHB VFD topology-powered ESP system with failed and bypassed cells. The investigated modulation technique is a neutral-shift PWM method that enables the system to operate balanced line-line voltages even if the line-neutral voltages are unbalanced. The effects of modifying the electrical spectrum using the neutral-shift PWM method on electrical and mechanical spectra are analyzed. The results of the Matlab/Simulink-based simulation show that the proposed full ESP system model is highly accurate in both normal and failure modes. The results are consistent with theoretical predictions and are graphically shown in the time and frequency domains for easy analysis. Hybrid experimental–numerical results on a reduced-scale laboratory setup are also discussed to confirm the correctness of the suggested developments.

Theoretical Study of Rampwise DPWM Technique to Reduce Motor Acoustic Noise

Motor acoustic noise generated near living environments such as elevators and electric vehicles may cause discomfort. In order to reduce the acoustic noise, the switching frequency is set to the high side of the audible frequency range. In this case, however, the switching loss is increased. The conventional discontinuous PWM (DPWM) method is widely used since it can reduce the switching loss drastically. However, it produces larger acoustic noise than the conventional sinusoidal PWM method. The authors have previously proposed Rampwise DPWM techniqueh which can reduce both acoustic noise and switching loss. In this paper, the line-line voltage with the proposed Rampwise DPWM technique is expanded into a real-valued Fourier series, and the frequency characteristics are analyzed. It is theoretically confirmed that the rampwise part in the Rampwise DPWM technique can achieve reduction of motor acoustic noise. Furthermore, the reduction effect of motor acoustic noise with the Rampwise DPWM technique is theoretically and experimentally verified.

A PWM Method for Reducing dv/dt and Switching Losses in Two-Stage Power Converters

Today's semiconductor devices are accompanied by high switching frequencies (> kilo-hertz) and small transition times (< micro-seconds). Such fast transition times are accompanied by undesirable effects such as voltage overshoots at the load terminals, ground leakage currents, wide-band electromagnetic noise, etc. With the advent of wide band-gap devices, several applications are moving towards higher switching frequency operation with at-least an order of magnitude reduction in transition times. While these characteristics are considered necessary to break the next-generation barriers in power density, efficiency and applicability, the undesirable effects due to faster transitions are expected to present obstacles. This work proposes a PWM approach to modify the shape of the switching voltages to overcome the disadvantages of the fast transition times without any increase in switching losses. In fact, several of the switching transitions feature ZVS operation, resulting in reduced switching losses. The paper discusses the analytical details of the approach using a simple DC-DC boost-buck converter and extends it to a DC to three-phase AC converter using the principles of space vector modulation. The paper presents detailed simulation and comparative results in terms of voltage over-shoots over long cables, loss calculations and electromagnetic noise. Results from a laboratory-scale working prototype confirm the benefits of the proposed approach in terms of EMI and loss reduction.

A Novel Electromagnetic Noise and Image Stripe Noise Suppression Method Between SMA-OIS Actuator and CMOS Image Sensor

In order to solve the electromagnetic compatibility (EMC) problem between shape memory alloy (SMA) optical image stabilization (OIS) actuator and CMOS image sensor (CIS), a novel electromagnetic noise and image stripe noise (ISN) suppression method is proposed in this paper. The electromagnetic interference mechanism of SMA-OIS actuator is analyzed by electromagnetic field simulation and magnetic dipole mathematical model. The CIS noise mechanism based on the readout circuit model and image signal processing (ISP) pipeline is analyzed and the ISN evaluation method of CIS is proposed. The drive frequency and ISN model is established by frequency sweep experiment through the joint experimental platform of SMA-OIS actuator and CIS. Furthermore, the random frequency modulation PWM method based on the spread spectrum principle is proposed to suppress the electromagnetic noise and ISN. The experimental results show that the state-of-the-art noise suppression method proposed in this paper can not only eliminate ISN, but also have good technical adaptability in practical applications.

태양광 시스템에서 불연속 전압 변조 방법 적용에 따른 단상 5-레벨 T-type NPC 인버터의 전력 반도체 소자의 전력손실 및 열 부하 분석

The pulse width modulation method has a significant effect on the power losses and thermal loadings of power devices of a single-phase five-level T-type NPC photovoltaic (PV) inverter. In this paper, the comparative analysis of the power losses and thermal loadings of a single-phase five-level T-type NPC inverter is performed under the different pulse width modulation methods. When the unipolar pulse width modulation method is applied, the power losses and thermal loadings of the power devices are evaluated, and the reliable critical power devices with the highest thermal loadings are identified. Subsequently, the power losses and thermal loadings of the power devices are analyzed by applying the discontinuous pulse width modulation methods such as one-pole clamping pulse width modulation method and equally distributed discontinuous pulse width modulation method. Their effects on the reliability of the inverter are evaluated. Additionally, the operation of a T-type NPC inverter with three PWM methods is verified through the experiment.

Hybrid-Clamping SVPWM Scheme for a Four-Level Open-End Winding Induction Motor Drive

An open-end winding arrangement is fed with two typical 2-level voltage source inverters (VSIs) on either side to accomplish multilevel inversion. Two voltage source modules (VSIs) DC-link voltages are kept at a 2:1 ratio to realize the open-end winding induction motor (OEW-IM) power circuit’s four-level configuration. However, the higher DC-link voltage capacitor overcharges its lower DC-link voltage counterpart in the 4-level power circuit configuration. This article proposes a new hybrid-clamping space vector PWM (SVPWM) approach to prevent overcharging. Based on the sample moment, the suggested SVPWM technique clamps one inverter and switches to another inverter. Additionally, it clamps one of the inverter’s switching phases. The proposed PWM method has been found to reduce switching power loss in contrast to earlier SVPWM methods. The proposed SVPWM scheme for the 4-level OEW-IM drive is tested and verified using an experimental laboratory setup.

An Improved Modulation Scheme With Better Performance for Open-Winding Permanent Magnet Synchronous Motors Drives

In order to improve the performance of voltage synthesis of the open-winding permanent magnet synchronous motors (OW-PMSMs) with isolated DC bus when the voltages of two power supplies are not equal, an innovative voltage modulation method is proposed. The novel method is based on the conventional alternate sub-hexagonal center PWM method, but the low-voltage powered inverter is kept at low-potential clamped state throughout a period instead of having the two inverters clamped alternately. In this way, the high-voltage powered inverter expands the range of voltage synthesis, making up for the deviation between the synthesized voltage and the voltage reference when the high-voltage powered inverter is clamped and the low-voltage powered inverter modulates individually. Therefore, compared with the traditional method, a larger total voltage synthesis range is covered so that the capability of voltage synthesis is enhanced, thereby improving the quality of the corresponding torque and the output current. The simulation and experimental validations are presented to certify the effectiveness of the proposed method under different conditions, and the results prove that the new method indeed improves the current performance and reduces torque ripples.

Harmonic Mitigation Using Meta-Heuristic Optimization for Shunt Adaptive Power Filters: A Review

Shunt Adaptive Power Filter (SAPF) is widely used in the performance of power quality improvement activities in the power supply industry for processing industries or civil power sources in the world today based on its simplicity, transparency, high reliability, efficiency, and reliability, and their powerful compensating current-providing nature. The PI controller integrated into the SAPF operation mechanism works with extra high efficiency in selecting the current to compensate for the lost current generated in the power supply due to harmonics generated by the Kp, Ki parameter values. The system operates by the PWM method for bridge rectifier circuits that perform the function of selecting the appropriate compensating current, providing correct compensation for the amount of current loss in the power supply. Adjusting the Kp, Ki parameter to reach the optimal value by different methods is a promising and popular research direction at present. The Kp, Ki parameter serves the right purpose for the PI controller to generate enough PWM pulses to excite the bridge rectifiers to generate just the right amount of compensating current and enough current to be compensated on the power supply. The commonly used Kp, Ki parameter adjustment methods include the Ziegler Nichols closed-loop vibration method, the P-Q theoretical method, and several other methods. This study conducts a comprehensive review of the literature on modern strategies for adjusting the Kp, Ki parameters in the PI controller in the SAPF suite by using the meta-heuristic optimization method. This study performs classification according to the operation mode of meta-heuristic optimization methods to adjust the Kp, Ki parameter to control the PI to select the correct PWM frequency to activate bridge rectifiers to select the most optimal compensation current to compensate for the loss of current on the power supply to meet the goal of improving power quality in accordance with IEEE 519-2022 standard, leading to the total harmonic distortion (THD) value is below 5%. The study presents in detail some meta-heuristic optimization algorithms, including applications, mathematical equations, and implementation of flow charts for SAPF and provides some open problems for future research. The main objective of this study is to provide an overview of applying meta-heuristic optimization algorithms to the Kp, Ki parameter tuning of PI controllers.

Optimization of thermoelectric temperature control systems

Objective. The aim of the study is to study the methods of temperature control using the Peltier element in a given temperature range.Method. A heating method is applied using a Peltier element in a temperature control device of a small plate by regulating the current and using a cooling fan to reduce inertia.Result. A technique for controlling the Peltier element to maintain the required temperature is obtained, which is carried out using the PWM method generated by the ATmega2560 processor. The H-bridge on the L6203 integrated circuit switches the current direction and can control the current up to 5A on the Peltier element using a PWM signal.Conclusion. The resulting control algorithm provides an increase in the heating current on the Peltier until the temperature rises to a predetermined high temperature value, and then by changing the direction of the current, a cooling current is created on the Peltier element until the temperature of the copper plate drops to a predetermined low temperature. With repeated repetition of this sequence, the regularity of temperature changes is monitored to study the process of heating and cooling the plate using the Peltier element.

Speed Control of Induction Motor by Using Voice Recognition Using Bluetooth

The project's goal is to develop a voice recognition and Bluetooth communication-based system for managing an induction motor's speed. The system is made up of two primary components: the speech recognition module, which is in charge of understanding user voice instructions, and the motor control module, which regulates to response to user voice commands. A speech recognition algorithm processes the user's vocal commands after being captured by the voice recognition module's microphone. control module receives the commands from the algorithm via Bluetooth communication. PWM method is used by the module to adjust the speed of induction after receiving commands. Without the use of physical buttons or switches, voice recognition technology offers customers a simple and practical way to adjust the motor's speed. The study shows that voice recognition technology and Bluetooth connectivity may be used to regulate the speed of induction motors, providing a practical and user-friendly solution for a variety of applications. Key Word: Induction motor, voice recognition, pulse-width modulation.

Development of Controllino Program to Integrate the Sensor Inputs for Motors Control

The system fishcake machine available in the market cannot be controlled by its motor speed based on the desired speed. In addition, this machine uses PLC which causes the production cost of the machine to increase, cannot use components that have a small voltage such as 5V and indirectly makes the PLC a difficult component to integrate all types of components in one PLC only. So, in this paper, we will develop a program using MAXI Automation Controllino for motor speed control that can be changed according to the desired speed with PWM method. In addition, to analyse and validate the integration sensors and motors to control the entire system. Finally, in this study we use Controllino type Maxi Automation to replace the existing PLC in the market and this Controllino will relate to a sensor that is an ultrasonic sensor, infrared range sensor and a DC motor. To control this system, we use a software method that is Arduino IDE to write all the coding. This coding will be written based on all the programs or processes involved in the fishcake machine performed.

Design and Analysis of Solid State DC-AC Transformer

Multimodal single/dual stage conversion (BSDC) based on a new solid-state DC-AC transformer (SDAT) is proposed. The suggested conversion can perform variable or constant DC voltage operation. A variable DC voltage is controlled dynamically in response to changes in DC input side voltage, allowing the DC-DC conversion stage to always operate at its best. New DC-AC power conversion of 2 port two-way choppers (TBDC) and two-way rectifier/inverter conversion (BRIC) was planned for the implementation of the proposed SDAT. SDAT, consisting of a bi-directional step-down-step-up converter and a bi-directional step-up-step-down converter, has been used as a prototype model to check the suggestion system. Functional concepts of this BSDC converter with TBDC are designed and simulated on the MATLAB/simulink environment network. PWM and control methods have been applied for SDAT to accomplish a wide variety of voltage and power loss reduction in the proposed device. Test bench model hardware is designed and tested to validate the effectiveness and benefits of the proposed approach.

An Enhanced Space Vector PWM Strategies for Three Phase Asymmetric Multilevel Inverter

This work presents the two space vector pulse width modulation (SVPWM-I and SVPWM-II) strategies for eleven-level (11L) asymmetric cascaded H-bridge (CHB) multilevel inverter (MLI). Depending on the isolated structure and nonappearance of capacitor voltage balancing issues, the CHB MLI structure is favoured. These days, the SVPWM control method is accomplished superior consideration among the diverse PWM methods. In common, the SVPWM strategy is realized based on deteriorating higher-level hexagons into a lower level hexagon (2-level). Compared to the classical SVPWM strategy, the proposed SVPWM-I strategy decreases the memory and mathematical burden necessity included within the demonstration of eleven-level SVPWM devoid of losing the inverter output voltage (AC) contour by diminution the number of two-level hexagons. Also, the SVPWM-II strategy is presented, which incredibly diminishes the mathematical endeavours. The presented two SVPWM methods performed on an eleven-level asymmetric CHB multilevel inverter (MLI) by utilizing SIMULINK/MATLAB program tool and are compared with conventional sinusoidal PWM and Third harmonic injection (THI) PWM methods to confirm the proposed SVPWM methods. The proposed SVPWM methods give higher AC RMS voltage and lower harmonic distortion when compared to SPWM and THIPWM methods. To validate the presented two SVPWM control schemes, hardware results are taken on asymmetric eleven-level CHB MLI.

A Wide Bandwidth GaN Switching Power Amplifier of Active Magnetic Bearing for a Flywheel Energy Storage System

A switching power amplifier (SPA) provides the driving current for an active magnetic bearing (AMB) to achieve magnetic suspension (MS) control. The performances of the current bandwidth and current ripple should be significantly considered in the SPA of the AMB. The SPA can obtain a wide bandwidth by increasing the dc-link voltage. However, a high dc-link voltage will cause a high current ripple. To achieve a wide bandwidth and low current ripple, a new GaN-device-based SPA for the AMB of a flywheel energy storage system (FESS) is proposed in this article. The GaN SPA can operate at a high switching frequency and high dc-link voltage. Thus, the GaN SPA can improve the performance of the current bandwidth and current ripple compared to the conventional SPA. According to the characteristics of the GaN SPA, a low-loss PWM method and an optimal dead time strategy is proposed to increase the efficiency of the SPA. Furthermore, a high-response control approach of dead-beat model predictive control is proposed to further improve the current bandwidth. The proposed GaN SPA is applied in a 500-kW MS FESS prototype. The effectiveness of the SPA is verified experimentally.

A compensation pixel circuit with high bits using PWM method for AMLED

An AMLED compensation pixel circuit, cracking the boundary that the internal compensation in addition with pulse width modulation driving approach is hard to get high-bit performance, is proposed in this work. A case study of a panel with the fresh rate of 120 Hz and resolution of 20 × 20, through adding the extinguish TFT for converting the PWM equal distribution fields to unequal segments, the bit number is greatly increased from three bits to eight bits. Moreover, the current error ratio of novel 6T1C is less than 4.6%, proving that novel 6T1C circuit is proper to increase the bit number and optimize the reliability of display panel.