PWM Signal Research Articles

An efficient soft-switched vienna rectifier topology for EV battery chargers

The requirement of high power rated, efficient and high power density grid connected converters has increased due to their extended use in multiple applications such as battery chargers. The proliferation of electric vehicles (EVs) in the transportation market is essentially associated with the performance and reliability of battery chargers. An efficient, compact and fast battery charger is indispensable in order to provide a way to charge an EV in a short time. In view of this fact, this article proposes a soft-switching three-level T-type vienna rectifier, which can be used as a front-end power stage converter in an on-board EV battery charger. The proposed topology achieves high efficiency and high power density by employing soft-switching strategy, which is achieved by incorporating a simple auxiliary network in the proposed circuit. The reduced component stresses and simple control strategy make it an appealing candidate for EV industries to develop this front-end PFC rectifier as a fast battery charger. The high switching operation with reduced power losses, regulated DC at the output, low-harmonic grid current and power factor correction operation are achieved with the proposed topology. The construction, operating principle and simulation analysis of the proposed converter are discussed in detail. In order to show the stand-point of the proposed scheme, a fair comparison of the proposed soft-switched converter with an existing soft-switched 3-level neutral-point diode-clamped converter is carried out in terms of the number of components and complexity in the PWM signals generation. Additionally, an efficiency comparison of the suggested converter is carried out with some existing well-known rectifier topologies at different power loads. The practical implementation of the proposed power converter scheme is checked by building a laboratory-prototype to perform an experimental analysis.

10.2: A Novel GOA Providing Both Emission‐controlled PWM Signal and Switch‐controlled Scan Signal for AMOLED Displays

For the purpose of simplifying the gate driver on array for AMOLED panels using p‐LTPS or LTPO TFTs, a novel shift register module circuit was developed. Integrating the module with the common‐used EM GOA, a simplified GOA integrated both functions for generating emission‐controlled n‐type EM signal and switch‐controlled scan signal was developed. The feasibility of the proposed circuit was demonstrated through simulations results.

Research on the module of color image sonar system based on imx6ull

Underwater sonar imaging system has a wide range of application prospects, and both military and civil are increasingly valued. This paper introduces the module design of a color image sonar system based on IMX6ULL and completes the imaging of the sonar system through experiments. The main frequency and sampling frequency of the system are improved and applied to the TKIS-I color image sonar digital system. High-performance A / D is used for data acquisition and storage, and RS485 is used for long-distance transmission to the host computer to realize display and imaging. It is mainly composed of a core board, PWM signal module, communication module, sampling module, and motor drive module. The processing speed and imaging effect of the improved system are significantly improved.

Modified hysteresis current control of multilevel converter for grid connected battery storage system

Due to active power demand in the distributed power system, the large voltage deviation appears in the grid network. The battery energy storage system is optimal solution to support the active power when it is needed, which improves the voltage stability. To maintain the accuracy in the active power injection, the modified hysteresis current control of multilevel converter for grid connected battery storage system is proposed in this paper. It supplies accurate active power by estimating the exact reference current from the grid voltage at every sampling period. This novel control mechanism ensures that there will not be any mismatch in the active power requirement and supply; thereby it enhances the quality of grid under nay situation. The detailed control block diagram is addressed to generate the required PWM signals. And also, the detailed operating waveforms are discussed in this paper. The equivalent circuit of power transfer to grid is also reported in this paper. Mathematically it gives that the proposed approach can inject the actual active power needed by the system. To validate the proposed modified hysteresis current control scheme of multi-level converter, the entire simulation study has been developed and carried out in PSCAD/EMDTC software. The measured results observed and presented in this paper and also it confirms that the proposed has practical feasibilities to implement in the real system.

Penerapan Sensor Ultrasonic SRF05 Berbasis Mikrocontroller ATMega 8535 Untuk Sistem Pengereman Otomatis

Transportation technology using electric energy is growing. Electric cars are increasingly being used to reduce fuel oil usage. In addition to the increasingly sophisticated performance of electric cars, the vehicle safety system must also be improved. The existence of Artificial Intelligence is one of the developments in technological sophistication in a world that is increasingly unstoppable and unavoidable. One of the most popular luxury cars in Indonesia, one of which is the Tesla, which is a sophisticated car with the support of an artificial intelligence system, making Tesla an electric car with an automatic control vehicle feature that can run without using a human driver and can provide safety protection for the driver by using automatic braking system in case of an unexpected accident. This journal proposes a future concept design for the forerunner of automatic braking for electric cars using the ATMEGA 8535 microcontroller as the main automatic control and ultrasonic distance sensor. The PWM signal from the microcontroller is used to adjust the speed of the DC motor as the main driving force of the vehicle. The display of the distance between the vehicle and the obstacle can be seen on the LCD and the buzzer is used as an indicator of the safe distance of the car. The experiment was carried out using an RC car with the area to be protected> 500cm (5m), if the SRF05 ultrasonic sensor detects an obstacle at that distance, the SRF05 ultrasonic sensor will send a signal to the microcontroller and turn on an alarm in the form of a buzzer so that the SRF05 ultrasonic sensor will stop signal propagation.

직렬 통신 기능을 이용한 대용량 계통연계형 인버터의 순환전류 저감방법

This paper proposes a circulating current suppression method of grid-connected inverters in parallel inverters using serial communication. The grid-connected inverter for large scale photovoltaic generation system consists of multiple modules in parallel based in unit inverter module. The existing method to synchronize PWM signals between inverter modules was implemented by CAN communication with high interrupt priority. However, the high priority of CAN communication can cause deterioration in current control performance due to limited resource of controller. This paper introduces an improved synchronization method of PWM signals with low interrupt priority using time stamp function. The effectiveness of the proposed method is verified by experimental results with 250kW inverter system.

Internet-of-Things for Smart Street Lighting System using ESP8266 on Mesh Network

<p class="0abstract">IoT concept gained tremendous momentum in this century's technological advancements because it has efficiently connected various devices wirelessly. The ESP8266 Wi-Fi serial transceiver module is one of the most used devices for IoT applications. This paper designs the IoT-based smart street lighting system using ESP8266 configured as a Mesh network. The ESP8266 was instructed (programmed) to control the light level by producing a PWM signal, then it sends a dimmer value and reads the sensor's data. We can access our system wirelessly via a web server. The overall system was successful as a smart street lighting system in a wireless Mesh environment. This research result is also compared to the existing similar project in terms of the system complexity aspect.</p>

A NEW CONTROLLER FOR PHOTOVOLTAIC PANEL FED UNIFIED POWER QUALITY CONDITIONER TO POWER QUALITY IMPROVEMENT

In this study, a new controller based on the synchronous reference frame (SRF) in a photovoltraic (PV) panel supported three-phase unified power quality conditioner (PV-UPQC ) is proposed to solve power quality problems in power systems. The serial and parallel active power filters fed with energy by PV panels are used together in the PV-UPQC system. In the proposed controller, measurement values are taken from four different points of the power system. The obtained values and DC voltage generated by PV panels are used to calculate the reference current and voltage values. PWM signals of switches used in active filters are produced using moving average filter and space vector-PWM. The algorithm used in both filters consists of two parts. The first is the mppt algorithm, in which the maximum voltage is obtained from the PV panels, and the second is the SRF-based proposed algorithm, where the reference current or voltage is obtained. Simulation and experimental studies of the proposed controller are applied. When the results obtained are examined, the proposed controller for three-phase PV-UPQC gives better results than the traditional SRF based controller in attenuation of harmonics in current and voltage.

IoT high-frequency electronic transformer with dimmable output voltage using PWM signals

This work presents the design, simulation, and implementation of a low-power electronic transformer, which output effective voltage can be controlled wirelessly through WIFI, via a user interface on a mobile phone. The methodology used in this project consists of 4 stages, a rectifier, an inverter, the inverter’s control system, and a ferrite reducer. The inverter has a full-bridge design and was implemented using MOSFET. The control system can vary the frequency and duty cycle of the output signals, by phase shifting the control signals, thus achieving the functionality of reducing the effective output voltage. Circuit design simulations were performed using PsPice Orcad. The implementation and the mathematical model of the built electronic transformer are carried out. The designed transformer operates with a maximum input voltage of 120 Vrms at 60 Hz at frequencies between 20 kHz and 30 kHz, which are controlled through the user interface; can reduce a 120 Vrms 60 Hz input signal to an effective voltage between 10 Vrms and 20 Vrms at a maximum power of 50 W. This project presents the feasibility of developing electronic transformers with variable output voltage, remotely controlled using IoT technology.

Speed Control of D.C Motor using GSM Technique

Electric drive systems employed in several industrial applications need higher performance, responsibleness, and skill to vary the speed. One among the enticing options of the dc motor over all alternative styles of motor is that the relative ease with that speed management may be achieved. During this paper, speed management of dc motor mistreatment GSM technology has been investigated. It's a closed-loop real time system, wherever the feedback circuit is coupled to the motor shaft to produce the feedback speed signal. A mobile phone is hooked up to the feedback circuit that is a trigger. The PWM signal are send to motor driver to vary the voltage provide to motor. GSM (SMS) controlled dc motor is automatic control system which capable of receiving a set of command instructions in the form of short message service and performs the necessary actions like start stop and speed control. We will be using a dedicated modem/mobile at the receiver module i.e., with the robot itself and send the commands using SMS service as per the required actions. The mobile unit which is dedicated at the motor driver is interfaced with an intellectual device called micro controller so that it takes the responsibility of reading the received commands in the form of SMS from the mobile unit and perform the corresponding predefined tasks such as motor start, stop, motor direction and speed control at different levels etc.

Bit Streaming Processing Algorithms for Intelligent Hardware Converters

The need to transfer the primary data conversions close to the sensors, to the endpoints of monitoring systems, as well as in IoT terminal devices makes the development of new approaches to computing and the design of appropriate algorithms relevant. The article shows stream processing algorithms that provide functional transformations of signals presented in bit stream form (single pulse streams, PWM signal streams) and binary codes at the same time. In such algorithms, the computational process is based on discretization, pulse frequency sweep and pulse-width sweep of codes as well as organization of parallel-serial processing. The suggested principles of algorithm organization are based on the fact that the computation is considered not as an event associated with calculation but as a continuous process of a result formation. The transition to algorithmic representations proposed by the authors makes it possible to obtain universal behavioral descriptions, independently of the specific hardware on which their implementation is performed.

An Improved Finite-Control-Set Model Predictive Flux Control for Asymmetrical Six-Phase PMSMs With a Novel Duty-Cycle Regulation Strategy

This work presents an improved finite-control-set model predictive flux control (FCS-MPFC) for asymmetrical six-phase permanent magnet synchronous machine (ASPMSM) with a novel duty-cycle regulation strategy. Firstly, virtual vector concept is adopted to suppress harmonic currents without additional cost function and the corresponding weighting factor. Then, 12 virtual vectors with higher voltage utilization are developed. Meanwhile, for the sake of strengthening steady-state performance, a novel duty-cycle regulation strategy incorporating the well-known Lagrange multiplier method is proposed. In this strategy, the reconfigurable set of voltage vectors (SVV), which consists of an active and a null virtual vector, can be determined without second modification, hence highly mitigating additional computation burden. Furthermore, in order to realize the purpose of unified switching frequency, the SVVs are implemented in terms of regular rather than irregular PWM signal pattern. Finally, experimental results prove the effectiveness of the proposed method.

Optimal SoC Balancing Control for Lithium-Ion Battery Cells Connected in Series

The optimal state of charge (SoC) balancing control for series-connected lithium-ion battery cells is presented in this paper. A modified SoC balancing circuit for two adjacent cells, based on the principle of a bidirectional Cuk converter, is proposed. The optimal SoC balancing problem is established to minimize the SoC differences of cells and the energy loss subject to constraints of the normal SoC operating range, the balancing current, and current of cells. This optimization problem is solved using the sequential quadratic programming algorithm to determine the optimal duties of PWM signals applied to the SoC balancing circuits. An algorithm for the selection of the initial points for the optimal problem-solving process is proposed. It is applied in cases where the cost function has no decreasing part. Experimental tests are conducted for seven series-connected Samsung cells. The optimal SoC balancing control and SoC estimation algorithms are coded in MATLAB and embedded in LabVIEW to control the SoC balancing in real time. The test results show that the differences between the SoCs of cells converges to the desired range using the proposed optimal SoC balancing control strategy.

Design of an Adaptive Boost Energy-Saving Fuzzy Control System Driven by the Finite State Machine

Aiming at the challenging problem of the traditional warp knitting machine electronic jacquard control system with complex structure of multiple circuit boards layered cascade, such as large physical space occupation, high power consumption, and independent high-voltage power supply voltage, we proposed an embedded circuit and control strategy design for the piezoelectric jacquard needle (PJN) with adaptive boost and energy recovery functions. Firstly, the electromechanical dynamics model of PJN was established. Secondly, the fuzzy PI double closed-loop control algorithm driven by a finite state machine is proposed. Thirdly, with the help of a Metal-Oxide-Semiconductor Field-Effect Transistor (MOSFET), the PJN is integrated with the drive circuit. The drive circuit of PJN uses an energy storage inductor to replace the current limiting resistor of the traditional drive circuit, which can not only limit the forward charging current of the PJN and reduce energy loss but also can use the energy absorbed from the low-voltage power supply to adaptively boost the power supply of the PJN to the high voltage required for working conditions. The simulation results show that the new PJN drive circuit has an adaptive self-boost function. The PWM signal modulated by the fuzzy PI double closed-loop control algorithm can efficiently and accurately control the adaptive boost power supply and the voltage across the PJN. The mode of the circuit can be correctly switched through the sequential logic of the finite state machine and realize the energy recovery function.

Design of Three Variable Camera Lens Control Circuit Based on C8051F311

A three variable lens control circuit based on C8051F311 is designed to solve some problems at the scene such as low precision or difficult quality control. In this system, the C8051F311 is used as the control, first a PWM signal is output, then the PWM signal through a RC filter circuit, finally through a signal processing circuit composed of comparator chip TL064 and amplifier IC TDA2030A to control the brushless DC motor, based on above all, the control of the lens is realized. At the same time, the circuit parameters are designed by using Multisim to simulate the circuit. The practice shows that the system has simple structure, convenient speed regulation and stable operation.

Tunnel Lighting Intelligent Control System Based on Ambient Light Ratio

Based on the research problems of modern tunnel lighting control technology, a tunnel lighting intelligent control system based on ambient luminosity ratio is designed, which is characterized by “car close lights bright, car passing lights dark”, intelligent analysis of system failures, etc. The core technology is LED Tunnel light group brightness automatic adjustment, python data analysis, etc. The design of the core control unit of the system is based on the STC89C52 chip, which uses the numpy module in python to matrix the data in the database through the information collected by the sensor (the light intensity inside and outside the tunnel, the traffic condition of the vehicle in the tunnel, and the working condition of the tunnel lighting equipment, etc.) Level storage and use principal component analysis and other algorithms to perform a large number of calculations and processing on the obtained data. The controller generates a corresponding PWM signal to control the brightness of the LED tunnel light group to solve the problem of excessive lighting or insufficient brightness; through other controls The components exchange information, and the downstream controller performs calculation and processing according to the control instructions sent by the previous stage and the real-time signals detected by the sensors to realize the selective brightness and automatic brightness adjustment of the tunnel section lighting, and finally achieve intelligent control, energy saving and emission reduction the goal of. In addition, we use the seaborn library and matplotlib library in python to visually display the obtained tunnel lighting equipment working condition data, and send the results to the relevant road management department. This will play an important role in greatly improving the efficiency of activities such as equipment maintenance, collecting equipment work information, and optimizing the work structure of road management. To a certain extent, it is conducive to the implementation of specific work of relevant departments.

Implementation of an FPGA-Based Current Control and SVPWM ASIC with Asymmetric Five-Segment Switching Scheme for AC Motor Drives

This paper presents the design and implementation of an application-specific integrated circuit (ASIC) for a discrete-time current control and space-vector pulse-width modulation (SVPWM) with asymmetric five-segment switching scheme for AC motor drives. As compared to a conventional three-phase symmetric seven-segment switching SVPWM scheme, the proposed method involves five-segment two-phase switching in each switching period, so the inverter switching times and power loss can be reduced by 33%. In addition, the produced PWM signal is asymmetric with respect to the center-symmetric triangular carrier wave, and the voltage command signal from the discrete-time current control output can be given in each half period of the PWM switching time interval, hence increasing the system bandwidth and allowing the motor drive system with better dynamic response. For the verification of the proposed SVPWM modulation scheme, the current control function in the stationary reference frame is also included in the design of the ASIC. The design is firstly verified by using PSIM simulation tool. Then, a DE0-nano field programmable gate array (FPGA) control board is employed to drive a 300W permanent-magnet synchronous motor (PMSM) for the experimental verification of the ASIC.

An Enhanced Spice and 3D Modelling for Standard Servomotors

Servomotors are widely used and well known by hobbyists for control of small scale radio controlled boats, cars or planes. The control is done using a simple PWM signal modulation, easily compatible with a 2 or 4 channels remote control system. As hobbyists are generally simple users, a light knowledge is generally enough to drive this kind of motor. However, in some electronic applications, we need deeper information on servomotors behaviour. Unfortunately, servo manufacturers never give detailed datasheet and no information is available on various WEB sites. Thus, we present in this paper, a SPICE modelling for hobbyist servomotor. Simulation and practical experimentations are done to validate the modelling. Finally, an additional lively 3D modelling is proposed and a concrete didactical application is described before conclusion

Single Phase Inverter with Power Monitoring using Arduino

The inverter is an electronic device which able to convert DC electricity into AC electricity. In the development of renewable energy resources, for example, solar power plants, inverters are needed. In this research, an inverter is made by real-time power monitoring. The inverter is made using unipolar PWM modulation and a full H bridge topology. PWM signals are generated from Arduino microcontrollers that will control MOSFET switching. Power monitoring is done by installing a DC voltage sensor and INA219 DC current sensor while on the output side using the PZEM 004t (v3) sensor and results will be displayed on the OLED. The experiment was successfully carried out by producing an approaching sine wave signal with a frequency of 50 Hz and 220 V AC voltage. The efficiency of the inverter is low because of loss from the transformer which has a no-load efficiency of 68.7%. When the 15W load has installed the efficiency of the inverter is 31.83% and when the 20W load has installed the efficiency of the inverter is 34.72%. Finally, when the smartphone’s charger is installed the total efficiency was 49.96%.

Design of Modified Counter based PWM generator for closed-loop DC-DC Voltage Regulation

This paper proposes the design of a novel Modified Counter based Digital Pulse Width Modulation generator to analyze the performance of the closed-loop DC-DC buck converter. The closed-loop DC-DC buck Converter uses the Proportional Integral controller to regularize the output voltage and the bio-inspired algorithms namely Particle Swarm Optimization and Ant Colony Optimization are considered for the generation of the optimal values for the PI gains namely KP and KI. Conventionally, the switching of the buck converter is controlled by the PWM signals that exhibit complexity in design. The updated Digital Pulse Width Modulation techniques were suitable for voltage regulation at the cost of high clock frequency requirement, increase in the design area for real implementation, and the trade-off between the switching frequency and the component size of the buck converter. To overcome these, the modified Counter based Digital Pulse width modulation that generates the high switching frequency DPWM is developed in HDL. Then the proposed technique is validated in the closed-loop PI-based DC-DC buck converter using the System Generator MATLAB SIMULINK. To regularize the voltage output, the PI controller is included along with the optimization algorithms such as Particle Swarm Optimization and Ant Colony Optimization to optimize the PI gains. The time transient analysis of the proposed method exhibits improvement in the ACO based design compared to the PSO based method. The power and area are manipulated by using the Cadence and Xilinx tools