Power Control Circuit Research Articles

Improving the torque direct control method of the asynchronous motor in the converter using the active rectifier

The frequency converter study has shown that controlled rectifiers, also known as active rectifiers, have many advantages over uncontrolled rectifiers (diode bridges). The frequency converter with an active rectifier ensures that the input current is sinusoidal, the power factor is 1, the DC voltage constant at the output, the energy exchange according to bidirectional is between the load and grid. The voltage oriented control for the active rectifier will measure the grid voltage and use current control circuits or instantaneous power control circuits. The paper analyses the advantages of using the method of controlling the current in the rectifier circuit when working with the three-phase motor load. The torque direct control method of the motor is enhanced by selecting a new switch table of the voltage vector. The combining power, an active rectifier circuit, inverter, motor, and load create a complete electric drive system with improved working efficiency. The research results were verified by Matlab&Simulink software.

Implementation of a 3.5 kW resistive load bank for a single-cylinder diesel engine test bench

This article presents the implementation of a 3.5 kW resistive load bank applied to a four-stroke single-cylinder diesel engine test bench that operates with an alternator. With this experimental test bench, it is possible to perform mechanical, thermodynamic, and polluting emissions studies in compression-ignited or induced internal combustion engines. Applying the quantitative research methodology, the design of the electric charging system is carried out. Power control circuits and safety elements are designed for the load back. CAD software is used to design the structure and casing considering anthropometric measurements. Also, finite element analysis (FEA) is incorporated to verify the structural and thermal design criteria. he implementation of an electrical and instrumentation acceleration system for sensing power and torque in low-displacement engines showed a measurement error of less than 1%. Similarly, the FEA allowed to quantify the maximum efforts and guarantee a safety factor above 5. With the characterization of the implemented sensors, a correlation coefficient of up to 99.97% was achieved. The power measurement displayed an error lower than 3%, which leads to a high characterization capacity of any thermal machine with equal power or less than the designed one.

Design and Implementation of Boost Voltage Doubler for Maximum Power Point Tracker Application Using STM32F1038CT

Photovoltaic is an absolute device in the solar power plant system. A DC-DC converter with a maximum power point tracker (MPPT) algorithm is required to obtain the maximum power of photovoltaic. In general, solar power plant applications used a two-stage converter: the first stage is boosting DC-DC converter, and the second stage is the multilevel Inverter. Boost DC-DC converter is usually implemented singly, which causes many boost DC-DC converters to be implemented in a solar power plant application. The voltage doubler type boost DC-DC converter proposed in this paper is to simplify the circuit so that there is only one converter in a solar power plant application. This converter principle combines two conventional boost converters, which are integrated into one so that the power circuit and control circuit form become simpler. This proposal is verified through computation simulation and hardware design using the STM32F1038CT microcontroller for the final verification. The efficiency algorithm of the simulation is 99.7%, and the hardware experimental is 85.65%

Wireless Control System Design for Coal Transportation Plant Based on Two-part Tariff System

Under the current tariff policy, large industrial users, such as coal transportation companies, are typically charged a two-part tariff. This tariff policy limits the maximum value of the average load every fifteen minutes for a month, with an additional charge for electricity consumption when the threshold is exceeded. The article proposes a wireless monitoring and control system for coal transportation plants in response to this policy. First of all, the backup power supply and control circuit were added to the electric equipment of the coal transportation plant. Then build a ZigBee wireless sensor network, terminal and relay connected, coordinator and PLC connected. Finally, when the sensor monitors the actual electricity consumption is about to reach the maximum value set in the PLC, PLC sends a command through the ZigBee to control the relay action and switch to the backup power supply. The experimental results show that the wireless control system has a clear structure and effective strategy, which can reduce the basic electricity cost of the coal transportation plant.

A transceiver frequency conversion module based on 3D micropackaging technology

The idea of Ku-band transceiver frequency conversion module design based on 3D micropackaging technology is proposed. By using the double frequency conversion technology, the dual transceiver circuit from Ku-band to L-band is realized by combining with the local oscillator and the power control circuit to complete functions such as amplification, filtering and gain. In order to achieve the performance optimization and a high level of integration of the Ku-band monolithic microwave integrated circuits (MMIC) operating chip, the 3D vertical interconnection micro-assembly technology is used. By stacking solder balls on the printed circuit board (PCB), the technology decreases the volume of the original transceiver to a miniaturized module. The module has a good electromagnetic compatibility through special structure designs. This module has the characteristics of miniaturization, low power consumption and high density, which is suitable for popularization in practical application.

Research on Losses of PCB Parasitic Capacitance for GaN-Based Full Bridge Converters

The utilization of wide band-gap semiconductor devices provides the possibility of higher switching frequency and power density for power converters. However, the influence of parasitic parameters becomes more significant. It deteriorates the converter performance and leads to extra loss. In this article, the extra loss caused by the parasitic capacitance of printed circuit boards (PCBs) is studied. The mechanism is explained, and the model of full bridge topology with PCB parasitic capacitance is proposed as an example. Both the capacitance in power loops and control circuits are considered in the proposed model. Besides the capacitive loss in power loops, losses are also introduced by the capacitive coupling between the power and control circuits due to the potential pulsation of the control ground. This potential pulsation is analyzed and the calculation method of corresponding losses is presented. The formation of PCB parasitic capacitance is analyzed in detail and corresponding layout optimization methods are proposed. Theoretical analyses are verified on a gallium nitride based full bridge prototype with calorimetric loss measurement. The comparison of calculated and measured losses is presented, which shows a switching loss deviation of 26% without the consideration of parasitic capacitance and a 40% reduction on the extra losses after the proposed optimization.

Modelling of adaptive power management circuit with feedback for self-powered IoT

In general, self-powered sensor networks/Internet of Things (IoT) are equipped with a power management system and use a timer as a reference for the device’s actives time, both using an internal timer and an external timer. The system is less efficient because it requires that there are parts that continue to function when the device is in sleep mode. In addition, the amount of harvested energy also influenced by many factors with an uncertain amount. An IoT self-powered system that uses a timer as an active interval reference will encounter problems when the amount of system energy demand is greater than the harvested energy. This paper presents an adaptive power management system equipped with feedback for self-powered IoT for room temperature and humidity monitoring applications. The power management system can provide adaptive active intervals based on the harvested energy capacity. Microcontrollers send feedback to the power management circuit at the end of each cycle. The power management circuit immediately disconnects the controller circuit from the energy storage’s component (supercapacitor) so that energy used efficiently. Several methods of minimizing the energy consumption of the device are also applied to provide optimal results. The research method begins with system modelling, including an energy harvester circuit, power management, and controller. The research scenarios include energy harvester performance tests, calculating the energy requirements of the power management and controller circuit, and validating research results. Overall, the system can work well, the active interval/data transmission of 14.41 seconds to 22.34 seconds in a room with a light intensity of 800 lux to 1000 lux.

Enhancing die level static fault isolation on power gated devices

Modern SoC design incorporates power management circuits to minimize standby leakages of digital logic circuitry. This isolates the logic blocks from being directly powered by the IC's pad level power supply and ground. As a result, die level static fault isolation became ineffective even for gross defects that are shorting the power lines in the logic blocks due to gated supply. From the foundry standpoint, fault isolation on such devices are even more challenging without the product knowhow, device specific hardware and test program to properly condition the power management circuits. An alternative method is to bypass the power control circuits through microprobing on the top metal traces to directly supply power to the logic blocks. However, the key challenge to this method is the means to differentiate between power gated and non-gated devices and then subsequently verify the relevant power traces to microprobe especially in the absence of layout. This paper illustrates 4 different approaches to overcome this challenge and achieve static fault isolation success on power gated devices. Successful applications of this approach to localize gross defects resulting in short/leakage failures and subtle defects resulting in memory/logic functional failures will be described.

A PM1, PM2.5, and PM10 Airborne Particle Detector With Laser Illumination Stabilized by Optical Feedback

This paper presents a read-out integrated circuit (ROIC) for PM1, PM2.5, and PM10 airborne particle detector with a laser diode. The ROIC has a monitoring photodiode, which provides negative feedback through an automatic power control circuit. This adjusts the driving current to the laser diode, and thus stabilizes the illumination level. Offset compensation circuit in analog front-end eliminates the large offset voltage introduced by stray light reaching the measuring photodiode. A digital back-end analyses each pulse to determine the corresponding particle size, and also linearizes the response, which would otherwise drop off for smaller particles. The ROIC was fabricated in a $0.18~\mu \text{m}$ CMOS process. It has an area of 6.27 mm2 and draws 10 mW at 5 V. The ROIC is incorporated in a particle detector which is tested against an aerosol spectrometer. For particle concentrations up to $100~\mu \text{g}/\text{m}^{{3}}$ , this detector was found to have an accuracy of $\pm ~10~\mu \text{g}/\text{m}^{{3}}$ for PM10 and PM2.5, and $\pm ~15~\mu \text{g}/\text{m}^{{3}}$ for PM1. At higher concentrations, up to $1000~\mu \text{g}/\text{m}^{{3}}$ , the corresponding accuracies are ± 5 % and ± 10 %. Within the temperature range of 0 °C to 50 °C, the effective resolution of the detector changes only from 8.78 bits to 8.97 bits.

Modeling and stability study of a high frequency and high efficiency photovoltaic DC boost converter

Many practical photovoltaic power generation systems with higher output voltage levels rely on photovoltaic DC boost converters with high frequency and high efficiency, which performance directly affect the conversion efficiency of photovoltaic power generation systems. This paper investigates a high-frequency and high-efficiency photovoltaic DC boost converter, which adopts the Boost full-bridge isolation circuit topology with active clamps. The conductance increment method is used as the maximum power point tracking algorithm. The small signal models of its power circuit and control circuit are established to obtain the system model and analyze its stability. The simulation results indicate that the ripple coefficient of output current is less than 3%, and the ripple coefficient of output voltage is less than 5%, which meets the stability requirements.

Mechanical–electrical–pneumatic systematic design exploration of hexapod robot experimental prototype

Aiming at the problem of the detect and rescue in the coal mine with the leaking vas, a type of pneumatic hexapod explored robot which uses a high pressure nitrogen cylinder as the power producer is designed. The leg mechanism is designed with three degrees of freedom, the straight line walking and turning gaits are planned, which are testified by the virtual prototype. The control loop of the cylinder is designed with the magnetic valve with three positions and five paths. The air bottle, the reducing valve, the general follow control part (GFC) the magnetic valve with three positions and five paths, the cylinder are selected and the air supply loop of the hole machine is designed, the 3D model of the hole machine is built which is used to confirm the installing form of the hole body. The experimental prototype is obtained at last. The power supply and control circuits of the magnetic valves are designed, the control series is written on the Arduino single chip. The experiment of the leg swing of the robot on the stage is proceeded which verifies the correctness of the design.

Design of Simulated Circuits for the Releasing Device Tester

Aiming at the function test of the releasing device, the encoding circuit was designed by using circuit simulation method, and the full function test of the device was realized by generating analog signals. The timing circuit, power control circuit and band switch circuit were designed by using sequential logic and micro processing technology, and the portable test device for the placement device was designed and implemented. The test results show that the performance of the tester is stable, the test items are complete, and the indicators meet the design requirements.

Sliding-Mode Approaches to Control a Microinverter Based on a Quadratic Boost Converter

A comparative analysis of the dynamic features of a step-up microinverter based on the cascade connection of two synchronized boost stages and a full-bridge is presented in this work. In the conventional approach the output of the cascaded boost converter is a 350–400 DC voltage that supplies the full-bridge that makes the DC-AC conversion. Differently from the classical approach, in this work, the cascaded boost converter delivers a sinusoidal rectified voltage of 230 Vrms to the full-bridge converter that operates as unfolding stage. This stage changes the voltage sign of one of every two periods of the rectified sinusoidal signal providing the final output AC waveform. In contrast to a classical full-bridge inverter, the unfolding stage lacks output filter, and has zero order dynamics. Thus, the approach presented here implies a second order dynamics reduction that will be increased applying sliding motions to control the system. After introducing the inverter circuit, two sliding control alternatives, input current mode and pseudo-oscillating mode, are presented. Both alternatives are analyzed, simulated, and verified experimentally. Furthermore, detailed description of the microinverter power stage and control circuits are also given.

A Novel Simple Differentiator Circuit Based on Carbon Nano Tube Field Effect Transistors Voltage Difference Transconductance Amplifier

: This paper brings in a new design, namely, voltage mode differentiator with an active element, Carbon Nanotube Field Effect Transistors Voltage Difference Transconductance Amplifier (CNVDTA). The circuit thus proposed needs one Carbon Nanotube Field Effect Transistors Voltage Difference Transconductance Amplifier (CNVDTA) element and a single capacitor. While fabricating IC’s in VLSI design, the proposed circuit proves more adaptable and applicable with the anticipated results. Methods: The proposed CNVDTA based voltage mode differentiator in CNFET technology was simulated at 32 nm at a voltage supply of ±0.9 V using the Cadence Virtuoso CAD tool. Results: It is also reported that the proposed circuit would function with ±0.9 V supply voltage and would also take care of the bias current of the order of 150 µA. Further, on the part of the transconductance (gm), it is electronically tunable with the help of bias current. Conclusion: The CNVDTA based differentiator has been found to be very useful in the triggering circuit of CRO’s, wave shaping circuits, power control circuits etc. It is also found useful in detecting the high-frequency components in the input signals.

The multilevel inverter with clamped-diode

<p>In this study, the author analyzes the advantages and disadvantages of multi-level inverter compared to the traditional two-level inverter and then chose the suitable inverter. Specifically, the author analyzes and designs the three-level inverter, including the power circuit design and control circuit design. All designs are verified through the numerical simulation on Matlab. The results show that even though the three-level inverter has a low number of switches (only 12 switches), but the quality is very good: the total harmonic distortion is small; the output voltage always follows the reference voltage.</p>

“Digital” Approaches to Expanding the Dynamic Range of Broadband Microwave Receivers

This article considers the main factors limiting the dynamic range of broadband microwave receivers. We suggest system-technical approaches to engineering design. These approaches consist of the automatic regulation by built-in means of operating mode of elements of receiving and heterodyne tracts. We demonstrate the results of the study of the infradyne converter with an extended real dynamic range. It is concluded that it is expedient to use digital automatic power supply and control circuits in broadband microwave converters. Petrov S. A. “Digital” Approaches to Expanding the Dynamic Range of Broadband Microwave Receivers. Ural Radio Engineering Journal . 2019;3(4):356–368. DOI: 10.15826/urej.2019.3.4.002

Multi‐channel VSI fed large variable speed asynchronous hydro‐condenser: fault analysis, fault diagnosis and fault tolerant control

Multi-level voltage source inverter (VSI) fed doubly fed induction machine (DFIM) has gained prominence in large rated hydro-generating unit (HU) since it provides part load operation with reduced power converter rating and high dynamic stability. Power converters connected in rotor side control real and reactive power of the unit. This study discusses the condenser operation of variable speed HU (250 MW), to be commissioned in Tehri plant (India), with the power flow diagram. Further, it provides dynamic behaviour and survivability status of the DFIM unit during power converter and control circuit faults where power converter redundancy is not available in large rated DFIM unit. Economic analysis of 250 MW HU under power converter and control circuit failures are also investigated. The present work also explores fault tolerant operation of a 250 MW DFIM unit at open switch fault in converters to increase the continuity of the unit operation which provides additional 2% of reactive power support to the grid compared to the DFIM without power converter redundancy operation. Open switch fault is detected through Park's vector phase currents technique and variation in DC link voltage. The computer simulation results are validated in an experiment carried on 2.2 kW DFIM in the laboratory.

Decentralized Control for Fully Modular Input-Series Output-Parallel (ISOP) Inverter System Based on the Active Power Inverse-Droop Method

Input-series-output-parallel (ISOP) inverter systems are suitable for the high-input-voltage and large-output-current applications. In this paper, an active power inverse-droop control method is presented for the ISOP inverter system, in which the polarity of active-power feedback is inversed to be positive compared with the traditional droop control while the reactive power droop is still adopted to achieve voltage and power sharing of the system. The modularity and reliability of the system are greatly improved due to that both power circuits and control circuits of the constituent modules are self-contained and independent. The input voltage sharing and output current sharing can be well achieved without the sampling of input voltage, so the high-voltage sensors are eliminated. Thus, the cost and volume of the system can be reduced. The operational principle of the active power inverse-droop control is introduced and the detailed system design is presented based on the proposed control scheme. The stability analysis and the guideline for power sharing loop design are also provided. Finally, simulation and experimental results of a two-module ISOP inverter system verify the effectiveness of the proposed control strategy.

Mitigation of Power Quality Issues Due to High Penetration of Renewable Energy Sources in Electric Grid Systems Using Three-Phase APF/STATCOM Technologies: A Review

This study summarizes an analytical review on the comparison of three-phase static compensator (STATCOM) and active power filter (APF) inverter topologies and their control schemes using industrial standards and advanced high-power configurations. Transformerless and reduced switch count topologies are the leading technologies in power electronics that aim to reduce system cost and offer the additional benefits of small volumetric size, lightweight and compact structure, and high reliability. A detailed comparison of the topologies, control strategies and implementation structures of grid-connected high-power converters is presented. However, reducing the number of power semiconductor devices, sensors, and control circuits requires complex control strategies. This study focuses on different topological devices, namely, passive filters, shunt and hybrid filters, and STATCOMs, which are typically used for power quality improvement. Additionally, appropriate control schemes, such as sinusoidal pulse width modulation (SPWM) and space vector PWM techniques, are selected. According to recent developments in shunt APF/STATCOM inverters, simulation and experimental results prove the effectiveness of APF/STATCOM systems for harmonic mitigation based on the defined limit in IEEE-519.

Dynamic Performance of Pumping Mode of 250 MW Variable Speed Hydro-Generating Unit Subjected to Power and Control Circuit Faults

Doubly fed induction machine (DFIM) is increasingly being preferred in sites where there is large variation in water head (e.g., Tehri hydropower complex in India having water head variation from 130 to 230 m), as it offers high dynamic stability and better energy efficiency at part loads. Smooth starting, unity power factor, and better rotor current profile are the reasons; back-to-back voltage source converters are used in rotor side of the machine. Speed and power factor of DFIM are controlled through power converters in accordance with surplus power available in grid and water head of dam. This paper presents dynamic behavior of a 250 MW DFIM hydro-generating unit, to be commissioned in 1000 MW Tehri pumped storage plant, operating in pumping mode. Further, the performance of pumping operation of DFIM is assessed under power converter and control circuit failures. Persevere ability of the machine is analyzed based on performance measures: Speed, current, reactive power consumption. From the analysis, energy storage loss of about 66.61 MU/year is estimated in a 1000 MW plant due to the inadequate power and control redundancy. A 2.2 kW DFIM is experimented at laboratory level to support the simulation.