Traditional Power Supply Research Articles

A High-Precision and High-Efficiency PMSM Driver Based on Power Amplifiers and RTSPSs

A novel topology based on linear power amplifiers (PAs) and real-time sinusoidal voltage-adjustment power supply systems (RTSPSs) for a permanent magnet synchronous motor (PMSM) drive system is proposed in this article. Here, PAs are applied to achieve high-precision motor drive control and minimize the motor torque ripple and harmonic loss caused by nonlinearities of the inverter in traditional space vector pulsewidth modulation. Meanwhile, in order to improve the conversion efficiency of PAs, the traditional dc power supply system of PAs is replaced by the RTSPSs, which is based on the wide-band-gap devices. The experimental results show that the efficiency of PAs in the motor system is increased from 58.88% to 79.25% and the fluctuation of the motor speed at a given speed of 2 r/min is reduced from 27 to 0.5 r/min.

Analysis of Fault Characteristics of AC Line Interconnected with MMC

Affected by the control strategy of suppressing the negative sequence current and limiting the amplitude of the positive sequence current after the MMC fault, the fault characteristics of the converter side of the AC line interconnected with the MMC show that the negative sequence current is very small and the positive sequence current amplitude is different from the rated value Compared with the fault characteristics of the traditional power supply, there are obvious differences between the minor characteristics and the fault characteristics of the traditional power supply. And it has been simulated and verified on the RTDS simulation platform.

Design of monitoring system for redundant communication power supply based on ZigBee

Aiming at the problems of poor maintenance effect and large measurement error of traditional communication power supply monitoring system, a redundant communication power supply monitoring system based on ZigBee is designed. The sensor and power supply cable are installed, the battery working state parameters are collected and cleaned, compressed and fused. The MSP430F149 single chip microcomputer is used to realize the high-speed processing of field information and optimize the configuration of hardware structure. The software maintenance process of the complete redundant communication power supply monitoring system is designed. The logic editing technology is used to correct, adjust and improve the system software. The mathematical model of hardware maintenance is established. The most reasonable monitoring and measurement of redundant communication power supply is calculated by ZigBee method to realize the effective monitoring of communication power supply. The experimental results show that the hardware operation effect of the design system is good, and the measurement error can be effectively reduced.

A Single-Stage High Power Factor Power Supply for Providing an LED Street-Light Lamp Featuring Soft-Switching and Bluetooth Wireless Dimming Capability

Light-emitting diode (LED) has the characteristics of environmental protection and energy saving, having become the lighting source of a new generation of street-light lamps. The traditional two-stage power supply for providing an LED street-light lamp is composed of an AC-DC converter with a power-factor-correction (PFC) function at the front stage and a DC-DC converter at the rear stage. The two-stage power supply for an LED street-light lamp has a large number of electronic components and costs, and the circuit efficiency is not high. Therefore, this paper presents a novel single-stage high power factor AC-DC power supply for providing an LED street-light lamp featuring soft-switching and Bluetooth wireless dimming capability through using smart tablets or smartphones to remote control the output power of the LED street-light lamp for achieving energy-saving benefits. The proposed AC-DC LED power supply integrates an interleaved buck converter circuit with coupled inductors and a half-bridge LLC resonant converter circuit into a single-stage power conversion circuit. Moreover, the coupled inductor of the interleaved buck converter circuit is designed to operate in the discontinuous conduction mode, which can naturally achieve PFC. In addition, the two power switches in the novel LED power supply have zero-voltage switching (ZVS) characteristics, which can reduce the switching losses of the power switches. The two output diodes have the characteristics of zero-current switching (ZCS), which can reduce the conduction losses of the power diodes. This paper developed a single-stage prototype circuit for providing an 144 W (36 V/4 A)-rated LED street-light lamp. According to the experimental results of the prototype circuit with an AC input voltage of 110 volts, the presented single-stage LED power supply offers high power factor (PF > 0.99), low input-current total harmonic distortion factor (THD < 3%), and high efficiency (>89%). In addition, this paper used the built-in Bluetooth wireless communication function of a smart tablet or smart phone to fulfill remote dimming control. By changing the duty ratio of the control signal, we could realize remote dimming control of 20% to 100% of the output LED street-light lamp power.

A Design Method of Compensation Circuit for High-Power Dynamic Capacitive Power Transfer System Considering Coupler Voltage Distribution for Railway Applications

Capacitive power transfer (CPT) is a promising method to solve the problems caused by the traditional Pantograph-catenary contact power supply for railway applications. In contrast, the CPT system suffers a broken risk because of the small coupling capacitor. This paper has analyzed the CPT coupler’s voltage distributions for dynamic CPT systems when high power is required in real railway applications. The triangle relationship among the coupler voltages is derived. The circuit of the CPT system to accolated the coupler voltage is analyzed. Then, the compensation parameters are given. With the adopted LCLC-CL topology, the design process is presented by considering the coupler voltages. An experimental setup is conducted to validate the proposed design method. The experimental results show that the system can achieve 3 kW output power with 92.46% DC-DC efficiency and the voltage distribution aggress well with the designed values.

Application of Traction Power Supply for Metro Rail Transit Based on Electromagnetic Sensing Technology

With the gradual acceleration of modernization, metro projects have been opened for the development and construction of urban areas. How to ensure the smooth operation of subway project in public service has become the focus of urban public safety service research. In view of this content, this paper studies the subway field of urban rail transit operation and improves the public safety of urban rail transit operation. Firstly, the factors affecting the track traction power supply are analyzed, the anti‐interference technology of ring array electromagnetic sensor is added, and the research scheme is formulated according to the track potential research standard to ensure the operation of the power supply system. Then, the electromagnetic sensor traction algorithm is used to detect the subway track power supply signal, and the working characteristics and advantages of single electromagnetic induction and double electromagnetic induction are analyzed. The experimental results show that compared with the traditional electromagnetic sensor power supply signal detection algorithm, the content of this paper can judge whether the power supply is normal according to electromagnetic induction, detect whether the subway traffic deviates from the track traction coordinates, and understand the size of the deviation from the track. It improves the efficiency of traction power supply detection, stabilizes the running track of subway traffic, and is conducive to the protection and development of urban public safety.

Design and simulation of DC regulated circuit for current source input type based on Tina-TI

In the multi-output high-voltage isolated power supply for solid-state switches, LCL resonant network is used to obtain the constant current source on the bus, and the bus current is independent of the load. Therefore, the secondary side of the toroidal transformer needs to use the current input voltage regulator circuit. When the input is a current source instead of a voltage source, the traditional voltage regulator circuit is no longer applicable. Therefore, this paper focuses on the study of dc voltage regulated circuit with current source input. Compared with the traditional linear regulated power supply, switching power supply has the advantages of high efficiency, large output power, small size, light weight and low cost. In this paper, pulse width modulation (PWM) technology is used to control the switching on and off, and UC3843 is used to design a switch type regulated power supply with small size, simple circuit, adjustable output and over voltage protection function. Tina-TI software was used for simulation analysis, and the main circuit and control circuit were built. The current source of 1.25A and 40kHz output by the secondary side of the toroidal transformer is converted into a stable 10V DC voltage source, which verified the correctness of the design. Tina-TI software can be used to analyze and design power supply with different requirements, improve power efficiency, reduce design complexity, and thus shorten development cycles.

Analysis of overcharging characteristics of a new type lithium iron phosphate battery for dc system of substation

In recent years, the number of DC power system in substation has been increasing. And the technical transformation of DC power system, fault maintenance and other workload is also on the rise, therefore dc emergency power emerged. The lead-acid battery is usually adopted for traditional DC emergency power supply. The disadvantage of lead-acid battery in volume and quality makes it difficult to realize the portability and mobility of dc emergency power. Lithium iron phosphate battery technology is the frontier technology in the rapid development period. However, the characteristics are not studied clearly. This paper studies the characteristics of lithium iron phosphate battery in different ambient temperature, operating conditions, and current of charge and discharge, analyses and summarizes the characteristics of battery charge and discharge, so as to improve the maintenance of station DC power supply system and the reliability of power supply network.

The Flexible Smart Traction Power Supply System and Its Hierarchical Energy Management Strategy

With the increasing requirements of the railway sector for electrified railways and the development of society, the traction power supply system needs to become more flexible, economic and reliable. The traditional traction power supply system has many problems due to its own topology, such as negative sequence current, load fluctuation, low utilization rate of regenerative braking energy, and inability to use the distributed generation along the railway. In order to solve these problems and make the traction power supply system (TPSS) more flexible, efficient and reliable, a novel TPSS called flexible smart traction power supply system (FSTPSS) is proposed. This traction power supply system consists of AC-DC-AC traction substation and the microgrid along the railway. It can effectively mitigate the problems of negative sequence current, improve regenerative braking energy utilization and distributed generation utilization. A hierarchical energy management strategy is also proposed here, which can effectively improve the operating economy of FSTPSS and reduce the load fluctuation of FSTPSS. And based on the actual load measurement power of a traction substation of China’s Beijing-Shanghai high-speed railway, the proposed energy management strategy has been verified for the economic improvement and load fluctuation reduction of TPSS.

Research on non-contact ultrasonic vibration assisted rotating electrical discharge machining (EDM) machine tool

Electrical discharge machining (EDM) is a nontraditional machining method by using pulsed spark discharge between workpiece and electrode to melt and remove metal. The traditional power supply method uses carbon brush and slip ring. This contact type has power supply at the contact point. Problems such as carbon deposition, leakage, and easy generation of electric sparks restrict the improvement of the rotation speed of the electrode and pose a safety hazard. The non-contact power supply technology based on the principle of electromagnetic induction can effectively solve the above problems, which can provide conditions for high-speed rotation of the electrode. In order to improve the processing quality and efficiency, this study aimed to design a small ultrasonic vibration assisted EDM machine, which can effectively avoid spark concentration and abnormal arc generation.

Analysis and Optimization of Asymmetric Wireless Power Transfer in Concrete

With the rapid development of the Internet of things (IoT) technology, the application of IoT has been expanded greatly, and the disadvantages of the traditional battery power supply have become increasingly prominent. The power supply mode limits the development of the concrete structural health monitoring network. And the application of magnetic resonance coupled wireless power transfer technology can solve the problem of power supply to sensors embedded in concrete. The corrected transmission efficiency considering the concrete conductivity is proposed which establishes the relationship between the electromagnetic field and the circuit model. And the field-circuit coupled model of asymmetric wireless power transfer system in concrete is developed. The effects of radial offset and axial dislocation on the transmission efficiency at different concrete conductivity are further analyzed. The relationship between the resonant frequency and the transmission efficiency in different concrete conductivity is analyzed, and an optimization scheme is proposed to improve the transmission efficiency. Finally, the experimental setups are established, and the theoretical analysis is verified. The conclusions cannot only break through the bottleneck of the scale of the concrete structural health monitoring network but also further releases the application potential of IoT.

Improvement of Quadruple Structure and Optimization of Control Algorithm for Co-Phase Traction Power Supply System

Co-phase power supply is one of the key technologies to solve the technical bottlenecks such as electrical phase separation zone, poor power quality and defects in structure and control algorithms in traditional traction power supply systems and single co-phase power supply schemes, and an inevitable way to realize the development of electrified railways in the direction of safety, high speed and heavy load. Based on the single co-phase power supply technology, a novel quadruple co-phase power supply scheme with negative sequence elimination and to suppress reactive power and harmonic better for the two aspects of the system structure improvement and control algorithm optimization is proposed by combining the technologies of power system flexible transmission grid-connected and multiple inverters. Finally, the simulation model for the novel co-phase traction power supply system was designed and built, and the present method was verified by a set of simulation experiments so as to obtain the expected results.

ANALYSIS OF INFORMATION CONDITIONS OF FORMATION OF STRUCTURAL-LOGICAL MODEL OF EMERGENCY MANAGEMENT IN THE CONDITIONS OF ABSENCE

The paper considers the problem of accidental destruction of power lines due to external factors, which led to the de-energization of large areas for a long time. Breakdowns can be caused by both mechanical damage and natural disasters - floods and earthquakes and more. As a rule, as a result of an emergency situation, the level of energy supply of large areas decreases. An important methodological aspect in studying the quality of the electrical network is the allocation of hierarchical levels of consideration. Thus, the authors consider the lowest level of functioning of the electrical network, namely the power supply of the emergency response system. Such circumstances, in turn, can lead to the emergence and development of emergencies that lead to significant casualties and destruction. It has been established that some accidents have led to power outages for more than one day. The analysis of features of work of emergency counteraction systems which are used on objects in the conditions of damage of electric networks is carried out. Devices of emergency counteraction of domestic production which have found wide application on objects and continue to be improved and let out are considered in work. Approaches to the use of imported emergency response devices, in terms of operation and installation, are almost the same, as they must meet the requirements of those regulations that are used in Ukraine. It is established that redundancy of power supply of such systems at the expense of rechargeable batteries allows to carry out their uninterrupted work no more than 24 hours. That is, if the power supply of emergency response systems from the traditional power supply network is not restored within 24 hours, such systems will stop working, which may lead to an emergency becoming an emergency. Thus, the further work of the authors will be aimed at finding a way to back up emergency response systems in the event of a power outage from the traditional power grid for a time exceeding the possibility of power supply from the battery. Keywords: emergency destruction, emergency, power grid, emergency response systems, backup power supply.

Wearable triboelectric nanogenerators for biomechanical energy harvesting

With compelling features of flexibility, conformability, and user friendliness, wearable bioelectronics have undergone tremendous development on account of miniaturization and multifunction advancements which could cater to the development trend of Internet of Things (IoT) and fifth-generation wireless technology. However, powering wearable bioelectronics sustainably and pervasively is beyond the capability of traditional power supply systems and remains a challenge and highly desired. By using the coupling effect of contact electrification and electrostatic induction, triboelectric nanogenerators (TENGs) were demonstrated to efficiently convert irregular and low-frequency biomechanical energy from human body movements into electrical energy for the sustainable powering of wearable bioelectronics. In this article, the latest representative achievements of wearable TENGs for electricity generation are comprehensively reviewed with the order of the accessible biomechanical energy on the human body from head to feet. This review not only covers the fundamental working mechanism, rational structural design, selection of the tribo-materials, and fabrication process of wearable TENGs, but also investigates the movement patterns and characteristics of each part of the body, as well as its feasibility and convenience for electricity generation. Finally, perspectives and challenges regarding wearable TENGs at present are discussed. • It gives a comprehensive review of wearable TENGs for on-body electricity generation. • We reviewed the field with the consideration of movement patterns and characteristics of each body part. • Challenges and problems are discussed to advance the field development.

Renewable sources of energy in distributed power generation

Russia as the leading exporter of traditional energy resources is considering renewable energy sources (RES) as autonomous sources of energy, being the basics of a new direction which is being developed intensively now – distributed power generation. In autonomous energy systems based on RES power generation of RES is reserved by means of traditional power supplies. In this case there is a task to create a tracking inverter transforming direct current (DC) into alternating current (AC) according to characteristics of a parallel operating AC generator. An inverter designed in Bauman Moscow State Technical University can successfully solve this task and by means makes it real to connect AC and DC generators in order to sum up their capacities in a single electric system.

Realization of wireless charging in intelligent greenhouse with orthogonal coil system uniform magnetic field

The improvement of the sensor power supply system in intelligent greenhouse is a research hotspot at present. In intelligent greenhouse environment monitoring demand is high, the traditional cable power supply volume is big, poor security and inconvenient to the characteristics of the paper by using the principle of the wireless power supply, design a kind of orthogonal magnetic field, the Transmitting coil and Repeating coil to receive the mutual inductance coil superposition to satisfy the sensors in the power supply requirements of different spatial location, and greatly reduces the power supply equipment covers an area of. The theoretical circuit diagram is given and the theoretical analysis and formula derivation of uniform magnetic field are performed. Mathcad was employed to simulation analysis of Receiving coils in different states, and Maxwell was used for comparison of hypnotic field cloud images. At the same time, the influence of different relative positions on the receiving power of wireless power transmission system is tested and discussed, and the method to improve the wireless power supply transmission efficiency of smart greenhouse sensor is explored. Finally, the feasibility of the system is verified by simulation and experiment.

Development of a superconducting transformer for high current conductor testing

Critical current (Ic) tests on superconducting conductors require currents on the order of tens of kilo-amperes in combination with sub-microvolt resolution voltage measurements. Instead of traditional expensive DC power supply and complicated current leads, a superconducting transformer has been developed to feed the test sample with current up to 30 kA. The transformer consists of two concentric layer-wound superconducting solenoids with the primary coil inside the secondary. In order to reduce the influence by stray field of background magnet and transformer, a hall array with two hall sensors symmetrically distributed around the secondary conductor is used to achieve accurate secondary current measurement. This paper describes the design and manufacturing of transformer, including accurate secondary current measurement method. The first test results are also presented. The superconducting transformer system enables fast, high resolution, economic and safe tests of high current conductors.

Analysis of Transmission Power and Efficiency of Side-Mounted Inductive Power Supply System for Metal Rotary Shafts

The online detection of metal shaft parameters, such as torque, power and deformation, is widely applied in engineering projects. The power supply of metal shafts is the key to the detection reliability and practicality. However, traditional slip ring and battery power supply are limited in reliability and service life. In this paper, a side-mounted inductive power supply system for the rotating metal shaft is designed by using a Utype core. The equivalent reluctance and circuit models of the system are analyzed, and the methods of improving the coupling coefficient and transmission efficiency are proposed from theoretical analysis. Through the finite element simulation analysis of the system, the general relationships between the transmission power and efficiency of the system and the number of coil turns, the working frequency and the load are analyzed. The accuracy of theoretical analysis and simulation analysis is verified by the practical power transmission experiments. This paper provides a novel and reliable power supply method for inductive power supply of rotating equipment, and enriches the solutions of rotating power supply.

Linear attenuation current input mode: A novel power supply mode for electrochemical oxidation process

At present, the most considerable defects of electro-catalytic process lie in low current efficiency and high specific energy consumption. Besides electrodes, current parameters and reaction system, the power supply mode is also of great significance for optimization of electrochemical oxidation. Traditional power supply modes include constant voltage mode, constant current mode and pulse mode. Based on the concept of limiting current density, this paper proposed a linear attenuation power supply mode and set up three different application modes. This novel power supply mode is to make the current input into the electro-catalytic system continuously decay over reaction time, which were simulated adopting a computer-controlled programmable DC power. Acid Red G, phenol, guaiacol, salicylic acid and actual water samples from sewage treatment plant were taken as the target organic substance, furthermore, the advantages and disadvantages of three linear attenuation modes and traditional constant current mode were compared through electrochemical oxidation experiments in terms of varying evaluation parameters. The experimental results indicated that Mode I (same initial current density, different attenuation rates) obtained higher average current efficiency and lower specific energy consumption than constant current mode in order to achieve the equivalent degradation performance. However, the decolorization rate and COD removal rate of Mode I were lower than those of traditional constant current mode. Mode II (direct linear attenuation) and Mode III (constant current before linear attenuation) were superior to the traditional constant current mode with the same input total power in the aspects of decolorization rate, COD removal rate, average current efficiency, specific energy consumption and etc. Those results were further verified in different organic matters wastewater samples and actual wastewater samples. For actual wastewater samples treatment, the experimental average current efficiency and specific energy consumption of Mode II (6.96 %, 0.237 kWh·gCOD-1), Mode III (8.89 %, 0.209 kWh·gCOD-1) and traditional constant current mode (5.18 %, 0.343 kWh·gCOD-1) indicated that, in practical engineering, more preferable current efficiency and lower energy consumption can be achieved by Mode II and Mode III over traditional constant current mode. Those demonstrated that the newly proposed linear attenuation mode (especially Mode III) can effectively improve the current efficiency of electrochemical oxidation process and reduce the specific energy consumption.

Key Technical Research on Power Electronics and Information Transmission System

Power electronics is a new technology of power transmission and control. Compared with the traditional power transmission, non-contact power transmission has the advantages of low wear rate, safety, reliability, convenience and flexibility. In this way, it avoids the problems of friction, wear, aging and so on in the traditional power supply mode, saves a lot of wires, makes up for the shortcomings of the traditional power transmission mode, and has a wider application range. Therefore, it is of great practical significance to study the key technology of power electronic information transmission for promoting the intelligent development of power transmission in China.