Auxiliary Power Supply Research Articles

Corrections to “A Scalable Self-Powered Balancing Circuit for High-Step-Down-Ratio Auxiliary Power Supply”

Corrections to “A Scalable Self-Powered Balancing Circuit for High-Step-Down-Ratio Auxiliary Power Supply”

A flexural-beam-type wide-frequency piezoelectric energy harvester for vertical shaft lifting system vibration monitoring

Abstract The coal mine lifting system may experience serious safety accidents due to severe problems with the bucket guides and rolling guide shoes. A piezoelectric energy harvesting (PEH) device for vibration sensor monitoring of shaft lifting system is proposed for the first time to monitor health of shaft lifting system. However, there are differences in the vibration frequencies, the working conditions are complex, leading to issues such as low energy recovery efficiency of the PEH and difficulty in achieving self-powered. To enhance PEH adaptability and reliability, a specifically designed flexural-beam-type wide-frequency piezoelectric energy harvester(FBT-WF-PEH) and a method of achieving real-time vibration monitoring through auxiliary power supply have been proposed. The results indicate when the excited frequency is 17Hz, the highest external output voltage is 11.2V, and under an external load of 17.5kΩ, the maximum output power is 7.168mW, demonstrating a good performance in terms of output power, and energy harvest bandwidth. The captive power supply test verified the PEH can utilize the vibration environment to achieve auxiliary power supply for monitoring systems under working conditions, which is of great significance for conducting research on health monitoring systems for lifting equipment. On the other hand, the new structure proposed in this study matches the operating frequency in the shaft lifting system, and the energy harvest efficiency is higher.

Startup Analysis and Design of Self-Powered Auxiliary Power Supply in Input-Series System With Small Submodule Capacitance

Startup Analysis and Design of Self-Powered Auxiliary Power Supply in Input-Series System With Small Submodule Capacitance

A Dual-Frequency Modular Wireless Power Transfer System for Auxiliary Power Supply of Power Electronics Converters

A Dual-Frequency Modular Wireless Power Transfer System for Auxiliary Power Supply of Power Electronics Converters

Design, modeling, and validation of a 0.5 kWh flywheel energy storage system using magnetic levitation system

The flywheel energy storage system (FESS) has excellent power capacity and high conversion efficiency. It could be used as a mechanical battery in the uninterruptible power supply (UPS). The magnetic suspension technology is used in the FESS to reduce the standby loss and improve the power capacity. First, the whole system of the FESS with the magnetic levitation system is introduced, and the control diagrams of the charging/discharging processes are developed. Moreover, the force modeling of the magnetic levitation system, including the axial thrust-force permanent magnet bearing (PMB) and the active magnetic bearing (AMB), is conducted, and results indicate that the magnetic forces could stably levitate the flywheel (FW) rotor. The stator part and the FW rotor are analyzed using the FEM model, and the results could satisfy the requirements on stress and strength of the FESS at the rated speed. Then, the control models are established to accomplish the rapid charging/discharging functions of the FESS. Finally, experiments are performed to test the charging/discharging ability, and the results show that an excellent control current could enhance the charging/discharging efficiency so the stable DC link voltage could be outputted at the discharge process. Therefore, the test results prove that the designed FESS could be used as an auxiliary power supply for the UPS when the grid power fails.

An online comprehensive health monitoring system for automotive auxiliary converter

Abstract As an essential part of the electronic system in electric vehicles (EVs), the automotive auxiliary converter (AAC) connects the batteries and burdens the auxiliary power supply. This paper mainly proposes an online comprehensive health monitoring system for AAC. Firstly, based on the control diagram of the LLC resonant converter, three critical components are emerging, including capacitor, optocoupler, and semiconductor. These components can partly reflect the operation condition of the output loop, feedback loop, and control link, respectively. Then the characteristics parameters of these three components, equivalent series resistance (ESR) of the capacitor, current transfer ratio (CTR) of the optocoupler, and on-resistance of the semiconductor jointly construct the three-dimensional health monitoring vector. Finally, the online monitoring accuracy is verified and the proposed system can thus effectively promote the operation and maintenance of AAC. Furthermore, the online health monitoring system enables a flexible expansion, which can be further customized into different kinds of power converters, showing high applicability and practicality.

Simple Encapsulation Method for Flexible Perovskite Solar Cells with Transparent Electrode‐Integrated Barrier Films

Flexible perovskite solar cells (PSCs) have been rapidly developed for realistic applications such as windows and auxiliary power supplies of electronics. However, the moisture penetration through the flexible substrate films still poses a major obstacle because it can destroy the perovskite films under outdoor conditions. Unlike conventional PSCs with glass‐based encapsulation, flexible PSCs face challenges in finding suitable materials and structures that maintain flexibility while providing effective encapsulation. Simple encapsulation methods for flexible PSCs are proposed using a transparent electrode‐integrated flexible barrier (TIFB) substrate comprising silicon nitride (SiNx)/polyethylene terephthalate (PET)/indium tin oxide (ITO). A dense SiNx layer with chemical vapor deposition on ITO–PET films is deposited and a more flexible TIFB than the conventional laminated substrate owing to its thinness is achieved. TIFB shows a low water vapor transmission rate of 4.3 × 10−3 g m−2 day. Consequently, the efficiency of TIFB‐based PSCs under harsh conditions (60 °C and 90RH%) exhibits an acceptable decrease within 10% of its highest efficiency after 400 h, which is the most stable data under high temperature and humidity among existing flexible encapsulated PSCs. TIFB, as a flexible substrate, is a major candidate to protect flexible electronics and PSCs against external factors.

ПРИСТРОЇ КОРИГУВАННЯ ФОРМИ НАПРУГИ МЕРЕЖІ, ЯКА ЖИВИТЬ НАПІВПРОВІДНИКОВИЙ КЕРОВАНИЙ ВЕНТИЛЬНИЙ ВИПРЯМЛЯЧ ЗІСТАВНОЇ З МЕРЕЖЕЮ ПОТУЖНОСТІ

The paper investigates the application of a technical method of volt-addition in converters designed to correct the voltage waveform of the network supplying a powerful controlled valve rectifier of comparable power to the supply network. A modification of the circuit of a known converter with a diode rectifier adapted for the case of supplying a controlled rectifier and for correcting the voltage waveform at its input is considered, and its shortcomings are indicated. The original effective circuit and technical solutions of devices for correcting the shape of the mains voltage using the method of volt-addition are presented. In the first solution, the device is powered from the auxiliary power supply, and in the second, more universal, it is powered directly from the mains transformer. Ref. 7, fig. 3.

Research on energy management strategy of aviation high-power battery auxiliary power supply system

Research on energy management strategy of aviation high-power battery auxiliary power supply system

Design of 3-level LLC converter voltage controller for wide input voltage fluctuations

The auxiliary power supply unit for railway vehicles delivers various power to the passenger car. Maintaining isolation between the catenary power line and the auxiliary power in the compartment is typically essential. To ensure electrical isolation, an efficient LLC resonant converter is utilized among isolated DC-DC converters. Generally, LLC resonant converter primarily employ PFM control method. However, there is a limitation in increasing the switching frequency at high input voltages, making it difficult to handle wide input voltage fluctuations from the overhead catenary power line. To overcome this limitation, the PFM control method is introduced alongside the existing PFM control method, resulting in the presence of two controllers. However, since these two controllers regulate the output voltage differently, there is a potential for output voltage overshoot due to significant input voltage fluctuations. This paper proposes a method that combines PFM and PWM controllers, along with feed-forward compensation, to address these issues. The effectiveness of this proposed method is validated through PSIM simulation and experimentation.

A Power Self-Balanced High Step-Down Medium Voltage DC Converter With Expandable Soft-Switching Range

This paper proposed a power self-balanced high step-down medium voltage dc converter with expandable soft-switching range. The proposed one features the input voltage self-balance of each submodule and the current self-balance of each MOSFET, due to the sub-modules transmitting the same power through LC-coupled branches. The LC-coupled branch provides multiple direct AC power paths from medium voltage input to load, eliminating the losses caused by conventional multi-stage transmission. Each submodule of the proposed converter is a soft-switching unit that uses an auxiliary inductor to achieve soft switching, which reduces the resonant current and facilitates the expansion of the number of modules, without redesigning the transformer, instead of the conventional resonant converter that reduces the transformer magnetizing inductance to achieve soft-switching. Moreover, an auxiliary power supply scheme for the proposed converter is provided, which is used to solve the problem of difficult startup of the medium voltage DC converter, where the negative impedance characteristics of the series-connected auxiliary power supply are suppressed without the need for lossy voltage sharing resistors. A prototype with 1kV dc input and 100V/1kW output is built to verify the feasibility of the proposed topology.

Assessment of the TEROS 10 and TEROS 12 sensors in soil moisture measurement

This study focuses on investigating the accuracy of the empirical equations proposed by the manufacturing company for the widely used TEROS 10 and TEROS 12 sensors. Specifically, the study examines whether the raw - unprocessed - measurements provided by the two sensors lead to reliable predictions of soil moisture and electrical conductivity values when these particular empirical equations are utilized. For this purpose, a prototype setup was developed, incorporating a lowcost microcontroller along with auxiliary power supply and data acquisition circuits for the sensors. The results highlight the need for specific calibration of the sensors for each soil type and salinity level. Additionally, the behaviour of the sensors operating at low frequency (70 MHz) under increasing salinity conditions is contrary to expectations.

A Scalable Self-Powered Balancing Circuit for High-Step-Down-Ratio Auxiliary Power Supply

A Scalable Self-Powered Balancing Circuit for High-Step-Down-Ratio Auxiliary Power Supply

Research on electrical automation devices under embedded real-time operating system design

Abstract As the scale of the electrical system becomes more and more large and the structure becomes more and more complex, the performance of the electrical automation device is therefore required to be higher. This paper studies the electrical system automation device, and from the perspective of universality, designs and establishes the hardware platform of the electrical system automation device composed of six plug-ins, such as human-machine interface, auxiliary switch input, AC input, communication, power supply, and central processor. On this basis, μC/OS-II is adopted as the embedded real-time operating system of this paper to develop and design the software of the electrical system automation device. Then, the principle of the protection device for embedded system electrical automation is analyzed, and a microcomputer line protection device based on the full-circle Fuchs algorithm is proposed. The empirical analysis of the embedded system electrical automation device shows that the maximum system task response time is 145 μs and the minimum is 10 μs, which are all no more than 1 ms. When testing including the single board state, the keyboard, the alphabetical mode, the basic function, and the single board line module sending and receiving, the pass rate of all the testing items is more than 99%, which verifies that this paper is based on the embedded real-time operating system of the feasibility and effectiveness of the electrical automation device.

CM Noise Modeling and Reduction for Multi-output Dual-switch Flyback Auxiliary Power Supplies

CM Noise Modeling and Reduction for Multi-output Dual-switch Flyback Auxiliary Power Supplies

Medium Voltage Auxiliary Power Supply using Forward Converter integrated with Switched Capacitor Cells

Medium Voltage Auxiliary Power Supply using Forward Converter integrated with Switched Capacitor Cells

Design of High-power Density and High-frequency Transformers for Auxiliary Power Supply System in Electric Multiple Units

Design of High-power Density and High-frequency Transformers for Auxiliary Power Supply System in Electric Multiple Units

Fault-tolerant single-input dual-output converter with preserved output under fault operation

DC-DC converters have played an important role in the auxiliary power supply to electric vehicles, DC micro-grids, and portable electronic applications. To reduce the number of components and to improve the power density, multiport DC-DC converters have been recently proposed. Many multi-output converters are designed based on specific operational constraints on duty ratio or inductor currents. Further, simultaneous control of outputs is critical and involves cross-regulation issues. This paper proposes a single-input dual-output (SIDO) DC-DC converter with fault-tolerant circuit configuration to circumvent these challenges. The designed converter is helpful for the simultaneous control of loads by cross-regulation issues and has simple control without any control constraints on duty ratio or inductor currents. The topology proposed in this paper, can most significantly tolerate the failure during open-circuit for single and multiple switches and gives the preserved output voltage under fault case. The effectiveness and feasibility of the proposed configuration is validated using MATLAB/Simulink.

High Frequency Current-Fed Isolated Auxiliary Power Supply for Medium-Voltage Converter

High Frequency Current-Fed Isolated Auxiliary Power Supply for Medium-Voltage Converter

An Intelligent Controller Based on Extension Theory for Batteries Charging and Discharging Control

The main purpose of this paper is to develop an intelligent controller for the DC-link voltage of bidirectional soft-switching converters used in the batteries with equalizing charge and discharge control. To accelerate the equalizing charge and discharge speed of batteries, the DC-link voltage controller of the bidirectional converters is designed based on extension theory. Firstly, the photovoltaic module arrays (PVMAs) are used with the intelligent maximum power point tracker (MPPT) for supplying the power to the load side. Through the bidirectional soft-switching converters, the PVMAs will be allowed to carry out the uniform charging and discharging for the storage battery in order to achieve the intended energy storage and auxiliary power supply functions. In terms of the controller design, the quantitative design techniques are utilized, by which the P-I controller parameters will be designed for the converter when attempting to achieve the same control performance at different working points. As a next step, the aforesaid parameters are used together with the extenics theory. Based on the variation in the output power of the bidirectional converter and that in the voltage of the storage battery, it allows the system to find out the intended P-I controller parameters that will be approximate to the prescribed control performance when operating under different working conditions. As a result, the P-I controller will be provided with more efficient control flexibility and control performances. Finally, actual test results demonstrated that the response time of the proposed intelligent extension controller is shortened by 3% compared to the quantitative design of the proportional–integral (P-I) controller. Based on the proposed quantitative design of an intelligent controller for uniform charging and discharging management of batteries, the sustainable utilization of renewable sources of energy can be improved. At the same time, the better economic benefit of the energy preservation system is obtained. In addition, it also prolongs the life cycle of batteries, and then enhances the reliability of the batteries.