High Power Supply Research Articles

A High Energy Density Pulsed Power Supply for Micro Electrical Discharge Machining of High Aspect Ratio Holes

Abstract In micro-electrical discharge machining (EDM), it is difficult to guarantee machining efficiency and accuracy when further increasing the aspect ratio of microholes due to poor circulation of working fluid and removal of debris. In order to increase the ratio of material vaporization erosion and reduce the ejection of large debris caused by material melting, this study proposes a high energy density pulsed power supply that increases the peak discharge current by adding energy-storage inductors with designed charging and discharging control. Machining microholes of diameters from 100 μm to 200 μm with aspect ratios of 10:1, 20:1, and 30:1 show that when the inductance increases from 4.7 μH to 20 μH, the peak current increases by more than two times and the machining efficiency improves by approximately 30%, and the accuracy of the aperture consistency is enhanced, while the occurrence of microcracks on the machined surface is significantly reduced.

Numerical simulation of condensation heat transfer characteristics of R134a at high vapor velocity under different angles

Heat pipe is widely used as an efficient built-in heat exchanger for thermal management of high pulse and heat flux power supplies. Enhanced heat dissipation at the condensing side is an important issue in heat pipe research, where vapor velocity is an essential factor affecting the condensing heat transfer characteristics. This study adopted the CFD method to numerically simulate the condensation heat transfer of R134a flowing in a smooth pipe. The flow condensation heat transfer characteristics, such as film thickness and heat transfer coefficient (HTC), were investigated under vapor velocities v = 20–100 m/s and tube inclinations β =-90–90° Geometric and numerical heat transfer modeling is established in high vapor velocity flow condensation. The error of numerical simulation results and model validation is 10%. The HTC increases rapidly with the change in vapor velocity under 60 m/s, increasing the rate to 0.4. When the vapor velocity exceeds 60 m/s, the growth trend slows to 0.15, 37.5% of the original increase. At high vapor velocities above 60 m/s, the effect of pipe inclination on condensation heat transfer coefficient can be almost negligible. A modified empirical correlation suitable for high vapor velocities is proposed, which has higher predictive accuracy when the vapor velocity exceeds 80 m/s.

A low temperature coefficient wide temperature range bandgap reference with high power supply rejection

This paper presents a low temperature coefficient and wide temperature range bandgap reference with high power supply rejection. High temperature curvature compensation of this circuit is accomplished by MOSFET transistors operating in the subthreshold region. With the proposed piecewise compensation technique, the temperature range is extended. At the same time, a pre-regulator structure is adopted to improve the line sensitivity and suppress the ripple of the power supply. The novel bandgap reference is proposed and verified in 180nm CMOS process. The measured is 1.18V at 3.3V power supply voltage, and the static current of the circuit is 75uA. Over the wide temperature range of -60∼160◦C, the temperature coefficient achieves 5.72ppm/◦C, and the power supply rejection is -93.26dB at low frequency.

Experimental studies on the role of thermoelectric module structure in developing a powerful miniature power generator with a meso-scale opposed flow porous combustor

At present, the rapid development of miniaturized electronic devices relies on energy sources with long endurance and high power density, leading to the demand for the comprehensive performance of combustion based micro-thermoelectric systems such as high power supply and high power density. In this study, a meso-scale opposed flow porous combustor was designed and an experimental platform for thermoelectric systems with observable flames was built with different thermoelectric modules. The influence of the thermoelectric module structure on the characteristics of the thermoelectric system is studied, which is based on experiments. An evaluation method based on λ is proposed to analyze the matching of thermoelectric modules with different system performance. The results show that the λ has a different non-linear relationship with the optimal load, output voltage and output current. The maximum output power (9.8 W), system efficiency (4.13 %), power density (0.17 W/cm3), and the conversion efficiency of thermoelectric module (6.12 %) are obtained by experiments. Compared with previous studies, the thermoelectric system in this study has outstanding comprehensive performance, which provides a guidance for the optimization of the thermoelectric system. At the same time, the results provide that the evaluation method has the ability to quickly identify the thermoelectric module and the suitable solution for the cold and heat source.

An Intelligent Glove of Synergistically Enhanced ZnO/PAN-Based Piezoelectric Sensors for Diversified Human–Machine Interaction Applications

Human–machine interaction is now deeply integrated into our daily lives. However, the rigidity and high-power supply of traditional devices limit their further development. Herein, a high-performance flexible piezoelectric sensor (HFPS) based on a novel zinc oxide/polyacrylonitrile/Ecoflex (ZnO/PAN/Ecoflex) composite membrane is proposed. Due to the synergistic piezoelectricity of ZnO and PAN, the output voltage/current of the HFPS is increased by 140%/100% compared to the pure Zno/Ecoflex composite membrane. Furthermore, the fabricated HFPSs also have excellent sensitivity, linearity, stability and flexibility under periodic pressure. On this basis, due to its flexibility, stretchability and battery-free characteristics, a self-powered HFPS-based intelligent glove is proposed to wirelessly control diverse electronic systems through human hand gestures. In the meanwhile, the intelligent glove has been successfully applied to car two-dimensional motion, light bulb control and fan control. With the advantages of simple operation, portability and low power consumption, the glove is expected to provide new application prospects for human–machine interaction systems.

Research and Application on High Quality Power Supply Technology of New Distribution System

Under the dual-carbon target, the intermittent grid-connection of high-permeability distributed power generation and random charging of large-scale electric vehicles increase the volatility and randomness of the distribution network. Meanwhile, the coupling correlation between the power network, information network and social network will be significantly enhanced. In view of the highly uncertain operation of the new distribution system, under the existing distribution network operation control and operation and maintenance management system, This paper puts forward the realization mode of high quality power supply for the new distribution system from three aspects: the adaptability of the grid, the overall perception ability and the improvement of the operation control ability.

Design of High-Precision Infrared Photoelectric Sensor and Its Adoption in Soft Package Counting Management in Workshop

As an imperative part of information technology, photoelectric information technology is widely applied in smart phones, mobile computers, portable electronic products, medical care, and industrial technology. In this research, a high-precision infrared photoelectric sensor is designed, which utilizes XDU3093 chip as a built-in photoelectric sensor. The chip has the characteristics of high-power supply rejection ratio and temperature compensation. Then, the focus is on the design of infrared driving module and infrared detection module. Among them, the pulse current of the infrared drive module is more than 100 mA, and the output current is in the form of square wave. To control noise, an isolation circuit between the infrared drive and other modules is set. Infrared detection involves photoelectric sensor. The nwell diode in CMOS process is utilized as photosensitive diode, and at the same time, the surface of the diode is coated to ensure that only infrared light can generate photocurrent through coating. In the experiment, the infrared driver is simulated, and the results show that the driver module can effectively amplify the collected infrared signals, and the detection accuracy reaches 0.2 V. The simulation of infrared detection suggests that there is a linear relationship between photocurrent and background infrared illumination, and the photocurrent decreases with the increase of distance. The designed infrared photoelectric sensor is applied in the soft package counting link of workshop management. The infrared photoelectric acquisition signal is converted into an analog voltage signal, which is processed by the voltage conversion circuit and then transferred to the single chip microcomputer and software module. After the data is uploaded to the upper computer through the serial port, it shows that the number of soft packages can be accurately identified in the workshop soft package counting link based on the designed infrared photoelectric sensor.

Design of a downhole high-power voltage-regulated power supply system for logging-while-drilling systems based on PWM

Design of a downhole high-power voltage-regulated power supply system for logging-while-drilling systems based on PWM

A Multipurpose and Power Quality Improved Electric Vessels Charging Station for the Seaports

To avoid air and noise pollution on seaports, the use of electric vessels and shore-to-ship power supply based charging station on seaports are in trend, which is also known as cold ironing (CI) infrastructure. In the starting stage, electric vessels charging stations are being implemented on the most busiest commercial ports, where modern electronic devices are used to serve different types of vessels. These devices only take care of the quality of output power. However, on the input side, it creates a serious harmonic issue. During CI, megawatt range of power is supplied to the ships, so generated harmonics and interharmonics in the high-power supply based charging system become more dangerous for the grid. In this article, we propose a novel power quality improved cold ironing (PQICI) system (charging mechanism) to overcome this issue. Moreover, due to inherent multipurpose useability, this novel PQICI is able to supply different types of power to various types of vessels, such as ac power, dc power, 50 Hz frequency, 60 Hz frequency, single phase, three phases, three-wire network, four-wire network, five-wire network, and different ac and dc voltages. Furthermore, this PQICI supply system is capable of serving four vessels at a time. In every type of loading condition with different kinds of power supply mode, the PQICI maintains the power quality on the input side, with fulfilling the varieties of the power demand of vessels. The capability of the developed “PQICI” system is tested for different types of ships and vessels on the simulation platform as well as through real-time hardware-in-the-loop experimentation. On IEEE standard 519, satisfactory test results on both platforms show the efficiency of the developed system and its control mechanism.

Research on the Design of UAV Relay Charging High-rise Platform for Electrical Equipment Live Detection in Substation

The multi-rotor UAV inspection technology has received extensive attention in the live detection of electrical equipment in substations and has begun to be practically applied. However, due to the short endurance and the characteristics of intermittent operations, the UAV needs to frequently travel between the operational airspace and the cabin, which seriously affects the operational efficiency of the inspection. This paper first introduces the traditional substation electrical equipment live detection technology and then summarizes the application of UAV inspection in the substation electrical equipment live detection. Finally, in view of the shortcomings of the existing technology, this paper proposes a design scheme of a relay-charging high-rise platform for live detection and inspection of electrical equipment in substations. The relay charging high-rise platform can be divided into six parts according to the functional structure: high-altitude apron, UAV landing guidance system, UAV automatic binding system, high insulation strength power supply system, and platform monitoring system. In this paper, the overall structure of the relay charging high-level platform and the technical solutions of each component are described in detail. The technical solution can effectively improve the efficiency and safety of multi-rotor UAV inspection operations for live detection of electrical equipment in substations.

Optimal Design Method of High Voltage DC Power Supply EMI Filter Considering Source Impedance of Motor Controller for Electric Vehicle

Passive filters are often used for electromagnetic interference (EMI) suppression on the high voltage (HV) DC side of motor drive systems due to their simple structure and large noise suppression. However, the traditional passive filter design method takes less consideration of the change of the system source impedance, which will lead to almost no insertion loss in some frequency bands or an over-design of the filter. Based on the onboard working conditions of high-voltage and high-current, this article adopts the dual current probe method to obtain the source impedance of the system when it is working, and proposes a filter multi-objective optimization design method based on the genetic algorithm (GA). This method automatically selects the optimal topology of the filter and related component parameters according to the source impedance and load impedance, avoiding the filter resonance phenomenon and over-design problems caused by not considering source impedance. The experimental results show that conducted interference voltage and current of motor drive system with filter designed by the proposed method can pass CISPR25-2016rd level 3.

Development of the management system of technical indications of high-power charger-discharger rectifier device

Uninterruptible power supply devices are the main sources of operational DC power supply to control devices and control devices. In addition, the charge-discharge rectifier devices in thermal power plants and substations are autonomous operational current sources of power plants and substations. This source is the main constant and alternating current source for relay protection devices, telecommunication devices, control and monitoring devices in power stations and substations. As switching devices, the most commonly used ones today are thyristor, controlled by the thyristor control electrode. It is possible to control the charging and discharging processes of the batteries. In this case, random charging or discharging of the battery will reduce its service life. Therefore, this article examines its management system. Today’s high-power uninterruptible power supply rectifier devices show that stations and substations are not ready for emergency situations due to their unstable operation and inability to control the state of the battery. Therefore, the improvement of this device remains the major issue.

Digital control unit for switching power supplies based on STM32G474RET6 microcontroller

The article is devoted to the development of a digital control unit based on a specialized STM32G474RET6 microcontroller, which will improve the software algorithm for controlling a switching power supply. The developed block consists of a minimum number of components and is a universal basis for controlling high-power power supplies with complex topologies. The microcontroller program makes efficient use of the computational resources of the new hardware. Illustr.: 4. Table: 1. Bibliography: 10 titles.
 Keywords: block, source, impulse, microcontroller, control.

Design Of High-Speed Low Voltage Operational Amplifier

Background: The Operational amplifier (op-amp) is the building block of linear integrated electronics, therefore proposing newer design models with improved parameters is an essential landmark in the electronics industry in the hunt for a faster and more efficient design. Objective: To attain high speed and low power supply, the authors designed an op-amp using three different techniques. Initially compensating network was designed and simulated but the resultant output voltage saturates in inverting and non-inverting modes. Methods: Voltage feedback op-amp (VFOA) and current feedback op-amp (CFOA) were proposed to achieve the target. The authors have successfully designed the circuit, but the power dissipated is less and Common Mode Rejection Ratio (CMRR) is high in CFOA in comparison to VFOA. Results: The results are simulated for three different configurations and inverting configuration results in remarkable results in comparison to a non-inverting and differential amplifier. Inverting configuration using VFOA results in 91.22dB, and 0.0131W CMRR and power dissipation, respectively, while that of CFOA results in 97.34dB, and 0.0129W CMRR, and power dissipation, respectively. Conclusion: 1.6% improvement in CMRR and a 26.8% improvement in power dissipated for the proposed CMOS CFOA in comparison to the proposed VFOA. All the validations are done by plotting the bode plot and Nyquist plot.

Design and Development of High Voltage High Pulse Power Supply using FPGA for Dynamic Impedance Matching

High Voltage High Pulse Power Supply (HVHPPS) is designed with the goal to match fixed load, so thatprecise pulse output can be achieved. Generally the loads involve magnetron, klystron, and particle accelerators etc. The HVHPPS output pulse shape changes with load impedance variation due to various reasons. Due to changes in impedance, the performance of Pulse Power Supply degrades and reflects the power at the source end which causes component failure and system shut down. To overcome such problems, a scale down High Voltage High Pulse Power is designed and developed to match the dynamic impedance variations upto 25 % of mismatch. In earlier days, all HVHPPS were designed using microcontrollers where the problem of pulse to pulse monitoring and computational speed was compromised. The availability of variable and self-defined, Field Programmable Gate Array (FPGA) controller, which provided flexibility to design the pulse to pulse shaping and various vital parameter monitoring, made it possible. This paper presents the design and implementation of HVHPPS over an FPGA platform to meet the fast response requirement. This paper provides a solution for impedance mismatch problems associated with such types of power supply, and also presents specifications for major components in a high voltage pulse power system for various types of load ranges. An experimental test hardware was designed and developed for HVHPPS to implement dynamic impedance algorithm and validate the results.

High Bandwidth Series-Form Switch-Linear Hybrid Envelope Tracking Power Supply With Reduced Bandwidth Envelope and Step-Wave Edge Adjustment Methods

The series-form switch-linear hybrid envelope tracking (ET) power supply is constituted by a multilevel converter and a linear amplifier connected in series, featuring high efficiency and wide tracking bandwidth. With the development of wireless communication, the envelope bandwidth of the radio-frequency signal reaches tens of megahertz and even hundreds of megahertz, leading to a high switching loss in the multilevel converter and thus degraded overall efficiency of the ET power supply. To reduce the switching loss and ensure high tracking bandwidth, this article proposes to let the multilevel converter track the reduced bandwidth envelope signal and the linear amplifier track the original one. Then, a step-wave edge adjustment method is proposed to adjust or eliminate the rising and falling edges of the step-wave voltage for further reducing the equivalent switching frequency of the multilevel converter and the voltage across the power device of the linear amplifier. As a result, the switching loss in the multilevel converter and the power loss in the linear amplifier could be reduced, leading to a notably higher overall efficiency. A prototype with 40 MHz tracking bandwidth, 7–27 V output voltage, and 15 W average output power is fabricated and tested in the lab, and the experimental results are provided to verify the effectiveness of the proposed method.

Novel RDD Pulse Shaping Method for High-Power High-Voltage Pulse Current Power Supply in DBD Application

High-voltage pulse power supplies are key power input devices for the study and application of discharge plasma. A high-voltage pulse current power supply (HV-PCPS) with an energy storage pulse transformer based on flyback topology can output microsecond pulsewidths with high-power, ultrahigh voltage, and high reliability, which are suitable for most dielectric barrier discharge (DBD) plasma applications. However, during the process of DBD driven by an HV-PCPS based on an energy storage pulse transformer, the output pulse voltage waveform quality is poor, making it not suitable for stable discharge long-term operation. This article aims to solve the aforementioned problem and proposes a novel resistor–diode–diode (RDD) shaping method. Not only can this novel method solve the problem of poor quality of the output pulse power from the HV-PCPS, guaranteeing stable discharge for various DBD electrodes, it can also limit the maximum output voltage amplitude. This prevents overvoltage breakdown when the output terminal is in an open state or a light load state because the HV-PCPS is acting as a current source. This article also analyzes the effectiveness of an RDD branch when solving the problem in theory, and gives a detailed parameter design method. Finally, a 30-kV HV-PCPS prototype is built to verify the effectiveness of the proposed RDD pulse shaping method. The average pulse power output of the whole prototype is greatly improved, and it can achieve an average pulse power output of 1 kW. Furthermore, the electrode loads of different DBD reactors can be driven by this technology.

First-order Bandgap Reference Source Design with High Power Supply Rejection Ratio

In this paper, a first-order bandgap reference source with a high power supply rejection ratio (PSRR) is designed. To obtain a low-temperature coefficient, a first-order bandgap temperature coefficient compensation method is used by adjusting the resistor resistance of the positive and negative temperature coefficients, and the gate-source voltage of the current mirror transistor is kept constant to increase the PSRR value in the low-frequency band. A self-start circuit is added to make the circuit start up quickly out of the simple bias point. The simulation results show that the bandgap reference voltage source has a constant 1.25V reference voltage with a temperature coefficient of 8.55ppm/°C in the temperature range of -40 to 125°C. The circuit is simulated using Cadence software. The circuit can be applied to OLED constant current source circuits and power management circuits.

Integrate a high precision scan magnet power supply in NSRRC

This work describes the integration of a high precision power supply in a scan magnet in National Synchrotron Radiation Research Center (NSRRC). Horizontal and vertical energy transmission to the scan magnet are independent. The high precision and sinewave are utilised to produce a smooth circle field. This power supply has an air cooling system and a more protective function to keep the machine and magnet from being damaged. During the scan magnet application, the maximum current is 12.5 A, and the inductor is 30 mH at 20 Hz sine wave. Accordingly, Kecpo BOP 72-14 model with a maximum current of 14 A and maximum output voltage of 72 V is chosen. Finally, an integrated high-precision scan magnet power supply is created in the laboratory. Experimental result shows the output current ripple and bandwidth, with the output current being 14 A and the maximum ripple being 0.45 A. This combination is simple because no resistor is in parallel with the magnet coils. Lastly, this work demonstrates the magnetic field, output current ripple, and frequency variation with output current to prove that this power supply meets the requirements.

A Fast Transient Low-Dropout Regulator with High-Power Supply Rejection

With the continuous popularization of portable electronic products in electronic information, aerospace, biomedicine and other fields, low-dropout regulator (LDO) has become an important part of modern power management chips. Compared with other power management modules, it has the advantages of low power consumption, high power supply rejection, and strong anti-noise capability. However, the LDO power tube has a large width-to-length ratio, so when the load changes transiently, the gate of the power tube cannot respond in time, resulting in an overshoot and undershoot of the output voltage and a long recovery time. In this paper, the LDO transient enhancement circuit is designed. When the load changes transiently, the power tube gate capacitor is quickly charged and discharged, which overcomes the overshoot voltage and undershoot voltage. While improving the transient response of traditional LDO, the structure ensures the power supply rejection (PSR) and other performance of the circuit. According to the results, with an input of 2.5 V, the output voltage is regulated to 1.2 V, and PSR is -80 dB. When the load changes by 20 mA in 1 μs, it is stable within 1.2 μs while the undershoot voltage is controlled at 51 mV and the overshoot voltage is controlled at 65 mV.