scholarly journals Implementation and Control of an AC/DC/AC Converter for Double Wound Flywheel Application

2012 ◽  
Vol 2012 ◽  
pp. 1-8 ◽  
Author(s):  
J. G. Oliveira ◽  
H. Schettino ◽  
V. Gama ◽  
R. Carvalho ◽  
H. Bernhoff
Keyword(s):  
High Voltage ◽  
Low Voltage ◽  
Experimental Tests ◽  
Prototype System ◽  
Unity Power Factor ◽  
Good Efficiency ◽  
In Series ◽  
Vector Modulation ◽  
Acceleration Mode ◽  
And Control

An all-electric driveline based on a double wound flywheel, connected in series between main energy storage and a wheel motor, is presented. The flywheel works as a power buffer, allowing the battery to deliver optimized power. It also separates electrically the system in two sides, with the battery connected to the low voltage side and the wheel motor connected to the high voltage side. This paper presents the implementation and control of the AC/DC/AC converter, used to connect the flywheel high voltage windings to the wheel motor. The converter general operation and the adopted control strategy are discussed. The implementation of the AC/DC/AC converter has been described from a practical perspective. Results from experimental tests performed in the full-system prototype are presented. The prototype system is running with satisfactory stability during acceleration mode. Good efficiency and unity power factor could be achieved, based on vector control and space vector modulation.

scholarly journals A Novel Series Connected Batteries State of High Voltage Safety Monitor System for Electric Vehicle Application

2013 ◽  
Vol 2013 ◽  
pp. 1-12
Author(s):  
Qiang Jiaxi ◽  
Yang Lin ◽  
He Jianhui ◽  
Zhou Qisheng
Keyword(s):  
Electric Vehicle ◽  
High Voltage ◽  
Critical Issue ◽  
Monitor System ◽  
Equivalent Models ◽  
In Series ◽  
Remaining Capacity ◽  
Electric Parameters ◽  
Hardware In Loop ◽  
And Control

Batteries, as the main or assistant power source of EV (Electric Vehicle), are usually connected in series with high voltage to improve the drivability and energy efficiency. Today, more and more batteries are connected in series with high voltage, if there is any fault in high voltage system (HVS), the consequence is serious and dangerous. Therefore, it is necessary to monitor the electric parameters of HVS to ensure the high voltage safety and protect personal safety. In this study, a high voltage safety monitor system is developed to solve this critical issue. Four key electric parameters including precharge, contact resistance, insulation resistance, and remaining capacity are monitored and analyzed based on the equivalent models presented in this study. The high voltage safety controller which integrates the equivalent models and control strategy is developed. By the help of hardware-in-loop system, the equivalent models integrated in the high voltage safety controller are validated, and the online electric parameters monitor strategy is analyzed and discussed. The test results indicate that the high voltage safety monitor system designed in this paper is suitable for EV application.

A scalable strategy toward compliant tandem yarn-shaped supercapacitors with high voltage output

2021 ◽  
Author(s):  
Juan Zhang ◽  
Qingli Xu ◽  
Xiangyu Qian ◽  
Xinhou Wang ◽  
Kun Zhang
Keyword(s):  
High Voltage ◽  
Aqueous Electrolyte ◽  
Low Voltage ◽  
Voltage Output ◽  
In Series

Yarn-shaped supercapacitors (YSSCs) based on aqueous electrolyte exhibit relatively low voltage output due to the low decomposition voltage of water (~1.23 V). Applying organic-based electrolyte or connecting YSSCs in series...

The Research of Capacitive Load Influence on Inductive Voltage Divider

2013 ◽  
Vol 718-720 ◽  
pp. 1537-1541
Author(s):  
Yan Qiang Li ◽  
Wen Feng Li ◽  
Hai Ming Shao ◽  
Fei Peng Lin ◽  
Bo Liang ◽  
...  
Keyword(s):  
High Voltage ◽  
Voltage Dependence ◽  
Low Voltage ◽  
Analytical Formula ◽  
Voltage Divider ◽  
Model Analysis ◽  
Circuit Model ◽  
Capacitive Load ◽  
In Series ◽  
Inductive Voltage Divider

The inductive voltage divider is usually used and calibrated at no-load situation, but it also used at taking load situation. For example in the situation of measuring voltage dependence of low voltage capacitors and detecting high voltage bridge, the inductive voltage divider need to take two specific capacitors. This paper have researched the influence of specific capacitive load on its ratio and deduced the analytical formula through related experiments and circuit model analysis when it takes capacitor. And use the method of connecting resistor in series to compensate its ratio accuracy to 1×10-6 degree.

scholarly journals Cascade frequency converters control features

2020 ◽  
Vol 241 ◽  
pp. 37
Author(s):  
A. Vorontsov ◽  
V. Glushakov ◽  
M. Pronin ◽  
Yu. Sychev
Keyword(s):  
High Voltage ◽  
Single Phase ◽  
Power Converters ◽  
Low Voltage ◽  
Frequency Converter ◽  
Frequency Converters ◽  
Three Phase ◽  
In Series ◽  
Load Characteristics ◽  
Active Rectifiers

The structures of systems with high-voltage cascade frequency converters containing multi-winding transformers and low-voltage low-power converters connected in series at each output phase of the load are considered. Low-voltage blocks contain three-phase diode or active rectifiers, DC capacitor filters, single-phase stand-alone voltage inverters and block disconnecting devices in partial modes (in case of failure when part of the blocks are disconnected). The possibilities of operation of cascade converters are determined, equations for correcting tasks to units in partial modes are given, tables of correction of tasks with estimates of achievable load characteristics are proposed. The results of experiments on the model of a powerful installation with a cascade frequency converter are presented, confirming the possibility of ensuring the symmetry of the load currents when disconnecting part of the blocks and the asymmetry of the circuit.  

scholarly journals Hybrid Multilevel Converters: Topologies, Evolutions and Verifications

Energies ◽  
2019 ◽  
Vol 12 (4) ◽  
pp. 615 ◽  
Author(s):  
Jianzhong Zhang ◽  
Shuai Xu ◽  
Zakiud Din ◽  
Xing Hu
Keyword(s):  
High Voltage ◽  
Control Strategies ◽  
Multilevel Converter ◽  
Power Devices ◽  
Multilevel Converters ◽  
Voltage Balancing ◽  
In Series ◽  
Good Potential ◽  
And Control ◽  
Balancing Control

Multilevel converters have good potential in high power and high voltage applications due to their advantages of reduced voltage or current stress on power devices. In recent years, hybrid multilevel converter (HMC) have attracted increasing attention since less equipment is required. In this paper, the topologies and evolutions of HMCs are presented, where five topology derivation ways are given by using basic cells in series-parallel/parallel-series. Some general topologies or structures that are used to generate higher levels are also deducted. Then many existing HMCs can be derived, and new topologies of the HMC might be inspired. The capabilities of neutral point and FC voltage balancing control are investigated. The performance of the selected FC-based HMCs is analyzed. Finally, the verifications of operation principle and control strategies for the derived HMCs are carried out.

scholarly journals Design of High-Voltage Switch-Mode Power Amplifier Based on Digital-Controlled Hybrid Multilevel Converter

2016 ◽  
Vol 2016 ◽  
pp. 1-9
Author(s):  
Yanbin Hou ◽  
Wanrong Sun ◽  
Aifeng Ren ◽  
Shuming Liu
Keyword(s):  
High Voltage ◽  
Low Voltage ◽  
Prototype System ◽  
Maximum Output ◽  
Multilevel Converter ◽  
Peak Voltage ◽  
Class D Amplifier ◽  
Class D ◽  
Digital Pulse ◽  
Switch Mode

Compared with conventional Class-A, Class-B, and Class-AB amplifiers, Class-D amplifier, also known as switching amplifier, employs pulse width modulation (PWM) technology and solid-state switching devices, capable of achieving much higher efficiency. However, PWM-based switching amplifier is usually designed for low-voltage application, offering a maximum output voltage of several hundred Volts. Therefore, a step-up transformer is indispensably adopted in PWM-based Class-D amplifier to produce high-voltage output. In this paper, a switching amplifier without step-up transformer is developed based on digital pulse step modulation (PSM) and hybrid multilevel converter. Under the control of input signal, cascaded power converters with separate DC sources operate in PSM switch mode to directly generate high-voltage and high-power output. The relevant topological structure, operating principle, and design scheme are introduced. Finally, a prototype system is built, which can provide power up to 1400 Watts and peak voltage up to ±1700 Volts. And the performance, including efficiency, linearity, and distortion, is evaluated by experimental tests.

scholarly journals High Voltage, Low Current High-Power Multichannel LEDs LLC Driver by Stacking Single-Ended Rectifiers with Balancing Capacitors

Electronics ◽  
2020 ◽  
Vol 9 (3) ◽  
pp. 529
Author(s):  
Kang Hyun Yi
Keyword(s):  
High Voltage ◽  
High Power ◽  
Low Voltage ◽  
Driving Voltage ◽  
Led Driver ◽  
Leakage Inductance ◽  
Voltage Stress ◽  
Driver Circuit ◽  
In Series ◽  
The Difference

In this paper, a new LLC converter for series-connected, high-voltage LEDs is proposed. The proposed LLC converter consists of two stacked, single-ended rectifiers and one balancing capacitor, to compensate for the current deviation of two individual LED strings. The proposed LLC LED driver can use a diode with low voltage stress, even if the secondary LED is connected in series to have a high driving voltage. In addition, even if several series-connected LEDs are changed into two-stacked structures, the balancing capacitor can compensate for the current deviation of the two separated LEDs, as well as the difference in leakage inductance of the two stacked single-ended rectifiers. The balancing capacitor can be made equal to the voltage tolerance of the stacked, single-ended rectifier diodes. The proposed circuit can be easily extended to a series channel LED driver circuit, without increasing the voltage stress. To verify the characteristics and operation of the proposed LLC LED driver, a 260W high-power LED driver is implemented.

scholarly journals A high voltage direct current transmission system : natural and selective harmonic cancellation

2019 ◽  
Vol 10 (3) ◽  
pp. 1410
Author(s):  
Aziza Benaboud ◽  
Alfred Rufer
Keyword(s):  
High Voltage ◽  
Direct Current ◽  
High Efficiency ◽  
The Other ◽  
Unity Power Factor ◽  
High Voltage Direct Current ◽  
Voltage Quality ◽  
Current Transmission ◽  
In Series ◽  
Harmonic Cancellation

<p class="AbsKeyBibli"><span lang="EN-US">This study focused on the special High Voltage Direct Current technology. The context is given by combining two original solutions; the first solution, using a natural harmonic cancellation, consists to connect in series two classical frequency inverters which are coupled to the grid through a specific transformer connection.  On the other hand, the second solution is achieved by using three, five or more level converters in square wave modulation, in order to eliminate some selective harmonics by optimizing a switching angle. The simulation and experimental results indicate that the proposed High Voltage Direct Current transmission systems offer high efficiency, unity power factor and better current and voltage quality with fewer harmonic.</span></p>

scholarly journals A Current Monitor System in High-Voltage Applications in a Range from Picoamps to Microamps

Electronics ◽  
2021 ◽  
Vol 10 (2) ◽  
pp. 164
Author(s):  
Rabí Soto-Camacho ◽  
Sergio Vergara-Limon ◽  
María Aurora Diozcora Vargas-Treviño ◽  
Guy Paic ◽  
Jesús López-Gómez ◽  
...  
Keyword(s):  
High Voltage ◽  
Particle Physics ◽  
High Energy Physics ◽  
Low Voltage ◽  
High Energy ◽  
Electron Multiplier ◽  
Current Consumption ◽  
Constant Operation ◽  
Analog Part ◽  
In Series

In this article, we present a system to measure current in the range of 0 to 10 μA with high-voltage isolation up to 5 kV. This current monitor consists of three ammeters connected in series, to improve the resolution in the measurement. The design features several innovative elements such as using low voltage to provide power to the devices to measure the current and digitize it with a sampling frequency of 1 KHz, it is generated based on a DC-DC converter that produces three voltages, +12 V, −12 V, and 5 V, from a conventional 10 V source. The three voltages are referenced to the same floating ground. The DC-DC converter has a high voltage insulation up to 5 kV and four optocouplers with an insulation up to 20 kV are used to read the digitized data. The introduction of a DC-DC converter contributed to reduce the noise level in the analog part of the circuit which has been resolved implementing shields inside the board. In particle physics, several systems are used to detect particles in high-energy physics experiments such as Gas Electron Multiplier (GEM), micromegas, etc. GEMs suffer small deteriorations due to discharges in constant operation and require monitoring the current consumption at high frequency (1 kHz). In this work, we present the design and operation of a 0 to 10 μA auto scale ammeter. The results obtained by monitoring the current in a 10 × 10 cm2 GEM are shown.

Low-Voltage Variable Gain Current Amplifier for High-Voltage Signal Processing

2009 ◽  
Vol 129 (8) ◽  
pp. 1511-1517
Author(s):  
Nicodimus Retdian ◽  
Jieting Zhang ◽  
Takahide Sato ◽  
Shigetaka Takagi
Keyword(s):  
Signal Processing ◽  
High Voltage ◽  
Low Voltage ◽  
Current Amplifier ◽  
Variable Gain ◽  
Voltage Signal
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