Application of a Current and Voltage Mixed Control Mode for the New Fast Control Power Supply at EAST

A feedback control system is needed to restrain plasma vertical displacement in EAST （Experimental Advanced Superconducting Toknmak）. A fast control power supply excites active feedback coils, which produces a magnetic field to control the plasma＇s displacement. With the development of EAST, new demands on the new fast control power supply have led to an enhanced ability of fast response and output current, as well as a new control mode. The structure of cascaded and paralleled H-bridges can meet the demand of extended capacity, and digital control can reMize current and voltage mixed control mode. The validity of the proposed scheme is confirmed by experiments.

Programmable Voltage Regulating Method for 15 kV High Voltage DC Power Supply

In order to solve the disadvantages caused by mechanical slide rheostat that has big errors and low precision,a novel voltage regulation method for high voltage DC power supply was introduced.The key of this method were digital potentiometer MAXIM 5455 and linear photoelectric coupling LOC110,and application programs were compiled using Visual Basic which was graphical compiling language,furthermore the communication between exterior and computer was carried out by ICP7044D module,in consequence the output value of high voltage DC power supply could be regulated with computer.The measured results showed that this method could accurately,conveniently and rapidly regulate the output value of high voltage DC power supply.

Research on Voltage Losses of AT Traction Power Supply System

Unilateral power supply system has been used because of the management status of the power grid system, while, bilateral power supply system is adopted in the Soviet Union and France. The feasibility that whether bilateral system can be put applied in China is discussed. Compared with unilateral power supply system, bilateral system has better reliability and better capability of supply power system, which gives bilateral system more advantages over unilateral system on both engineering investment and operating efficiency. In this paper, voltage losses under the two different systems are calculated and also compared, the advantages of bilateral system is explored and then conclusion is drawn by referring to the practical data of passenger transport lines.

Experiment and Operation of a LHCD-35kV/2.8MW/1000s High-Voltage Power Supply on HT-7 Tokamak

A -35 kV/2.8 MW/1000s high-voltage power supply (HVPS) for HT-7 superconducting tokamak has been built successfully. The HVPS is scheduled to run on a 2.45 GHz/1 MW lower hybrid current drive (LHCD) [1] system of HT-7 superconducting tokamak before the set-up of HT-7 superconducting tokamak in 2003. The HVPS has a series of advantages such as good steady and dynamic response, logical computer program controlling the HVPS without any fault, operational panel and experimental board for data acquisition, which both are grounded distinctively in a normative way to protect the main body of HVPS along with its attached equipments from dangers. Electric power cables and other control cables are disposed reasonably, to prevent signals from magnetic interference and ensure the precision of signal transfer.This paper involves the experiment and operation of a 35 kV/2.8 MW/1000s HVPS [2] for 2.45 GHz/1 MW LHCD system. The reliability and feasibility of the HVPS has been demonstrated in comparison with experimental results of original design and simulation data.

6-28 Design of Portable-multifunctional PMT High Voltage Power Supply

In 2015, a 14-PIN photomultiplier tube (PMT) high voltage power supply was designed. This product consists of high voltage power supply, small signal processing and high voltage monitoring modules. The utility model adopts 3.75 V DC power input, tiny size, low power-consumption and good portability, extremely well meeting the requirements of the power supply for the PMT in the mobile station with a car battery.

Charging System of ECRH High-Voltage Power Supply and its Control System

High-voltage power supply (HVPS) of Electron Cyclotron Resonance Heating (ECRH) for HT-7 and HT-7U is presently being constructed. The high voltage (100 kV) energy of HVPS is stored in the capacitor banks, and they can power one or two gyrotrons. All the operation of the charging system will be done by the control system, where the field signals are interfaced to programmable logic controller (PLC). The use of PLC not only simplifies the control system, but also enhances the reliability. The software written by using configuration software installed in the master computer allows for remote and multiple operator control, and the status and data information is also remotely available.

Application of High-Voltage Power Supply on Electrostatic Precipitator

This article firstly describes the main technical parameters and performance of the high power supply of electrostatic precipitator, and then describes the structure, principle and characteristic of power supply of electrostatic precipitator, and finally analyses the common faults of power supply of electrostatic precipitator in the operation and puts forward the methods of dealing with breakdown. Operation results show that the system is stable and reliable, and overall performance and the efficiency of dust control have been improved significantly. The scheme has been well applied in the field of environmental protection and dust removal.

Design and Simulation of a Electrorheological(ER) Control High Voltage Power Supply

Few applications with electrorheological （ER） fluids have been found in industry. One reason is high voltage power supplies cannot meet the requirement for ER effect. In this paper, an ER control high voltage power supply for engineering application was designed which reduced power wastage by adopting soft switch technology; lessened its volume to satisfy micromation when adopting the planar transformer and improved its response character- istic by choosing an assistant discharging circuit. Simultaneously, a simulation analysis has been carried out. As results, the output voltage of this high voltage power supply is 5 kV, and the voltage can be continuously regulated and the voltage ripple is only 0. 7 %, so the requirement of stability is also achieved.

Electrical characteristics of new three-phase traction power supply system for rail transit

A novel three-phase traction power supply system is proposed to eliminate the adverse effects caused by electric phase separation in catenary and accomplish a unifying manner of traction power supply for rail transit.With the application of two-stage three-phase continuous power supply structure,the electrical characteristics exhibit new features differing from the existing traction system.In this work,the principle for voltage levels determining two-stage network is dissected in accordance with the requirements of traction network and electric locomotive.The equivalent model of three-phase traction system is built for deducing the formula of current distribution and voltage losses.Based on the chain network model of the traction network,a simulation model is established to analyze the electrical characteristics such as traction current distribution,voltage losses,system equivalent impedance,voltage distribution,voltage unbalance and regenerative energy utilization.In a few words,quite a lot traction current of about 99%is undertaken by long-section cable network.The proportion of system voltage losses is small attributed to the two-stage three-phase power supply structure,and the voltage unbal-ance caused by impedance asymmetry of traction network is less than 1‰.In addition,the utilization rate of regenerative energy for locomotive achieves a significant promotion of over 97%.

Optical fiber-based power and data delivery system for high voltage electronic current transformer

This paper describes a prototype power delivery system developed for high voltage electronic current transformer （ECT） that uses laser light to transfer power to and communicates with the primary converter. The design is based on optical-to-electrical power converters, solid-state diode lasers and optical fibers. Command signals are transmitted via the same up-fiber used to send power from secondary power supply to primary converter. The upward data transmission is completed during the brief interruption of power delivery without affecting steady power-supply. A simple comparator added to the primary converter can take the command data. Experimental results show that the fibers can provide reliable up-link for data transmission at 200 kb/s from the secondary to the primary converter. Based on the delivery system, the secondary converter can control three auxiliary channels to provide additional information. These monitoring channels are used in a time-multiplexing mode to provide information about the operation temperature, voltage and current at the remote unit for monitoring the ECT. This preventive maintenance or built-in test can increase reliability by giving early warning for necessary maintenance request.

High-PSRR High-Order Curvature-Compensated CMOS Bandgap Voltage Reference

A high-PSRR high-order curvature-compensated CMOS bandgap voltage reference( BGR),which has the performances of high power supply rejection ratio( PSRR) and low temperature coefficient,is designed in SMIC 0. 18 μm CMOS process. Compared to the conventional curvature-compensated BGR which adopted a piecewise-linear current,the temperature characterize of the proposed BGR is effectively improved by adopting two kinds of current including a piecewise-linear current and a current proportional 1. 5 party to the absolute temperature T. By adopting a low dropout( LDO) regulator whose output voltage is the operating supply voltage of the proposed BGR core circuit instead of power supply voltage VDD,the proposed BGR with LDO regulator achieves a well PSRR performance than the BGR without LDO regulator. Simulation results show that the proposed BGR with LDO regulator achieves a temperature coefficient of 2. 1 × 10-6/ ℃ with a 1. 8 V power supply voltage and a line regulation of 4. 9 μV / V at 27 ℃. The proposed BGR with LDO regulator at 10 Hz,100 Hz,1 k Hz,10 k Hz and 100 k Hz have the PSRR of- 106. 388,- 106. 388,- 106. 38,- 105. 93 and-88. 67 d B respectively.

Design and control of the accelerator grid power supply-conversion system applied to CFETR N-NBI prototype

The acceleration grid power supply(AGPS)rated 200 kV/25 A is a key component devoted to supply the acceleration grids of the China fusion engineering test reactor negative-ion-based neutral beam injector(N-NBI)prototype system.This paper focused on the design and control of the AGPS conversion system(AGPS-CS),with emphasis on the requirement of the wide range output voltage and rise time.A voltage regulation switch at the front of step-down transformer is applied to optimize the grid current and DC-link voltage.Moreover,a new feedforward control strategy with piecewise PI compensator is proposed to improve the characteristics of AGPS.The simulation results of the proposed AGPS-CS are presented,proving the performance of the power supply to achieve the desired requirements.

Design of a New Intelligent Anti-voltage Sag Control Module for AC Contactors

智能抗电压跌落交流接触器多使用在连续生产的企业中，不允许意外断电，针对这一特点，设计一款新型智能抗电压跌落控制模块，具有交流供电模式和控制模块直流可控供电模式。当控制模块正常时，通过控制模块给交流接触器线圈供电，具有直流无声运行、抗电压跌落等功能；一旦控制模块自身发生严重故障，起动转换电路，切断控制模块，通过有触点开关直接提供交流电给交流接触器线圈，维持生产系统正常工作，同时发出报警信号，在系统正常停机的情况下更换控制模块。详细分析了该智能控制模块的工作原理，尤其对开关电源的设计及有触点开关与无触点开关构成的转换电路进行分析，并进行仿真与实验研究。仿真和实验结果验证了所提方法的有效性。

The Design of PSM-Based ECRH Power Supply Control System

Electron cyclotron resonance heating (ECRH) system is one of the most important Tokamak auxiliary heating methods. However, there are growing demands for ECRH system as the physical experiments progress which meanwhile adds the difficulty of designing and building the control system of its power source. In this paper, the method of designing a control system based on Single Chip Microcomputer (SCM) and Field Programmable Gate Array (FPGA) is introduced according to its main requirements. The experimental results show that the control system in this paper achieves the conversion of different working modes, gets exact timing, and realizes the failure protection in 10us thus can be used in the ECRH system.

Detailed Analysis of the Transient Voltage in a JT-60SA PF Coil Circuit

A superconducting coil system is actually complicated by the distributed parameters, e.g. the distributed mutual inductance among turns and the distributed capacitance between adjacent conductors. In this paper, such a complicated system was modeled with a reasonably simplified circuit network with lumped parameters. Then, a detailed circuit analysis was conducted to evaluate the possible voltage transient in the coil circuit. As a result, an appropriate （minimum） snubber capacitance for the Switching Network Unit, which is a fast high voltage generation circuit in JT-60SA, was obtained.

Scheme of long distance power supply for electrified railway traction network based on traction cable

Purpose–The traction cable is paralleled with the existing traction network of electrified railway through transverse connecting line to form the scheme of long distance power supply for the traction network.This paper aims to study the scheme composition and power supply distance(PSD)of the scheme.Design/methodology/approach–Based on the structure of parallel traction network(referred to as“cable traction network(CTN)”),the power supply modes(PSMs)are divided into cableþdirect PSM and cableþautotransformer(AT)PSM(including Japanese mode,French mode and new mode).Taking cableþJapanese AT PSM as an example,the scheme of long distance power supply for CTN under the PSMs of co-phase and out-of-phase power supply are designed.On the basis of establishing the equivalent circuit model and the chain circuit model of CTN,taking the train working voltage as the constraint condition,and based on the power flow calculation of multiple train loads,the calculation formula and process for determining the PSD of CTN are given.The impedance and PSD of CTN under the cableþAT PSM are simulated and analyzed,and a certain line is taken as an example to compare the scheme design.Findings–Results show that the equivalent impedance of CTN under the cableþAT PSM is smaller,and the PSD is about 2.5 times of that under the AT PSM,which can effectively increase the PSD and the flexibility of external power supply location.Originality/value–The research content can effectively improve the PSD of traction power supply system and has important reference value for the engineering application of the scheme.

A New Buck-Based Configuration AC Chopper Voltage Conditioner

This paper presents a new AC chopper voltage conditioner, which can generate high quality sinusoidal waveforms with adjustable amplitudes. The circuit structure, operation principle, and control mode are analyzed in detail, the system essentially consisting of an equal duty cycle modulation AC voltage buck chopper and a voltage polarity change H-bridge, a full-wave rectifier, to perform tightly closed-loop control of the AC chopper voltage condtioner, a digital controller on a new converter model has been developed. The controller has very well dynamic response. To evaluate the new circuit and proposed control scheme, a 5kW conditioner is developed and the experimental results demonstrate that the system has good performances.

A Study on the Conducted Interference of Capacitor Charging Power Supply

In this paper, a mathematical analysis of the EMI (Electromagnetic Interference) for a 20 kHz/10 kV capacitor charging power supply in frequency-domain is presented, and a related circuit model considering the transient switching interference is proposed. Due to the high working frequency and the device-switching transitions, the conducted EMI caused by the charging circuit which includes the harmonics of grid frequency, working frequency and device-switching transition frequencies. Thus under certain working situations or loads parallel power supply, the interference may cause charging failure. To solve this problem, a high frequency transformer modeled with stray capacitances and an approximation of the device-switching transition is applied in the Spice-based simulation model, and a mathematical analysis in frequency-domain is presented.

A Novel Half-Bridge Power Supply for High Speed Drilling Electrical Discharge Machining

High Speed Drilling Electrical Discharge Machining (HSDEDM) uses controlled electric sparks to erode the metal in a work-piece. Through the years, HSDEDM process has widely been used in high speed drilling and in manufacturing large aspect ratio holes for hard-to-machine material. The power supplies of HSDEDM providing high power applica-tions can have different topologies. In this paper, a novel Pulsed-Width-Modulated (PWM) half-bridge HSDEDM power supply that achieves Zero-Voltage-Switching (ZVS) for switches and Zero-Current-Switching (ZCS) for the dis-charge gap has been developed. This power supply has excellent features that include minimal component count and inherent protection under short circuit conditions. This topology has an energy conservation feature and removes the need for output bulk capacitors and resistances. Energy used in the erosion process will be controlled by the switched IGBTs in the half-bridge network and be transferred to the gap between the tool and work-piece. The relative tool wear and machining speed of our proposed topology have been compared with that of a normal power supply with current limiting resistances.

Design of Power Supply for On-line Monitoring System of Transmission Lines

This paper uses CT to gain the energy directly from the high-voltage transmission line, to address the problem of power supply for monitoring system in high voltage side of transmission line. The draw-out power coil can induce voltage from the transmission line, using single-chip microcomputer to analog and output PMW wave to control the charging module, provides a stable 3.4 V DC voltage to the load, and solve the problem of easy saturating of core. The power supply based on this kind of draw-out power coil has undergone the overall testing, and it is verified-showing that it can properly work in a non-saturated status within the current range of 50 - 1000 A, and provide a stable output. The equipment also design protection circuit to improve the reliability to avid the impacts of the impulse current or short-circuit current. It effectively solves the problem of power supply for On-line Monitoring System of Transmission.