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Multilevel DC/AC Inverters have various structures. They have many advantages. Unfortunately, most existing inverters content too many components (independent/floating batteries/sources, diodes, Capacitors and switches). The author introduces the "Laddered Multilevel DC/AC Inverters” in this paper that...

Traditional methods of AC/AC converters have general drawbacks: output voltage is lower than input voltage, the input side THD is poor and output voltage frequency is lower than input voltage frequency by using voltage regulation method and cycloconverters. We introduce the novel approach - DC-modulated...

Regarding the AC UPS fault accident happened in one compressor station which caused severe consequence with gas transmission pipeline, this paper lists the possible reasons based on the recorded fault code and equipment configuration, and solutions are proposed for modification. In the end, recommendations...

In recent years, with the rapid development of micro electromechanical systems, low-power sensor networks and integrated circuit technology, the power supply problems are becoming the barrier of environment protection in practical and industrial. Vibration is a widely used energy in the environment,...

This paper introduces the design idea and realization method of AC constant current source, which is composed of direct digital synthesizer and digital potentiometer. The design has advantages of simple structure, strong practicability, high stability and high precision, and equipped with a standard...

A facile method to control the synthesis of zinc glycinate is described. Zn(Ac)2 and ZnO are used as zinc source, and H+ is used as catalyst. The composition and structure of the chelate compounds are characterized by infrared spectroscopy(IR), thermogravimetric analysis(TGA) and x-ray powder diffraction(XRD)....

Cohesion and coherence are essential elements that have a role in forming structural coherence and coherence of the meaning of discourse texts. The formation of a coherent structure and semantic relationship cannot be separated from using the correct elements of cohesion and coherence, which are marked...

This article illustrates the characteristics and proportion of GIS system failure through the introduction to GIS system structure and characteristics; In order to make the GIS in the safe operation of the power system, It is necessary to test AC withstand voltage at the scene.

the situation is grim for domestic civil electrical fire and arc fault is the main cause of electrical fires. Low-voltage arc fault protection technology in China is still in infancy, and has not yet established a complete low-voltage arc fault database and the arc fault protection system is not perfect...

The analysis and research inductive AC circuit characteristics for guidingthe use of inductive load equipment has practical significance. By combining experimental electrical theory to explain inductive AC circuit voltage and current relationships, power, influence electrical shunt capacitance of the...

To study the shearing performance of asphalt mixture with Lucobit, AC-13C and SUP-20 asphalt mixture with Lucobit were carried out the uniaxial penetration test and the the direct shear test. The results show that the angle of internal friction of the same gradation and temperature has little difference,...

The design for the normal operation of load in a period of time when the electricity suddenly interrupted. The whole design used "AC-DC-AC" form. The direct current can be obtained by the electricity after the rectifier or the battery voltage after boosting and then sent out after boosting and inverter....

To solve the problem of harmonic level evaluation for AC arc-furnace supply area, this paper analyses the synchronous measuring data of harmonic current in AC arc-furnaces with functional analysis, verifies harmonic current released from AC arc-furnaces with independence and orthogonality approximately...

This control of nonholonomic under actuated systems is an important field in nonlinear control. This thesis uses the example of an acrobat to illustrate the intelligent control of such systems. The acrobat is a two-link manipulator operating in a vertical plane. It consists of one joint each at the shoulder...

Cohesion and crack opening displacement based on cohesive zone model were employed to evaluate the fracture resistance of asphalt mixture of SMA-13 AC-13 and CAM at 10 5 0 -5 -10 . Using fracture toughness, cohesion and crack opening displacement index to analyze the crack resistance property of three...

Bending strain density threshold based on elastic damage theory, the j-integral based on elastic plastic fracture mechanics and Cohesion and crack opening displacement based on cohesive zone model were employed to evaluate the fracture resistance of asphalt mixture of SMA-13 AC-13 and CAM in the temperature...

Analyze the application of resonant voltage withstand test in the XLPE cable voltage withstand test, and the two methods of variable frequency resonant voltage withstand test were compared by an example. By comparison, the resonant voltage test method can effectively simulate the field voltage withstand...

This article describes the design process of a three-phase AC soft-switching static power supply using discrete pulse modulation (DPM) technology. Firstly, the principle diagram of the static power supply of the combined inverter structure is given. The working principle of the main circuit of the soft-switching...

Reference is deixis following the context of the language so that it always changes and appears in various situations and language events, resulting in the meaning of the reference in one lingual unit being different. This study examines the form of person and time deixis and their forms of reference...

In this paper design of LED lighting system based on AC (alternating current) bus power supply mode with low and variable frequency is proposed. Mainframe output alternating current with 250V effective value and 200Hz low frequency by conversion after APFC rectification. Extension set adopting capacitor...

The effect of quenching condition such as air cooled (AC) and water quenched (WQ) treatment on the corrosion behavior of 6063 Al alloy was investigated by optical microscope, field emission scanning electron microscope and electrochemical work station. The experimental results showed that the corrosion...

A novel sample treatment, namely vortex-assisted dispersive liquid-liquid microextraction (VDLLME), followed by GC/MS has been developed for the determination of gaseous phase polycyclic aromatic hydrocarbons (PAHs) emitted from a marine diesel engine. The method integrates extraction, enrichment, and...

Manipulator is the traditional task executing agency in industrial robot system, as well as one of the key components of the robot. The mechanical structure of the manipulator consists of ball screw, slider and other mechanical devices; electric aspect consists of AC motor, inverter, sensor and other...

Magnetic levitation (no bearings) motor by using magnetic force to make rotor suspend and drive realize its high or ultra high speed rotating. The stator’s structure of traditional no bearing magnetic levitation motor is double winding which is polar logarithmic difference 1 of 2 sets of winding (torque...

For joint photographic experts group (JPEG) steganography, which kinds of JPEG coefficients, i.e., the block discrete cosine transform (BDCT) coefficients that have been divided by the quantization steps and have been rounded, should be selected for data hiding is still an open problem. In this paper,...

The high voltage source of electrocurtain requirements for high power factor, high efficiency, output DC high voltage of low ripple, fast fault response. In order to improve the parameters to design a high voltage source which based on three-phase buck type PWM AC chopper. It has advantages of simple...

Dynamic response slow and DC voltage fluctuation when traditional current inner loop controller based on dq transformation applications in three-phase PWM voltage source rectifier (VSR). To these shortcomings, firstly this paper established discrete mathematical model of VSR, derived deadbeat control...

The paper study object is the CNC servo system, and it presented three closed-loops control strategy based on PMSM. Through dynamic mathematical model of current loop, rotational speed loop and position loop were established and simplified. The closed-loop regulator was designed. The system was corrected...

In recent years, in view of existing air conditioning system energy saving diagnosis research has been closely watched. As a typical air conditioning system energy saving diagnosis method, the observation/ac - test/computing - judgment/solution ""(the OTI) method is widely used in the practical project...

Based on working Principle of the direct-drive wind power system’s grid-connected inverter was research, the mathematical model for inverter in Three-phase rotating coordinate was established and analyzed. A double-loop control strategy that based on feed forward decoupling were introduced, Meanwhile,...

Make the composite electrolyte by doping Al2O3 powders ,in the ratios of 1:0.02 and 1:0.04 respectively to the electrolyte masses, into initial powders of the electrolyte-BaZrCeYO made in the method of Pechini. After 10 hours sintered at 1400 , the composite electrolyte was completed , XRD test carried...

Nowadays, with the development of the EHV grid and area of megacity, such as Shanghai, Nanjing. There are many factories and AC-DC converter substations are involved into the urban region, which causes much more power quality problems than before, so that more and more people focused on the power supply...

As the second generation of FACTS products, static synchronous compensator (STATCOM) can dynamically compensate for the reactive power of the system, thereby improving the operating characteristics of the system. The STATCOM is connected to the HVDC inverter AC bus, and the HVDC transmission system model...

To research the performance of asphalt mixture with lucobit. Firstly, research the rutting resistance mechanism of Lucobit,through the results of influence rule of aggregate and asphalt for modifier and the modification mechanism of modifier show that Lucobit modifier improves the pavement performance...

Proposed a solution on existing mobile communication network system solutions and validated. Verification test of the gateway device construction show that IPSec gateway support IPSec functions, support IPSec VPN users access multiple functions; support IPSec different access VPN users can access different...

Some new heterogeneous catalysts used to synthesize the tributyl citrate (TBC) and aspirin were prepared and characterized by brunauer-emmett-teller (BET), field emission scanning electron microscope (FE-SEM) and X-ray diffraction (XRD). The effect of temperature, catalyst loading and the concentration...

With the development of society, the energy and environmental problems have emerged, and restricts the development of traditional large power grid. In such a situation, it is particularly important for the rational use of new and renewable energy, so the power supply form of distributed generation has...

The present paper is aimed at introducing the author’s newly developed decision-making method, known as”intelligent decision-making method for The electric car filling in power station Planning and Management”. As we often see, it is a fundamental method to overcome the difficulties brought by great...

In order to solve the position control problem of AC servo system, a new control strategy for the position based on sliding mode control and predictive control is proposed. The sliding mode control law is deduced, and according to the dynamic matrix theory, predictive model, controller and corrector...

Electrical equipment is composed of the basic components of the power system, and its performance has a direct impact on the safety and reliable operation of the system, whether it is large equipment such as generators, transformers, or small equipment such as power capacitors, insulators, etc, if equipment...

With parameter values chosen to obtain good calculate, the experimental results show that the load will receive the maximum voltage and maximum electric power at resonant frequent 22kHz when Tesla coils are 4mm away. The maximum electric power transfered by two Tesla coils of diameter 30mm with 13 loops...

The dynamic characteristics of the rotary axis feed system has influence on the contour error. This paper presents a mathematical model of rotary table drive system of the CNC machine tool by using of mechanical dynamics. The model includes the simulation model of AC servo motor and the rotary table...

Most of radar apparatus equipped from the 1980s to the early part of this century were mainly manual and hydraulic leveling which were time-consuming and of low leveling precision. Thus, to avoid these problems, this paper attempts to design a leveling mechanism, which is driven by AC servo motor and...

Design a new photovoltaic grid connection device based on Freescale MK60FN1M0 processor and Multi-mode wireless communication technology. In terms of Modbus protocol, MK60FN1M0 communicates with photovoltaic inverter, the device acquires measurement data such as: DC voltage, DC current, AC voltage, AC...

The push-pull power boost and full-bridge inverter levels change in the control circuit, the first-stage booster circuit using SG3525 chip push-pull control, closed loop feedback; inverter part EG8010 complete SPWM modulation driver chip IR2110 be full-bridge inverter; after level output is sampled using...

In this paper, a theoretically efficient method is developed for face recognition. It is based on two dimensional principal component (2DPCA) analysis and extended local binary pattern (Extended LBP, ELBP) texture. First, the ELBP operator is employed to extract the local texture of the face images....

With the characteristic which the control of the multiphase machine is more complex compared with three-phase ac machine, a novel control method is proposed in this paper, namely six-phase motor trapezoidal wave phase current control. By using the trapezoidal phase current waveform, the stator winding...

Microgrid protection is one of the crucial technology of microgrid. In this paper, a new microgrid protection scheme was proposed, which is suitable for microgrid working in both grid-connected and island modes. We proposed a solution for the challenging problem in AC microgrid, as the limitation for...

The technology of network traffic detection is very important in the area of network managing, network monitoring and network security. The network traffics are sharply increasing along with the growing of the Internet. Because of the hardware limitation, the traditional traffic detection method can...

AC algorithm, as a multi-pattern matching algorithm, plays an important role in the intrusion detection system. The efficiency of the pattern matching algorithm directly affects the overall efficiency of the intrusion detection system. But the number of the growing intrusion features and demanding for...