Append magnetic field control on welding process is an advanced welding technology which is developing now. As plasma, welding arc has well electric character. Exterior magnetic field can affect shape and movement of welding arc. And the welding bead and drops transfer can also be changed to improve the welding process and advanced the productivity.Conventional magnetic field form used in weld...

With the discovery of new kind of Permangent-Manget material and development in manufacturing Permangent-Manget Synchronous Motor(PMSM),the PMSM control system have accepted more and more concerns. So, the research of PMSN control system must be a kind of inevitable development trend and the focus in the future, and it has great value and important meanings for Chinese researchers and the indu...

The most important performance requirement of table servo systems can be summarized as“high frequency response, super-low velocity, wide–velocity regulation and high accuracy”. Regarding to motor drive,“super-low velocity”is the guarantee of the smaller moment fluctuation with low velocity of the motor. However, as a result of the limitation of the manufacturing technological level, ...

Electroless nickel of low-phosphorous coatings have been widely applied in electronic fields because of its great solderability. Therefore, the study of electroless nickel plating technics of low-phosphorous is of great practical significance and value.In this paper, lactic acid and propionic acid system , citric acid and acetic acid, succinic acid and malic acid system which are the complexi...

The main function of transport package is to guarantee the safety of the product during transportation process and make the product get to the destination safely.But transport package is suffering from drop、shock、vibration and so on inevitably during circulation process.And drop impact is the main cause of damage,so it is necessary to quest the damage state of transport package caused by ...

In the field of AC machines control, a strategy called variable frequency control is mostly used. As a high performance and new machines control strategy developed in 1980\\\’s, direct torque control solves the problems that computation in vector transformation control is complex, the control characters are easily affected by the changes in machines parameters, real results of the experi...

With the further application of advanced technology in the welding field, the research of digital technology and wave controlled technology in new welding machine have been exploited two mainstream directions. In this paper, the control system of the power source for CO_2 short circuiting transfer is researched which is based on the technology of STT (the Surface tension transformation) and DS...

Two-degree-of-freedom gas-electric servo turntable is a kind of experimental instrument used in fixing projector array in laboratory, it can take performance test of some instruments under laboratory circumstance together with three-cylinder hydraulic turntable. The motion of gas-electric servo turntable is controlled by stepping motor and pneumatic. Based on analysis of the characteristics o...

At present,there are two puzzles for human beings,one is scanty of energy sources,the other is environment pollution.It is extremely important to economize energy sources before new ones are developed.High voltage multilevel inverters have the following advantages :high realiability,high input power factor,high efficiency,low cost,low input

Two main kinds of routes of replacing copper plating with cyanides, electrocoppering in acid solution and Pollution-Free electroless copper plating were explained in this thesis. The characteristics and limits in applying of electrocoppering in acid solution were introduced simply. The definition, characteristics and categories of Pollution-Free electroless copper plating and the pace of prog...