SCM has been in ac speed regulating system had been used widely

SCM has been in ac speed regulating system had been used widely. For example by Intel company 1983 years development and

production of MCS - 96 series is the higher performance of the single chip microcomputer is one of the series, it is suitable

for high speed and high precision industrial control. The high-grade type: 8 x 196 KB, 8 x 196 kc, 8 x 196 MC in general open

loop ac speed regulating system of used more often.
Because ac motor control theory development, control strategy and control algorithm is also increasingly complex. Extended

kalman filtering, FFT, the state observer and adaptive control, artificial neural network and so on are applied to all kinds of

ac motor vector control and direct torque control of. Therefore, DSP
rotating joint in all digital high performance ac speed regulating

system find cast a stage. Such as TI company such as MCS320F240 DSP chip, with its high cost performance became full digital ac

adjustable speed system preferred. TI company recently launched MCS320F240X series of products will be more price down to the

level of the single chip microcomputer.
In ac speed regulation of full digital process, various bus also play a very important role. STD bus, industrial PC bus, field

bus and CAN bus in ac adjustable speed system automation application field play an important role.
3 PWM technology
PWM control is the control of ac adjustable speed system core, any control algorithm and the ultimate realization of almost all

kinds of rotary union PWM control mode is completed. Has been put forward and get the practical application of PWM control scheme is not more

than ten kinds, about PWM control technology based on the many famous electric power international conference, such as PESC,

IECON, EPE annual meeting has formed special. Especially microprocessor application in PWM technology and digital later, pattern

is unceasingly, from the pursuit of the voltage waveform sine, to the current waveform of sine, then to magnetic flux of sine;

From the optimal efficiency, torque ripple at least, to eliminate noise and so on, PWM control technology development has

experienced a constant innovation and improvement process. So far, there are new scheme continuously put forward, further proves

that this technology is in the ascendant.
Among them, the space vector PWM technology to the voltage utilization ratio is high, the control algorithm is simple, current

harmonic characteristics such as small in ac speed regulating system got more and more application.
4 high pressure large capacity ac speed regulation system
In the small power ac speed regulation, because foreign product scale effect, make domestic manufacturer in price, process and

technology are unable to fiber optic rotary joint fight. And in high voltage power, foreign companies and left us catch up space. First of all, foreign

power grid voltage level general for 3000 v, and China's power grid voltage class for 6000 v and 10000 v; Secondly, high

pressure high power ac speed regulating system can't large-scale batch production, and foreign labor cost, especially have

certain professional knowledge labor cost is higher.