【正文】 tware to read in this module the fixes the entire module on the corresponding radiator. Thus it can be seen. The modular goal not only lies in the easy to operate, but reduces the entire machine volume. Cancels the traditional segment more the parasitic parameter to the electric stress which withstands the ponent falls to lowest. Moreover, high efficiency switching power supply, because the ponent capacity limit and the increase redundancy enhance the reliable aspect the many independent modules unit parallel work generally. Uses flows the technology. All modules share the load current together. Once some module expiration other modules equally share the load current again. Thus, not only enhanced the power capacity，Has satisfied the big electric current output request in the limited ponent capacity situation， Moreover said the power very small redundant power source module through the increase relatively overall system. Enormous enhances the system reliability. Even if 11，000 appears the single module breakdown. Also cannot affect the system the normal provides the full time for the repair in traditional power electronic technology. The control section is designs and the work according to the simulated signal. In six,7039。s，The electric power electronic technology is pletely the establishment in the analogous circuit foundation. But, now the digital signal， the digital circuit appear more and more importantly. The digital signal processing technology consummates day by day maturely. Demonstrates more and more many advantageous for the puter processing control，avoids the simulated signal the distortion distorting， reduces the stray signal the disturbance, is advantageous for the software package debugging and the remote sensing regulating. Also is advantageous for from the diagnosis， faulttolerant and so on technical implanting. Therefore，in eight， 9039。s，Said regarding each kind of electric circuit and the system design. The simulation technology is useful. Specially, Such as the print making butut， electromagnetic patibility (EMC) the question as well as the power factor revises (PFC) and so on the question solution. It can not leave the simulation technology the knowledge. But regarding intellectualized switching power supply. Need to use the puter to control the time. The digitized technology could not leave. The electrical power system green has two meanings. First is the remarkable electricity saving， This meant generating capacity economy. But generates electricity is causes the environmental pollution the important reason. Therefore the electricity saving may reduce to the environment pollution. Next these power sources cannot (or are few) have the pollution to the electrical network. The international electrician mittee (IEC) has formulated a series of standards regarding， IEC917， IECl000 and so on. In fact，many powers electrons electricity saving equipment. Often it can turn to the electrical network source of pours into the serious higher harmonic current to the electrical network, causes the total output factor to drop, result of the electrical network voltage coupling many burrs peaks. Even appears lacks the angle and the distortion in 20 century39。s ends. Each kind of active filter and active pensator plan births. These were the 2l century volume production each kind of green switching power supply product has laid the foundation.Above this example showed in amplifies in the process， the people simulate the sound signal with the voltage signal，between this kind of physical quantity is maintaining the proportional relationship in the certain scope. The electronic circuit which the simulation electronic technology is the research which with material and so on silicon， germanium makes the electronic device poses，to changes the signal to carry on application the continuously and so on control， processing science and technology. Electronic technology according to processing signal different way， May divide into the simulation electronic technology and the numeral electronic technology. If in the electronic circuit the signal is changes continuously， then belongs to the analogous circuit。 If in the electronic circuit the signal has the sudden change， the pulse like， Then belongs to the digital circuit. These two kind of electric circuits difference lies in the electric circuit neutron ponent working mode active status not to be dissimilar， latter daytoday work in switch condition, is when passes the time interval， First work in linear variation condition. The power switch in some design adopts a high frequency power conversion circuit using DCDC converter, which controls the energy flow by controlling the time ratio of switch and shutdown, and thus produces highquality adjustable DC output voltage. The switch has two major systems: the main control circuit and loop control circuit the main control circuit is the main AC transformer circuit which passes rectifier filter to the loading circuit, and the control loop circuit is a circuit which controls the work statue of the main control circuit according to the input and output conditions of PWM waveform generated by UC3843. The present day power supplies use a capacitive input filter when powered from the AC power line. A resulting shorting is that the AC line is rectified which results in high peak currents at the crests of the AC voltage as shown in Figure 13. These peak currents are typically three to five times higher than the average current drawn by the power supply. This causes excessive voltage drop in the wiring and imbalance problems in the three phase delivery system. Also the full energy potential of the AC line is not utilized.A popular method of acplishing this is by using a boost converter prior to the actual power supply. Boostmode supplies exhibit the largest input dynamic range of all the switching power supply topologies. Input voltages down to 30 volts can be boosted to 370 volts on its output (high