Shenzhen can the industry limited company
superficial correspondence power source technology parameter
development
In the recent ten years, the development which
progresses by leaps and bounds along with the telecommunications,
correspond the power source to take the telecommunication network the
foundation, also have made the considerable progress. The high
frequency switching power supply involves the electron, the micro
electron, the sensor, the computer, the network and so on the many
kinds of technologies, is more and more widespread in the
telecommunication profession application. This article passes
the credit high frequency switching power supply from many sides brief
analysis our country the development, and makes a discussion to
several important technical specifications, tries to state its
standard request and the test method and so on.
First, passes the credit high frequency switching power supply
the development
1st, technological development
At the beginning of the 90's, control the power source
to occupy the dominant position, possibly very many people also to
that unwieldy rack, the gigantic labor frequency conversion depressor
have a vivid memory. The high frequency switching power supply
application has brought the brand-new meteorology for the
telecommunication construction, the advanced technology is the
important attribute which the high frequency switching power supply
can rapidly promote.
The high frequency switching power supply most early uses is the
pulse-duration modulation (P W M) the technology, its characteristic
is with 20 k H z pulse controlling switch converter, the efficiency
may reach 70%, the volume slightly, the weight is light, is opposite
to the linear power source, is in a technical big breakthrough.
Afterwards, the new high frequency power semiconductor device,
power M O S F E T and I G B T development causes the switching power
supply to the high frequency development, the turn-on frequency to be
possible to reach 300 - 400 k H z, thus obtains the higher power
density. But under the hard switch pattern, in the switch
process the voltage rise/drop and the electric current rise/drop
profile overlap has the loss, also advances along with the turn-on
frequency enlarges, thereupon the soft switch technology, the accurate
resonant technology research forms the hot spot, the center of gravity
is reduces this kind of profile overlapping, the realization zero
potential/zero current breaker. Our country has applied it to 6
k w passes in the credit high frequency switching power supply, the
efficiency reaches 93%.
Active power factor adjustment technology (A P F C) the
development, enhanced A C - D the C switching power supply power
factor, both governed electrical network overtone "to pollute", and
enhanced the switching power supply overall efficiency. Control
technology progress, if the electric current reaction control method,
enable the switching power supply dynamic performance to have the very
big enhancement. The new magnetism material and the new
transformer development, the new capacitor and E the M I filter
technology progress, the special-purpose integrated control chip
develops successfully, causes the switching power supply
miniaturization, and enhanced E M the C performance. The
microprocessor monitors the application, enhanced the power source
reliability, also adapted the market to its intellectualized request.
In brief, reviews the switching power supply technology history,
we may see, the high efficiency, the miniaturization, the integration,
the intellectualization, the redundant reliability are ultimately,
also will be the next development direction.
2nd, production development
In the correspondence power source domain, the national
industry always holds the pivotal status. In the switching power
supply application start stage, the very many productions factory
adopts all is the small workshop -like production pattern, passes
through more than ten years unremitting endeavors, gradually
transforms to the large scale production, the product also moves
towards the seriation from the sole variety. Now, China has
formed on one batch hundred million Yuan, even 1 billion Yuan above
output values power source enterprises, some products entered the
international market. In 1991 domestic correspondence power
source investment cost for Renminbi 080 million Yuan, increased to
1995 to 1 billion Yuan, to 199 Yuan, even 1 billion Yuan above output
values power source enterprises, some products entered the
international market. In 1991 domestic correspondence power
source investment cost for Renminbi 080 million Yuan, increased to
1995 to 1 billion Yuan, increased to 1998 to 3 billion Yuan, in 1999
the national correspondence power source market capacity is above 3.5
billion Yuan. Grows 43 times from 1991 to 1999, the development
speed is astonishing. The Chinese power source market
competition and the development result inevitably promotes the
industrial interior differentiation and the combination, superior win
and the inferior wash out, forms one batch of formidable enterprises
to lead the market. After joins W T O, the domestic market
internationalization, the next market competition will be the quality
competition, the technical competition, talented person's competition,
the service competition. The enterprise needs to persist the
high beginning, the high standard, surely cannot be eager for quick
success and immediate gain.
3rd, market development
The market demand is the power source industry
development formidable propelling force. At the beginning of the
90's, the correspondence domain starts when introduces the high
frequency switching power supply, only is 48 V/10 A, 48 V/20 A module
composition small system, 1,995, in 1996 entered a big development
time, the installed capacity 5 years expanded three, four times,
appeared 50, 100, 200 A module composition several thousand ampere big
systems. In 1999 the fixed net controls power source the
transformation approximately 6 - 800 million Yuan, newly built network
the and so on exchange, transmission necessary power source
approximately 5 - 700 million Yuan, this explained the program
controlled switch necessary power source market already tended to
steadily. The mobile communication follows closely is becoming
the development hot spot, in 1999 increased the mobile subscriber
compared to 1998 approximately 24 million, newly built motion 基站
24,000, the necessary power source approximately 2 billion Yuan, 2000
development step was approximately quicker. In the recent two
years, turned on the net the construction to attract the massive
investments, cut off to June 30, 2000, China access the net the user
to reach 16900000, access the net the computation scheme are 6.5
million, but the present far turns on the net facility not to meet the
need, turned on the net power source market the development potential
and the space is huge, slightly was not inferior to the mobile
communication power source the market.
4th, standard making
At the beginning of the 90's, the high frequency
switching power supply application just in the telecommunication
profession start, at the right moment promulgated "Passes Credit High
frequency Switch Rectifier" and "Passes the Post office (To stand)
Electrical power system Total Specification" and so on the standard to
instructs the production, the service user to play the vital role,
also got up for the high frequency switching power supply in the
telecommunication profession rapid promotion the positive role.
Along with the market expansion, the user is more and more high
to the power source intellectualization degree request, the related
correspondence power source centralism monitoring standard is promoted
one after another. Unceasingly progresses along with the
technology, the experience gradually accumulates, we deeply felt the
profession standard urgent need revision, the technical specification
needs to improve, the test method needs to consummate, the content
needs to increase, for example the dynamic response, electromagnetic
compatibility and so on, for provides the good product quality pass a
more reliable basis.
Second, to technical specification discussion
1st, static
Y D/T 731 - 94 "Passes Credit High frequency Switch
Rectifier" center to the static request quite comprehensive, including
Feng Feng value, width frequency, telephone 衡重 and separate
static, but as a result of are more with the static this terminology
close noun, if did not understand their corresponding relations, can
have the question. The Feng Feng value static is surveys with
the enough band width oscilloscope, is the profile is biggest and
difference of the minimum value. The wide frequency static is
uses in the bandpass filter interception certain band width the static
to obtain really 有效? The telephone weighted noise is
after the telephone weighting network wide frequency static, main
weight to telephone conversation voice quality influence. The
separate static is with chooses in the sole frequency peak-to-peak
value which the frequency decibel meter or the spectrum analyzer
obtains, an greater value appears much in on turn-on frequency
frequency multiplication. I E in the C standard proposed the
"cycle and stochastically drifts" (P A R D) a word, the definition
cycle part is a ripple, stochastic partial is the noise, the ripple
and the turn-on frequency harmony low low frequency band static
actually is through adjusts the return route but is not, voltage
regulation speed which the filter return route solves quick, the
tendency responds, the low frequency band static is small.
2nd, power factor and harmonic current
In order to reduce the city electrical noise the
influence which tests to the power source, when general test was
measured the power source all meets in purifies on the power source,
but we discovered has the power source meets when purifies on the
power source works, voltage degree of distortion, harmonic current
quite big, the power factor is small, when trades the city
electricity, the power factor actually enhances. In the
practical application, the high frequency switching power supply has
receives the diesel oil power set the situation, certainly not always
meets the city electricity, therefore has the necessity to analyze
this kind of phenomenon the origin, favor produces the factory
improvement. Looked from the surface that, was measured the
power source meets on the city electricity works normally, meets in
purifies on the power source not to be good, then, certainly was
purifies the power source to have the problem, actually otherwise, the
root or in was measured on the power source, the key was was measured
the power source worked when produced the harmonic current too was
big. City electricity internal resistance very small, absorption
harmonic current ability very strong, therefore has not created the
very great voltage distortion, power factor also quite high, but
purifies the power source 内阻 as well as the diesel oil power set
内阻 cannot ignore, they absorb the harmonic current the ability
limitedly, can create the great voltage distortion, the power factor
small, but if were measured the power source the power factor adjusts
partially does very much well, the power factor is very high, when
work produces the harmonic current cannot superhigh purify the power
source the absorbancy. Actual middle, through enhances the
diesel oil power set the capacity to enhance the absorption harmonic
current the ability to mean enlarges the cost, therefore basic
solution or the improvement switching power supply power compensating
circuit, reduces the harmonic current, reduces to the electrical
network pollution and the energy loss.
3rd, dynamic response
The dynamic response evaluates the switching power
supply stable important target, 超调?and restores the time to
receive the electric current step leap quantity, the electric current
rate of change and 允差 the belt influence, but in the profession
standard has only made the definition to the electric current step
leap quantity, causes in the practical application to be possible to
be operational is not strong. In the switching power supply
output circuit or in the test connection return route inevitably has
the certain inductance, but the electric current rate of change and
the inductance product will have the certain induced e m f.
Therefore, the electric current step leap certainly is not
ideal, always has the certain slope, if did not stipulate the electric
current rate of change, the measurement result lacks the
commeasurability. Generally takes the electric current rate of
change in the American industry standard is 2 A/mu s or 5 A/mu s.
Moreover, but also should unify the test method, if 突加
suddenly reduces with the air switch hand control load, the air switch
vibration time on already surpassed restored the time the request,
caused measurement result plate out of true, met uses may the
controlling current rate of change electronic switching pass breaks
the load.
Shenzhen can the industry limited company (direct current
screen, wall hanging power source) Zhong Nengrong all rights reserved,
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