1 introduction
The exchange frequency conversion velocity modulation
technology is the modern electric drive technology important
development direction, along with the electric power electronic
technology, the micro electron technology and the modern control
theory in the exchange velocity modulation system application, the
frequency conversion exchange velocity modulation has gradually
substituted for the past slippery difference velocity modulation,
变极 velocity modulation, velocity modulation system and so on
direct current velocity modulation, more and more widespread
application to industrial production and daily life many domains.
But because receives the use environment, in the service life as
well as artificial operation some factors, the frequency changer
service life greatly for reduces, simultaneously also appeared various
breakdown in the use. Under we and everybody make a discussion
on frequency changer some common breakdowns and the countermeasure.
2 frequency changers static test result diagnoses
First we may make a static to the frequency changer the
test, the common general frequency changer approximately includes
following several parts (1) the levelling circuit; (2) direct
current intermediate circuit; (3) inverts the electric circuit;
(4) control circuit. The static test mainly is to the
levelling circuit, the direct current intermediate circuit and the
contravariant electric circuit partial high efficiency transistor
(power module) a test, the tool mainly is an avonmeter. The
levelling circuit mainly is to a rectification diode pro and con to
the test judges its quality, certainly we also may use the pressure
resistance table to test. The direct current intermediate
circuit mainly is to the filter electric capacity capacity and the
pressure resistance survey, we also may observe on the electric
capacity the safety valve whether does explode start, whether or not
leaks the fluid phenomenon and so on to judge its quality The
power module quality judgement mainly is to in the power module after
flow diode judgement. Do we also have to judge whether regarding
the IGBT module in have the trigger voltage in the situation to lead
pass and shut off.
3 is at through frequency changer demonstration
diagnosis
(1) OC. Crosses the electric current
breakdown
This possibly was inside the frequency changer the most
common breakdown. We first must fix the breakdown which causes
as a result of the parametric problem. For example the electric
current limit, the rise time excessively short all has the possibility
to cause the electric current production. Then we must judge
whether the electric current examination electric circuit did have the
problem. Take FVR075G7S-4EX as the example: We sometimes
can see FVR075G7S-4EX also cannot have the electric current
demonstration in the receiving a telegram machine movement time
kneading board. Does the electric current come from to where?
By now had to test its 3 Hall sensor, for determined that sensor
damage, we may every time open a sensor time opens time machine,
looked whether can have has flowed the demonstration, after passes
through experiments the basic performance to fix the OC breakdown like
this.
(2) OV. 过电?breakdown
We first must fix the breakdown which causes as a result
of the parametric problem. For example decelerates the time
excessively to be short, as well as has pressed and so on which causes
as a result of the regeneration load, then we may look whether the
输入?voltage does have the question, finally we may look whether
the voltage examination electric circuit did appear the breakdown, the
general voltage examines the electric circuit the voltage sampling
spot, all is the middle direct current return route voltage. We
take three are willing SVF303 as the example, after it (about 530V
direct current) falls the direct current return route sample after a
resistance number bigger resistance presses carries on the isolation
again by the light pair, when the voltage surpasses a definite value,
demonstrated "5" have pressed (this machine for digital tube to
demonstrate) we may look whether the resistance does oxidize changes
the value, whether the light pair does have short-circuits the
phenomenon and so on.
(3) UV. Owes the voltage
We first may look whether the 输入?voltage does
have the question, then looked the voltage examination electric
circuit, the breakdown judgement and has pressed same.
(4) FU. Fast fuse breakdown
In the frequency changer which present promotes mostly
has promoted the quick melt failure detection function.
(Specially is high efficiency frequency changer) take the
LG030IH-4 frequency changer as the example. It mainly is the
behind voltage carries on the sampling examination to the quick melt
front, when quickly will melt the damage later inevitably to be able
to appear quickly melts a terminal voltage not to have, this time will
isolate the light pair movement, will appear FU to report to the
police. Replaces the quick melt on because this to be able to
solve the problem. Specially should pay attention is in replaces
before the quick melt to have to judge the host return route whether
has the question.
(5) OH. Crosses the heat
Mainly causes the reason frequency changer interior to
radiate is not good. We may inspect the radiation ventilator and
ventilate the channel.
(6) SC. Short-circuits the breakdown
We may examine the frequency changer interior whether
has short-circuits the phenomenon. We take settle Sichuan
616G5A45P5 as the example, we examine the internal line, possibly not
necessarily has short-circuits the phenomenon, this time we were
allowed to examine the power module to have the possibility to appear
the breakdown, in actuated in the electric circuit normal situation,
the replacement power module, should be able to repair the machine.
4 concluding remark
Frequency changer breakdown many and varied, we only can
unceasingly summarize in the practice, try to find out a set of fast
effective processing frequency changers breakdown the means.
Above only is myself in a practice dessert, discusses together
with everybody |
