PV industry has come winter , the various
manufacturers of photovoltaic industry chain struggled desperately to cut costs
in order to be more ruthless price customers will be required , as the PV
inverter industry chain most technical content of days Jiaozi - PV
grid-connected inverter , also spared , 500KW grid inverter price, from today's
0.5 yuan per watt in 2009 dropped to 2.0 yuan per watt inverter manufacturers
in lower profits at the same time , alternative photovoltaic inverter also more
expensive components or even cancel conducted to ensure that the whole of the
price drop.
However, due to the special status of PVinverters in photovoltaic power plants , some inverter manufacturers cost
reduction measures have seriously jeopardized the entire industry. Because in
photovoltaic power plants , the cost of the inverter is less than 10 % loss
accounts for more than 80 % to 90% power generation efficiency of photovoltaic
power plants controlled by the inverter, inverter assessment methods can not
rely on the price , the more important the inverter is to look at the actual
generation capacity.
Now the domestic production of inverters up
to 300 manufacturers , ultimately left 10 influential manufacturers will come
home in the end what companies will ultimately survive , which companies will
be the first out , I think: just keep going back to the product quality route,
sense of social responsibility , moral bottom line, companies have continued to
improve capacity is the ultimate winner. I engaged in photovoltaic inverter
design more than five years , from the perspective of a systems engineer , to
tell you some bad Revealed manufacturers reduce costs insider.
MPPT efficiency mystery , in the
photovoltaic inverter specifications book, most manufacturers have MPPT
efficiency of this indicator, some marked as 99% , some even labeled as 99.9%,
MPPT efficiency is currently no reliable instrument to measure , do not require
certification measurements , in fact , MPPT efficiency is the most critical
factor in the decision PV off grid inverter generation , far more than the importance of
the efficiency of the PV inverter itself , domestic PV inverters are under the
same conditions as Comparative generating capacity , may differ up to 20% of
this difference is mainly due to MPPT efficiency.
There MPPT students can first understand
the basic principles and implementation methods Baidu MPPT 's . I mainly to
everyone Revealed MPPT efficiency calculation methods and sources , MPPT
efficiency equal hardware efficiency multiplied by the efficiency of software
and hardware efficiency mainly by the accuracy of the current sensor to
determine the accuracy of the sampling circuit , the software efficiency is
mainly determined by the sampling frequency , there are many ways to achieve
MPPT , but no matter which method is used , the first to measure the components
of the power of change, and then react to changes . This is one of the most
critical components is the current sensor , its accuracy and linearity errors
will directly determine the efficiency of the hardware , software and sampling
frequency accuracy by hardware also determined .