Posted on 2018-1-25 16:40:50 | Just look at the author | Reverse Look
PV inverter efficiency test
Photovoltaic power generation has become a hot spot in today's and future energy supply in low-voltage power grids. The direct current generated by the solar panel can be stored in the battery system. Normally, this DC power needs to be converted into AC power to the distribution network to meet the daily electricity demand. The conversion from DC to AC will be achieved by a photovoltaic inverter. Figure 1 is a typical
In order to reduce the power loss in the conversion process, the inverter needs to continuously improve efficiency. The typical inverter efficiency is generally around 96%. The power analyzer can measure the energy produced by the solar generator, the efficiency of the inverter and the energy delivered to the grid via the inverter. According to the wiring of the photovoltaic string, each string will have its own maximum power tracker (MTT). Each inverter of a photovoltaic string is a high-power inverter, usually a three-phase AC output.
The LMG670 power analyzer can place up to 7 power modules in a single chassis and can accurately analyze and measure relevant parameters in the entire PV network, such as voltage, current, and power.
LMG600 series power analyzers can be configured to test multiple channels according to test requirements. Figure 2 shows the grid-connected PV inverters. The LMG670 can be configured as six power channels. Each power channel contains one voltage input and one current input.
Typical test input requirements:
1, DC voltage range 600V-1000V, there are now 1500V
2, AC voltage range 230V-400V, depending on the inverter rated power
3, current range 10A-1000A, depending on the inverter rated power
4, bandwidth 10KHz-100KHz, depending on the switching frequency of the inverter
5, accuracy: general field test can use B1 module, laboratory high efficiency test using A1 precision module
LMG600 series power analyzer can be configured with different precision and bandwidth power modules according to different test requirements. Figure 3 shows the accuracy and bandwidth of A1 module and B1 module.
Solar energy conversion efficiency test
You can view the efficiency test results between each group separately under a measurement menu, and you can build a custom menu that shows only the test data that you care about
Using harmonic analysis to test the stability of grid-connected power generation
Voltage, current and power harmonics can be displayed, displayed by harmonics and histograms. To check whether harmonics and interharmonics meet the requirements of photovoltaic grid-connected
The LMX600 series power analyzer flicker test module is used to observe short-time flash PLT and long-time flash PLT. These data have a limited range in grid-connected standards.
Record the power data of the solar power system
Can record for a long time include: voltage, current, power, power factor, frequency, harmonics and analog digital processing signal, irradiance sensor signal and other data, the recorded data can be imported to Excel, MATLAB, OCTAVE and other software for post-analysis processing And view
Observation and Analysis of Inverter Output Waveform Quality
Using the LMG600 software tool, Sample Vision, you can record the sampling point values on the computer without gaps to analyze the voltage and current waveforms generated during the DC-DC and DC-AC conversions in the inverter phase.
