How To Predict Iv Curve Solar Panel Testing
The meter mounts on the side of the lid pointing toward the sun.
How to predict iv curve solar panel testing. The i v curve provides important troubleshooting clues. Reported on block iv and v monocrystalline si systems deployed in florida and found degradation rates well below 1 year 32. For each string the i v tracer measures current and power as a function of voltage. For example if a pv.
Figure 3 maximum power. The i v curve tracer is a electrical test for verifying photovoltaic array performance. I i l i 0 exp q v n k t 1 read more about ideal solar cell. At the isc and voc points the power will be zero and the maximum value for power will occur between the two.
The voltage and current at this maximum power point are denoted as vmp and imp respectively. I v curve tracers are specialist types of test equipment that sweep an electrical load connected to the solar pv module or string and measure both the current and voltage at multiple points during the sweep. We use a shop cart with an adjustable lid. The i v curve of a pv array is a scale up of the i v curve of a single cell as illustrated in figure 4.
In 1977 the department of energy established the solar energy research institute in golden colorado. Keep the panel and solar intensity meter perpendicular to each other 2. Additionally the only way to know if you have purchased high quality panels is through solar panel testing. The 1 term in the above equation can usually be neglected.
If the illumination applied to the solar cell during the iv test is representative of the solar radiation it receives in the field then the maximum efficiency of the solar cell may be calculated as the ratio of pmaxto the optical power incident on the solar cell. Locate the converter box. Scaling i v curves thinking of pv arrays as composites of smaller pv building blocks is key to interpreting electrical measurements in troubleshooting situations. In 1991 it was renamed as the nrel.
A simplified equivalent circuit model of the solar cell. Measured results are compared to the expected results and we can immediately identify a problem and even locate exactly which length of wire connector or module in. Outdoor testing of modules and submodules. Adjust the angle and direction of your panel and meter to achieve a consistent solar intensity.
The power produced by the pv cell in watts can be easily calculated along the i v curve by the equation p iv. The exponential term is usually 1 except for voltages below 100 mv. The panel lies flat on the lid and is secured with magnets. When testing solar panels it is essential that you know how to properly use a multimeter.
The pairs of current and voltage values are then used to plot an i v curve directly or to calculate and plot a p v curve.