Variable frequency and high speed sampling handheld photovoltaic cell tester and method for achieving same

Abstract

The invention discloses a variable frequency and high speed sampling handheld photovoltaic cell tester and a method for achieving the same. The tester is designed by using a field programmable gate array (FPGA) chip EP2C8T144C6 combined with an analog-to-digital converter (ADC) chip AD9245-40, current voltage sampling points (P1 and P2) access to an input end of a cascade circuit to a programmable amplifier chip, an output end of the cascade circuit is accessed to an analog input port of the AD9245-40, and a 14-bit output of the AD9245-40 is accessed to an input / output (I / O) input port of the EP2C8T144C6. According to the variable frequency and high speed sampling handheld photovoltaic cell tester and the method for achieving the same, the highest sampling rate can achieve 32 MHz, a variable frequency sampling method is used, the problem of unreasonable data distribution is solved, the data redundancy is reduced, an obtained a voltage-current (I-V) curve is smooth, and relevant parameters are accurate and stable.

Description

Technical field [0001] The invention belongs to the field of handheld testers, and specifically relates to a frequency conversion high-speed sampling handheld photovoltaic cell tester and an implementation method thereof. Background technique [0002] At present, the well-known photovoltaic cell module tester that uses a capacitor as an electronic load is designed based on an MCU, and the sampling rate is very limited. And it adopts the method of uniform speed sampling, the current and voltage sampling rate is constant throughout the sampling process. According to the charging voltage-time curve and the charging current-time curve, it can be known that uniform sampling will make the number of sampling points excessively dense in the current-voltage (I -V) The place on the curve is close to the open circuit voltage, which not only wastes limited sampling points, but also makes the sampling points of the main part of the curve sparse, and the dense sampling points cannot be disting...

AI Technical Summary

Problems solved by technology

[0003] In order to obtain more accurate acquisition parameters and smoother I-V curves and reduce data redundancy, the present invention uses FPGA to design, uses FPGA to generate special sampling modules, greatly improves the highest sampling rate of the system, and adopts frequency conversion sampling The method solves the problem of unreasonable data distribution, reduces data redundancy, and obtains a smoother I-V curve, and more accurate and stable related parameters.

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