Photovoltaic modules are important equipment for converting solar energy into electrical energy, but they may suffer from the PID (Potential Induced Degradation) effect in long-term operation. In order to ensure the performance and reliability of photovoltaic modules, the International Electrotechnical Commission (IEC) has developed a series of standards, including testing requirements for PID. The PID Tester from Millennial Solar helps evaluate the performance degradation of photovoltaic modules in a PID environment.

Why do PID testing?

PID testing is the process of evaluating the performance degradation of photovoltaic modules under high temperature and high humidity conditions. This attenuation is mainly caused by potential differences in the photovoltaic modules. In photovoltaic modules, a capacitor is formed between the cells, glass, and backsheet. When the humidity and temperature increase, the charges in the capacitor will migrate, resulting in a potential difference. This potential difference will cause the working state of the solar cells to change, thereby leading to performance degradation.

The occurrence of PID is mainly related to the following factors:

- Environmental conditions: High temperature, high humidity, high saline and other environments will accelerate the occurrence of PID, especially in coastal areas.

- External voltage: Photovoltaic modules are connected to inverters, frames, grounding and other components in the power station, forming a certain voltage deviation, causing the cells to be subject to positive or negative bias.

- Component structure: Different types of cells (such as P-type or N-type), packaging materials, glass, etc. have different sensitivity and resistance to PID.

PID effect

International standards for PID detection

In order to evaluate the PID effect of photovoltaic modules, IEC has developed a series of international standards, the most commonly used of which is the IEC 62804 standard. This standard specifies the methods and requirements for PID testing, including testing parameters such as temperature, humidity, and voltage. According to the standard, PID testing should be conducted at a temperature of 85°C, humidity of 85%, and a duration of 96 hours. During the test, a certain voltage is applied to evaluate the performance attenuation of the photovoltaic module. According to the IEC 62804 standard, it is required that the power attenuation of the module does not exceed 5%, there is no appearance failure, the wet leakage current complies with the IEC 61215 standard, and the module function is complete.I-V curve (before and after PID effect test)

I-V curve (before and after PID effect test)

PID Tester

E-mail:market@millennialsolar.cn

Introduction:

Long-term leakage current will cause changes in the state of the cell carriers and depletion layer, corrosion of the contact resistance in the circuit, and electrochemical corrosion of packaging materials.

This results in cell power attenuation, increased series resistance, reduced light transmittance, delamination and other phenomena that affect the long-term power generation and life of photovoltaic modules.

Fulfill the standard:

Meets the MQT21 clauses in the IEC61215 standard and the IEC62804 standard

Features:

•The frame end of the module is grounded, which not only simulates the actual situation, but also prevents potential dangers caused by high voltage on the frame;

•For each photovoltaic module, 4-wire test method is adopted, with 2 high-voltage wires and 2 ground wires;

•Each channel is independent of each other, and the voltage size, polarity and time of multiple channels can be set independently;

•Multiple voltages, leakage current, and insulation resistance are displayed simultaneously;

•Real-time monitoring of voltage, leakage current, and insulation resistance curves;

•All monitoring data can be exported to Excel, CSV, and other format files

•You can enter the photovoltaic module serial number, test time period, and test name to query historical data and curves

Damp Heat Test Chamber

E-mail:market@millennialsolar.cn

Introduction:

Solar modules will withstand various harsh weather tests during their application. Among them, the performance of photovoltaic modules such as their ability to withstand high temperatures, high humidity, and long-term moisture penetration needs to be evaluated. The damp heat test is used to verify and evaluate the reliability of photovoltaic modules or materials and to identify manufacturing defects early through thermal fatigue-induced failure modes.

Fulfill the standard:

IEC61215-MQT13; IEC61730-MST53

Features:Continuous operation for more than 1,000 hours at 85°C and 85%RH requires ultra-high stability, both in terms of manufacturing process and reliability of electronic equipment.

•Built-in circulating air duct and long-axis ventilator for effective heat exchange, making the temperature inside the environmental box uniform and stable

•Adopt imported temperature controller to realize multi-stage temperature programming with high precision and good reliability

•Can operate in continuous high temperature and high humidity environment,High and low temperature interactive tests can also be carried out according to the plans of the engineering staff.

•With a Potential Induced Degradation (PID) Tester, you can more intuitively observe the performance of components

•Temperature fluctuation: ±0.5℃

•Humidity fluctuation: ±2.0%RH

Photovoltaic module PID testing is an important step to ensure the performance and reliability of photovoltaic modules. By following IEC standards, the performance degradation of photovoltaic modules under high temperature and high humidity conditions can be evaluated, which helps manufacturers select high-quality photovoltaic modules and take measures to mitigate the impact of the PID effect. PID Tester from Millennial Solar complies with the requirements of relevant international standards and specifications, and is of great significance to the promotion of solar power generation technology and industrial development.