Which is better for infrared temperature measurement or fiber optic temperature measurement of new energy photovoltaic inverters

Fiber optic temperature sensor, Intelligent monitoring system, Distributed fiber optic manufacturer in China

The reasons for the temperature rise and heating of new energy photovoltaic inverters

The rapid development of smart grids and new energy has led to significant advancements in power electronics technology for pulse width modulation control. The power consumption issue of power electronic switching devices is an important factor limiting energy conversion efficiency, especially in high voltage and high-power applications. Power electronic switching devices are affected by switching frequency, making it difficult to fundamentally eliminate switching losses. Excessive power consumption can lead to excessively high operating temperatures of the switching devices, which not only affects system efficiency but also has a certain impact on the safe and stable operation of the system.

In recent years, the development of photovoltaic greenhouses has been increasingly rapid, and various types of greenhouses have emerged one after another. Photovoltaic greenhouses are being applied in more and more areas. There are more and more types of photovoltaics, and after photovoltaic power generation, inverters are needed to convert the DC of photovoltaic power generation into AC, and then connect it to the grid for transportation. The temperature inside the photovoltaic inverter needs to be controlled within a reasonable range. Excessive temperature can cause a sharp decrease in the efficiency of the photovoltaic inverter and also have a significant impact on its lifespan.

Temperature rise in solar photovoltaic systems

With the rapid growth of electricity demand in our country, the application range of solar photovoltaic systems in the power system is becoming wider and wider. The existing solar photovoltaic system mainly consists of solar panels, controllers, inverters, batteries, etc. Due to the fact that solar photovoltaic systems are often operated under long-term sunlight, their structural performance and high-temperature resistance service life are key design points in existing technologies. The usage environment of photovoltaic inverters is limited by solar power plants, and they are generally installed in remote areas with harsh natural environments. The inverter environment has certain requirements for temperature, humidity, and cleanliness. Especially for inverters used in solar photovoltaic systems, which are located in remote areas with frequent exposure to sunlight, anti magnetic interference and protective cleaning are the focus of their design. In recent years, the photovoltaic industry has developed rapidly. Photovoltaic inverters are one of the core equipment for photovoltaic power generation. They work in high current and strong magnetic field environments for a long time and are prone to local overheating, resulting in fires and large-scale power outages. However, the climate conditions in different locations are diverse, and the results of laboratory type tests cannot reflect the temperature rise of inverters on site in photovoltaic power plants.

What are the temperature measurement methods for inverters

In terms of on-site temperature rise testing for inverters, there are currently mainly infrared temperature measurement method, fiber optic temperature measurement method, and acoustic surface temperature measurement method.

The temperature measurement of power electronic switching devices in traditional inverters is achieved through infrared thermal imagers, which measure the temperature value of inverter switching devices by taking thermodynamic images of the required measurement area. However, infrared thermometers have many drawbacks, such as being able to only determine the measurement value of the target area based on the captured images, which leads to the inability to obtain current data in a timely and accurate manner; In addition, personnel are also required to conduct on-site measurements, as there is a certain level of danger in high-pressure situations and there is no good operability
Sex; The measurement accuracy of thermal infrared imagers is not high, and the price is also relatively expensive.

The principle of infrared temperature measurement method

According to the blackbody radiation law, the surface temperature of an object is determined by measuring its own infrared radiation energy. The commonly used handheld infrared thermal imager is a typical non-contact measurement method that requires manual operation, cannot achieve uninterrupted online measurement, cannot measure internal equipment through the cabinet door (the cabinet door must be closed when the inverter is running), and is susceptible to factors such as temperature, pollution, and interference.
Online infrared temperature measurement method is another non-contact temperature measurement method, which requires the measured point to be in the field of view and unobstructed, the surface must be clean to ensure accuracy, and it is susceptible to environmental and surrounding electromagnetic interference during testing. In addition, the space inside the switchgear is very small, making it difficult to install infrared temperature probes. In addition, there are many factors that affect infrared radiation and they are time-varying, making it difficult to calibrate them one by one. Therefore, this method has poor universality and cannot be widely used.

The acoustic surface temperature measurement method uses passive wireless sensors, but is limited by the frequency bandwidth splitting principle and signal simulation processing technology of the acoustic meter temperature measurement. It has the disadvantages of being easily interfered with and having poor scalability, and is prone to temperature measurement interruption or significant data jump. Too many sensors cannot be installed, otherwise the receiving system cannot distinguish.

Inverter fiber optic temperature measurement

Temperature testing is conducted based on the principle of optical time-domain reflection in optical fibers and the temperature effect of backward Raman scattering in optical fibers. Fiber optic has excellent insulation performance and can isolate high voltage inside the inverter cabinet. Fiber optic temperature sensors can be directly installed on the high voltage contacts inside the cabinet to accurately measure the operating temperature of the high voltage contacts.

The inverter fluorescent fiber optic temperature monitoring system installs fiber optic temperature sensors on the corresponding inverter switch devices, and then obtains the temperature of the inverter switch devices in a timely manner through the fluorescent fiber optic temperature controller, improving the accuracy of temperature detection; Further storage and display of relevant temperature data through LCD display screens facilitates technical personnel’s query.

FJINNO provides inverter temperature measurement system and inverter temperature monitoring host at a reasonable price. Welcome to contact the agent by phone for cooperation!