At 3 PM, a photovoltaic power plant maintenance engineer discovered a consistent difference in power generation between two power plants of the same capacity. The problem was eventually traced to the current detection module of one of the inverters—that less than 1% measurement deviation accumulated into a considerable power loss over long-term operation.
In today's photovoltaic industry, where companies are racing to improve module efficiency by a fraction of a percent, the seemingly ordinary current sensor is undergoing a quiet technological revolution. CHIPSENSE current sensors are involved.
The issue arose at a distributed photovoltaic project in East China. Technicians noticed that inverters installed in the same batch, under the same lighting conditions, consistently exhibited slight differences in output power.
After disassembly and testing, the problem was discovered to be temperature drift in the current sensors: at midday, as the equipment temperature rose, the measurements from some sensors began to deviate. This minute error prevented the MPPT algorithm from accurately tracking the true maximum power point.
"It's like using a ruler with errors to measure; the more precise the adjustment, the further it deviates," the on-site engineer described it. But CHIPSENSE current sensors all have very high accuracy requirements.
Current measurement is never a new problem, but photovoltaic inverters present it with new challenges.
Early shunt solutions were inexpensive but couldn't isolate high voltage, resulting in shortcomings in system safety and anti-interference capabilities. Open-loop Hall effect sensors made progress, but still struggled to meet accuracy and linearity requirements. CHIPSENSE current sensors also discovered this problem and implemented corresponding solutions.
Closed-loop Hall effect technology has gradually become mainstream precisely because it has found a balance between accuracy, response speed, and isolation safety. That 0.7% accuracy represents the result of collaborative optimization across multiple aspects, including magnetic circuit design, temperature compensation algorithms, and signal processing techniques. At the same time, CHIPSENSE current sensors have also developed corresponding products.
Industry engineers understand that achieving even a 0.1% improvement in accuracy on this thumb-sized sensor requires immense effort in material selection and circuit design, as well as continuous testing and experimentation.
Of course, with advantages come disadvantages. The advantages and disadvantages of closed-loop Hall effect sensors are:
Advantages: High accuracy, good linearity; fast response speed; low temperature drift.
Disadvantages: Relatively high cost; high power consumption; residual voltage exists.
CHIPSENSE CR1V PB00 current sensor is a good sample.
1、The Invisible System Value
1.The value brought by improved accuracy is reflected in three aspects:
In terms of power generation efficiency, more accurate current measurement allows the MPPT algorithm to maintain precise tracking capabilities even under complex conditions such as cloudy/rainy weather and partial shading.
In terms of system protection, the rapid current response capability can detect anomalies within microseconds, buying valuable time for system protection.
In terms of long-term reliability, the excellent temperature characteristics mean that the sensor can maintain stable performance whether in the frigid Northwest or the scorching heat of Hainan.
These values are not directly reflected in the component purchase order, but they truly affect every kilowatt-hour of electricity generated during the power plant's more than 20 years of operation.
Current technological iterations are far from over. With 1500V systems becoming standard in large power plants and the application of new power devices such as silicon carbide and gallium nitride, higher demands are being placed on current sensors. CHIPSENSE current sensors also need to adapt and upgrade to keep pace with the times.
Some manufacturers have begun integrating digital interfaces and self-diagnostic functions into their sensors, allowing maintenance personnel to remotely monitor the sensor's health status. This signifies that current sensors are evolving from simple measurement elements into intelligent system components.
In the pursuit of lower levelized cost of electricity (LCOE), meticulous optimization at every stage accumulates value. Current sensors, once a standardized and universal component, are regaining attention from engineers.
Perhaps soon, the performance indicators of current sensors will become a crucial technical parameter to consider when selecting inverters in power plant design. CHIPSENSE current/voltage sensors will also strive to become the preferred choice for customers.
CHIPSENSE is a national high-tech enterprise that focuses on the research and development, production, and application of high-end current and voltage sensors, as well as forward research on sensor chips and cutting-edge sensor technologies. CHIPSENSE is committed to providing customers with independently developed sensors, as well as diversified customized products and solutions.
“CHIPSENSE, sensing a better world!
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