Low Voltage Self-Healing Shunt Capacitor

In modern industrial production, voltage sags have become a prominent challenge affecting the quality of continuous power supply and the stability of production. Many sensitive loads, such as precision machine tools, automated control systems, and frequency converters, may trip and stop due to short-term voltage drops, causing significant economic losses to the users. As the fundamental core equipment for low-voltage reactive power compensation, Low Voltage Self-Healing Shunt Capacitors are playing an increasingly important role in alleviating voltage sags. However, how to scientifically evaluate the effectiveness of Low Voltage Self-Healing Shunt Capacitors in improving voltage sags is the key basis for users to make decisions on how to select and configure solutions.

Voltage sag mainly refers to the sudden drop in the effective value of the grid voltage within a short period of time. Its root cause often lies in short-circuit faults occurring in the power grid or the startup of large-capacity motors, which draw a large amount of reactive power in an instant, causing a sudden increase in the voltage drop across the line impedance, resulting in a drop in the voltage at the remote common connection point. At this moment, the Low Voltage Self-Healing Shunt Capacitors becomes an "on-site reactive power source". When a voltage sag occurs, the Low Voltage Self-Healing Shunt Capacitors can instantly release the reactive power they have stored, providing local support for the reactive current required by the load, which reduces the reactive power transmitted through the line impedance, thereby raising the voltage level on the load side. This rapid response to voltage sag is based on the physical characteristics of the capacitors, with their speed being much faster than the operation of mechanical switches, and they can offer local support within a few milliseconds.

To scientifically evaluate the effectiveness of Low Voltage Self-Healing Shunt Capacitors in improving voltage sags, users must establish a quantifiable index system. The primary quantifiable assessment indicator is the depth of voltage sag improvement, which is determined by comparing the lowest voltage points caused by the same fault event before and after the installation of capacitors. The difference between the two lowest points is the improvement amplitude. For example, raising the voltage from 0.7 pu to 0.8 pu means that the capacitors have improved the voltage sag by 20% in depth. The second indicator that needs to be quantified for assessment is the change in the duration of the sag, as effective reactive power support can shorten the time required for the voltage to return to the normal threshold. The third key indicator that needs to be quantified for assessment is the reduction in the area of voltage sag. This is a two-dimensional indicator that combines depth and duration, and can be obtained by calculating the area between the voltage deviation curve and the rated voltage line. The reduction in area directly reflects the overall severity of the power quality event being alleviated. Finally, but not the least important, the key indicator that needs to be quantified for assessment is the transient stability time of the system after the compensation device is put into operation, that is, the time required for the voltage to oscillate from the lowest point of the sag to the stable value.

Geyue Electric is well aware that precise quantitative assessment cannot be achieved without high-performance and fast-response compensation equipment as the foundation. Our low-voltage reactive power compensation solution is specifically designed to address the complex challenges of modern power grids. The core of our solution employs Low Voltage Self-Healing Shunt Capacitors with extremely low self-discharge rate and excellent transient response characteristics, ensuring rapid and sufficient reactive power support in the event of voltage disturbances. At the same time, our intelligent control system is equipped with high-speed sampling and advanced algorithms, capable of real-time capturing grid fluctuations and optimizing the switching strategy of the capacitors. Choosing Geyue Electric's solution means you not only receive reliable hardware equipment, but also a complete system that can continuously monitor, actively intervene, and evaluate the voltage quality. We at Geyue Electric are committed to helping every customer elevate the management of power quality from qualitative description to the new level of precise quantification, ensuring the protection of your critical production processes and minimizing operational risks caused by voltage sags.