Instrumentation and Control Journal

Dissolved Gas Analysis (DGA) is one of the most widely used diagnostic tool for detecting and evaluating faults in the electrical equipment, highlight B. Sitharaman, Dr. Vivek Dhole and A. Soundankar.

Electronic systems are designed to run on clean, well regulated, distortion free power.
Heavy machinery, storms, utility issues, power factor correction capacitor switching, and harmonic generating electronics will add voltage distortion to a power system.
A minor power disturbance lasting only a fraction of a second can contaminate or completely ruin data that might take days or weeks to replace.
An entire process can be shut down due to voltage disturbances, noise or impulses, which may result in loss of production and revenue.
Severe line disturbances can, also, reduce the life span, damage or completely destroy expensive equipment.
Constant Voltage Transformer A power conditioner is commonly used to protect sensitive or expensive electronics from these damaging and disruptive events.
There are many different styles of “power conditioners” on the market today, each protecting from a specific distur- The first step in any power quality strategy is developing a complete understanding of the electrical environment, implementing a good power distribution system design using good grounding techniques, highlight Mike Johnson and Jill Normandin.
Power Conditioning for bance or set of disturbances.
It is the purpose of this article to help clarify the term power conditioning and focus on the application of one device that protects from a wide range of disturbances, the Constant Voltage Transformer or CVT for short.
By IEEE definitions, a power line conditioner is a device that combines one or more“power-enhancement” attributes.
Technologies fitting this description include electronic voltage regulators, tapswitching products, buck-boost auto-transformers, which incorporate surge suppression or noise filters and the constant voltage transformer.
The CVT uses ferro-resonant technology to provide reliable, comprehensive power protection in one single unit.
A PC, PLC or combination of both control most industrial equipment. These controllers are critical for day-to-day operation as damage and downtime due to power related events cannot be tolerated.
The CVT is one of the few devices available that can reliably protect from such wide range of disturbances.
No other power conditioner protects from as many different disturbances.
In fact, only a double conversion Uninterruptible Power Supply (UPS) with isolation can offer similar protection at a comparable price.
A UPS solution will increase protection from interruptions but provide decreased reliability.
If power interruptions are not the predominate concern, the CVT is the better choice.
There are several CVT designs in the market, but all incorporate the same basic design - a saturating transformer preloaded with a resonant tank circuit.
The transformer’s reluctance and internal capacitor form this tank circuit, which provides a “pool” of power that supplies constant, clean output voltage free from most types of power disturbances.
Since the transformer is always in saturation, input voltage fluctuations have very little effect on the output voltage.
At light loads, input variation effects
decrease so that at less than 25% load, the input can drop below 60% of nominal continuously with less than a 10% fluctuation in output. Of course, all good things come at a price. In this case, efficiency. Because there is a fixed amount of power required to maintain saturation, the CVT is less efficient at light loads.