The transformation ratio of a transformer refers to the voltage ratio between the high voltage side winding and the low voltage side winding of the transformer. Specifically, it represents the ratio of the rated voltage on the primary side to the rated voltage on the secondary side.
Mathematically, the transformer ratio (K) can be expressed as: K = rated voltage on high voltage side/rated voltage on low voltage side.
How to calculate transformer transformation ratio? There are several methods:
1. ratio = number of turns in the primary windings / number of turns in the secondary windings;
2. ratio = input voltage / output voltage
3. ratio = √(rated capacity of the transformer × input voltage) /output voltage
And below is the influence of transformer transformation ratio on power system:
1. Voltage stability Changing transformer transformation ratio will directly affect the voltage stability of power system. Specifically, an increase in the ratio leads to an increase in voltage, while a decrease in the ratio leads to a decrease in voltage. In practice, the variation of the ratio must be carefully controlled to ensure that the voltage stability of the system is within an acceptable range.
2. The change of transformer ratio will also affect the transmission capability of the system. When the transformation ratio is reduced, the rated current of the converter is also reduced, which may lead to a decrease in load capacity. At the same time, the reactive power of the system will also be affected by the change of transformation ratio. Therefore, when adjusting the transformation ratio, the influence on transmission capacity must be fully considered.
3. Transformers are usually wound using iron cores in power systems. Changing the transformer ratio requires readjusting the total flux of the core. If the technology is not properly mastered, it may cause the iron core to be magnetized, thus causing safety hazards. 4. In some special situations, such as inspection and maintenance of power systems during construction, it may be necessary to change the transformer ratio to ensure better operation of the system. However, this also requires careful consideration of the impact of ratio changes on the overall stability and safety of the power system.
