1. The tap changer control system is important component of converter control system.

2. On-load tap changer (OLTC) is considered to be one of the important factors that results in voltage collapse.

3. What kinds of equipment does an on-load tap changer comprise?

4. To the scheme of mechanical on load tap changer combined with thyristors, its characteristic of arc suppression is analyzed in details, and a corrected scheme is then present.

5. In order to reduce the times of tap changer operations of transformer, a method for reactive voltage control based on active, reactive load and system voltage sections was proposed in this paper.

6. Both regulating characteristics of on-load tap changer(OLTC)and load characteristics greatly impact power system voltage stability.

7. A transformer with on-load voltage regulation was equipped with to restrain the worsening trend and avoid emergency events when the transformers tap changer did not function well.

8. The article briefly introduces the control mode of the converter tap changer control system, which is including manual control and automatic control, and explain their control characteristic.

9. For instance, the effectiveness of fire-extinguishing device, whether or not necessary to install the tap changer and how to determine the economic ratio of losses between no load and on load.

10. The characteristics, principle and structure of the three-phase pipe-type tap changer are intro duced.

11. Two practical methods are introduced to renovate the power transformer with no-load tap changer into that with on-load one.

12. In general, there are two main ways in power grid in China: the shunt capacitors and under load tap changer(ULTC) of main transformers, which both contribute to the two objectives above.

13. After illustrating the operation theory of six pulse converter, author gives the calculating method of UHVDC transmission parameters such as operating power, voltage, current and tap changer range.

14. The paper brings forward a method to analyze problem of voltage stability by virtue of on-load tap changer model.http:///tap changer.html

15. A second-order nonlinear model is established by adding the voltage of the dummy nodes in the on-load tap changer transformer model to express the power and voltage relations.

16. The apparatus applies a continuous supply of nitrogen to the load tap changer, and has an orifice to maintain a slight overpressure over an extreme range of climatic conditions.

17. This thesis carries out studies aiming at the impact of load characteristics and on load tap changer on voltage stability.

18. A method of switching mutual repulsive thyristors in the process of on - load tap changer is proposed.

19. A non-inrush voltage regulating method is proposed for on load tap changer transformer by using the power electronic devices.

20. If regulating equipment is needed, it may be desirable to provide it in the transformer by using load tap changer equipment.