The switching principle of thyristor assistant arc extinguishing hybrid on-load tap-changer

Benping Ding,Xingying Zhao,Taoyuan Cai,I Barukčić,Luning Hao,Pengfei Jia,Fei Shi,Lei Zhang

doi:10.1051/matecconf/202133601016

Benping Ding, Xingying Zhao + Show 6 more

Open Access

https://doi.org/10.1051/matecconf/202133601016

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Abstract

Thyristor assistant arc extinguishing hybrid on-load tap-changer uses thyristor auxiliary mechanical switch which combines the advantages of mechanical switch and thyristor switch. The hybrid OLTC has high reliability, a relatively small amount of work needs to be maintained. It is a kind of very promising transformer OLTC. This project focus on the application of the hybrid OLTC in 110, 220kV transformer, introduces the auxiliary thyristor arc hybrid on-load tap-changer principle of passive trigger with odd block switch to even block as an example, describes the hybrid on-load tap-changer switching process, and the switching principle of simulation verification, on the basis of summarizing the characteristics of hybrid on-load tap-changer.

Highlights

Auxiliary thyristor arc hybrid on-load tap-changer, retained the mechanical on-load tapchanger tap selector and switch, switch circuit increases the reverse parallel thyristor, by breaking the parallel thyristor to auxiliary machinery complete switch contact.After the completion of the parallel switching thyristor exit current-carrying loop, performed by mechanical contact load flow
In order to achieve the passive of thyristor trigger, on the basis of the research team at the early stage of the preparatory proposes a combined with existing KM tap-changer and hybrid on-load tap-changer switching principle of modified auxiliary thyristor arc hybrid on-load tap-changer switch principle, the scheme using three groups of basic circuit, thyristor can achieve the passive of thyristor trigger and withdrawal mechanism, and can make full use of existing KM type on-load tap-changer of other parts, advantages of low cost and good extensibility
Current of thyristor conduction, is transferred to the thyristor branch, the first current passing zero thyristor switch off naturally, maximum conduction time is not more than half a cycle, when the design according to the half cycle time to consider, and considering the mechanical error control at about 12ms; Closed AB branch, 1-4 touch head closure, thyristor trigger conduction not, at this time, no arc, the middle contact [2,3] closed, among them [2,3] after the close contact between the tap the voltage between the formation of the conditions of the thyristor conduction, trigger conduction thyristor, inhibition of contact between the discharge

Summary

Introduction

Auxiliary thyristor arc hybrid on-load tap-changer, retained the mechanical on-load tapchanger tap selector and switch, switch circuit increases the reverse parallel thyristor, by breaking the parallel thyristor to auxiliary machinery complete switch contact.After the completion of the parallel switching thyristor exit current-carrying loop, performed by mechanical contact load flow. In order to achieve the passive of thyristor trigger, on the basis of the research team at the early stage of the preparatory proposes a combined with existing KM tap-changer and hybrid on-load tap-changer switching principle of modified auxiliary thyristor arc hybrid on-load tap-changer switch principle, the scheme using three groups of basic circuit, thyristor can achieve the passive of thyristor trigger and withdrawal mechanism, and can make full use of existing KM type on-load tap-changer of other parts, advantages of low cost and good extensibility

Passive triggered thyristor principle

The hybrid on-load tap-changer switching process

Conclusion