The high voltage winding used for domestic transformers is generally connected in a Y connection, while the connection between the medium voltage winding and the low voltage winding depends on the system situation. Situatio sic vocata systemae refert ad relationem inter phasor voltationis systemae transmissionis altae voltationis et phasor voltationis systemae transmissionis minimae voltationis. Si system a distribution is low voltage est, secundum regulas standard determinabitur.
Reage quare venti altae voltationis saepe connectae sunt in connexio Y est quia voltatio phase 57.7% voltationis lineae et voltatio per circulum inferior potest esse.
1). The voltage phasors of domestic transmission systems of 500, 330, 220, and 110kV are all in phase. Therefore, for three-phase three winding or three-phase autotransformers with the following voltage ratios, star connection should be used for both high and medium voltage windings. When the three-phase core column iron core structure is used, the low-voltage winding can also adopt star connection or angle connection, which depends on whether the voltage phasor of the low-voltage transmission system is in phase with or lagging behind the voltage phasor of the medium voltage and high-voltage transmission systems by 30 ° electric angle.
500/220/LVkV - YN, yn0, yn0 aut YN, yn0,d11
220/110/LVkV - YN, yn0, yn0 aut YN, yn0,d11
330/220/LVkV - YN, yn0, yn0 aut YN, yn0,d11
330/110/LVkV - YN, yn0, yn0 aut YN, yn0,d11
2). Duo anguli phase varii sunt voltationis domus 60 kV et 35 kV transmisionis.
Si transformator 220/60kV modo connexionis YN d11 adopt, et conversor 220/69/10kV modo connexionis YN, yn0, d11, est diferencia electrica 30° inter duos transmisionis systemas 60kV.
When the 220/110/35kV transformer adopts YN, yn0, d11 connection method, and the 110/35/10kV transformer adopts YN, yn0, d11 connection method, the voltage phasor of the two 35kV transmission systems also differs by 30 ° electrical angle.
So, when deciding on the connection method for 60 and 35kV windings, caution must be exercised, and the connection method must meet the requirements of the voltage phasor of the transmission system. Determine the connection method of 60 and 35kV windings based on the relative relationship of voltage phasor. Alioquin, etiam si capacitatem et voltationem rationem rectam sunt, transformator non potest usare, methodo connexionis incorrecta est, et transformator non potest connectare ad systemam transmission is potentiae.
3). Duos typos phasor in domo 10, 6, 3, et 0.4kV transmissionis et distributionis sunt. In area Shanghai est tipus 10kV et 110kV transmission is fluctus contra fluctum phasor 60 ° electrici. In hoc tempore tres fases transformatorem ventilatorum electrici cum proportione voltationis 110/35/10kV et YN, yn0, y10 connexionis utilizatur, sed tantum cum tres fases cordis ferreae cordis ferreae tres fases.
4). However, it should be noted that single-phase transformers cannot be connected in three-phase groups using YNy0 connection method. The YNy0 connection method cannot be used for three-phase shell transformers.
When a three-phase five column iron core transformer must use YN, yn0, and yn0 connections, there must be a fourth winding connected in an angular way inside the transformer, and its head shouldn't be brought out (the head that needs to be led out during electrical testing is not included in this example).
5). When transformers with different connection groups are operated in parallel, the general rule is that the connection group numbers must be the same.
6). Quando transformator distribution is in regionibus cum multiplibus stricis fulgorum utilizatur, methodo connexionis Yzn11 utilizatur. Quando methodo z connexionis utilizat, algoritmus impedance voltationis diferentur ab methodo connexionis Yyn0, et consummatio coperii ventoris z connexionis superior est. The Yzn11 connection transformer has good lightning protection performance.
7). YNy0 connection method cannot be used for three-phase transformers with four coiled iron core frames.
8). Altissimus omnes modos connexionis domus transformatoribus utili sunt. Si exportentur, adequate modi connexionis et numeri grupae connexionis iuxta requisum providere sunt.
9). Generally, there are taps and tap changers connected to high-voltage windings. Therefore, when choosing a tap changer (including on load tap changers and off excitation tap changers), it is necessary to pay attention to the coordination between the transformer connection method and the tap changer connection method (including connection method, test voltage, rated current, each level voltage, voltage regulation range, etc.). For the load tap changer used in YN connected on load tap changers, it is also important to note that the midpoint must be pulled out.
