Cineáltaí Briseadh Ciorcail Ardion & Treoir Fadhbanna

High-Voltage Circuit Breakers: Classification and Fault Diagnosis

Is mótarúilte iad briseoirí circe high-voltage sa chóras fuinnimh. Téann siad ar scor go tapa nuair a tharla deifir, ag cosaint ar tháirgeadh ó lódanna breise nó córais shorcha. Mar gheall ar oibriú fada éigríochta agus cúrsaí eile, d'fhéadfadh briseoirí circe fós a bheith faoi dhéanamh a bhfuil riachtanas orthu a diagnóis agus a dhiúltú.

I. Raghaidh Briseoirí Circe High-Voltage

1. De réir Suíomh Iastail:

• Indoor-type: Iastal i seomraí comhbhrabhsála dúnta.

• Outdoor-type: Dírithe do iastail amach, le boscaí éigeantacha.

2. De réir Meán Scora Airc:

• Oil Circuit Breaker
  Úsáideann sé olion insüláideach mar mhéan scora airc.

• Bulk Oil Circuit Breaker (Multi-oil): Seirbhíonn an olion mar mhéan scora airc agus insüláide idir na cuid beatha agus an bosca talún.

• Minimum Oil Circuit Breaker (Less-oil): Úsáidtear an olion amháin do scora airc agus insüláide contáct; insüláide amach (mar shampla, porseáin) insüláide na cuid beatha ón talún.

• Vacuum Circuit Breaker：Scorann airc in aerchúscáil airde, ag úsáid láidreacht dielectric an aerchúscáil. Forbríonn sé go forleathan i ngniomhaíochtaí meán-voltage mar gheall ar shaol fhada agus coimeád íseal.

• Sulfur Hexafluoride (SF₆) Circuit Breaker：Úsáideann sé ga SF₆—athchúisitear as a phróiseolaíocht scora airc agus insüláide den scoth—mar mhéan scora. Is príomha é i gcórais trasnála high-voltage as ucht iontaofacht agus dearadh comhuaine.

• Compressed Air Circuit Breaker：Úsáideann sé aer choimeádtha chun an t-arc a scoráil agus insüláide a thabhairt tar éis an scora. Níl sé chomh coitianta inniu mar gheall ar chomhshó aonrach agus coimeád.

• Magnetic Blow-Out Circuit Breaker：Úsáideann sé fórsa electromagnecteach chun an t-arc a dhéanamh dul isteach i slite cogaí áirithe áit a rachann sé go fuar agus díonach. Tíospríonn sé go forleathan i ngniomhaíochtaí DC nó AC speisialta.

II. Deifir Chomhchoite agus Díúltú Briseoirí Circe High-Voltage

1. Theip ar Dhúntas (Refusal to Close)

D'fhéadfadh seo bheith mar thoradh ar cheisteanna meicniúla, deifir i gciorcuit stiúir, nó míghníomhaíochta. Seiceáil ciorcuit stiúir leictreach agus comhábhair meicniúla.

Deifir leictreacha:

(1) Lampa léitheoireachta gan oibriú nó neamhrialta

• Seiceáil má dílíontar voltagh cumhachta stiúir le luach réamhdhite.

• Má níos éiríonn an solas dearg nuair atá an spionnóg i "close" position, is dócha gur  open closing circuit no blown fuse.

• Má díríonn an solas glas (trip position) ach níos éiríonn an solas dearg (close position), seiceáil red lamp integrity.

• Má díríonn an solas glas agus éiríonn arís: is féidir low voltage no mechanical failure in operating mechanism.

• Má éireann an solas dearg ar feadh tréimhse ghearr ansin díríonn agus éiríonn an solas glas: dúnadh an briseoir go moillmhar ach theip air a lúcháil— mechanical fault no excessively high control voltage ag déanamh theip tionchar.

(2) Closing contactor does not operate

• Má tá an solas glas as: seiceáil control bus fuses (positive/negative).

• Má tá an solas glas ar: úsáid peann tástála nó multimeter chun control switch, anti-pumping relay, auxiliary contacts, agus seiceáil ar coil open circuit no secondary wiring break.

(3) Closing contactor operates but breaker does not move

• Féidearthachtaí: poor contactor contact, arc chute jamming, open closing coil, or blown AC fuse in closing rectifier.

(4) Closing contactor operates, breaker moves but fails to close fully
Féidearthachtaí:

• Mechanical failure in operating mechanism

• Low DC bus voltage

• Secondary wiring mix-up accidentally energizing trip circuit

• Improper operation (e.g., operator releasing control switch too early)

2. Theip ar Thriop (Refusal to Trip)

Is mór an ngéarraidh ná theip ar dhúnadh, mar gheall ar gur féidir leis an triop tríobháil a dhéanamh (cascade tripping), ag leathnú scóip easpa.

(1) Cúrsaí theipe leictreach

• Red light not lit: indicates open trip circuit.

• Seiceáil: lamp integrity, fuse, control switch contacts, breaker auxiliary contacts.

• Seiceáil: anti-pumping relay coil, trip circuit continuity.

• Trip coil operates weakly: may be due to high coil pickup voltage, low operating voltage, stuck trip plunger, or coil fault.

• Trip plunger moves but breaker does not trip: likely mechanical jamming or detached drive linkage pin.

(2) Handling refusal to trip

• Manual trip fails: Immediately report to dispatch.

• If bypass switch available: transfer load to bypass, open bus-side disconnectors of faulty breaker, then trip bypass breaker to de-energize the circuit.

• Upstream breaker trips due to cascade fault:

• With power off, open disconnectors on both sides of the faulty breaker.

• Manually open all feeders on the affected bus.

• Report to dispatch for system restoration.

3. Unintended Opening or Closing (False Operation)

(1) Unintended Tripping (False Trip)
Occurs when breaker trips without protection activation or operator action. Possible causes:

• Two-point DC grounding in control circuit—check and eliminate ground fault before reclosing.

• Faulty interlock mechanism—isolate breaker (open source-side disconnector) and test close once.

• If evidence suggests internal fault despite no relay activation, investigate accordingly.

(2) Unintended Closing (False Close)
A de-energized breaker closes without command. Causes:

• Two-point DC grounding energizing closing circuit.

• Stuck auto-reclose relay contact.

• Low pickup voltage + high coil resistance, causing false closure during DC transient pulses.

4. Overheating of Circuit Breaker

Main symptoms: overheated tank (especially in minimum-oil breakers), heated frame.

• Cause: Poor contact or oxidation in conductive parts.

• Risks: Insulation damage, cracked porcelain, smoking, oil spraying, or even explosion.

• Action: Strengthen patrols, detect early, and address promptly.

5. Other Common Faults

(1) Oil Circuit Breaker Fire
Fire may result from dirty or damp bushings causing ground flashover, or internal arcing.

• If fire just started: Immediately remotely trip the breaker.

• If fire is severe: Use upstream breaker to isolate the circuit, then open disconnectors on both sides to fully isolate the unit. Extinguish with dry-type fire extinguisher (e.g., CO₂ or powder).

(2) Trip/Close Coil Smoking
Trip/close coils are designed for short-time duty. Prolonged energizing causes overheating and burnout.

• Action: Immediately report to dispatch and request replacement.

• If closing fuse blows during operation, replace only with specified rating—never use oversized fuse to prevent coil damage.

(3) Emergency Manual Trip Required
Immediately take oil circuit breaker out of service if any of the following occur:

• Severe porcelain insulator cracking, flashover, or explosion

• Melting or disconnection of conducting parts

• Loud internal arcing sounds

• Severe oil deficiency

Summary

This guide provides a comprehensive overview of high-voltage circuit breaker types, common operational faults, and corrective actions. Proper classification, regular inspection, and prompt troubleshooting are essential for ensuring system reliability, personnel safety, and equipment longevity.