Explicatio Detalis de Quibusdam Questionibus et Solutionibus pro Condensatoribus Altae Tensionis
Problema Tensionis Operativae Condensatoris
Magnitudo tensionis operativae condensatoris significanter influet in eius vitam utilem et capacitate productivam, faciens eam indicatorem clavem in systemate busbar substationis. Perdita potentiae activae intra condensatorem principaliter origo ex perdita dielectrica et perdита проводимости, где диэлектрические потери составляют более 98%. Диэлектрические потери оказывают значительное влияние на рабочую температуру конденсатора. Это влияние можно выразить следующей формулой:
Pr = Qc * tgδ = ω * C * U² * tgδ * 10⁻³
Ubi:
- Pr repraesentat perdita potentiae activae condensatoris altae tensionis
- Qc denotat potentiam reactivam eius
- tgδ est tangens perdиты диэлектрических, где диэлектрические потери составляют более 98%. Диэлектрические потери оказывают значительное влияние на рабочую температуру конденсатора. Это влияние можно выразить следующей формулой:
- ω est frequencia angular rete electricum
- C est capacitance condensatoris
- U est tensionis operativae condensatoris
Ut patet ex formula supra, perdita potentiae activae (Pr) condensatoris altae tensionis directe proportionalis est quadrato tensionis operativae suae (U²). Cum tensionis operativa crescere, perdita potentiae activae rapiditer crescit. Hoc incrementum rapidum ad augmentum caloris ducit, consequenter affectans vitam insulatorii condensatoris. Praeterea, operation longa condensatoris sub conditionibus overvoltage causabit overcurrent, potencialiter danificans condensatorem. Ergo, systemata condensatorum altae tensionis requirunt dispositiva protectionis overvoltage comprehensiva.
▲ Impactus Harmonicorum Superiorum Ordinum
Harmonici superiorum ordinum intra rete electricum etiam adversae possunt influere in condensatores. Quando currentes harmonicorum fluitant in condensatorem, superponuntur ad currentem fundamentalem, augmentantes valorem culminem currentis operativi et tensionis fundamentalis. Si reactantia capacitive condensatoris congruit cum reactantia inductive systematis, harmonici superiorum ordinum amplificantur. Haec amplificatio potest causare overcurrents et overvoltages, potentialiter ducens ad discharge partialis intra dielectricum insulatorium internum condensatoris. Talis discharge partialis potest provocare defectus sicut bulging et group fuse blowing.
▲ Problema Loss-of-Voltage Busbar
Loss of voltage on the busbar to which the capacitor is connected is another critical concern. A capacitor that suddenly loses voltage during operation can cause tripping on the substation supply side or disconnection of the main transformer. If the capacitor is not promptly disconnected under such conditions, it may experience damaging overvoltage. Additionally, failure to remove the capacitor before voltage restoration can lead to resonant overvoltage, potentially damaging the transformer or the capacitor itself. Therefore, a loss-of-voltage protection device is essential. This device must ensure the capacitor reliably disconnects after voltage loss and reliably reconnects only after voltage has been fully restored to normal.
▲ Overvoltage Induced by Circuit Breaker Operation
Circuit breaker operation can also generate overvoltage. Since vacuum circuit breakers are predominantly used for capacitor switching, contact bounce during the closing operation may trigger overvoltage. Although these overvoltages have a relatively low peak, their impact on capacitors must not be overlooked. Conversely, during circuit breaker opening (disconnection), the potentially generated overvoltages can be significantly higher and may puncture the capacitor. Therefore, it is essential to implement effective measures to mitigate the overvoltage produced during circuit breaker operations.
▲ Capacitor Operating Temperature Management
The operating temperature of capacitors is also a critical factor. Excessively high temperatures negatively impact a capacitor's service life and output capability, necessitating proactive control and management measures. Significantly, the rate of capacity decline doubles for every 10°C increase in temperature. Capacitors operating long-term under high electric fields and elevated temperatures experience gradual aging of their insulating dielectric. This aging leads to increased dielectric loss, subsequently triggering a rapid internal temperature rise. This not only shortens the capacitor's operational lifespan but, in severe cases, can even lead to failure due to thermal breakdown.
To ensure the safe operation of capacitors, relevant regulations explicitly stipulate:
- When the ambient temperature exceeds 30°C, ventilation devices should be activated to provide cooling.
- If the ambient temperature reaches or exceeds 40°C, capacitors must be deactivated immediately.
Therefore, a temperature monitoring system must be implemented to continuously track the operating temperature of capacitors in real-time. Additionally, forced-air ventilation measures are crucial to improve heat dissipation conditions, ensuring the generated heat is effectively and efficiently expelled through effective convection and radiation.
