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جبران طاقت ریاکتیو چطور انجام می شود؟
جبران طاقت ریاکتیو چطور انجام می شود؟

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[حمید]

با تزریق توان راکتیو به سیستم. در واقع جبران سازی راکتیو یک سیستم الکتریکی به نوعی تولید توان راکتیو مورد نیاز سیستم ( بارهای اندوکتیو ) به روشهای اقتصادی و تزریق آن بطور موضعی در نواحی مورد نیاز است. خازنهای قدرت، ساده ترین و مقرون به صرفه ترین المانهای الکتریکی جهت تولید استایک توان راکتیو می باشند. در سیستمهای جبران نشده این وظیفه را بخش تحریک ژنراتورها بعهده می گیرد که از نظر اقتصادی اتلاف منابع محسوب می شود. علاوه بر آن تولید این توان راکتیو در نیروگاه های بزرگ که معمولاً از مراکز مصرف بسیار دورند سبب اشغال بی مورد شبکه انتقال و توزیع می گردد. راستش موضوع مورد نظر شما بسیار گسترده و مفصل است، در زیر کلیاتی در این خصوص آمده. چنانچه سوال یا بحث خاصی وجود دارد بطور مشخص مطرح فرمائید. Most industrial loads such as induction motors operate at moderately low power factors. Around 60% of the utility load consists of motors and hence the overall power factor of the power system is low. Depending on the level of the load, these motors are inherently low power factor devices. The power factor of these motors varies from 0.30 to 0.95, depending on the size of the motor and other operating conditions. Therefore, the power factor level is always a concern for industrial power systems, utilities, and the user. The system performance can be improved by correcting the power factor. The system power factor is given by: Power factor = P / kVA where P and kVA are the real and apparent power, respectively. For example even at 90% power factor, the reactive power requirement is 48% of the real power. At low power factors, the reactive power demand is much higher. Therefore, some form of power factor correction is required in all the industrial facilities. The power factor of any operating system can be lagging or leading. The direction of active and reactive power can be used to determine the nature of the power factor. If both the real and reactive power flow are in the same direction, then the power factor is lagging. If the reactive power flows in the direction opposite to that of the real power, then the power factor is leading. A typical lagging power factor load is an induction motor. A typical leading power factor load is a capacitor. Some typical power factors of industrial plants are presented in Table below. The power factor correction capacitors can be installed at high voltage bus, distribution, or at the load. The power factor correction capacitors can be installed for a group of loads, at the branch location, or for a local load. The benefits due to the power factor correction for the utility are release in system generation capacity, savings in transformer capacity, reduction in line loss, and improved voltage profile. The benefits due to power factor correction to the customer are reduced rate associated with power factor improvement, reduced loss causing lower peak demand, reduced energy consumption, and increased short-circuit rating for the system.

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