Обзор влияния распределенной генерации на электроэнергетическую систему

В 2020 году суммарная установленная мощность объектов генерации на основе возобновляемых источников энергии (без учета гидроэнергетических объектов) в мире составила около 1437 ГВт, из которых 651 ГВт — пришлось на ветровые электростанции, а 627 ГВт — на солнечные электростанции. Рост установленной мощности объектов распределенной генерации является своеобразным ответом на такие явления как: увеличение энергопотребления, глобальное потепление и ряд других экологических проблем. С технической точки зрения этому во многом способствует развитие технологий в области силовой полупроводниковой техники.
Однако при масштабном внедрении объектов распределенной генерации на основе возобновляемых источников энергии традиционная электроэнергетическая система неизбежно сталкивается с новыми вызовами, связанными с обеспечением надежной и устойчивой работы энергосистемы в целом. В частности, распределенная генерация оказывает влияние на процессы, протекающие в энергосистеме, влияет на параметры режима работы энергосистемы и баланс генерируемой и потребляемой мощности, изменяет величину и направление перетоков мощности и токов короткого замыкания. Это, в свою очередь, обусловливает необходимость пересмотра уставок релейной защиты и автоматики традиционной электроэнергетической системы, а также согласования работы данного оборудования с системой автоматического управления объектов распределенной генерации.
Среди ключевых научных направлений выделяют задачу по определению оптимального размера и размещения объекта распределенной генерации. Основная цель для проведения данной оптимизации заключается в снижении суммарных потерь мощности, а также в сокращении эксплуатационных и капитальных затрат, в повышении уровня напряжения в узлах схемы до допустимых значений нормированного диапазона. Кроме того, оптимальное размещение распределенной генерации позволяет осуществлять эффективное планирование режимов работы электроэнергетической системы в целом и электростанций в частности, особенно на основе возобновляемых источников энергии, режим работы которых во многом определяется суточными и сезонными погодными изменениями и может резко изменяться, в отсутствие обеспечения требуемых показателей электроснабжения конечных потребителей.
В статье выполнен анализ влияния распределенной генерации на потери мощности, уровень напряжения, поддержание баланса мощности и частотное регулирование, а также на величину и направление токов короткого замыкания. Кроме того, осуществлено рассмотрение различных оптимизационных критериев, ограничительных условий и методов решения обозначенной выше оптимизационной задачи распределенной генерации. Данное исследование поможет системному оператору, электросетевым и инвестиционным компаниям нашей страны сформировать целевую функцию и ограничительные условия для выбора оптимального размещения объекта распределенной генерации, позволяющего обеспечить электроснабжение конечных потребителей при минимальных затратах.

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