Application Study on Zero Output Technology of Low Pressure Cylinder of 350MW Supercritical Unit

Abstract

In response to the requirement of national thermal power flexibility reform policy and the need of regional central heating development, a 350MW supercritical unit in a power plant has been transformed with zero output technology of low pressure cylinder. In this paper, the scope and content of low pressure cylinder zero output transformation are discussed, peak shaving and heating capacity after transformation are analyzed, the difference between operation effect and calculation result after unit transformation is compared by test, and the matters needing attention in future operation are given, which provides reference for technical transformation of low pressure cylinder zero output of other power plant units.

Operational optimization on large‐scale combined heat and power units with low‐pressure cylinder near‐zero output

“…The unit operates in the LP-ZO mode as: (14) where f Q ( ) ij EF represents the constraint relationship when the thermal load is Q ij .…”

“…The CHP units transformed by LP-ZO can switch flexibly between the high backpressure and extraction condensing operational modes, which increases the flexibility of CHP operations compared with high backpressure for heating. 14 Research on the economic performance and safety of CHP units with LP-ZO is equally important. Ge et al 15 developed a 330 MW unit model with LP-ZO using the Ebsilon software to analyze the thermodynamic characteristics and heating capacity of the unit after transformation.…”

“…The low‐pressure cylinder near‐zero output (LP‐ZO) technology overcomes the disadvantage of inflexibility in high backpressure operations. The CHP units transformed by LP‐ZO can switch flexibly between the high backpressure and extraction condensing operational modes, which increases the flexibility of CHP operations compared with high backpressure for heating 14 …”