Combined heat and power scheduling method based on convex relaxation

Abstract

The invention provides a combined heat and power scheduling method based on convex relaxation, and the method builds a simplified thermodynamic model to describe the water temperature change in a regional heat supply system; non-convex equality constraints and bilinear constraints in the model are relaxed by using cone relaxation and polyhedron relaxation methods, so that a convex CHPD model is obtained, a relaxed solution obtained based on the model is further projected to a feasible solution space, and finally, the CHPD solving quality and calculation performance can be improved. According to the invention, the simplified thermodynamic model about the temperature change of the heat supply network is established, and the mathematical complexity of a node method used in a traditional heatsupply network modeling method is reduced; a convex CHPD model is constructed by utilizing second-order cone relaxation and polyhedron relaxation, and the hydraulic and thermal conditions of DHS are fully simulated. The invention further provides a self-adaptive boundary tightening strategy to improve the quality of the relaxation solution, and the local optimal solution of the combined heat and power scheduling problem can be quickly and effectively found.

Description

technical field [0001] The invention relates to a combined heat and power scheduling method, in particular, a convex relaxation based combined heat and power scheduling method is designed. Background technique [0002] In recent years, the widespread application of combined heat and power (CHP) and heat pumps has strengthened the energy interaction between electric power systems (EPS) and district heating systems (DHS). Therefore, adopting an effective Combined heat and power dispatch (CHPD) method for the coordinated operation of the coupled power and district heating systems can promote the minimization of the operating costs of the entire system and increase the consumption of renewable energy. Sodium level. [0003] For the CHPD problem, it is necessary to model the distribution and heat transfer process of hot water in the heating network. However, the CHPD problem considering grid power flow and district heating energy flow belongs to non-convex nonlinear programming...

AI Technical Summary

Problems solved by technology

However, for the heuristic iterative algorithm, the existing methods often do not take the complex heat flow equation as a model constraint, or only design a feasible strategy for CHPD for a specific scenario and rely on a large amount of experience. Local solutions to non-convex problems with unsatisfactory performance

For the method of model assumption, the heating network is usually simplified to a linear model, which can improve the calculation speed of the solution, but at the expense of the optimality of the solution

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