Integrated Heat and Electricity Dispatch for District Heating Networks with Constant Mass Flow: A Generalized Phasor Method

This paper develops a nonlinear analytical algorithm for predicting the probabilistic mass flow of radial district heating networks based on the principle of heat transfer and basic pipe network theory. The use of a nonlinear mass flow model provides more accurate probabilistic operation information for district heating networks with stochastic heat demands than existing probabilistic power flow analytical algorithms based on a linear mass flow model. Moreover, the computation is efficient because our approach does not require repeated nonlinear mass flow calculations. Test results on a 23-node district heating network case indicate that the proposed approach provides an accurate and efficient estimation of probabilistic operation conditions.

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Integrated Heat and Electricity Dispatch for District Heating Networks with Constant Mass Flow: A Generalized Phasor Method

10.36227/techrxiv.12547091.v1 ◽

2020 ◽

Author(s):

Yuwei Chen ◽

Qinglai Guo ◽

Hongbin Sun ◽

Zhaoguang Pan

Keyword(s):

Mass Flow ◽

Electrical Power ◽

Thermal Inertia ◽

District Heating ◽

Continuous Model ◽

Discrete Models ◽

Convex Programming Problem ◽

Algebraic Equations ◽

Constant Mass ◽

Electrical Power System

Using thermal inertia in district heating systems (DHSs) to improve the dispatch flexibility and economy of integrated heat and electricity systems (IHESs) is a research hotspot and difficulty. In most existing studies, the partial differential equations (PDEs) of thermal inertia are approximated by discrete-time models, making it difficult to accurately describe the continuous dynamic processes. In this paper, we propose a novel generalized phasor method (GPM) for thermal inertia in DHSs with constant mass flow. Based on the analytical solution of the PDEs and the Fourier transform, the intractable PDEs are transformed into a series of complex algebraic equations represented by phasors. The GPM has higher accuracy compared to traditional discrete models because it is essentially a continuous model in the time domain. Then, we present a different representation of an integrated heat and electricity dispatch (IHED) model combining a DHS model in phasor form and a traditional electrical power system model. The IHED model is a convex programming problem and can be easily solved. The effectiveness of the proposed GPM and dispatch model is verified in three test systems. Compared with traditional methods for modeling the thermal inertia, the proposed GPM is more accurate.

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Integrated Heat and Electricity Dispatch for District Heating Networks with Constant Mass Flow: A Generalized Phasor Method

10.36227/techrxiv.12547091 ◽

2020 ◽

Author(s):

Yuwei Chen ◽

Qinglai Guo ◽

Hongbin Sun ◽

Zhaoguang Pan

Keyword(s):

Mass Flow ◽

Electrical Power ◽

Thermal Inertia ◽

District Heating ◽

Continuous Model ◽

Discrete Models ◽

Convex Programming Problem ◽

Algebraic Equations ◽

Constant Mass ◽

Electrical Power System

Using thermal inertia in district heating systems (DHSs) to improve the dispatch flexibility and economy of integrated heat and electricity systems (IHESs) is a research hotspot and difficulty. In most existing studies, the partial differential equations (PDEs) of thermal inertia are approximated by discrete-time models, making it difficult to accurately describe the continuous dynamic processes. In this paper, we propose a novel generalized phasor method (GPM) for thermal inertia in DHSs with constant mass flow. Based on the analytical solution of the PDEs and the Fourier transform, the intractable PDEs are transformed into a series of complex algebraic equations represented by phasors. The GPM has higher accuracy compared to traditional discrete models because it is essentially a continuous model in the time domain. Then, we present a different representation of an integrated heat and electricity dispatch (IHED) model combining a DHS model in phasor form and a traditional electrical power system model. The IHED model is a convex programming problem and can be easily solved. The effectiveness of the proposed GPM and dispatch model is verified in three test systems. Compared with traditional methods for modeling the thermal inertia, the proposed GPM is more accurate.

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Integrated Heat and Electricity Dispatch for District Heating Networks with Constant Mass Flow: A Generalized Phasor Method

10.36227/techrxiv.12547091.v2 ◽

2020 ◽

Author(s):

Yuwei Chen ◽

Qinglai Guo ◽

Hongbin Sun ◽

Zhaoguang Pan

Keyword(s):

Mass Flow ◽

Electrical Power ◽

Thermal Inertia ◽

District Heating ◽

Continuous Model ◽

Discrete Models ◽

Convex Programming Problem ◽

Algebraic Equations ◽

Constant Mass ◽

Electrical Power System

Using thermal inertia in district heating systems (DHSs) to improve the dispatch flexibility and economy of integrated heat and electricity systems (IHESs) is a research hotspot and difficulty. In most existing studies, the partial differential equations (PDEs) of thermal inertia are approximated by discrete-time models, making it difficult to accurately describe the continuous dynamic processes. In this paper, we propose a novel generalized phasor method (GPM) for thermal inertia in DHSs with constant mass flow. Based on the analytical solution of the PDEs and the Fourier transform, the intractable PDEs are transformed into a series of complex algebraic equations represented by phasors. The GPM has higher accuracy compared to traditional discrete models because it is essentially a continuous model in the time domain. Then, we present a different representation of an integrated heat and electricity dispatch (IHED) model combining a DHS model in phasor form and a traditional electrical power system model. The IHED model is a convex programming problem and can be easily solved. The effectiveness of the proposed GPM and dispatch model is verified in three test systems. Compared with traditional methods for modeling the thermal inertia, the proposed GPM is more accurate.

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The Impact of Modified EU ETS Allocation Principles on the Economics of CHP-Based District Heating Networks

SSRN Electronic Journal ◽

10.2139/ssrn.1783560 ◽

2011 ◽

Cited By ~ 74

Author(s):

Günther Westner ◽

Reinhard Madlener

Keyword(s):

District Heating ◽

Eu Ets ◽

The Impact ◽

Heating Networks

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RELaTED Project: New Developments on Ultra-Low Temperature District Heating Networks

Proceedings ◽

10.3390/proceedings2020065008 ◽

2020 ◽

Vol 65 (1) ◽

pp. 25

Author(s):

Antonio Garrido Marijuan ◽

Roberto Garay ◽

Mikel Lumbreras ◽

Víctor Sánchez ◽

Olga Macias ◽

...

Keyword(s):

Low Temperature ◽

High Performance ◽

Waste Heat ◽

District Heating ◽

Hot Water ◽

Thermal Systems ◽

Heating Source ◽

Wide Range ◽

Thermal Sources ◽

Heating Networks

District heating networks deliver around 13% of the heating energy in the EU, being considered as a key element of the progressive decarbonization of Europe. The H2020 REnewable Low TEmperature District project (RELaTED) seeks to contribute to the energy decarbonization of these infrastructures through the development and demonstration of the following concepts: reduction in network temperature down to 50 °C, integration of renewable energies and waste heat sources with a novel substation concept, and improvement on building-integrated solar thermal systems. The coupling of renewable thermal sources with ultra-low temperature district heating (DH) allows for a bidirectional energy flow, using the DH as both thermal storage in periods of production surplus and a back-up heating source during consumption peaks. The ultra-low temperature enables the integration of a wide range of energy sources such as waste heat from industry. Furthermore, RELaTED also develops concepts concerning district heating-connected reversible heat pump systems that allow to reach adequate thermal levels for domestic hot water as well as the use of the network for district cooling with high performance. These developments will be demonstrated in four locations: Estonia, Serbia, Denmark, and Spain.

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State estimation models of district heating networks for integrated energy system considering incomplete measurements

Applied Energy ◽

10.1016/j.apenergy.2020.116105 ◽

2021 ◽

Vol 282 ◽

pp. 116105

Author(s):

Suhan Zhang ◽

Wei Gu ◽

Haifeng Qiu ◽

Shuai Yao ◽

Guangsheng Pan ◽

...

Keyword(s):

State Estimation ◽

District Heating ◽

Energy System ◽

Integrated Energy System ◽

Heating Networks ◽

Estimation Models

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Reliability segment design in single-source district heating networks based on valve network models

Sustainable Cities and Society ◽

10.1016/j.scs.2020.102463 ◽

2020 ◽

Vol 63 ◽

pp. 102463

Author(s):

Ding Mao ◽

Peng Wang ◽

Wei Wang ◽

Long Ni

Keyword(s):

District Heating ◽

Network Models ◽

Single Source ◽

Heating Networks

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Method for Redesign of District Heating Networks within Transition from the 2nd to the 3rd Generation

Applied Mechanics and Materials ◽

10.4028/www.scientific.net/amm.657.689 ◽

2014 ◽

Vol 657 ◽

pp. 689-693

Author(s):

Răzvan Corneliu Lefter ◽

Daniela Popescu ◽

Alexandrina Untăroiu

Keyword(s):

District Heating ◽

Design Stage ◽

Heating Systems ◽

Load Duration ◽

Load Duration Curve ◽

District Heating Systems ◽

Consumption Rates ◽

Heat Loads ◽

Heating Networks

Important investmentsare made lately in the area of district heating, as a technology capable ofhelping countries to reach sustainability goals. In Romania, European fundswere spent for transition from the 2nd to the 3rdgeneration of district heating systems. The lack of appropriate monitoringsystems in old district heating systems makes optimisation nowadays very difficult,especially because nominal values used in the first design stage areoverestimated. Realistic nominal heat loads are necessary to make goodestimations of hydraulic parameters to be used for redesign. This studyproposes a method that uses the heat load duration curve theory to identify theappropriate nominal heat loads to be used for redesign. Comparison betweenresults obtained by applying the nominal heat loads of each consumer, as theywere established in the first design stage, and the ones identified by theproposed method are analyzed in a case study. The results show that errors arein the +/- 3% band, between the metered heat consumption rates and the proposedrates. The new method can be used for the sizing of pumps and district heatingnetworks after retrofit, in order to get better adjustments of the circulationpumps and increase of the energy efficiency.

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