Electric Power

Status Quo and Prospect of Multi-source Heterogeneous Data Fusion Technology for New Power System

WANG Zhen, LIU Dong, XU Chongyou, WENG Jiaming, CHEN Fei

2023, 56(4): 1-15. DOI: 10.11930/j.issn.1004-9649.202211077

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In the context of energy transition, the new power system is being built continuously with the goal of being clean and low-carbon, open and interactive. With the fast development of monitoring technology and communication technology, the data sources of power system have become more diverse and the structures of the data have become more complex, which provides a data basis for and at same time brings new challenges to the new power system data fusion. Firstly, the data characteristics of the new power system are analyzed and the data fusion requirements of the new power system are proposed. Then the data model of the new power system and the hierarchical division of multi-source heterogeneous data fusion technologies are introduced, and the advantages and limitations of the key fusion technologies and their applicable scenarios are analyzed. The data requirements, data sources, fusion objectives, common methods and research difficulties of multi-source heterogeneous data fusion technologies are summarized under five typical scenarios, including transmission and distribution collaboration, source-grid-load-storage collaboration, virtual power plants, multi-type loads, and electricity-carbon trading. Finally, the future prospects of the new power system data fusion technology are explored.

A Hybrid HVDC Topology Suitable for Large-Scale Pure Clean Energy Power Base Transmission

XU Wenzhe, ZHANG Zheren, XU Zheng

2023, 56(4): 17-27. DOI: 10.11930/j.issn.1004-9649.202205044

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In order to meet the transmission needs of large-scale pure new energy power bases, after topology comparison, this paper used a hybrid cascaded topology consisting of a line commutated converter (LCC) and a modular multilevel converter (MMC) in the sending end and a hybrid high voltage direct current (HVDC) scheme featuring a diode-MMC (D-MMC) topology in the receiving end. Specifically, the rectifier station MMC provides the alternating current (AC) voltage support at the sending end and cooperates with the LCC as a sending power to balance transfer stations. Then the basic control and fault ride-through strategy of the system is designed so that the system can stably send out new energy power and has both economy and fault ride-through capability. Finally, a ±800 kV/5000 MW bipolar direct current (DC) transmission simulation model is built in PSCAD/EMTDC to verify the effectiveness of the proposed control and fault ride-through strategy, and the results indicate that the selected topology is suitable for transmission scenarios of large-scale pure new energy power bases.

Study on Overvoltage of Wind Farm Under AC Fault at Sending End of HVDC Transmission System

LIANG Wei, WU Linlin, LAI Qiping, LI Dongsheng, XU Man, SHEN Chen

2023, 56(4): 28-37. DOI: 10.11930/j.issn.1004-9649.202212099

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When the short circuit ratio of receiving end AC system is small, the fault disturbance of sending end AC system may cause commutation failure of the inverter and overvoltage at the LCC-HVDC sending end AC bus. This paper studies the mechanism and influencing factors of overvoltage at the point of common connection (PCC) of the wind farm caused by an AC fault at the HVDC sending end. Firstly, an electromagnetic transient model is established for UHVDC wind power transmission system. Secondly, the influence mechanism of the wind farm and HVDC dynamic characteristics on the transient voltage at the PCC of wind farm under different sending end faults is analyzed. Then, the factors affecting the transient voltage variation at the PCC of the wind farm are analyzed and verified by simulation. The results show that the variation of transient voltage at the PCC of the wind farm is mainly affected by the AC bus voltage of the rectifier station and the power response characteristics of the wind farm. In addition, it is found that the influence characteristics of wind farm capacity, wind speed, and other factors on the voltage at the PCC of wind farm are different under single change and different combinations.

Impedance Modeling Method of Offshore Wind Farm Integration Through MMC-HVDC With MMC Circulation Control

YANG Shuting, CHEN Xin, HUANG Tong, WEI Qixuan

2023, 56(4): 38-45. DOI: 10.11930/j.issn.1004-9649.202207084

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Based on impedance analysis, this paper focuses on the circulation control of a modular multilevel converter (MMC) and conducts in-depth research on the stability impact of offshore wind farm integration based on a permanent magnetic synchronous generator (PMSG) through the MMC-HVDC system. Firstly, the impedance model of a flexible MMC-HVDC converter station and an offshore wind farm is built by harmonic linearization, and then the impedance model of PMSG-based wind farm integration through the MMC-HVDC system considering the frequency coupling effect is derived. Secondly, based on the impedance-based stability criterion, the influence of circulation control on MMC impedance and the MMC-HVDC system’s stability is revealed, and then an MMC impedance remodeling control based on the circulation link is proposed. Finally, the stability analysis and the impedance modeling method are verified by RT-LAB hardware in the loop real-time simulation system.

Intelligent Identification Method of Wind Farm Sub-synchronous/Super-synchronous Oscillation Parameters Based on RA-CNN and Synchrophasor

LU Youwen, CUI Hao, CHEN Jianing, PENG Xiangjia, FENG Shuang, LIU Dong

2023, 56(4): 46-55,67. DOI: 10.11930/j.issn.1004-9649.202208068

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In recent years, the proportion of wind power connected to the grid has increased significantly, and the probability of occurrence of sub-synchronous/super-synchronous oscillations caused by this has also been greatly raised, which seriously threatens the safety and steadiness of the system. Accurate identification of sub-synchronous/super-synchronous oscillation parameters is the basis for oscillation suppression. Therefore, this paper proposes an identification method based on the attention mechanism of the residual convolutional neural network (CNN). The local correlation and weight sharing of the convolutional neural network determine its stronger feature learning and expression ability, and thus, the oscillation parameters can be more accurately identified when it is combined with the attention mechanism. Meanwhile, this method introduces residual connections to solve the problems of gradient vanishing and network degradation in the deep convolutional neural network. Simulations indicate that compared with the traditional method, this method can completely identify the parameters of sub-synchronous/super-synchronous oscillations on the data of a short time window. In addition, it can avoid the identification error caused by the subjective factors of the traditional method and reduce the complexity of oscillation parameter identification.

Inhibition of Subsynchronous Oscillation of Direct-Drive Wind Turbine by Improved LADRC in Weak Grids

LI Bohao, GUO Kunli, LV Jiajun, CAI Weizheng, LIU Luhao, LIU Fengyi, HAO Yifan

2023, 56(4): 56-67. DOI: 10.11930/j.issn.1004-9649.202206135

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As the direct-drive wind turbine generator system (WTGS) causes subsynchronous oscillation (SSO) in weak grids, this paper proposes the differential feed-forward linear active disturbance rejection control (LADRC) based on the first-order total disturbance deviation control. It uses the fully improved LADRC strategy to suppress the SSO phenomenon (here, “fully” indicates that the outer loop of voltage, the inner loop of current, and the phase-locked loop (PLL) are all controlled accordingly). Firstly, the mathematical model for the grid connection of the direct-drive WTGS is built. Secondly, the improved LADRC is designed, and its characteristics are analyzed in combination with the grid-connected system of WTGS. The analysis shows that the improved control not only reduces the tracking error of the system but also has stronger anti-interference performance compared with the traditional LADRC. Finally, the proposed strategy is compared with the fully proportional-integral (PI) control and all-traditional LADRC by simulation software PSCAD/EMTDC. The results indicate that compared with the traditional LADRC, the proposed method reduces the overshoot by 1.62% while shortening the system regulation time by 0.129 s, which can effectively suppress the SSO phenomenon and have good adaptability.

Inertia Optimization Control Model of AC/DC Sending-End System Based on Multi-source Energy Storage Coordination

XIANG Song, SU Peng, WU Jian, LIU Xin, MA Jitao

2023, 56(4): 68-76. DOI: 10.11930/j.issn.1004-9649.202205065

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To address the low inertia level of AC/DC sending-end systems with high-proportion new energy access, this paper proposes an optimal control method for the inertia of such systems based on multi-source energy storage coordination. First, considering that large-scale new energy access will affect the energy balance of sending-end systems, the paper establishes a power flow equation for AC/DC sending-end systems with a high proportion of wind power. Second, in response to the insufficient inertia support of weak sending-end systems, it puts forward a multi-source energy storage system with electricity, heat, and gas energy conversion and storage equipment and analyzes the system inertia support characteristics under the coordination of multi-source energy storage. On this basis, considering the frequency stability of sending-end systems, an inertia optimization control model is built for AC/DC sending-end systems based on multi-source energy storage coordination. Finally, an AC/DC sending-end system in an area in northern China is used as a simulation example to verify the effectiveness of the proposed model. The model can provide a theoretical basis for the inertia stability control of AC/DC hybrid systems containing large-scale new energy and realize the safe and stable operation of AC/DC sending-end systems.

Reactive Voltage Emergency Control Strategy of Wind-Thermal-Bundled DC Transmission System Considering Wind Farm Regulation Margin

ZHOU Wenjun, CAO Yi, LI Jie, JIN Tao, CHEN Wenjian, ZHOU Xia

2023, 56(4): 77-87. DOI: 10.11930/j.issn.1004-9649.202211016

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In order to suppress the transient overvoltage of direct current (DC) sending-end power grid and make full use of wind power in the power regulation of wind-thermal-bundled DC transmission system, a reactive voltage emergency control strategy considering wind farm regulation margin is proposed. Firstly, the change in the electrical quantity of the wind-thermal-bundled system under commutation failure and the overvoltage mechanism of the DC sending end caused by the failure are analyzed. Secondly, after the commutation failure, the continuous commutation failure of the DC system is suppressed by reducing the DC transmission power. Therefore, the reactive power demand of the system during the fault recovery period is reduced, and the reactive power flow change in the system after the power drop is analyzed. Thirdly, the reactive voltage emergency control strategy of the DC sending end is proposed for the transient high voltage of the sending end caused by surplus reactive power. The reactive power margin of the wind farm is allocated according to the ultra-short-term predicted wind speed, and the wind turbine controller with multiple working modes is designed for different situations. Finally, the simulation results show that the proposed control method can better solve the transient overvoltage problem at the DC sending end of the wind-thermal-bundled DC transmission system.

Power Terminal Lightweight Authentication Protocol for Edge Computing

YANG Jinxiang, PENG Yonggang, CAI Tiantian, XI Wei, DENG Qingtang

2023, 56(4): 88-94. DOI: 10.11930/j.issn.1004-9649.202204082

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Edge computing effectively relieves the computing pressure of cloud platform and reduces the consumption of network transmission bandwidth, but it brings new security problems as well, the traditional authentication mechanism no longer applies to “cloud-edge-end” network architecture. We proposed a lightweight two-way authentication protocol based on cloud-edge collaboration. In view of the limited resources of massive power terminal, the protocol is only based on a Hash and XOR operation to achieve certification, so it reduces the pressure of terminal calculation and transmission bandwidth. Its security was successfully verified by AVISPA tool together with informal analysis. The analysis and simulation results show that the protocol can resist replay attack, impersonation attack and so on. In addition, the comparison with similar protocols shows that the protocol has less computation and communication overhead.

Third-Party Entity Voltage Regulation Ancillary Service Compensation and Procurement in Distribution Networks with High-Penetration PV

BAI Jing, JIN Guanghou, SUN Helin, HU Chufan, ZHAO Jinquan, CHEN Tianhua

2023, 56(4): 95-103,111. DOI: 10.11930/j.issn.1004-9649.202211037

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The large-scale grid connection of distributed photovoltaics brings many voltage problems. Demand responses can bring flexible voltage regulation ability to solve problem of photovoltaics curtailments. Under the background of building the new type power market mechanism, a strategy for third-party entity voltage regulation ancillary service procurement in distribution networks with high-penetration PV is proposed. Based on the analysis of the compensation range of third-party entity, the computation method of the compensation mechanism of third-party entity voltage regulation ancillary service is discussed. For the scenario of high penetration PV induced voltage regulation difficulty, we suggest the photovoltaic power generation companies share the compensations of voltage regulation ancillary service. Considering fully regulation ability of grid side reactive power equipment, an optimization model for third-party entity voltage regulation ancillary service procurement in distribution networks is established, which the goal is to minimize the costs of photovoltaics curtailment and the compensations of voltage regulation ancillary service. An example shows that the strategy proposed in this paper can maintain the safe operation of the distribution network while taking into account the benefits of the photovoltaic power companies and the third-party entities, and achieve a win-win situation for all parties.

Switching Technology of Three-Terminals Soft Open Point Control Mode

WANG Hui, CAO Yi, LUO Ning, GAO Hua, ZHANG Yan, ZHANG Yu, CHENG Haozhong

2023, 56(4): 104-111. DOI: 10.11930/j.issn.1004-9649.202203028

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This paper proposes a three-terminals soft open point (SOP) operation control mode switching technology under the multi-feeder faults. Firstly, combined with the inner and outer loop structures of control mode of three-terminals SOP, a control mode switching strategy with improved control logic is proposed. Secondly, in order to realize the smooth transition between SOP working modes under multiple feeder faults, a control mode switching process suitable for three-terminals SOP under multiple feeder faults is proposed. Then, by adopting the phase angle pre-synchronization strategy, the smoothness of the phase angle when the power-loss feeder is connected to the grid is ensured. Thirdly, the phase angle pre-synchronization strategy is adopted to ensure the smoothness of the phase angle when the power-loss feeder is connected to the grid. Finally, A power distribution system model with three-terminals SOP is built for simulation. The simulation results show that the proposed operation control mode switching technology can reduce the maximum voltage fluctuation on the DC side, and the voltage and phase angle of each port can transition smoothly.

Research on Transformer Noise Suppression Based on Redundant Convolutional Encoder Decoder

XIN Quanjin, LI Xiaohua, YANG Yi, LI Juncong, XIA Nenghong

2023, 56(4): 112-118. DOI: 10.11930/j.issn.1004-9649.202203065

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The acoustic signal generated during the operation of the transformer is an important basis for evaluating the operation status of the transformer and the noise level of the substation. A transformer noise suppression method based on redundant convolutional codec (RCED) network is proposed. The time-frequency characteristics of clean acoustic signal and noisy signal are obtained by using short-time Fourier transform, and the noise reduction model of transformer acoustic signal is constructed. The noise signal of converter transformer in a converter station is tested and verified. The results show that the proposed model has good noise reduction effect, and the proposed method has reference significance for the online monitoring system of transformer voiceprint vibration and the accurate detection of substation noise.

Droop Control Based Auxiliary Power Compensation for Power Systems with Flexible DC Transmission

LIN jinjiao, KONG Xiangping, WANG Chuyang, ZHANG Qiuyue, ZHENG Junchao, ZHANG Li

2023, 56(4): 119-129. DOI: 10.11930/j.issn.1004-9649.202203039

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At present, the droop control strategy is widely used in modularized multilevel converter stations in multi-terminal flexible DC interconnection system, and the voltage and active power can be adjusted autonomously according to the droop characteristic curve. However, this strategy can barely handle the abnormal DC side voltage fluctuation caused by power flow reversal and outage of the converter station. Therefore, the linear model of converter station based on droop control strategy is firstly established in this paper, which shows that droop control increases the difficulty of meeting the demand of emergent conditions. On this basis, an improved droop control strategy based on auxiliary power compensation was proposed to solve the problem of DC side voltage mutation under emergent conditions. Compared with traditional droop control, this strategy does not need to change the control parameters of converter station. The reaction speed is faster, indicating stronger voltage fluctuation suppression capability. Meanwhile, the performance of the DC interconnection system to cope with sudden working conditions is optimized. Simulation results verify the effectiveness of the proposed control strategy.

Bi-objective Rolling Operation Optimization Based on Surrogate Model Acceleratiy of Community-Level Integrated Energy Systems

HU Xiaoman, TIAN Weikun, SONG Guanyu, YU Hao

2023, 56(4): 130-137,145. DOI: 10.11930/j.issn.1004-9649.202205056

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Uncertainties in community-level integrated energy systems (CIESs) have been increasing due to the high penetration of distributed generation. Besides, the economic and environmental operation of CIESs should be considered at the same time, making its optimal operation problem a typical bi-objective one. In this paper, a bi-objective rolling scheduling method for CIES is proposed, based on the triangle splitting searching algorithm. Firstly, the surrogate model is employed to explore the feasible region. Then the surrogate model accelerated bi-objective optimization method is applied in the framework of model predictive control (MPC), in which the operation strategy is optimized according to the updated forecasting information. Finally, the proposed method is verified by a case study of a practical CIES to demonstrate its effectiveness and feasibility.

Optimal Operation of Multiple Integrated Energy Systems Considering Power and Heat Interaction and Shared Energy Storage System

GUO Yanxiu, SU Jianjun, LIU Yang, YUAN Shuangchen

2023, 56(4): 138-145. DOI: 10.11930/j.issn.1004-9649.202203053

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With the technological development of integrated energy systems (IES) and the popularity of the shared energy storage system (SESS), the multiple integrated energy systems (MIES) would be gradually formed by several IESs and their interactions. The optimal operation of MIES with power and heat interaction considering SESS, optimization for equipment output in IES and adjustment for energy exchange among IES can reduce the operation cost of the whole MIES. Firstly, the optimal operation model for MIES considering the electricity and heat interaction is proposed on the basis of common equipment output of IES and SESS, where the electricity and heat interaction among each IES in MIES and external grid. Secondly, the model is solved by mixed integer linear programming method. In the numerical test, MIES consisting of three IES are taken as an example to analyze the economy of MIES which are connected to SESS considering power and heat interaction.

Optimal Scheduling of Integrated Energy System Considering Uncertainty of Heat Medium Flow Rate and Heating Network Loss

ZHANG Tao, LIU Kang, TAO Ran, WANG Qingchuan, HUANG Mingjuan

2023, 56(4): 146-155. DOI: 10.11930/j.issn.1004-9649.202204087

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Aiming at the coupling of multiple energy sources and the heterogeneity of different energy sources in integrated energy system, a more accurate approximate heating pipeline model is firstly constructed using flow segmentation method, and combined with the heat storage characteristics of buildings, a thermal system model is jointly constructed with consideration of two types of thermal inertia; secondly, the characteristics of thermal energy in the scheduling process are studied, and two types of uncertain quantities are described; and then, a robust optimization model and an opportunistic optimization model are established using the information gap decision theory (IGDT) method, and the NSGA-II algorithm is introduced to solve the multi-objective model; finally, the simulation results of a 44-node heating network system show that the proposed method can effectively quantify the influence of uncertainty of heat medium flow rate and heat loss on scheduling operation, and improve the economy of system operation.

Robust Optimal Configuration Planning of Integrated Energy System for Return on Investment

LIANG Tao, YIN Xiaodong, LIU Yaxiang

2023, 56(4): 156-166. DOI: 10.11930/j.issn.1004-9649.202205043

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Reasonable optimization of integrated energy system (IES) capacity configuration is the basis for improving returns on investment and realizing efficient energy utilization. Aiming at the uncertainty influences of wind and photovoltaic power output and energy-using load on both cost and revenue, a robust optimal configuration method for return on investment is presented. Firstly, an IES optimal configuration model is built to maximize the internal rate of return, with consideration of the constraints of investment capacity, equipment operation, energy balance and internal and external network interaction. Then, by introducing the information gap decision theory (IGDT) to deal with the uncertainties of both source and load in IES, a robust optimization model for return on investment is constructed, and the complexity of the model is reduced through equivalent transformation and dual transform. A decomposition solution strategy is proposed to obtain the maximum fluctuation range of uncertain parameters and the corresponding optimal configuration scheme in the premise of meeting the expected return on investment. Finally, an actual IES is taken for case study, and the results show that the proposed method is more effective and practical than the traditional configuration methods in increasing the return on investment and improving the robustness of optimal configuration.

Miniaturized Multi-band Compound Antenna for Detecting Partial Discharge in GIS

FENG Yang, ZHOU Lei, MA Quanfu, YIN Song, WANG Shuo

2023, 56(4): 167-174. DOI: 10.11930/j.issn.1004-9649.202103071

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In order to detect the UHF signal of partial discharge (PD) in gas insulated switchgear (GIS), a multi-frequency point broadband compound antenna was designed for detecting PD in GIS. Firstly, the principle of miniaturization and broadbandization of the compound antenna was analyzed to realize the miniaturization of the antenna. Then the voltage standing wave ratio (VSWR) of the antenna was tested by vector network analyzer. Finally, a GIS partial discharge test system was built in the laboratory to conduct the actual measurement study on the antenna. The test results show that the compound antenna has the characteristics of multi-band, miniaturization and high gain; it has a VSWR of less than 2 with a wide frequency range and can record most of the partial discharge information in the frequency range of 0.75 GHz to 0.90 GHz, 1.23 GHz to 1.48 GHz, 1.78 GHz to 2.12 GHz and 2.42 GHz to 2.79 GHz. with the increase of frequency, the antenna’s gain gradually increases with a maximum gain reaching up to 6.5 dB, which can effectively receive weak UHF signals. It is concluded that the designed antenna has a good performance and is quite promising for PD on-line detection applications.

Distribution Characteristics of Partial Discharge Radio Frequency Signal in Transformer Tank and Bushing

HUANG Hui, YANG Zhihao, WEI Jianguo, DENG Hui, LIU Yi

2023, 56(4): 175-183. DOI: 10.11930/j.issn.1004-9649.202209032

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The external partial discharge (PD) radio frequency (RF) detection method is suitable for equipment in operation, and has become one of the important means to perceive the insulation defects of transformer and bushing. The detection sensitivity is affected by the matching of sensor installation position and polarization direction. In order to improve the sensitivity of the external RF detection method, this paper studies the amplitude distribution characteristics of the RF signal when the partial discharge electromagnetic wave in the transformer tank propagates through the bushing to the external space. Firstly, the propagation simulation model of partial discharge electromagnetic wave under bushing is established. Secondly, the dynamic process of electromagnetic wave propagation is shown by chromaticity diagram. Thirdly, the electric field intensity waveform of RF signal and the polarization direction of electric field intensity at typical locations outside the bushing are analyzed. Finally, partial discharge test and RF signal measurement are carried out, and the amplitude distribution characteristics and polarization characteristics of RF signal are verified by the measurement results of biconical antenna. The simulation results show that the electromagnetic wave propagates outward with the bushing grounding flange and the bushing top as the center; strong RF signals are measured near the two positions using the biconical antenna; the measured RF signal is the strongest when the polarization direction of the biconical antenna is parallel to the axial direction of the bushing. This conclusion is significant for improving the sensitivity of transformer and bushing partial discharge radio frequency detection.

An Active Ground Fault Location Method for Low-Voltage DC Lines Based on DFFT

CAO Fulu, ZHAO Jinbin, PAN Chao, MAO Ling, QU Keqing

2023, 56(4): 184-191. DOI: 10.11930/j.issn.1004-9649.202211032

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For the problem of locating ground faults in low-voltage DC cable lines containing power electronic transformers, a single-ended volume fault location method using power electronic transformers with active injection is proposed for rapid fault detection and restoration of power supply. A sinusoidal voltage signal with 210 Hz frequency is injected into the low voltage side through the medium voltage port of the power electronic transformer. The characteristic signal will be transmitted to the low voltage side capacitor through the high frequency transformer, and the characteristic parameters of the capacitor voltage and current are extracted and identified using the fast Fourier transform to calculate the line impedance after the fault. At the same time, a secondary curve fitting construction curve method is used to reduce the impedance errors caused by spectral leakage and frequency domain reactance waveform oscillation and to obtain the accurate fault location. Finally, the PSCAD/EMTDC simulation results have verified the effectiveness of the proposed method for locating the ground faults of low-voltage DC lines containing power electronic transformers with noise interference resistance and certain transition resistance resistance.

Comparative Study of Thermoelectric Characteristics of Two Flexibility Transformation Technologies

LI Xiangyong, WU Xin, PANG Chunfeng, LIU Shuangbai, MEI Long, SI Paiyou

2023, 56(4): 192-200. DOI: 10.11930/j.issn.1004-9649.202206068

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High and low pressure bypass combined heating supply and low-pressure cylinder zero output technology are two important flexibility transformation technologies, which can effectively improve thermal power units’ peak regulation capacity and heating capacity. In this paper, for the two same model 350 MW supercritical units of North China power grid, a therma lsystem simulating software named Ebsilon is used to build the high and low pressure bypass combined heating supply and low-pressure cylinder zero output model, whose reliability are demonstrated by actual field performance tests. The models’ full operation interval calculation results show that：the high and low pressure bypass combined heating supply model has better thermoelectric decoupling capacity because of it's maximum heating load capacity is 57.27 MW more and minimum electrical load capacity is 141.04 MW less than the low-pressure cylinder zero output model; The low-pressure cylinder zero-output model has a higher energy utilization rate because of its’ electrical load is 61.012 MW higher than high and low pressure bypass combined heating supply model when they have the same main steam and heating steam. Under the existing peak regulation revenue mechanism of North China Power Grid, the low-pressure cylinder zero-output heating can obtain a higher maximum comprehensive income when the main steam flow is less than 505 t/h; the two technologies can obtain the same max comprehensive benefit when the main steam flow is 505 t/h; the high and low pressure bypass combined heating supply model can obtain higher maximum comprehensive revenue when the main steam flow rate is greater than 505 t/h.

Operation Optimization of Combined Heat and Power Units Based on Energy Consumption, Economy and Carbon Emission

REN Xin, WANG Du, JIN Yafei, WANG Zhigang

2023, 56(4): 201-210. DOI: 10.11930/j.issn.1004-9649.202211071

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A multi-objective optimization model for combined heat and power units is established to address the problem of difficulty in balancing energy consumption, economy and low carbon in the operation of the combined heat and power units. Firstly, combining with the power peaking auxiliary market and carbon emission trading market, and taking the efficiency, profit and carbon emission rate as the objective functions, the multi-objective particle swarm algorithm is used to find the best power generation power considering the constraints related to the unit operation. Then, the multi-objective decision making is performed by using the information entropy weight method combined with the technique for order preference by similarity to an ideal solution. Finally, it is verified by the unit simulation model. The results show that the optimized optimal power generation is 115.1, 89.5 and 89.1 MW for 20, 100 and 180 t/h steam supply, respectively, and the optimized operation scheme significantly reduces the carbon emission and takes into account the energy consumption, economy and low carbon performance of the unit.

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