50 research outputs found
Coordinated day-ahead reactive power dispatch in distribution network based on real power forecast errors
Reactive power outputs of DGs are used along with capacitor banks to regulate distribution network voltage. However, reactive power capability of a DG is limited by the inverter ratings and real power outputs of the DG. In order to achieve optimal power flow, minimize power losses, and minimize switching of capacitor banks, a day-ahead coordinated dispatch method of reactive power is proposed. Forecast errors of DG real power in every period are used to estimate the probability distribution of DGs reactive power capacity. Considering different output characteristics and constraints of reactive power sources, a dynamic preliminary-coarse-fine adjustment method is designed to optimize DG and shunt compensator outputs, decrease the switching cost, and reduce loss. The preliminary optimization obtains initial values, and multiple iterations between the coarse and fine optimizations are used to achieve a coordinated result. Simulations studies are performed to verify the proposed method
SAR2EO: A High-resolution Image Translation Framework with Denoising Enhancement
Synthetic Aperture Radar (SAR) to electro-optical (EO) image translation is a
fundamental task in remote sensing that can enrich the dataset by fusing
information from different sources. Recently, many methods have been proposed
to tackle this task, but they are still difficult to complete the conversion
from low-resolution images to high-resolution images. Thus, we propose a
framework, SAR2EO, aiming at addressing this challenge. Firstly, to generate
high-quality EO images, we adopt the coarse-to-fine generator, multi-scale
discriminators, and improved adversarial loss in the pix2pixHD model to
increase the synthesis quality. Secondly, we introduce a denoising module to
remove the noise in SAR images, which helps to suppress the noise while
preserving the structural information of the images. To validate the
effectiveness of the proposed framework, we conduct experiments on the dataset
of the Multi-modal Aerial View Imagery Challenge (MAVIC), which consists of
large-scale SAR and EO image pairs. The experimental results demonstrate the
superiority of our proposed framework, and we win the first place in the MAVIC
held in CVPR PBVS 2023
Potential of Core-Collapse Supernova Neutrino Detection at JUNO
JUNO is an underground neutrino observatory under construction in Jiangmen, China. It uses 20kton liquid scintillator as target, which enables it to detect supernova burst neutrinos of a large statistics for the next galactic core-collapse supernova (CCSN) and also pre-supernova neutrinos from the nearby CCSN progenitors. All flavors of supernova burst neutrinos can be detected by JUNO via several interaction channels, including inverse beta decay, elastic scattering on electron and proton, interactions on C12 nuclei, etc. This retains the possibility for JUNO to reconstruct the energy spectra of supernova burst neutrinos of all flavors. The real time monitoring systems based on FPGA and DAQ are under development in JUNO, which allow prompt alert and trigger-less data acquisition of CCSN events. The alert performances of both monitoring systems have been thoroughly studied using simulations. Moreover, once a CCSN is tagged, the system can give fast characterizations, such as directionality and light curve
Detection of the Diffuse Supernova Neutrino Background with JUNO
As an underground multi-purpose neutrino detector with 20 kton liquid scintillator, Jiangmen Underground Neutrino Observatory (JUNO) is competitive with and complementary to the water-Cherenkov detectors on the search for the diffuse supernova neutrino background (DSNB). Typical supernova models predict 2-4 events per year within the optimal observation window in the JUNO detector. The dominant background is from the neutral-current (NC) interaction of atmospheric neutrinos with 12C nuclei, which surpasses the DSNB by more than one order of magnitude. We evaluated the systematic uncertainty of NC background from the spread of a variety of data-driven models and further developed a method to determine NC background within 15\% with {\it{in}} {\it{situ}} measurements after ten years of running. Besides, the NC-like backgrounds can be effectively suppressed by the intrinsic pulse-shape discrimination (PSD) capabilities of liquid scintillators. In this talk, I will present in detail the improvements on NC background uncertainty evaluation, PSD discriminator development, and finally, the potential of DSNB sensitivity in JUNO
Day-Ahead Active Power Scheduling in Active Distribution Network Considering Renewable Energy Generation Forecast Errors
With large-scale integration of distributed energy resources (DERs), distribution networks have turned into active distribution networks (ADNs). However, management risks and obstacles are caused by this in due to renewable energy generation (REG) forecasting errors. In this paper, a day-ahead active power scheduling method considering REG forecast errors is proposed to eliminate the risks, minimize the costs of distribution companies and achieve optimal power flow. A hierarchical coordination optimization model based on chance constrained programming is established to realize day-ahead optimal scheduling of active power in ADNs coordinated with network reconfiguration, achieving an optimal solution of network topologies and DER outputs. The hierarchical method includes three levels: the first level provides initial values, and multiple iterations between the second and third level are used to solve the multi-period mixed integer nonlinear optimization problem. The randomness due to REG forecast errors is tackled with chance constrained programming in the scheduling procedure. The hybrid particle swarm optimization algorithm is employed to solve the proposed model. Simulation results verify the validity of the proposed method with an improved 33 nodes distribution network
Participation of Load Resources in Day-Ahead Market to Provide Primary-Frequency Response Reserve
Day-Ahead Active Power Scheduling in Active Distribution Network Considering Renewable Energy Generation Forecast Errors
With large-scale integration of distributed energy resources (DERs), distribution networks have turned into active distribution networks (ADNs). However, management risks and obstacles are caused by this in due to renewable energy generation (REG) forecasting errors. In this paper, a day-ahead active power scheduling method considering REG forecast errors is proposed to eliminate the risks, minimize the costs of distribution companies and achieve optimal power flow. A hierarchical coordination optimization model based on chance constrained programming is established to realize day-ahead optimal scheduling of active power in ADNs coordinated with network reconfiguration, achieving an optimal solution of network topologies and DER outputs. The hierarchical method includes three levels: the first level provides initial values, and multiple iterations between the second and third level are used to solve the multi-period mixed integer nonlinear optimization problem. The randomness due to REG forecast errors is tackled with chance constrained programming in the scheduling procedure. The hybrid particle swarm optimization algorithm is employed to solve the proposed model. Simulation results verify the validity of the proposed method with an improved 33 nodes distribution network
Multi-stage coordination optimisation control in hybrid AC/DC distribution network with high-penetration renewables based on SOP and VSC
Power electronic devices such as soft open point (SOP) and voltage source converter (VSC) begin to be applied to distribution networks, which are developed into hybrid AC/DC distribution networks. Both power electronic equipment and conventional control devices, such as tie switches, coexist in a hybrid AC/DC distribution network, and the coordination optimisation of these control devices can eliminate the risks caused by high-penetration renewable energy generation (REG) integration. Here, the structure of the hybrid AC/DC distribution networks with SOP and VSC is analysed. A multi-stage coordination control method is proposed, including day-ahead stage, inner-day stage, and real-time stage. In the day-ahead stage, a sequential coordination optimisation model considering network reconfiguration by switches is established; in the inner-day stage, a loop-locked rolling optimisation control model based on model predictive control is built, to reduce the influence of the REG randomness output; in the real-time stage, voltage deviations are minimised in risk scenarios by regulating powers of SOP and VSC. Mixed-integer second-order cone programming algorithm is adopted to realise the coordination optimisation of SOP, VSC, and tie switch. The results show that the proposed method can increase REG penetrations and improve voltage quality and economic benefit of the hybrid AC/DC distribution network