Research on the Cross-Platform Co-Simulation Strategy of Power Systems Based on the Model-Segmentation Algorithm

In recent years, cross-platform co-simulation has become an important development direction of the real-time simulation of power systems. Model segmentation is at the core of the realization of cross-platform joint simulation and parallel real-time simulation of these systems. In essence, it is based on the deep application of a system-decoupling algorithm. In order to solve problems that a single interface cannot, it considers the data interaction of large- and small-step systems at the same time This paper proposes an improved joint-simulation strategy based on the model-segmentation method for the cross-platform joint-simulation technology of a large-scale, flexible direct-power grid sent by the wind farms of RT-lab and Hypersim. Firstly, by studying several common interface algorithms in the current project, the adaptability of different interface algorithms is analyzed. Secondly, the problem of high-frequency oscillation caused by the inductance-decoupling algorithm is improved, and an improved segmentation-model algorithm is proposed. Finally, according to the adaptability, each interface algorithm is applied to the wind-power-based, flexible direct-transmission, dual-platform simulation model that was built for this study. The simulation results verify the feasibility of the improved interface in system decoupling and platform interfacing, and indicate the significantly improved accuracy and stability of the system.

Simulation study on pitch system of floating wind turbine

Due to the complex sea conditions, floating wind turbines produce unbalanced loads. Firstly, this paper will take NERL-5MW floating wind turbine as the model, and apply brainstorming algorithm (BSO) to the independent pitch system based on PID azimuth weight coefficient. Then, a joint simulation will be carried out in OpenFAST-Matlab/Simulink to study its impact on the load of floating wind turbine. Finally, the simulation results reveal that compared with the independent pitch system based on PID azimuth weight coefficient, the proposed method can reduce the load of the floating platform to a certain extent.

Modeling of Combustor-Turbine Vane Interaction Using Stress-Blended Eddy Simulation

Modeling the interaction between gas turbine engine modules is complex. The compact nature of modern engines makes it difficult to identify an optimal interface location between components, especially in the hot section. The combustor and high-pressure turbine (HPT) are usually modeled separately with a one-way boundary condition transfer to the turbine inlet. This approach is not ideal for capturing all the intricate flow details that travel between the combustor and the turbine and for tracking hot streak migration that determines turbine durability. Modeling combustor-turbine interaction requires a practical methodology that can be leveraged during the engine design process while ensuring accurate, fast, and robust CFD solutions. The objective of this paper is to assess the effectiveness of joint simulation versus co-simulation in modeling combustor and turbine interaction. Co-simulations are performed by exchanging information between the combustor and the turbine stator at the interface, wherein the combustor is solved using Stress-Blended Eddy Simulation (SBES) while the stator is solved using RANS. The joint combustor-stator simulations are solved using SBES. The benefits of using SBES versus LES are explored. The effect of the combustor-stator interaction on the flow field and hot streak migration is analyzed. The results suggest that the SBES model is more accurate than LES for heat transfer predictions because of the wall treatment and the joint simulation is computationally efficient and less prone to interpolation errors since both hot section components are modeled in a single domain.

High performance InGaAs/InP avalanche photodiode integrated with metal-insulator-metal microcavity

Reducing the dark current of InGaAs/InP avalanche photodiodes (APDs) is an important way to improve its performance. Decreasing the active size can reduce the dark current but sacrifice the quantum efficiency. In this paper, the Metal-Insulator-Metal (MIM) microcavity is integrated with an APD, which can converge light from tens of microns to several microns, to compensate for the loss of detection efficiency caused by the reduction of the size of the APD. Through photoelectric joint simulation, the optical response of the device can be obtained, and the coupling effect between the MIM structure and the APD can be analyzed directly. The simulation results show that the signal to noise ratio of the APD integrated with the MIM microcavity is twice of the MIM free traditional APD, and the 3dB bandwidth reaches 5.8 GHz. When the MIM microcavity is applied to an APD array, the optical crosstalk between pixels is found to be negligible.

Simulation Calculation of Air Conditioning System Under Complex Vehicle Conditions

Based on the Simulink the vehicle air conditioning simulation platform for the whole vehicle is established. The multi model joint simulation system can predict the performance parameters and energy consumption of the air conditioning system under the conditions of different vehicle speed, temperature and humidity. It can coordinate the simulation of the temperature change process inside the passenger compartment with the performance of the air conditioning system.