Akdulum, Aslan; Sİyambaş, Yusuf; Çakiroğlu, Ramazan; Uzun, Gültekİn

This study investigates the relationship between cutting forces and real-time energy consumption signals during the turning of titanium alloys, as well as the impact of various cooling methods on these forces. A hybrid approach combining energy signal analysis and forward regression modeling was applied to model the cutting forces. This work aims to model and predict cutting forces using individual and multiple signal data fusion approaches using data obtained from energy signals, such as reactive power, power factor, apparent power, and active power. A random forest regressor was preferred for model set-up, and the Scopt Optimizer was preferred for fine-tuning the hyperparameters. Six methods were used to score the features based on their importance level. The results showed that multi-energy signal data fusion outperforms the models based on single signals in predicting cutting forces. This method offers a new approach for optimizing metrics, such as the main cutting force (Fc) and feed force (Ff). The MAPE value of 4.91% obtained in the modeling estimation of the Ff emphasizes the power of the proposed method. The presented framework has the potential to increase processing performance while reducing energy consumption. The findings highlight the effectiveness of combining energy signals and machine learning in developing sustainable manufacturing processes. The proposed model can be adapted to different processing scenarios and provide a basis for industrial applications.

CAN, EROL

In renewable energy-sourced power systems, asynchronous motors serve as elements that both produce and consume electricity. The stability and efficiency of the asynchronous motor in renewable energy system should be considered. Although performance optimization studies have been carried out using power circuits that control the asynchronous motor fed with solar energy and control units such as proportional, integral, derivation (PID), and Fuzzy logic; They may be insufficient to eliminate and reduce vibrations in the output values of an induction motor fed with a renewable energy source. Losses occur as the system performance decreases constantly due to oscillations. In this study, an induction motor power system is optimized with the extra control coefficient (ECCA)-PID, which provides semi-linear control for the first time, unlike the power systems controlled by other linear controllers used so far to reduce oscillations, and the vibration losses are eliminated. The speed oscillations, torque oscillations, and oscillation losses of the induction motor in the system are controlled by conventional PID, and Fuzzy logic controllers in order to demonstrate the effectiveness of the proposed method in simulation and experimentation. Then, the results are compared after the proposed method are examined. As a result of the comparisons, while the motor oscillations and losses in the power system continue throughout the control period in traditional control methods, the proposed method reduces the losses to zero in a large part of the control period.

Can, Erol

The need for functional photovoltaic systems with multiple inputs used in energy storage devices is increasing day by day. In addition to having sufficient performance, these units are a good alternative to integrated converters with their low costs. In terms of these advantages, a multi-port DC–DC converter is recommended for solar energy systems in this study. In this multi-pot system, each port has a specific purpose. Two of them are renewable sources, one is the battery set and the other is the load port. Although this topology is developed for standalone systems, it can be easily adapted to other different applications. The system can provide energy from each input source independently or by combining them, and any renewable source can be charged to extend the life of the battery set, whether discharged or charged. While the system can provide energy in some periods of time without the need for input sources or by combining all elements in the system, a different renewable source can also be used to extend the life of the discharged or charged battery set. A few extra features make the system superior to other existing systems; First of all, the PV source and battery are directed to the same point. Sometimes, only the solar cell charges the battery, providing safe grounding for both, and secondly, the output is isolated from other connection points. These advantages are given by comparing them with existing systems. The advantage that is different from other topologies is that the proposed method can continue battery charging in 3 ways with the switches reserved for PVs. The first is discontinuous mode, the second is semi-continuous mode and the third is continuous mode. This mode of operation is preferred according to the amount of energy received from the sun. In this way, it offers a functional charging capability. After the proposed system design and numerical studies, it is also applied experimentally.

Demİrİz, Ahmet Oğuz; Bayrak, Osman Ünsal; Bayata, Halİm Ferİt

Today, the existing traffic networks cannot cope-up with the increasing transportation demands and traffic volume and fail to meet the demands. This causes economic and social losses. Increasing transportation demands and traffic volume in Erzincan city center of Turkey cause the main arteries and junctions to be insufficient. In such problems, solutions are generally produced using parameters such as trip and delay durations and exhaust emissions. Another point to be considered is to ensure the improved intersections to work as a whole. In this study, the main arteries and the junctions on these in Erzincan city center were discussed. In this context, totally 14 intersections were tried to be improved. Suggestions were offered regarding delay time, travel time, queue lengths, NOx and CO2 emissions, and average speed values as the design criteria. Simulations were made in AIMSUN program for the current situation and four different scenarios. Analytical Hierarchy Process (AHP), which is one of the multi-criteria decision-making methods for the network was employed to determine which scenario was more appropriate. At the end of the study, decrease of up to 23% for travel time, 47% for delays, 48% for queue lengths, 11% for NOx, and 13% for CO2 and increase of up to 30% in average speed were obtained. According to AHP, Scenario 4 had the highest priority value among all alternatives. Moreover, the reliability of the results was ensured by supporting the mesoscopic simulation with AHP which is a multi-criteria decision-making method.

Sahin, Yakup; Ting, Naim Suleyman

This paper introduces a novel active snubber cell for soft switching PWM DC–DC converters. In the proposed converter, the main switch is turned on under zero voltage transition (ZVT) and turned off under zero voltage switching (ZVS). The auxiliary switch and all of the other semiconductors in the converter are turned on and off with soft switching (SS). There is no extra voltage stress on the semiconductor devices. Besides, the proposed converter has simple structure and ease of control due to common ground. In this treatise, the theoretical and mathematical analysis of the proposed converter are presented and the design procedure of converters is also provided. The simulation study at 100 kHz switching frequency and 600 W output power are conducted. The experimental prototype of converter is operated under same conditions. Both the simulation and the experimental prototype exhibits similar performances. Ultimately, the efficiency of the proposed converter is 95.7% at nominal power.

Sahin, Yakup; Ting, Naim Suleyman

In this paper, a new snubber cell for soft switched high set-up DC–DC converters is introduced. The main switch is turned on by zero-voltage transition and turned off by zero-voltage switching (ZVS). The main diode is turned on by ZVS and turned off by zero-current switching. Besides, all auxiliary semiconductor devices are soft switched. Any semiconductor device does not expose the additional current or voltage stress. The new snubber transfers some of the circulation energy to the output side when it ensures soft switching for main semiconductor devices. Thus, the current stress of auxiliary switch is significantly reduced. Besides, the total efficiency of converter is high due to the direct power transfer feature of new converter. A theoretical and mathematical analysis of the new converter is presented, and also verified with experimental set-up at 500 W and 100 kHz. Finally, the overall efficiency of new converter is 97.4% at nominal output power.