1. Introduction
As the global usage of electric vehicles (EVs) grows, the need for effective charging infrastructure has become a key concern. The proper planning and deployment of EV charging infrastructure are essential for the widespread adoption of EVs and the transition towards sustainable transportation. An effective EV charging infrastructure should be able to meet the increasing demand for charging while reducing energy consumption and environmental impacts. The optimization of EV charging infrastructure involves several factors, such as user demand, infrastructural cost, energy consumption, and environmental impact. The integration of both onboard and offboard charging optimization can help to address these factors and improve the overall efficiency of EV charging infrastructure and deployments. Furthermore, the deployment of EV charging infrastructure should consider various charging strategies, such as dynamic pricing, demand response, and battery storage, to optimize charging efficiency and reduce energy costs. The placement of EV charging stations is also critical for optimizing charging efficiency and reducing environmental impact. To reduce charging demand, traffic congestion, and emissions, optimal station placement should take into account user behavior, travel patterns, and geographical factors. Furthermore, the optimal placement of charging stations should be able to meet the growing demand for charging and reduce the waiting timestamp for charging battery packs. This paper proposes a deep Q network (DQN) using multimodal bioinspired analysis (ALO and MFO) for the optimal planning and deployment of EV charging infrastructure that integrates both onboard and offboard charging optimization, charging strategies, and optimal station placement.
The remainder of this paper is structured as follows.
Section 2 presents an overview of related work in EV charging station planning techniques.
Section 3 discusses the design of the proposed DQN with multimodal bioinspired analysis.
Section 4 presents the results and discussions of both conventional and proposed frameworks. Finally,
Section 5 presents the conclusion of the research work.
2. Review of Related Literature Work
Electric vehicles have gradually emerged as an important component of modern transportation and energy systems. Accelerating the development of EVs is posing enormous opportunities and challenges not only for infrastructural development but also in energy management and environmental sustainability. A higher demand for vehicles increases their charging infrastructure efficiency and sustainability while being compatible with power grids, renewable energy sources, and distribution networks. Optimizing the design, placement, and operation of electric vehicle charging stations seeks to make them efficient, reliable, and capable, yet with reduced environmental impacts in the process. The literature that has been reviewed cuts across a variety of approaches and techniques concerned with diverse problems in EV charging infrastructure. Among the methods developed, optimization algorithms are the most important and have been demonstrated to facilitate site selection, capacity planning, energy management, and load balancing. Many of the studies have stressed the need to take an integrated approach to cover technical aspects, like grid integration or power quality as well as economic and environmental factors. This holistic perspective is key to ensuring that EV charging stations are congruent with the broader carbon reduction agenda and wider sustainable energy systems goals.
To enhance the EV charging infrastructure and network performance, several methods have been explored. The improved gazelle optimization algorithm was employed to optimize solar and battery integration in EV station design, leading to improved efficiency but exhibiting limited scalability for larger grids [
1]. A Hybrid RERNN-SCSO technique was used for power quality control in microgrids, which enhanced EV charging stability despite its complex implementation [
2]. Incorporating an automatic variac transformer improved smart grid performance by using EVs as smart loads, enhancing voltage control, although it required a costly system setup [
3]. Neural network optimization techniques optimized logistics for battery recycling, resulting in increased efficiency, yet faced limitations in generalizing to diverse recycling needs [
4]. The Jaya grey wolf optimization method achieved a power quality improvement in EV charging stations by reducing harmonic distortion, despite a complex algorithm structure [
5]. The implementation of the IoT-based solar EV charging system offered user-friendly integration and increased efficiency, although it incurred high initial costs [
6]. Similarly, the integration of distributed energy resources and FACTS devices improved EV station performance in deregulated environments, but real-world testing was limited [
7].
The use of vehicular edge computing for charging station navigation reduced decision-making latency, although it depended on a reliable vehicular network [
8]. Online estimators optimized charging stop planning based on real-time data, enhancing the user experience, but the accuracy dropped when data quality was poor [
9]. The GJO-APCNN technique effectively balanced loads in charging stations, though its algorithm was computationally intensive [
10]. The combined algorithms were genetic algorithms and the fuzzy analytic hierarchy (FAH) process improved EV station location and capacity but was computationally demanding [
11]. Many-objective evolutionary algorithms facilitated site selection for EV charging stations, increasing service coverage while facing scaling challenges in larger urban areas [
12]. The grey wolf optimization (GWO) approach enabled solar and energy storage integration for EV charging, though its benefits were limited to sunny regions [
13]. The hybrid techniques for renewable energy integration enhanced sustainability and reduced grid strain, requiring a robust renewable energy infrastructure [
14]. A study on Uber and Lyft EV infrastructure deployment found it feasible for ride-sharing, though synchronizing charging times posed a challenge [
15]. The hybrid genetic algorithm-simulated annealing method improved distribution network resilience via optimized EV station placement, despite its high computational demands [
16].
The IoT and cloud computing integration enhances the real-time management of EV stations but raises data security concerns [
17]. Techno-economic planning is used in sector-coupled energy systems with improved energy efficiency and cost savings for EVs, albeit with high initial investment requirements [
18]. Optimal path planning reduces the travel time and energy consumption for EVs, though it has limited adaptability to real-time traffic changes [
19]. One-way car-sharing facility planning offers improved service availability, despite difficulties in predicting user demand [
20]. Multi-objective optimization enhanced network reliability and efficiency, yet its applicability was limited to urban areas [
21]. Distributed generation planning improved reliability and reduced losses in distribution networks, but with integration challenges persisting [
22]. Multi-period investment planning for electricity distribution reduced costs through demand forecasting, though future demand predictions remained uncertain [
23]. Urban planning for environmental development facilitated sustainable EV infrastructural deployment, lacking adaptability in planning models [
24]. Meta-heuristic route modeling optimized energy-efficient routing for diverse road surfaces, with limited urban applicability [
25]. Machine learning for renewable energy planning improved prediction accuracy and system efficiency, albeit with high computational requirements [
26]. Microgrid scheduling with battery swapping lowered energy costs and enhanced grid stability but incurred high maintenance costs [
27]. GIS-based site selection for EV charging improved accuracy, though data quality was inconsistent across regions [
28].
The dynamic road network model accurately forecasted charging loads, but its application was limited in small or rural areas [
29]. The patent citation network analysis identified trends in charging technologies, focusing on patent-registered innovations [
30]. Multi-agent Q-learning optimized EV infrastructure planning considering battery life and improved sustainability but faced coordination challenges [
31]. An EV charging transaction analysis dataset provided insights into charging patterns, despite regional data bias [
32]. The pseudo-inspired gravitational search algorithm enhanced distribution network resilience and reduced energy losses, though the computational intensity was high for large networks [
33]. Stochastic EV loading and natural disruption management enhanced grid reliability under uncertain conditions, with resource variability posing a challenge [
34]. Smart decision-hunting optimization improved the EV scheduling efficiency, though struggling to adapt to dynamic conditions [
35]. Valet charging service optimization reduced user wait times and improved service efficiency, although setup costs were high [
36]. The KOA-DRN approach for microgrid charging stations improved the power quality and system reliability, but integrating the approach into the existing infrastructure was complex [
37]. The hybrid techniques for energy management in EV stations and distribution systems enhanced energy efficiency but were operationally complex [
38]. The hybrid optimization for network reconfiguration improved network reliability and efficiency, with significant computational demands for large networks [
39]. Lastly, a sustainability assessment for EV charging station locations aligned site selection with green energy goals, although its application was restricted to regions with abundant renewable energy sources [
40].
The fast deployment of electric vehicles (EVs) needs the creation of effective and long-lasting charging infrastructures. For EV charging station optimization, the genetic algorithm (GA) has more limitations that reduce the efficacy in dynamic and real-time applications like slow convergence and early stalling in local optima, making it less effective at solving high-dimensional, complex issues. Additionally, its scalability is limited by the high computing cost resulting from recurrent crossover and mutation processes. The GA is not flexible enough to adjust to changes in EV demand, traffic patterns, and grid conditions in real-time, which makes it unsuitable for dynamic energy management [
41,
42,
43]. Although particle swarm optimization (PSO) is effective in solving many optimization problems, there are a few limitations for energy management and EV charging station placement. Premature convergence is a significant problem, as particles lose their diversity and become stuck in local optima, making it impossible to discover the optimal global solution. The lack of real-time adaptation limits its efficiency in managing dynamic energy prices, traffic flow variances, and grid load fluctuations [
44,
45,
46].
Ant lion optimization (ALO) prevents premature convergence, provides a strong balance between exploration and exploitation, and effectively handles geographical restrictions and power limitations. ALO is well-suited to large-scale EV charging station networks where appropriate placement is critical to ensure optimal coverage and load balancing [
47,
48,
49]. Moth flame optimization (MFO) is beneficial in dynamic and real-time optimization scenarios, improves the exploration in the early phases of optimization, and reduces the chance of becoming trapped in local optima for EV charging [
50].
The selection of ALO and MFO over other bioinspired algorithms, such as GA and PSO, is due to their numerous advantages. The proposed DQN integration with ALO and MFO successfully optimizes large-scale EV charging networks by managing complex and high-dimensional limitations, adjusting charging capabilities and station placements dynamically in response to demand, preventing premature convergence, and allowing for quick real-time optimization for station placement.
5. Conclusions
The placement of EV charging infrastructure/stations is essential for charging EV batteries to develop pollution-free transportation, thereby supporting an eco-friendly environment. This article proposes the concept of a deep Q network using multimodal bioinspired analyses like ALO and MFO for optimal planning and deployment of EV charging infrastructure to enhance performance and power quality. Several performance metrics are measured and examined for the proposed scheme, including installation cost efficiency, peak and off-peak energy utilization, average wait time, availability of charging slots, user satisfaction, environmental impact, carbon emission reduction, scalability, and operational robustness.
Further, various power quality parameters such as voltage characteristics (under sag, swell, overvoltage, undervoltage, flickers, and notches), power characteristics, frequency characteristics, and efficiency are measured and examined. To provide the optimal station location and effective energy use in real-time applications, the DQN combined with the ALO and MFO frameworks is used, which reacts dynamically to changes in EV demand, traffic congestion, and energy grid conditions. The following gives a summary and the major benefits of the proposed system based on the overall cumulative findings.
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The proposed DQN, ALO, and MFO integration improves availability and demand responsiveness by dynamically adjusting charging station distribution based on past and present traffic patterns using real-time learning.
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To ensure effective and responsive placement, the proposed DQN, ALO, and MFO integration adaptively fine-tunes charging station sites to correspond with new road networks, urban expansion, and changing grid circumstances.
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The proposed method has an average installation cost of USD 1200 per unit, which is significantly lower than competing alternatives (USD 1500, 1600, and 1700). This leads to a 20% cost efficiency increase over the least efficient method.
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The optimal energy utilization is 85% during peak hours, i.e., 10% higher than the next best method, and 92% during off-peak hours, i.e., 7% higher than the next best method.
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The proposed method increases customer satisfaction by reducing the wait time to 5 min and ensuring 95% charging slot availability, which is much higher than other methods.
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The proposed method reduces carbon emissions by 30%, demonstrating its significant environmental benefits when compared to competing methods that lower emissions by just 22%, 18%, and 15%, respectively.
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The proposed method is exceptionally robust, retaining 95% performance under stress, ensuring resilience and reliability in dynamic environments.
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The proposed system provides voltage waveforms that show stable performance, with a 2 V sag lasting 2 s and a 3 V swell lasting 1 s, exhibiting effective voltage control and operational stability.
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The proposed system stabilizes the voltage at 12.05 V, reducing flicker to only 0.05 V and improving overall system reliability and performance. The proposed method shows a better performance in managing voltage notches, keeping voltages at 12.03 V with only 0.03 V notches, indicating improved stabilization.
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The voltages of the proposed methods remain a little higher at approximately 12.03 V, which means the 0.03 V notches found show a superior performance in handling notches. This can ensure better voltage stabilization compared with the un-optimized and original methods.
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The proposed system ensures the frequency characteristics remain consistent during the simulation period and are maintained at a set point, preventing significant frequency fluctuations.
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The proposed method greatly increases system efficiency from 90% to 97.5%, hence improving overall system performance and energy consumption.
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The proposed approach supports a 50% increase in EV adoption and has an exceptional scalability score of 90.
Thus, based on the results for the proposed system, it is concluded that the proposed deep Q network with multimodal bioinspired analysis, such as ALO and MFO, outperforms existing methods. Therefore, it is recommended for optimal planning and deployment of EV charging infrastructural applications.
Limitations and Future Scope
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This work focused on simulation-based validation, and future work will explore city-wide deployment models with extensive EV fleets and distributed charging hubs to further assess scalability.
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The present study leverages the DQN integration with the ALO and MFO framework to optimize EV charging stations in real-time. The usefulness of the proposed approach has been established via actual performance comparisons, including enhanced energy utilization, charging slot availability, and cost efficiency. However, statistical significance testing may be used in subsequent research to provide additional validation in extensive real-world implementations.
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The limitations in grid infrastructure are among the possible hardware restrictions.
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To guarantee successful market integration, regulatory obstacles including dynamic pricing rules and cybersecurity threats must be taken into account.
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To enable large-scale deployment, legislators, grid operators, and EV manufacturers must work together across several stakeholders due to practical feasibility issues like cybersecurity risks, user adoption obstacles, and economic sustainability.
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The proposed scheme, despite scoring all the goals concerning setting up EV charging infrastructure, was not without limitations. The first and foremost condition essential for the model performance is proper input in the form of real-time traffic and demand patterns. In this regard, access to very high computational power to train DQNs also poses another challenge for small-scale deployment. Therefore, future work can focus on integrating carbon emissions by using renewable energy sources, whereas lightweight deep-learning-models will enable real-time deployment in resource-constrained environments. Furthermore, the extension of the model to a multi-agent system would allow the collaborative optimization of several charging stations for better overall grid stability.