Energy Management System for Electric Vehicle DCFC Stations

Abstract

As electric vehicle (EV) adoption accelerates, the development of Direct Current Fast Charging (DCFC) infrastructure becomes essential to support the growing demand. British Columbia aims to achieve 100% zero-emission vehicle adoption by 2035, with plans to expand its current 4,700 public charging stations to 10,000 by 2030, reinforcing its commitment to a sustainable, net-zero transportation future.

Energy Management Systems (EMS) play a critical role in enhancing the efficiency and capacity of BC Hydro’s charging network. By optimizing power distribution among chargers, EMS can mitigate transformer overloads, prevent site shutdowns, and reduce the need for costly infrastructure upgrades. This capstone project explores the implementation of EMS at DCFC stations, focusing on regulatory challenges and benchmarking load management systems.

In Canada, the regulatory framework for EMS faces significant challenges due to the absence of specific performance requirements and a standardized certification process within the Canadian Electrical Code (CEC). This gap places considerable responsibility on product owners and technical safety authorities. While CSA SPE-343:21 offers guidance on EMS design and testing, the absence of a dedicated standard hinders certification and adoption.

Additionally, the DCFC EMS market is advancing more slowly than Level 2 chargers, leaving utilities like BC Hydro with limited options. This is likely due to load sharing being more critical in long-stay charging environments rather than short-stay (DCFC) settings. Initial testing of dynamic load-sharing features using BC Hydro’s current network management platform, EvGateway, showed promising results, particularly in facilitating priority-based charging. However, further testing is required to thoroughly evaluate EvGateway’s capabilities.

Introduction

Transportation accounts for 39% of greenhouse gas emissions in British Columbia, making the decarbonization of this sector a top priority. A crucial element of this effort is expanding electric vehicle (EV) charging infrastructure to support the transition to zero-emission vehicles (ZEVs). BC Hydro, the province’s primary electricity provider, plays a key role by delivering clean, renewable energy and advancing sustainable solutions. Powertech Labs, BC Hydro’s subsidiary, supports innovation in energy management systems and EV infrastructure.

BC Hydro plans to expand its fast-charging network from over 150 chargers at the end of 2023 to 3,000 ports by 2030, in alignment with the Government of B.C.’s EV network plan. However, challenges such as inefficiencies and transformer overloads due to static power allocation remain. To address this, innovative energy management solutions are needed to optimize power distribution and ensure reliable service.

Methodology

Certification Standard
A comprehensive literature review was conducted on certification standards and performance requirements for load management, focusing on Section 8 of the Canadian Electrical Code, Articles 625 and 750 of the National Electrical Code, municipal guidelines, and materials from Technical Safety BC. Practical insights were gained through consultation with a City of Surrey Electrical Supervisor, offering context on real-world implementation of load management strategies and certification.

Benchmarking DCFC EMS Solutions
The project team attended the Everything Electric Canada event in September to explore DCFC EMS solutions from major vendors. Additionally, one student, employed at an electrical consultancy firm, gained direct insights from vendor seminars. We benchmarked EMS solutions, focusing on industry standards, user experience, ease of maintenance, and identified areas for improvement.

EvGateway Testing
The EvGateway testing plan was developed using vendor documents like the Load Management User Module and Load Profile Setup Assessment Form. We collaborated with BC Hydro and Powertech Labs to refine the plan. Testing involved evaluating dynamic load sharing and first-come, first-serve profiles using ABB chargers and various EVs. Fail-safe mechanisms were tested by simulating network outages.

ABB Terra Gateway Pro Testing
The testing plan for the ABB Terra Gateway Pro was developed using vendor documentation and insights from BC Hydro and Powertech Labs. The plan included performance standards and fail-safe scenario testing to ensure technical alignment with operational needs.

Figure 1: DCFC charging station

Figure 2: Testing set-up in PowerTech

Results and Discussion

Certification Standards
The Canadian Electrical Code (CEC) provides a foundational framework for EMS but lacks specific performance requirements and a standardized certification process, creating challenges in implementation and regulation. Local authorities and utility providers are tasked with addressing these gaps to ensure EMS systems operate safely and efficiently. Technical safety authorities have introduced variance processes that facilitate the implementation of EMS in Canada, primarily defining performance requirements for Level 2 chargers. These standards are based on typical driving and charging scenarios for overnight use. However, the design and performance standards for other applications, such as DCFC, remain undefined, leaving their implementation to the discretion of individual installers.

Benchmarking DCFC EMS Solutions
The development of the DCFC EMS market is slower compared to that of Level 2 chargers. Given that EMS is typically more applicable to long-stay charging scenarios, such as residential charging, the DCFC EMS market primarily targets utilities (e.g., BC Hydro), government fleets, and large-scale corporate fleets. For BC Hydro, the availability of DCFC EMS solutions remains limited, pending advancements in emerging technologies.

A review of current market offerings reveals that most software solutions share similar functionality and performance, featuring compatibility with the Open Charge Point Protocol (OCPP) and dynamic load-sharing capabilities. These attributes align with BC Hydro’s objectives of managing EV charging demand effectively and implementing load curtailment during peak demand periods.

Testing of EvGateway and ABB Terra Gateway Pro Systems
Two EMS solutions—EvGateway and ABB Terra Gateway Pro—were identified by BC Hydro for load management testing. Initial testing was conducted exclusively on EvGateway, which demonstrated adequate performance in dynamic load-sharing and first-come, first-serve management profiles. However, minor discrepancies in power limits were observed, emphasizing the need for further configuration adjustments. Additional testing of the EvGateway system is planned to fully validate its capabilities. Testing for the ABB Terra Gateway Pro solution is also scheduled to begin shortly.

Category	Evaluation Criteria
Technical Capabilities	System compatibility with DCFC infrastructure, especially with Flo, ChargePoint, and ABB chargers. Scalability and flexibility for network expansion. Performance under varying load conditions while ensuring compliance with the limits established by the EVEMS.
Reliability and Fail-Safe Mechanisms	Typical points of failure and their impact on system functionality, including downtime or safety risks. Mechanisms for safe operation during communication failures or power outages. Ability to restore safe and balanced operation after power restoration. Redundancy and fallback systems to ensure continuous functionality.
Ease of Installation and Maintenance	Simplicity in setup and configuration. Availability of clear documentation, training, and ongoing support. Maintenance and troubleshooting requirements.
Cost and Fees	Initial setup costs. Service fees for software, maintenance, and upgrades. Overall lifecycle cost relative to performance and features.
Certifications and Compliance	Ease of EVEMS certification and compliance with local regulations and technical safety requirements.

Table 2: Evaluation Criteria for DCFC EMS

Conclusion

Certification Standard
The Canadian Electrical Code (CEC) outlines general guidelines for EVEMS but lacks specific performance standards, leading to reliance on variances by local authorities. Clear certification standards, particularly for DCFC, are necessary to enhance regulatory consistency and support EV infrastructure expansion.

DCFC EMS Benchmarking
Global vendors such as ABB, EATON, and Siemens provide EMS options for DCFC chargers, with most solutions leveraging the OCPP protocol for seamless compatibility across brands. While cloud-based EMS solutions offer significant cost savings and scalability, they may pose challenges related to data security and latency. In contrast, hardware-based options, though reliable, could lead to increased logistics costs for managing BC Hydro’s extensive DCFC network. Cloud-based systems, particularly those using mobile data in remote areas, can further reduce infrastructure costs and provide enhanced flexibility.

EvGateway Testing
Successful tests of the Dynamic Load Sharing and First Come First Serve profiles showed they meet expectations. Further testing, including Fleet TOU and network outage simulations, is required to ensure complete functionality and reliability for BC Hydro’s DCFC network.

Contact Details

Rashmi Rajendran & Wilfred Lo
Email: rashmira@student.ubc.ca; wlo23@student.ubc.ca
LinkedIn: https://www.linkedin.com/in/rashmirajendran/; https://www.linkedin.com/in/wilfred-lo-5641052bb/

Dynamic Load Sharing with meter disabled: Distributes power equally among connected vehicles, but unused power from a near-fully charged vehicle cannot be reallocated, causing inefficiencies.
Dynamic Load Sharing with meter enabled: Allocates power based on vehicle prioritization and SoC, adjusting supply as charging slows to optimize power distribution and prioritize vehicles with lower SoC, improving efficiency.
First Come First Serve: Charges vehicles sequentially, fully charging one vehicle before moving to the next, a method typically used for fleet charging or long-term parking.
Fleet With TOU (Time of Use): Optimizes charging during off-peak hours to reduce costs and grid strain, making it ideal for long-term parking scenarios like residential or fleet charging.