Control and Display for EV Charging Stations

Introduction

In 2018, we were contacted by the largest electricity distribution company in Italy. The goal for the following years was to create a nationwide network of EV charging stations for public use.

CJB was responsible for designing an industrial integration solution, including electronics and displays, to be integrated into the design and mechanics provided by the client.

To date, CJB has supplied the client with approximately 20,000 units of these EV charging stations, which have been deployed across the national territory.

How an EV Charging Station is Made

EV charging stations for fast charging are typically composed of a robust containment structure, housing technologies for power control, communication with central energy distribution systems, and data visualization for end users. As these stations are distributed throughout the national territory and located roadside, all electronics must ensure high operational standards even in extreme environmental conditions (heat, cold, humidity, rain, hail, wind, snow).

Power Component

The power electronics usually operate at 240, 400, or 800 volts and are responsible for supplying or interrupting the energy delivery to the connected EV.

Communication Component

The communication electronics interact with central systems to authenticate the user and transmit the authorization to the power component to deliver energy to the connected vehicle in varying measures. This component also continuously communicates and monitors the operational status of the charging station, transmitting all operational data and statistics to the central systems.

Data Visualization Component

To enable the end user to interact with the charging station, it is necessary for the station to have a display that is readable and operational under challenging environmental and atmospheric conditions. For safety and redundancy reasons, the display control electronics are separate from the power control electronics. CJB has designed and provided all the electronics dedicated to controlling the display.

The Role of CJB in Designing the Charging Stations

CJB designed and provided all the electronics dedicated to controlling the display for visualizing information for the end user.

Designing and integrating the display involved the following development phases:

Requirements Analysis, Costs, and Delivery Times

The client requested a solution study with target prices, implementation timelines, and a guarantee of a consistent supply for at least 10 years at a regulated price.

The client also provided targets for failure rates and requested the development of a support plan for repairing any faults.

Among the design specifications, the client specified that CJB would need to develop a custom communication protocol to ensure the display electronics could communicate with the power management electronics, which would be provided directly by the client.

Integration into Existing Design

The client provided mechanical drawings and prototypes of the housing mechanics and asked CJB to study a solution for housing the display and its associated electronics.

Project Design and Specifications

Starting from the 3D mechanical models provided by the client, CJB designed a housing frame and selected a display and electronics based on ARM Linux technology that met the required technical specifications.

These included:

• Ultra-bright Display: 1000 nits extended-range (capable of operating at ambient temperatures up to 70°C, even in direct sunlight).

• Protective Glass: 6mm anti-burglary and anti-vandal glass with IK10 certification, able to withstand at least 20 joules of impact force (e.g., hail or vandalism with thrown stones).

• Bonding and Adhesion: The protective glass was bonded with optical clear resin (OCR), ultra-clear and resistant to ultraviolet solar radiation and adverse weather conditions.

Simulation and Project Development

CJB accelerated the prototyping and implementation of the project using SoftPLC technologies that utilize Inter-Process Communication mechanisms. This approach allowed for the rapid modeling of a complex state machine and quick interfacing with the power electronics.

A 10.1" display was chosen, with a guaranteed minimum brightness of 1000 nits and a lifespan exceeding 10 years.

An industrial ARM board with a Quad-Core processor and graphics accelerator was custom-designed for the display control electronics, ensuring smooth operation of the User Interface.

Durability Testing and Certifications

The prototypes underwent destructive tests such as vibrations, shocks, torsions, and pressures according to the standards required by IK10 certification. Operation at extremely high and low temperatures was certified using a temperature-controlled climatic chamber available at CJB. Our electronics successfully passed all EMI/EMC tests.

Series Assemblies

CJB began assembling the first batches in its equipped laboratory for series production.

Future Developments

Current charging stations do not feature a touch panel, but prototypes have been developed using Displax touch display technology, capable of functioning even in rain, snow, humidity, and direct sunlight, while still meeting the ruggedness standards dictated by IK10 certification.

Results Achieved

CJB has delivered nearly 20,000 complete systems for roadside deployment.

Skills Acquired

With this project, CJB entered the world of public HMI (Human-Machine Interaction) installations positioned roadside.

The know-how gained has been made available to CJB's clients operating in the outdoor vending machine sector, which must function in challenging atmospheric conditions.

To date, CJB has the capability to design or convert HMI systems, including EV charging stations for electricity distribution, making them rugged, vandal-resistant, interactive, cloud-connected, and updated to the latest technological standards.

If you need to develop or integrate charging stations or infrastructures for EV charging, please contact us for more information.