Recharged: Charging technology for e-mobility
The company's parking lot becomes the showroom here: CuroCon GmbH demonstrates how simple and versatile electric vehicles can be charged with the right technology.
Reliable charging with high performanceHow can electric vehicles be charged quickly and reliably in a variety of scenarios? CuroCon GmbH poses this question not only for its customers in the automotive industry. The company recently built 10 charging stations on the its own parking lot, where different charging technologies and performance levels are employed.
As in a test laboratory, charging technologies for different performance levels can be tested flexibly and safely
The idea to equip the company parking lot in Zwingenberg with charging stations resulted from several customer projects, explains Michael Wißbach, managing director and founder of CuroCon GmbH. "One of our business segments is the automation of electric commercial vehicles, and this includes solutions for the charge controller in battery electric trucks. This raised the question for us: How can we safely and reliably charge electric vehicles – even with high power levels such as those needed for commercial vehicles."
When they first looked at it, Wißbach and his team quickly realized that charging technology is still somewhat in its infancy. He explains, "From standards to charge management, many things are still in flux – that's why we wanted to develop a charging infrastructure that is versatile and easy to modify." The company wanted to test and optimize this concept in its own charging park. Wißbach continues, "This is why we naturally also needed a suitable solution for the electrical systems and automation with which we cover many fields of application, AC charging with 11 kW and 22 kW, but also DC fast charging stations with 50 kW and more."
Engineering and automation for industryFrom the engineering office to the service provider for system solutions in the measurement, open-loop control and drive technology. When Michael Wißbach and Bernhard Müller founded CuroCon GmbH in 2001, they had no idea that almost 20 years later that charging systems for e-mobility would be one of the company's business segments. Or did they?
Electric drives and control technology form the technological foundation for new business segments
"The step from the test bench to charging technology is not as far as one might think at first glance," says Michael Wißbach. "We develop test systems for automatic transmissions, among other things. We simulate driving behavior with electric drives in order to test the transmission in various situations – in other words, we simulate, as it were, a 'real' vehicle with electric systems for the transmission."
The idea was to use this know-how for electric drives in real vehicles. "And that's why we started developing automation solutions for commercial vehicles and brought in our control engineering expertise. In this case, projects for which we have integrated charging operations into test systems for electric vehicles were added. We have looked into charging technology and realized that there is still a great need for flexible and versatile solutions in this area. Standards are lacking in many areas, so we believe that charging systems must develop in line with the requirements – and that is exactly our specialty."
Instead of creating a proprietary solution, we always work holistically. Therefore, we can easily integrate new functions at any time.Michael Wißbach, Managing Director CuroCon GmbH
One controller for flexible charging optionsAutomation, switching and protection technology for the charging infrastructure come almost completely from Siemens. CuroCon can use them to monitor and control all charging operations from a central controller. New functions can also be easily revised.
Ten charging stations are controlled from a central controller using a modular solution
At present, the charging infrastructure for CuroCon consists of a total of 10 charging stations: Six charging stations for employees with 11 kW charging capacity, two charging stations for visitors with 22 kW AC and two charging stations for high-power charging with direct current (DC). "We have constructed the complete system like a test field so that we can revise functions or stations at any time. It was important to us to have the ability to implement a finely modular design. We therefore rely on the same technology platform that we also use in our test systems," explains Wißbach.
"For all applications that place high demands in terms of performance or reliability, we use Siemens components almost exclusively. Functions are programmed in the SIMATIC controller and the corresponding modules are implemented in a distributed configuration in the SIMATIC ET 200SP. That way we can easily adapt both the program and the configuration to the application and change them at any time without much effort." CuroCon also uses Siemens components for the protection and switching technology. SIRIUS and SENTRON devices ensure permanently reliable switching, protection and monitoring, even under heavy loads, thus contributing to the protection of persons and vehicles – even under harsh conditions and severe environmental influences.
The solution for CuroCon GmbH
A SIMATIC ET 200SP controller with a CPU 1512SP and ECC charge controller modules for AC charging processes is installed in the central control cabinet for the charging stations, while a distributed SIMATIC ET 200SP with the corresponding ECC charge controller modules for DC charging processes is installed locally in the DC charging stations. SIMATIC AI energy meters monitor the energy consumption for the respective stations. Thanks to the modular master-slave system of SIMATIC ECC, not only can a charging solution be easily expanded with new charging stations, the central controller also simplifies the installation of firmware updates.
Dynamic load management is another central component of the charge controller application. This allows CuroCon to easily start up or shut down individual charging stations as needed or to adjust the current charging capacity at the individual charging stations as needed. If, for example, there are high number of vehicles are at the charging stations, the total capacity can be limited accordingly. When a vehicle has finished charging at the high-power charging station, the power level can be increased again at the remaining charging stations. CuroCon programmed the corresponding routines in the controller and can therefore adapt and modify them at any time.
Last but not least, the minimum amount of hardware in the distributed charging stations enables a higher degree of freedom in the individual design of the charging stations compared to conventional solutions. This allows charging stations to be adapted to save space and visually integrated in the best possible way in a wide variety of environments.
SENTRON protection, switching, measuring and monitoring devices are another part of the solution. This allows the CuroCon to easily switch the individual charging stations on or off. Thanks to the development and production of the circuit breaker in Germany as well as their 100% testing, we provide the highest quality. Our circuit breakers have been tested with significantly increased temperature range requirements and can always reliably ensure personal safety. More than that, SENTRON PAC energy meters can already enable calculation of charging energy consumption with MID-certified devices in accordance with the European Measuring Instruments Directive.
The entire solution can be configured in TIA Portal. The application examples provided free of charge by Siemens for smart charging and control of multiple charging stations serve as a starting point for customized design of charging park solutions. As a result, CuroCon benefits from its expertise on hand and can quickly implement new functions, according to Michael Wißbach. "We already have a great deal of experience with TIA Portal from our automation projects and were able to easily transfer this knowledge to charging technology. All the functions are implemented in the controller, which also operates efficiently thanks to the charge controller function blocks. This way, we have everything under control. We define which performance we measure and how, when certain contactors switch, and we monitor the entire communication with the vehicle. We can also easily implement special functions in this way, for example, defined charging periods. No problem at all."
When it comes to safe and reliable charging with high performance, Siemens is our supplier of choice.Michael Wißbach, Managing Director CuroCon GmbH
The versatile and expandable solution is also ready for innovative and complex applications
How easily even complex applications can be integrated into the existing system is currently being demonstrated by CuroCon in a project at the Technical University Darmstadt: The photovoltaic power system in the building is coupled with a battery storage system and the charging stations. "Subsequently, we want to use AI algorithms to implement an optimal charging strategy, based on the momentary power requirement and the available power of the photovoltaics and our supplier. Since we can freely program the entire application in the central controller, complex energy management can be easily integrated. I am very excited about this project," says Wißbach.
Future users will also benefit from this versatility. "With our solution, we want to offer a flexible and sustainable alternative to wall boxes, especially for applications such as parking garages or bus depots. Particularly when it comes to a large number of charging stations, our solution with a central controller also offers advantages in terms of costs." The solution can also be easily installed and expanded by local partners. "With SIMATIC technology, we are relying on a system that can be set up, commissioned and maintained by a suitably trained installer. And we also have the option of easily integrating the charging infrastructure into a higher-level control room. Because the charging technology for e-mobility is constantly developing. This is exciting – and shows the strengths of the Siemens technology. It is easy to retrofit, which enables us to adapt dynamically to the market."