The VDE-AR-N 4110 is the guideline for the connection and commissioning of photovoltaic systems and other renewable energy systems with medium voltage. Its update from September 2023 includes a simplified individual verification procedure for generation systems with an output of 135 kW to 950 kW and covers a wide range of topics, from technical requirements to the certification of systems. It is applicable to all new systems as well as modifications or extensions to existing systems binding. The Association for Electrical, Electronic & Information Technologies (VDE) has developed VDE-AR-N 4110 to ensure that medium-voltage systems are safely and reliably connected to the internal and public power grid.
What are technical connection rules?
Technical connection regulations are standards and guidelines that safe connection of electrical installations to the public power grid define. They regulate the efficient and risk-free transmission of electrical energy and the proper functioning of the systems. The standard, also known as TAR medium voltage defines requirements for renewable energy systems, storage systems and mixed systems in the medium-voltage grid. It specifies the requirements and procedures to be observed when planning, installing and commissioning such systems. The TAR Medium Voltage of the VDE Network Technology/Network Operation Forum complies with the European Network Codes and improves grid stability through extended requirements for short-term voltage dips and reactive power provision.
The VDE-AR-N 4110 in medium voltage
Compared to other standards such as VDE 4105, VDE 4110 focuses on the integration of larger systems, such as commercial PV systems, wind farms or combined heat and power plants (CHP), into the medium-voltage grid. This places special demands on the safety and performance of the systems. Both standards play an essential role in the energy supply system and specify specific requirements to ensure the safe integration of systems. VDE 4110 deals specifically with a variety of topics, including Network perturbations, Mains protection, Maintenance, Synchronization with the network, Power supply quality and Safety requirements. It also defines procedures for the certification and grid connection of systems as well as requirements for grid planning and emergency power supply.
Compliance with the directive is essential to ensure the safety and reliability of medium-voltage systems. Applying these rules minimizes the risk of power failures, short circuits and other dangerous situations that can lead to serious damage to equipment and people. In addition, compliance with VDE-AR-N 4110 prescribed by law and is monitored by the relevant authorities. Companies that do not comply with the technical connection rules must expect legal consequences such as Fines or even the Withdrawal of the operating license calculate.
Brief overview of the requirements of VDE-AR-N 4110
VDE-AR-N 4110 specifies a number of requirements that must be observed during installation. These include, among other things, the selection of the correct Cables and Cablesthe correct Dimensioning from Protective devicesthe avoidance of electromagnetic interference and the proper Earthing of the systems. All areas of the directive have far-reaching effects on the planning, construction and operation of medium-voltage projects. In particular, system operators must now ensure that their systems meet the Stable mains frequency which represents an additional challenge.
It stipulates that systems must be able to stabilize the grid in the event of frequency changes and provide reactive power. To this end, it regulates the requirements for the grid connection point and the connection technology in order to meet the grid operator's safety and operational requirements. Compliance with these requirements improves grid stability and security, facilitates the connection of generation plants, promotes renewable energies and improves the Interoperability between different systems and the electricity grid. Standardization and clear specifications ensure efficient integration and a reliable energy supply.
In order to optimize project processes and avoid delays, the systems should be qualified specialists be planned and installed by specialists with the necessary expertise and certifications. In addition, the materials and components used during installation must meet the requirements of VDE-AR-N 4110 and be certified.
What are the target groups of VDE-AR-N 4110?
Many stakeholders are affected by VDE-AR-N 4110. The main target groups are grid operators, system planners, operators and installers and, of course, all component manufacturers. System operators must ensure that their systems meet the technical requirements and safety standards of the standard in order to be able to connect them successfully to the medium-voltage grid. Energy supply company are also affected, as they have to guarantee the stability and security of the network. Planners and installers are obliged to comply with the requirements of the standard when planning and installing systems. Public facilities such as municipal utilities and regulatory authorities must monitor compliance with the standard and create references and standards, some of which do not yet exist. Consumers benefit indirectly of the standard, as a stable and safe power supply, guaranteed by VDE-AR-N 4110, is of crucial importance to them, whether in the household or in a business environment.
Frequent challenges in the implementation of VDE-AR-N 4110
The implementation of the directive can be associated with a number of challenges. One of the most common challenges is its complexity, which can be quite high. This is especially true for solar installers and professionals who are not familiar with medium-voltage systems. Careful planning and training are required to ensure that the requirements are interpreted and implemented correctly. In addition, technical difficulties such as limited space for the installation of components or difficulties in procuring high-quality materials can arise.
Steps to fulfill the standard
Companies that implement projects that are affected by VDE-AR-N 4110 should always follow the following steps:
A thorough and Careful planning is the key to compliance with the directive. The requirements should be understood and analyzed at the design stage of a renewable energy project to ensure that the systems are properly planned and dimensioned.
Regular Training courses and Certification of all employees to VDE-AR-N 4110 ensure that they have the necessary specialist knowledge and skills to meet the requirements.
Permanent Quality controls in the form of regular inspections and maintenance guarantee that the systems comply with current standards and function properly.
A thorough and complete Documentation of all work, modifications and inspections carried out is essential in order to prove compliance with the standard and to present it if required.
Advantages of complying with the VDE-AR-N 4110 guidelines
Compliance with VDE-AR-N 4110 offers a number of advantages. Firstly, it contributes to the safety of employees and the public by minimizing the risk of accidents and damage. Secondly, it ensures the reliability of medium-voltage installations by ensuring that they function properly and comply with requirements. Finally, it enables companies to avoid legal consequences such as fines and the withdrawal of operating licenses.
Conclusion
VDE-AR-N 4110 is a comprehensive guideline for the technical connection rules in the medium-voltage sector and a building block of all DIN EN, VDE and IEC specifications for commercial PV systems. Compliance with these rules is crucial to ensure the safety and reliability of medium-voltage systems. Through careful planning, training and quality control, companies can ensure that they meet the requirements of the standard. Compliance with these guidelines offers a wide range of benefits and enables companies to avoid legal consequences. For more information on VDE-AR-N 4110, there are a variety of resources available that can be used to improve understanding and implementation of these important connection rules.