In the drive solutions segment, Diehl Controls produces custom, sensorless inverters for drive systems with synchronous and asynchronous motors in the power range of 50 W to 7.5 kW. Customers can choose from platforms for connection to single-phase or three-phase household mains networks, or a 36-V battery version. Depending on the model, annual production ranges from a few hundred to one million inverters. Our top priority is the optimal design and cost optimization of the system.
Our portfolio covers three categories of frequency inverters, depending on the type of mains connection and the output power.
We adapt the platforms to customer specifications with regard to communication interface, cooling system, motor regulation, and individual features. This means we supply tailor-made systems based on proven platforms.
Currently, we offer two power categories for 230-V AC mains (3.5 kW and 5.5 kW) and one platform for 400-V three-phase supply (7.5 kW).
|Inverter||Power grid||Power||EMC-PFC||Functional safety|
|Platform 1a||230 V||50 - 1,000 W||EN 61000-3-2||EN 60335, SW Class B|
|Platform 1b||230 V / 16Amax||1 - 3.5 kW||EN 62000-3-2||EN 60335, SW Class B|
|Platform 2||400 V / 16 Amax||3.5 - 7.5 kW||EN 62000-3-2 with external chokes||EN 60335, SW Class B|
|Platform 3||230 V / 25 Amax||3.5 - 5.5 kW||EN 61000-3-12||EN 60335, SW Class B|
We have also developed prototypes for battery-powered appliances with a power of e.g. 36 V and 2 kW. Diehl Controls has already entered the professional power tools market with software solutions that enable sensorless operation of brushless motors from standstill.
The sensorless control system from Diehl Controls can drive synchronous motors from standstill to frequencies of 1.3 kHz (80,000 rpm) and also deep in the field-weakening area. At the same time, the grid power uptake conforms with the Limits for Harmonic Current Emissions for household grids (EN 61000-3-2).
This means all these platforms are perfect for compressors, fans, and pumps, e.g. for heat pumps and other HVAC applications. Sensorless control has also proven effective in battery-powered power tools.
Many applications contain several speed-controlled drives. With our multi-inverter concept, we control all these drives from a single board. This is how we simplify communication between the drives, save space, and reduce system costs for our customers.
For instance, the multi-inverter simultaneously controls the fan, compressor, and pump of a heat pump. Therefore, the main control system requires just one channel for communication and power supply. If three conventional inverters are used, the main control system would have to issue a command three times via three different interfaces.
- Active Front End
Current and future standards demand a sinusoidal current uptake from the grid. The traditional way to achieve this is with large, heavy harmonic chokes. Instead, we use an active front end. The current uptake is controlled with fast semiconductor switches and modulated in a sinusoidal form. This makes the board lighter, smaller, and cheaper.
- Extra Features
Additional safety functions can be integrated in the control systems which no longer have to be provided via the hardware components. Inverters from Diehl Controls comply with the Class B software standard. This means the software takes care of safety functions according to VDE which would otherwise require additional safety components.
This means that safety functions such as overheating protection, blocking recognition, or overpressure checks can be reliably implemented. The option of combining these additional features on the circuit board reduces costs and simplifies the system.
- Single Board
With our single-board concept, we aim to fit all electronic components on one board. We are committed to implementing this design principle irrespective of how many different components the customer requires.
This means our customers get a solution tailored to their requirements and are not forced into compromises in the form of standard solutions. Originally, this concept was developed to save costs in the white goods industry. Meanwhile, it is also successful in all other areas.
- Design for Harsh Environment
Diehl Controls has the expertise to install circuit boards not only in control cabinets, but also in harsh environments such as fan ducts - without any need for an additional housing.
We design our electronic systems so that they are more resistant to environmental influences and moisture. We achieve this for instance by providing larger spaces between the components or using optimized circuits.
Furthermore, we apply standard technologies to make the circuit boards more resistant: varnishing and encapsulation of the electronics are in-house processes at Diehl Controls.
- Smart Control
The term smart control covers a range of additional software features. For example, motors can be controlled right from the start entirely without sensors. Connection via intelligent bus systems enables an effective dialog with the main control system. This makes it possible to realize extra monitoring and comfort functions such as imbalance and foam detection or pressure and flow measurements.
Class B software can cover specific safety functions: It is possible for instance to monitor the motor and switch it off when it overheats without the need for an over-temperature switch.
Further add-on features are an early failure detection of motor wear, extra monitoring and comfort functions, and real-time performance monitoring for all motor types.
- Conformity with Standards
Our platforms are approved according to the EN 60335-1 standard with functional safety software Class B.
The inverters as individual components comply with the following EMC standards:
EMC measurements Standard Conducted RF currents EN 61000-4-6 Burst EN 61000-4-4 Surge EN 61000-4-5 Voltage short interruptions, voltage dips EN 61000-4-11 Harmonic currents emission EN 61000-3-2 (I ≤ 16 A)
EN 61000-3-12 (I > 16 A)
Voltage fluctuations and flicker EN 61000-3-3 (I ≤ 16 A)
EN 61000-3-11 (I > 16 A)
Compliance with the following standards requires coordination with the application/terminal device engineering team:
EMC measurements Standard Interference voltage (range 0,15 - 30 MHz) EN 55014-1 Interference power (range 30 - 300 MHz) EN 55014-1 Electrostatic discharge EN 61000-4-2