西门子S7-1200*处理单元CPU1211C

西门子S7-1200*处理单元CPU1211C

西门子电缆代理商

One of the core objectives of the European Union is a sustainable power industry. In industrial plants today, around 70 % of the power demand is from electrically driven systems. This high percentage contains huge potential for saving energy in electrical drives. For that reason, the European Union introduced minimum re for the energy efficiency of electric motors in the form of a statutory motor regulation as early as 2011.

These activities are expanded by EU Directive 2019/1781, which deals with more stringent re for DOL motors (Direct On Line) and defines the efficiency limits for frequency converters. The directive offers a legal basis for technical content in terms of the efficiency of specific products and services. However, standardization plays a leading role in determining the range and available market technology.

Improving energy efficiency is supported by a systematic selection of the most efficient converter and drive system technologies on the IEC 61800‑9 series of standards. Part 1 specifies the methodology to determine the energy efficiency index of an application on the basis of the expanded product approach (EPA) and semi-analytical models (SAMs), whereas part 2 entails indicators for the evaluation of the energy efficiency performance and classification of converters and drive systems.

First of all, the consideration of eight application-relevant operating points is introduced as mandatory, in order to take the different applications into account in a targeted manner. Determination of loss values at these eight points and definition of efficiency classes are laid down by the standard in a uniform way. This enables data relevant to operation, such as application-specific load profiles, to now be taken into account more easily in the energy efficiency analysis.

The standard is especially important for variable-speed drives of the following types:

for AC/AC converters without energy recovery functionality

for motors with integrated converters

for supply voltages of 100 V to 1000 V

for power ratings of 0.12 kW to 1000 kW

To cover all applications of driven machines, the IEC 61800‑9‑2 standard defines operating points in full-load and partial-load operation, at which the losses of the motor and drive systems have to be determined. Based on the loss data at the operating points in partial-load operation, variable-speed drives can be explicitly considered in more detail. This makes their advantages especially clear.

Duty cycles for different driven machines