Grid interferences due to the increased use of power-electronic systems can ‘pollute’ the network with currents that deviate from the sinusoidal shape due to the
switching principle of the used IGBTs or thyristors. The fluctuating supply of electrical energy due to the increasingly decentralized energy generation additionally
aggravates the impairment of power quality in the supply grid. A bad network quality and stability can damage sensitive electronic devices, cause unwanted plant
downtimes by protective shut-downs or lead to unnecessarily high energy costs. The ibaPQU-S module in combination with the ibaPDA process data recording is capable of constantly monitoring the grid quality and contributes to enhancing it.
The iba power quality measurement system is suitable for plants used in steel- or rolling mills or paper machines which are all large energy consumers. But also the
operators of HVDC systems or systems for reactive power compensation belong to the target group. In case the iba system is already in use as transient fault recorder,
the measurement of power quality parameters can simply be added to the TFR functionality.
The ibaPQU-S module unit is a central component of a measurement system which samples net-synchronously raw values like current, voltage and frequency and calculates internally in compliance with standards the characteristic values that are relevant for the grid quality: RMS- and peak values, flicker, crest factor as well as
harmonics and interharmonics, phase shift or harmonic distortions. Hence, power flows and events, which influence the grid quality and the whole grid dynamics, can be analyzed. The ibaPQU-S is suited for DC networks, for networks with 50 Hz or 60 Hz and for the railway network with 16.7 Hz.
The ibaPQU-S module is easy to integrate into a superimposed process and plant monitoring system. The calculated network quality parameters are transmitted via a fiber optic connection to the ‘ibaPDA’ process data acquisition system. There, the time-synchronous process values are aligned by resampling with the net-synchronous power quality values. The measurement values of current, voltage and frequency can be analyzed along with the general plant and process data. In case of fault events, alarm messages can be issued.
"With ibaPQU-S, the relation between the operational state of the system and specific changes in the network can be detected. This forms the basis for a root-cause analysis for grid interferences due to the production process," explained Dr. Andreas Quick, head of the product management at iba AG.
The net-synchronous sampling with ibaPQU-S determines the characteristic values of the standard EN 50160 based on the provisions provided by the standard IEC 61000-4-30 according to class A. The module can be used for contract-related measurements for accounting purposes.