KoCoS Blog

A network calculation is always necessary when new networks are created or planned, existing networks are revised or new plants as well as consumers have to be integrated into existing networks. Especially in the case of existing networks, a reliable simple statement about the utilization of the network is not easily possible in many cases due to the insufficient data situation. The structures, which have grown over the years, are usually only documented schematically and were, if at all, considered mathematically in parts during refurbishments.

As a result, the security of supply can be endangered. In order to ensure security of supply, it is absolutely necessary to know the load and disconnection conditions in one's own network. These data serve as a basis for the design of network changes.
The network calculation serves thereby:

  • To support the network operation in the evaluation of the current network condition (ACTUAL condition).
  • To support secure network operation by means of forward-looking network simulations (planning basis).
  • As a basis for operational and network expansion planning (TARGET condition).
  • In detail, the network calculation records all dimensioning and calculation data for the correct dimensioning of the electrical power distribution, such as:
  • Utilization of the resources by load flow calculation,
  • Determination of the capacity reserves of the individual resources,
  • Short-circuit current calculation,
  • Voltage drop calculation,
  • Selectivity consideration
  • Current carrying capacity,
  • Protection against overload,
  • Protection against short circuit,
  • Protection against electric shock by disconnection.

In the planning phase of an electrical switchgear or an electrical network, the network calculation is an essential tool for the correct design and the correct selection of the electrical equipment. After completion of the installation, the network calculation is used to determine the setting values of the protective devices or for the required proof of selective fault disconnection (selectivity) in accordance with the applicable standards. The testing of the individual protection devices can of course be carried out with our protection relay testing system "ARTES".

The KoCoS Engineering & Services team uses the established and manufacturer-independent network calculation program "PowerFactory" from DigSILENT. Hereby we calculate nationwide for our customers’ medium and low voltage networks in the automotive industry, industrial and public network operators, public state and federal properties and the petroleum industry.

The European power grid dealt with major problems on 08 January 2021. An entire region in Eastern Europe was disconnected, and in some cases experienced power outages. The European power grid is part of the critical infrastructure (CRITIS). The Austrian Federal Army had already warned in January 2020: "A Europe-wide blackout is to be expected within the next 5 years!“
On 8 January 2021 at around 14:05, a frequency deviation of around 250 mHz occurred in the synchronized European high-voltage electricity grid. As a result, the region of south-eastern Europe was disconnected from the European interconnected grid.

A cascade of failures of equipment, such as power lines and switchgear in south-eastern Europe, led to massive problems within the European power grid. According to the report, the near-blackout in large parts of Europe was triggered by a transformer station in Ernestinovo, Croatia. Initial investigations stated at 14:04 an overcurrent protection device on a 400-kilovolt bus bar coupler in the substation tripped, causing it to switch off automatically. This also interrupted two extra-high voltage connections that carry electricity from the Balkans to other parts of Europe; affecting the lines to Žerjavinec (Croatia) and Pecs (Hungary) in the north-western direction. The result was that within less than 50 seconds the European power grid split into two areas: the northwest, which lacked 6.3 GW of generation capacity, and the southeast, which had a corresponding surplus.

In some regions there were visible problems. For example, lamps in households and on the streets have lit up or went out, and electrical appliances turned on and off. The radio station RFI România reported power cuts in parts of Romania. The frequency drop led to consequential disturbances at various infrastructure operators, such as the Vienna airport and hospitals, which triggered the emergency power supply. There was also a serious incident at Vienna Airport, where hundreds of hardware parts were destroyed and damage amounting to several hundred thousand euros was caused. Approximately one hour after the disconnection, the two power grids were resynchronized.

Exact sequence of the disturbance
At 14:05 (CET) the frequency in the north-western power unit dropped to 49.74 Hz. After about 15 seconds, it stabilized at 49.84 Hz, which is still within the permissible band for deviations of plusminus 0.2 Hz. At the same time, the frequency in the south-eastern area jumped to 50.6 Hertz before stabilizing at a value between 50.2 and 50.3 Hz.

The disconnection of the sub-grid had a clear impact on the grid frequency. Thus, at (14:04:55 local time CET), the grid frequency dropped from about 50.027 Hz to a minimum of 49.742 Hz within 14 seconds. This left the normal control range of 50.000 Hz ±200 mHz. The first stage of the schedule (activation of power reserves) was achieved. Reconnection to the interconnected grid at 15:08 CET, on the other hand, had no effect on the grid frequency.

Reduction of product recalls and costly image damage through the new product feature ejector monitoring at INDEC 300 systems

Avoid product recalls even before the goods leave production - with the reliable vacuum inspection systems from KoCoS.

With our INDEC range of vacuum inspection systems, food manufacturers have the assurance that HACCP (Hazard Analysis & Critical Control Points) principles are met.
KoCoS vacuum inspection systems are characterised by their superior detection sensitivity and automatic rejection of defective products in the food industry.

The ejector monitoring function checks whether the ejector has separated a container from the product flow that has been detected as bad. For this purpose, another light barrier is arranged parallel to the conveyor belt opposite the ejector. If the light barrier is not interrupted by the bad container within the adjustable delay after the ejector has been triggered, an error message is generated.

Call up the Edit Ejector screen - tap the Monitoring button, set it to ON and enter the manually determined delay. In addition to the error message, an electrical switching signal can be output via a binary output, for example to stop the production process automatically.

The costs incurred by executed recalls, such as publication of warning messages, transport back to the factory and loss of sales, are relatively easy to calculate. But the more far-reaching consequences of the action, such as the loss of brand image among supermarkets and consumers, are not so easy to foresee.

It is precisely under these conditions that smaller manufacturing companies focus on vacuum testing systems from the INDEC series to minimise the risk of product recalls. It is also a way of signalling to the authorities and their trade customers that they meet the required standards and are available for lucrative new markets.

In food manufacturing, a good reputation is particularly important. The less often improperly sealed bottles and jars reach the consumer, the better. Only in this way can manufacturers protect the image of their brand, increase sales and secure their profits.

More and more small and medium-sized enterprises are realising that the best way to achieve these goals is with an INDEC series vacuum inspection system from KoCoS.

When you integrate an INDEC vacuum inspection system into your process, you can be confident that you are meeting current HACCP requirements and that your reputation and customers are reliably protected.

Multifunctional three-phase signal generator

With the EPOS 360 current and voltage source, KoCoS Messtechnik AG offers a signal generator that is recommended wherever maximum performance and the highest signal precision are required.

EPOS 360 has four voltage and three current signal sources. The signal curves are output via electronic power amplifiers. The parameters amplitude, phase angle and frequency can be varied over a wide range during the output.

Intelligent amplifier technology and synthetic signal generation make it possible to output any signal forms over a wide frequency range or even to play complex transient signals.

The TRANSIG monitor, included in the scope of delivery of the EPOS operating software, enables the graphical display and output of recordings that are available in SigDef format or in the standardized COMTRADE format. The corresponding signals are "played back" by EPOS as a transient sequence during tests.

In addition, the EPOS operating software contains a signal editor which enables the parameterization and calculation of any signal characteristics. These can be generated from a basic function, e.g. a sine and its superposition with one or more superposition functions, such as a DC component, exponential functions, harmonics, etc.

For special requirements, such as use in test benches, there is also a simple programming interface. This can be used in COM/ActiveX-supporting as well as in .NET environments.

For more information on EPOS 360, please visit the homepage. Ask our sales department for a quote.

Create ACI codecs yourself....

Enabling users to create their own codecs for their own needs was a requirement we placed on our latest ARTES innovation. The necessary basic knowledge of program development, especially in processing files, is already available to many users. Not much more is needed!

...or have it created by the specialist

Should the required skill be absent or short on time, KoCoS and its partners are ready to help. In cooperative collaboration, the required information and a sample file can be worked out by the user, and the KoCoS specialists will then take care of implementation. The codec created is then included in the standard so that it is available to all users.

Insight into the "secrets" of codec creation

As already described in the previous article, the ACI codec can be used to transfer any settings from an external file into the ARTES 5 software. ACI Codec is a collective term that summarizes different programs, the codecs. A codec is always adapted to a certain format of the source file. Since the source file can have any format, the complexity of the codec generally depends on its structure.

Preparations

Since a codec maps the parameters of an output file to the parameters of ARTES 5, it is recommended to first define the links in the form of a table. Any necessary adjustments or conversions of the parameters to be read in can also be entered. These are then implemented in the codec itself.
 

Creation of an Empty Codec

A C#-project can be created automatically from within ARTES 5. This provides methods and properties on the basis of which the ARTES software can be parameterized. The structure of the created project automatically provides the possibility to read any file. 

Assignment of parameters

Since the concept of ACI-Codec is based on the principle of object-oriented programming, the basic structures of ARTES 5 could be mapped as far as possible by the methods and properties. This enables a similar procedure to be followed when creating a codec as when creating a test object in ARTES 5.
To show the basics of creating a codec, static values are assigned to a test object in the following example. For a mature codec, these must be replaced by variables and linked to values in the source file.  
As in ARTES 5, a new test object must first be created. Afterwards the parameters of the test object can be provided with the corresponding values. Depending on the integrated development environment (IDE) used, the Intellisense function simplifies this process considerably.

The created parameter is now assigned values for the "General Information" and "Rated and Limit Values". 

Elements such as functions and the characteristics they contain must be added to the test object in the software interface before values can be assigned, the same procedure is followed in a codec.