Sinusoidal filter for increasing the efficiency of inverter-controlled motor systems

TRAMAG products explained

Sinusoidal filters or LC filters consist of a (choke) inductance (L) and a downstream (capacitor) capacity (C) and form a low-pass filter tuned exactly to the required resonance frequency. Just like dU/dt filters, they belong to the output filters, as they are also operated directly at the inverter output and before the connected drive units (motors). They are individually developed and optimised for the clock frequency of the inverter.

The name sinusoidal filter is derived from the sinusoidal output voltage. While dU/dt filters mainly reduce the rates of voltage rise, sine filters smooth the square-wave voltage pattern at the output of the frequency inverter to a sinusoidal output voltage. This arises from the PWM (pulse width modulated) signal due to the low-pass effect.

Among other things, this dampens interference pulses, voltage peaks, additional losses on components such as cables, lines, noise developments, insulation stresses on motors accordingly and increases the efficiency and service life of the entire drive system.

Our sinusoidal filters are mainly used in drives and automation technology. Customers from all over the world have been relying on TRAMAG’s high-quality wound goods for their frequency converter-controlled motor operation for years.

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Sinusoidal filters for drives and automation technology!

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Always up to date in transformer technology

20. December 2023

Christmas & New Year Greetings

The TRAMAG Team would like to thank its customers, business partners and friends for the trust they have placed in us and for their cooperation in partnership over the past year. 2023, another year full of business challenges, but also a year of suffering and misfortune for many people in regions near and far around the world.

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18. December 2023

Quality is when your QMB goes “High-Five-S” with you

We know where quality must ultimately be demonstrated and proven: In the product, in the customer’s application. But where does quality begin? On the one hand in technical development and on the other hand in the organization of workplaces in production. Employees who keep their workstations tidy maintain an overview, have access to the right tools at all times and can work on the product efficiently and with quality assurance.

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13. December 2023

Information visit to TRAMAG by the VDI District Association of Bavaria North-East

On the afternoon of St Nicholas’ Day, the TRAMAG plant in Fürth hosted an information event for members of the Association of German Engineers (VDI) from the Bavarian North-East District Association. Due to the regional proximity and also taking TRAMAG’s 100th anniversary as an occasion, we received a request from the Nuremberg VDI local group to visit our plant, which we were very happy to fulfil.

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6. December 2023

“Quality is when the Customer comes back and not the Product”

The most technically innovative or economically attractive product in an application is worth nothing if the quality is not right. Not only would the failure of the product itself have to be lamented, but possibly also further damage to the entire application.

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22. November 2023

TRAMAG Interview with Easy Engineering Magazin

In a recent interview with Easy Engineering magazine, Jan Reinecke, member of TRAMAG’s management board, presents TRAMAG’s business activities and innovative products and provides current and exciting insights into relevant market trends.

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