IGBTs / HGÜ / HVDC - New Challenges for Test Engineers

SATURN HV probe with data transmission via fiber optic cableThe continuous growth of renewable energy use presents numerous challenges for the energy sector. High Voltage Direct Current Transmission is one of the key technologies that will need to be used to restructure the current power networks. HVDC allows a low-loss energy transfer over long distances between energy producer and consumer while minimizing the environmental impact which cannot be completely eliminated. It also provides a simpler solution for coupling unsynchronized AC power grids (i.e. in Smart Grids). In order to evolve this young technology to its full potential, tailored hardware and software for high power applications is required.

The SATURN Transient Recorders from AMOtronics have been optimized specifically for this kind of applications. They provide hardware and software solutions which simplify the everyday work of test engineers and allow faster and more accurate results. The SATURN device family enables high precision measurements of electric signals in a wide range from a few kHz up to GHz. SATURN measurement satellites connected via fiber optic transmission lines make it the ideal choice for high voltage and high current applications (see box).

Engineers can choose between different housings equipped with various modules for input, output and triggering as needed for the specific test application. This allows lightweight mobile systems as well as high channel count 19" rack-mount solutions. The input modules are highly configurable and can be connected to nearly any kind of sensor, including HV probes and Rogowski coils. A new member of the AMOtronics product portfolio is the SATURN Sequencer. This device allows it to precisely control test facilities as used in low, high and medium voltage laboratories around the world (see box).

In addition the Saturn product family includes the proven SATURN Studio II software. Its field-tested user interface makes it very easy to configure the hardware, define signal triggers and perform measurements. In addition the software provides numerous integrated functions for data analysis and report generation. The software also offers interfaces integrate external devices from other vendors. This allows the use of existing older test equipment in parallel to the Saturn system under the same modern user interface.

The Saturn Studio II Professional Edition further extends the flexibility of the software. It allows engineers to automate recurring tasks themself, from data acquisition up to generating a customized PDF report or printout. If needed, engineers can design their own user interfaces which will guide the end user step by step through the test.

With AMOtronics customers gain a one-stop source for trusted measurement equipment, individualized support and training as well as custom designed hardware and software for specific test applications.

Precise Control of HV Test Facilities

During measurements in a high voltage or high power test lab often switches, contactors, relays, IGBTs and MOSFETs must be controlled in a specific timed sequence. This task now can be solved easily with the new SATURN Sequencer from AMOtronics.

The Sequencer can be used either as a stand-alone device or integrated into a SATURN Transient Recorder. The SATURN Sequencer offers 16 digital outputs, which can be provided in groups of 8 either as BNC or fiber optic outputs. The latter provide a fault-resistant insulation against high voltages and currents and enable the bridging of greater distances to the test facility.

The program for controlling the outputs can be created using a convenient user interface within the SATURN Studio II software. In addition to a pure sequential processing also loops and case statements (branches) are supported. If needed analogue signals measured by means of a Saturn transient recorder can be monitored and used to respond instantaneously to any event.

The outputs are being controlled with an accuracy of 10ns either via an internal clock or in AC applications synchronized with the generator frequency (16 2/3Hz, 50/60 Hz, 400Hz etc.).

Safe Measurements at High Power

Performing tests in hazardous environments, as for example in high-power experiments, represents a special challenge. Usually a fiber optic transmission line between the sensors and the measuring system is used in order to protect the personnel as well as the test equipment.

This means that the measured signal is acquired, digitized and optically transmitted. In order to be able to use a common oscilloscope or measurement device, it is common to convert the digital signal back to an analog signal on the other side of the transmission line. However, this re-conversion results in additional noise and a loss of precision.

Using a SATURN base unit connected to SATURN satellites via fiber optic lines solves this issue. The digitized signal data which is transmitted via the fiber link will be directly stored into memory without additional re-conversion. This allows highly accurate measurements even in dangerous environments.

In addition the SATURN Studio II software offers specific modules for standardized data analysis and reporting (IEC 60060-1, IEC 60060-2, IEC 61083-1, IEC 61083-2, STL etc.), creating reliable results while also saving time and money.