High-current test system

Short description

South-Eastern Finland University of Applied Sciences (Xamk) is purchasing AC High-current test system for temperature rise testing of power grid switchgear and control gear components according to this tender documentation. Equipment will be located to the Electronics 3K-factory in Savonlinna. The floor space available for the device in the laboratory is roughly 10m x 15m. Please note attachment "HighCurrent_Test_device_lay_out.pdf".

South-Eastern Finland University of Applied Sciences (Xamk) asks offers for the Electronics 3K-factory in Savonlinna about an AC High-current test system for temperature rise testing especially on LV and HV switchgear and control gear as well as transformer substation in accordance with IEC 60060 and IEC 62271.

It basically consists of a switchgear cubicle, regulating transformers and the high-current transformers. The capacitive compensation integrated in each high-current transformer is required to improve the power factor (cos phi) and thereby to minimize the input power rating of the test system. In addition, an automatic compensation unit in each cable loop minimizes the feeding power requirements.

The first sample (primary loop) is the test object and stressed with high current and high voltage at the same time according to IEC, because the cable conductor is heated inductively and therefore on floating potential. The heating current is induced by the high-current transformers where the cable sample itself forms the secondary winding.

The complete test system is controlled by the operating device. The control device allows easy programming of the load cycle procedure. The test results are saved in the PLC memory and can be transferred to the PC.

Main components of the AC High-current test system:

- 3 pcs. High-current transformers 6000-7000 A

- 1 pcs. Switchgear cabinet

- 1 pcs. Automatic compensation unit to improve the power factor (cos phi), total 200 kvar with 25 kvar steps

- 3 pcs. Single-phase Regulating transformers to regulate the voltage and current

- 1 pcs. Cabinet for measuring systems for currents and test object temperatures, set of temperature sensors

- 1 pcs. Control system with operator device, display, keyboard, remote diagnostics module and Web interface

- 1 pcs. Control firmware to control all functions

Main functions of the AC High-current test system:

- inductive heating test system which can operate in conventional operation mode (current-temperature-calibration without reference cable, only for constant temperature tests).

- compact design of test setup.

- fully automated test procedures for short- and long-term tests including data recording.

- easy operation: The system uses uniform control conception for all kinds of test systems. The operator knows the general operation principle and is familiar with it.

- protection measures to prevent over-temperature and logic controls for monitoring cycle state.

- automatic test interruption in case of non-compliance of test time or temperature.

- free choice of heating cycle parameters such as heating up time, time at constant temperature and cooling time.

- advanced computer-aided test system for fully automatic testing including data processing and test results saving to PC.

- AC high-current transformers of low noise.

- control system based on world-wide proven industrial components.

Power supply requirements

- Rated voltage 400 v

- Rated current/primary loop 300 A

- Rated current reference loop 100 A

- Duty cycle, continuous operation

- Frequency 50 Hz

Some other absolute requirements

- The warranty time is min. 2 years, the warranty covers all main components and control devices

- the capacity of the primary loop high-current level must be 6000 to 7000 A

- the system must fulfill European Union safety regulations and has to be CE-approved and marked