Semidan Power - UPS Systems, Chargers, Inverters and GPUs

Semidan Power is a 100% Danish owned engineering company, established in 1978. We develop standard and special Uninterruptible Power Supply (UPS) systems, chargers, inverters, frequency and DC / DC converters, and Ground Power Units (GPU).

UNINTERRUPTIBLE POWER SUPPLY SYSTEMS (UPS)

Semidan Power designs and manufactures UPS systems from 200VA - 4.8MVA.

All Semidan systems are controlled by an advanced power transistor technology - a Pulse-Width Modulation (PWM) inverter with high frequency switching, which ensures very low acoustic noise, low weight and small dimensions.

A modern UPS system consists of charger, battery, static inverter and static switch. In normal operation the charger maintains the charge condition of the battery. At the same time the charger supplies the inverter with DC voltage. Within the inverter the DC voltage is converted into a sinusoidal alternating voltage completely independent of the incoming mains and is therefore always stable with regard to voltage and frequency.

During mains failure, the inverter will still supply the load but now from the energy stored in the battery. The supply of the connected load will therefore be completely independent of mains failure(s).

ONE OR THREE PHASE CHARGER SYSTEMS

The charger is a static no-break system that can either be a thyristor or a switch mode regulated charger with galvanic isolation. It can also be a one or three phase system depending on customer specifications or the size of the load.

In each case the charger is adapted to the batteries and is, as standard, equipped with high discharge and low DC alarms.

The charger can also be equipped with a monitoring system that will monitor the charging voltage and test the capacity of the batteries at intervals decided by the customer. Alarms can be visual and / or by switches for remote alarms.

VERSATILE INVERTERS

Semidan inverters are manufactured up to 4MVA and are controlled by PWM technology. Any source of DC can be used as input, as long as it is within the specifications of the inverter, typically from +24V to +400V, +20% / -15%.

The output voltage will be single or three phase ±1% and the frequency will be ±0.5%, independent of input voltage and load.

CHARGERS AND INVERTERS BUILT TO CUSTOMER REQUIREMENTS

Semidan Power produces chargers with all input voltages depending on costumers application e.g. 3V × 115V, 400Hz; 3V × 230V, 60Hz; 3 × 400V, 50Hz. Output voltages of 24V, 36V, 48V, 60V, 110V, 220V and 400V (or as requested) can be produced and output currents vary from 10A to 2,500A (or as requested).

Chargers can also be constructed with voltage and / or current controlling for applications such as trains, ships, airplane engine testing, etc.

Inverters can be built to use any source of DC specified by the customer as input, as long as that source is within the specifications of the inverter.

All systems supplied for train applications, including chargers and inverters, have been tested for shock, vibrations and EMC according to customer's specifications and requirements.

MOBILE OR STATIONERY GROUND POWER UNIT

Semidan supplies various airports around the world with its 28V Ground Power Unit (GPU). It is available in 300A or 600A versions and can be mobile or stationery, making it ideal for both indoor and outdoor use.

Semidan's GPUs are user-friendly with low noise and their glass fibre canopy means that they are not affected by rust or corrosion. They are available in a variety of colours.