Selecting the right UPS system is essential for ensuring power availability for critical loads in any industry. From industrial automation to medical equipment, such as CT, MRI, Cath labs, or X-Ray, UPS is a necessary component of the critical power infrastructure. Additionally, it is a mainstay of Information Technology systems, providing backup and quality power to both data centres and small-scale offices. With multiple designs available in online double-conversion UPS systems, buyers must carefully consider the topology that best suits their needs. A few of the topologies are as follows:
- Transformer-based UPS
- Transformerless UPS
- Transformerless UPS with external input/output transformer
Based on the brand, the UPS models vary. In the first session, we will discuss the merits and drawbacks of UPS systems before examining the models of some of the top brands in the industry.
Transformerless UPS or transformer-free UPS utilise insulated-gate bipolar transistors (IGBTs), capable of dealing with high voltages preventing the need for a step-up transformer after the inverter. This enhances the energy efficiency of these uninterruptible power supplies compared to those that utilise a transformer.
With the improvement and progression of power electronic components, particularly the IGBT (Insulated Gate Bipolar Transistor), online UPS systems without transformers are beginning to be broadly utilised for UPS sizes of 300 KVA and below instead of the traditional transformer-based online UPS systems.
Deciding between a transformer-based or transformer-less UPS may not be as simple as it appears. When deciding on a UPS, it is important to consider many factors, such as size, efficiency and dependability. While these are the most crucial considerations, many elements must be considered before making a final choice. Now, we will discuss the different factors to consider when selecting a UPS.
Eliminating transformers from the UPS will reduce capital costs, however, they will still need to be included elsewhere within the data centre.
At capacities over 40 per cent, transformerless UPS efficiencies may be greater than some legacy transformer-based UPS. Don’t get caught up in efficiency modes, know your typical operating mode.
Since transformerless UPS systems have a smaller physical footprint, the cost of real estate must be included when considering their overall cost.
The transformerless UPS can be installed on a raised floor due to its lighter weight, resulting in reduced shipping costs.
The need for precision cooling of the power equipment may be reduced because the heat produced by the transformerless UPS is less.
Wide input voltage range of 138-485Vac (Phase voltage 80-280Vac) can be accepted with no derating when the input voltage is above 305Vac.
- A high input power factor can be up to 0.99.
- Three-level inverter topology, the efficiency can be up to 96%.
Flexible battery configuration
The battery count for each group is variable, ranging from 30 to 50 individual batteries that can be chosen based on specific requirements.
Strong load capacity
- The output power factor is 1.0, UPS can supply power to 100% unbalanced load.
- High adaptability for load, it can connect full inductive load or capacitive load.
Transformerless UPS systems are particularly well-suited for economical UPS solutions and IT/ICT infrastructure that utilises linear load characteristics. They are also ideal for use with CT imaging machines, MRI machines, and laboratory equipment that has linear load characteristics. In addition, transformerless UPS systems are a great choice for providing backup power for IT or CCTV loads.
Transformerless UPS systems utilise insulated gate bipolar transistors (IGBTs) to manage high voltages, thereby eliminating the need for large, costly, and noisy transformer components. With a smaller size and reduced weight, these systems are flexible and easy to install and transport, resulting in lower investment and operating costs. The implementation of IGBT technology in transformerless UPS systems results in significantly higher efficiency, up to 90-96%, making them an environmentally friendly choice.
However, since IGBTs have lower impact resistance, they are best suited for scenarios where the power quality requirements are not extremely high, such as the IT industry and small data centres. Moreover, transformerless UPS systems are the preferred choice for applications with ratings up to 120 kVA as they prevent excessive power supply while ensuring optimal operating efficiency.
If you have size & price limitations, then a Transformer-less UPS system may be a more suitable option.
Transformer-based UPS system
Transformer-based UPS systems use an inbuilt transformer to provide galvanic isolation between the rectifier and UPS output. Using this configuration, two different sources can be connected to the rectifier and bypassed without affecting the existing earthing system.
Advanced working mode
UPS systems adopt a Double Conversion online design that generates a pure sine wave output with frequency tracking, phase-lock, voltage regulation, and noise suppression. This design guarantees an uninterrupted and stable power supply, thereby preventing any power fluctuation interference, and offering comprehensive protection to the load being supplied.
The output provided by UPS systems boasts a zero transfer time, which meets the high standard power requirements of precision equipment. This feature ensures that the power supply is reliable and uninterrupted, thereby enhancing its reliability.
The filter utilised in UPS systems enhances energy efficiency, reduces harmonic pollution of the power grid, and lowers the running cost of the UPS. This filter also enhances the input power factor to 0.98, thus minimising wastage and maximising the efficiency of the system.
Full DSP Control
In addition to providing superior performance, digital control minimises risks associated with analogue malfunctions and ensures greater stability and dependability.
High output power factor
Using the output power factor, users can improve loading capacity and reduce investment costs by up to 0.9.
AC input voltage range is (380Va/400Vac/415Vac): +25%, thereby reducing battery use frequency and extending battery life.
Wide input frequency ranging from 45Hz to 65Hz, ensures stable operation of all types of fuel generators.
Optimisation of high-performance battery
Adapt intelligent battery management (ABM) technology, which extends battery life and reduces maintenance requirements.
Advanced floating switching and charging technology maximise battery activation, saving charging time and extending battery life.
According to battery intelligent management, the system detects the discharge current and predicts the discharge time when the battery discharges. Thus it informs the users to take the appropriate measures.
To detect battery issues early, set the start time and duration of the self-test according to the different periods (monthly or weekly) for the battery self-test.
When the reliability and stability requirements are higher, transformer-based UPS systems are recommended for financial, transportation, data centre construction, and industrial applications, such as steel, oil, and metal industries.
Transformer-based, also known as Semi Industrial, UPS is used mainly for Cathlab Machines, MRI Machines, X-Ray Machines, etc. It is also used in laboratory equipment where the load is non-linear, in robust environments, UPS for highly critical loads, UPS for packing plants, UPS for automation plants, UPS for factories, and UPS for central UPS solutions.
In conclusion, transformer-based UPS and transformerless UPS systems have unique benefits and drawbacks. Transformer-based UPS systems are generally more robust and reliable, making them ideal for essential applications requiring high-security levels against power disturbances. BTLME, as the leading UPS Suppliers In Dubai, help you make an informed decision and ensure that you choose the right UPS system to meet your needs. We also offer a comprehensive range of products and UPS repair services, including regular maintenance, battery testing and replacement, and emergency response, to help customers avoid UPS failures.