22 / 09 / 2020 2705 Views
  • Product news

1. Overall dimensions

It has the smallest overall dimensions in the world! In more technical language: Triol AT27 has the best ratio of footprint/power rating - approx. 30% lower than other manufacturers of medium voltage frequency drives. In addition, all the ED line (indoor usage) models provide single-end service, which allows the VFD to be placed directly "under the wall" without an additional passage for safe use.

The single-end service allows you to save 25-30% of the usual VFD installation space, building materials, and labor costs in newly built areas. For example, when creating a new installation space for a 2500kW 6kV variable frequency drive, AT27 will save the customer about 3 square meters.

You can often place Triol AT27 where other VFDs don't fit. This advantage allows our partners to offer customers a unique solution with no extra costs for a separate shelter and power cable.

Read more about this benefit in the article: Triol AT27 ED has the smallest dimensions in the world among variable frequency drives of its class!

2. Enclosures

The range of Triol AT27 enclosures operate in most climate zones (except for the Arctic climate) and industrial environments (except for explosive conditions). We are the only manufacturer of medium voltage VFDs globally with NEMA4 and NEMA4X enclosures that can be used on offshore platforms without additional shelter.

Outdoor models don't have the extra costs required to provide the necessary environmental conditions for the VFD operation, as is required by most inverters from other manufacturers. Three lines of Triol AT27 - RX, MV, and DD - can be operated outdoors.

This leads to significant cost savings when using Triol AT27. For example, to install a 2500kW 6kV variable frequency drive which isn't specially designed for the environmental conditions, you would need a shelter with an area of at least 17 square meters, at a cost tens of thousands of US dollars, plus a climate control system. Ultimately, Triol AT27 will save the buyer tens of thousands of US dollars.

3. Transformers

We exclusively use transformers of our own design and production in Triol AT27. In these we use UNICORE technology, which has reduced the excitation current of our transformers by three times in compared to the step-lap technology used by most transformer manufacturers. We determine and control the electromagnetic and thermal parameters of the transformer, which allows us to optimize and not to oversize transformer dimensions and power rating. In the basic version, Triol AT27 has four high-voltage winding taps, which allows the VFD to be maximally adapted to the customer's mains.

As a comparison, in variable frequency drives with a power of 1600kW, 6kV, most manufacturers use a serial transformer with a 2000kVA rated capacity, while Triol offers an optimal transformer with an 1840kVA power rating while maintaining a low level of power losses. At the same time, the buyer does not overpay for the transformer and its oversized cooling system.

Such an advantage also allows the user to run complete diagnostics of the transformer according to the instructions adapted to a specific VFD, receiving an online consultation on diagnostics and repairs directly from one manufacturer. It significantly reduces the equipment downtime (by up to 3 days in our experience). The technical solutions of the transformer provide the possibility of repair directly on-site without having to take it to the manufacturer.


4. Simple first start-up

Triol medium voltage VFDs are the only ones in the world that allow commissioning from a web browser via Wi-Fi. We view the ease of AT27 start-up as a significant competitive advantage, on which we work continuously. We have ideas on how to make this process even more accessible, more reliable, and faster.

It's not just that a computer screen is larger than the controller screen of the VFD itself, or that a mobile screen fits conveniently in your hand. The fact is that the Triol Wizard on your desktop or your mobile phone unmistakably directs the actions of your team directly to the desired result, making it impossible to skip a step or perform it incorrectly. The checklist after each stage of adjustment is carried out automatically by the Triol AT27 itself, and you can see the results on your screen immediately.

This allows our users to carry out a step-by-step start of the VFD in just 10 minutes, in 20 steps. It helps to reduce the commissioning time and to avoid mistakes during commissioning. Of course, this is only possible after the fulfillment of assembly operations. In the next section, you can see how to ensure the error-free installation of Triol AT27.

Read more about this benefit in the article: Guaranteed and quick start of the Triol AT27 variable frequency drive: Triol Wizard magic

5. Full adjustment and preliminary diagnostics before high voltage supply.

Medium voltage power cells for Triol AT27 VFDs are organized by input transformer (a separate winding for auxiliary power supply) or by a different connection to a low voltage (380, 480V) auxiliary power supply. If the customer can provide power for his own needs, he can get the Triol AT27 model with the relevant circuit.

In this case, the risk of equipment failure will be minimized on first start-up after installation work at the facility or after maintenance or repair. 100% of the VFD elements can be tested with low voltage, which, in case of installation errors or other malfunctions, will not lead to a VFD failure.

This allows for the installation contractor to guarantee the correct installation of the equipment and to confirm the readiness of the VFD for start-up without a high voltage supply. The customer can accurately plan the completion of commissioning and the timing of maintenance and repairs.

One of the common mistakes during commissioning is the incorrect connection of power feed cables. This leads to a failure in the VFD and power cell damage. Potential losses in the case of power cell damage to a 1600kW, 6kV variable frequency drive amount to several thousand US dollars, and additional days of waiting and repairs lead to delays in the commissioning of essential and powerful facilities, more hassle, and extra-budgetary expenses. Eliminate these risks by going through a preliminary diagnosis before applying a high voltage.


6. Optimal solutions for AT27 integration

Triol Corporation supplies not only high voltage variable frequency drives but also equipment that makes it easy and inexpensive to integrate AT27 at the operation site. Often, the customer doesn't have the opportunity to select a different connection point for connecting AT27 to the grid or doesn't have the chance to solve the problem of switching several motors within the existing switchgear.

For these purposes, we offer a line of specialized switching cabinets, Triol СВ27, which allow you to implement any combination of switching on both one and several AT27 VFDs together with several motors in various combinations of power supply circuits for consumers and the operation of units.

In this case, AT27 turns from a variable frequency drive into a customized set of equipment that fully meets the requirements of the end customer.

The advantages of this solution are:

  • up to eight switching devices in one cabinet 1000mm wide (contactors, disconnectors, earth switch), compared to standard mission equipment package and an outgoing section with 1-3 switching devices at a commensurate price
  • the presence of a built-in programmable control unit that provides a plug and play connection to the AT27, making it possible to do without an external PLC (programmable logical controller), which is responsible for operating with switching equipment.

For example, when implementing a solution for frequency control and the immediate start of one motor, only one СВ27 switching cabinet is required, instead of three traditional standard switching boards. Using CB27 switching cabinets can lead to savings of several thousand US dollars.

7.Faultless transmission of drives to the curved grid, and pick up from the grid

The importance of synchronous transfer of the mechanism to the grid is evident to everyone. You can find solutions everywhere that don’t have an algorithm for synchronous transfer to the grid. It leads to periodic shutdowns of switchgear sections (due to 12-fold starting current), creates mechanical shocks to the motor and the operating mechanism during the transition process in the engine while connected to mains. These problems are removed with Triol's unique algorithm for synchronous, unstressed transfer of the motor to the grid and back from grid to the VFD.

The advantages of this solution are:

  • absence of current in-rush to the grid when the motor is connected
  • absence of mechanical shocks on the operating mechanism at the moment of connection to the grid
  • no strict requirements for the grid quality
  • no current pause (loss of torque of the mechanism) when the motor transfers from the grid to the VFD.

Such solutions avoid the unauthorized shutdown of switchgear sections whilst the motor is connected to the grid and damage to operating mechanisms, which would be expensive to repair.

8. AT27 operation in case of voltage sags

A weak enterprise grid or voltage sags in the energy system cause problems for our competitors. But not for Triol AT27! It implements a special kinetic buffering algorithm, which ensures the continuity of the technological process in the event of symmetrical and non-symmetrical voltage sags to a complete loss of voltage. The operating time in this mode is determined by the inertia of the load and can range from 100ms to several minutes (until the motor stops).

It looks fantastic: the machine power supply stops, sometimes for seconds, and although the mechanism is quite powerful, it continues to work! But this is not a miracle; this is physics. To continue the operation of the mechanism, we use part of the kinetic energy previously accumulated both in the motor and in the mechanism itself and we ensure their performance with a unique Triol algorithm. When the power is restored the VFD resumes its regular operation, imperceptibly for the mechanism (without mechanical shocks, sudden changes in frequency, and current surges).

"Genius is simplicity," but the savings and benefits from it are huge!

9. Power cells HOpCoDTM bypass

Some companies have a mechanical bypass, and some have an electronic one. The truth is that both have disadvantages. The HOpCoDTM Triol bypass, an electronic-mechanical bypass developed and patented by Triol Corporation in 2018, incorporates the best from both types of bypass, with no drawbacks.

As a result, Triol AT27 with HOpCoDTM cells bypass ensures the continuity of the technological process in the event of failure of the AT27 power cell until the planned switch-off of the equipment.

In this case, bypassing occurs at a speed that meets those requirements which are most sensitive to the continuity of the power supply mechanism (<4ms). Such mechanisms include centrifugal pumps, ball mills, and others.

10. Ventilation change-over

If any fan in the VFD cooling system fails, the AT27 is fully operational, without restrictions. Replacement of a failed fan is possible whilst running; it`s not necessary to stop the VFD.

These AT27 features avoid loss of resource and profit, spoilage of raw materials, and semi-finished products. There are no emergency shutdowns while normal parameters of the power supply system are restored after starting powerful mechanisms, failures on power lines, and internal VFD faults.

This is especially important at such facilities as power plants, metallurgical plant foundries, chemical plants, and oil refineries, where a short-term shutdown can lead to long-term restoration of the technological process and losses.

11. User Experience (UX)

Triol has developed UMKA37, combining a PLC with an integrated touch screen to customize the user interface for the type of customer mechanism. It allows you to control 100% of the mechanism parameters and to design effective process control.

Benefits for the user:

  • Ergonomic interface verified by 25 years of experience in the development and implementation of variable frequency drives (doesn`t require training in operating variable frequency drives)
  • Provides warnings when preventive VFD maintenance is needed (minimizes emergency shutdowns, minimizes repair and maintenance costs)
  • Fast and unambiguous identification of the problem (reduces the time and resource costs for finding technical issues in the VFD and external equipment).

For example, in case of an emergency shutdown of the reservoir pressure maintenance pump with an undetected cause, the time for a comprehensive survey and identification of the reason may take at least three days. With the UMKA37 controller, you don`t need to waste time on this at all! With each day of operation of the Triol AT27, customers like it more and more, thanks to its interface and accurate status information!

12. "Gentle work" with the motor windings

Triol medium voltage variable frequency drives have the best dV/dt for multilevel voltage VFDs in this device class. Our dV/dt level on the windings of a running motor doesn`t exceed 45-50V/μs, made possible by a special PWM algorithm with suppression of step voltage fluctuations in a long cable line on the motor side.

This allows the AT27 to be used with any type of motor without using sine filters and dV/dt filters, which saves about 5-10% of the VFD purchase cost without reducing the service life of the electric motor.

Insulation damage and turns in the frontal parts of the stator windings of an electric motor with a high dV/dt frequency drive output voltage will sooner or later lead the user to repair a medium voltage electric motor.

13. Proprietary vector control

Triol AT27 software products provide vector control of a wide range of electric motors: asynchronous, synchronous, and permanent magnet motors. Triol is the only manufacturer of medium voltage frequency drives with vector control of submersible permanent magnet motors.

This allows users to:

  • Apply the same AT27 range of commodities for both scalar and vector control, using different software packages
  • Control different motors at one site, from one VDF: asynchronous, synchronous, and permanent magnet motors.

For example, if asynchronous and synchronous motors requiring vector control are operated at the users site, then installing one AT27 won`t require the synchronous motor to be replaced with an asynchronous one.

14. Reliability and durability

Triol AT27 power cells use polypropylene capacitors. Their MTBF (mean time between failures) is 100,000 hours (over 11 years). MTBF is the most expensive element if the product (the transformer) is more than 25 years old. Triol AT27 has a total MTBF of at least 62,000 hours, without replacing components, which is higher than that of variable frequency drives from other manufacturers.

The long average time between failures allows you to reduce the amount of downtime and repair of the VFD and reduce the VFD cost of ownership.

As an example: most manufacturers use electrolytic capacitors with an operational life of 3 years in their power cells, which will require 3-4 replacements of capacitor banks over 11 years, while with AT27, only one such replacement will be needed. Over 11 years, the difference in replacing capacitors for 1600kW, 6kV inverters will amount to approx. $30,000.

The reliability of Triol AT27 VFDs is close to 100%, and we continue to work both in terms of increasing the reliability and in terms of increasing the durability of the solutions used in products, including through full load tests. We achieve this by, amongst other things, carrying out load tests of all manufactured variable frequency drives for rated power and overload capacity.

The tests are carried out using a unique patented technology that allows testing both 160kW drives and 8MW VFDs and more.

Dear reader, we invite you to see for yourself factory acceptance testing of our VFDs under full capacity.

In conclusion, we are pleased to note that we see new opportunities to make Triol AT27 the undisputed leader in its field, not only today but also in the future. Over the next 14 weeks, we plan to post additions to this article. Each additional paper will be devoted to one of the listed advantages. We will provide comparative characteristics with our direct competitors, as well as the results of measurements and tests that will allow you to be sure that Triol AT27 is indeed the best medium voltage variable frequency drive in the world.

In addition, during this time we have planned several unique implementations in different countries, on different continents, which, we are sure, will be relevant to our professional readers. We look forward to telling you about them; it will be interesting! Join us!

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