DS-JUN22-PG51_Layout 1 20/06/2022 10:18 Page 1
DRIVES, CONTROLS & MOTORS vsd benefits
While a fifth of UK industry’s electricity bill is typically attributed to the production of compressed air, a substantial portion of the
W
ith the latest advanced solutions, compressors with VSD+ specifications are capable of achieving savings of up
to 50% of their energy requirement, plus total functional reliability and smart communication. So how is a VSD compressor different from a conventional fixed-speed unit?
VSD V fixeD-SpeeD compreSSorS
An air compressor with VSD automatically adjusts the compressor’s operating speed to match the production of compressed air to the demand in real-time. By varying the speed of its drive motor as air demand decreases, the VSD lowers the delivered airflow and power consumption. VSD compressors are designed for applications where demand for compressed air fluctuates. A fixed-speed air compressor operates at
the same speed whenever it is running and can only be stopped and started a certain number of times within a given time frame. It always draws the amount of power needed to meet the maximum compressed air demand. Because the speed of the motor cannot change, whenever the demand for air fluctuates instead of stopping the compressor it will be unloaded, throttled, and an air inlet valve will adjust to allow either more or less air to flow out. A VSD air compressor can operate anywhere in
the range between its minimum and maximum speed. When demand increases, the motor speeds up; when demand decreases, the motor slows down. This saves energy. Where VSD makes sense: When demand
fluctuates significantly between jobs, when demand varies by shift, on weekends or seasonally, or when manufacturing processes require tight tolerances for operating pressure. Where fixed speed makes sense: when the
demand for compressed air fluctuates very little, it is worth noting that variable speed drive compressors are not necessarily appropriate for all industrial applications. If a variable speed drive compressor operates continuously at full speed, the switching losses of the frequency converter can result in lower energy efficiency than an identically sized fixed speed compressor.
how DoeS VSD work?
Automatically adjusting the speed of the motor to match the air demand allows the pressure band of the system to be maintained within narrow tolerances. The motor speed of the compressor is regulated by frequency conversion, which results in the variation of airflow. With advanced electronic controls, the
delivery pressure is kept within a 0.10 bar pressure band, rather than the conventional 0.68 -1.03 bar pressure band used on inlet controls for non-VSD equipment. So, a lower
generated power dedicated to its production is energy wasted. That is why over 25 years ago,
Atlas Copco was the first to introduce VFD/VSD technology in its screw compressors
air compressor delivery pressure can be used to maintain the system's minimum working pressure, resulting in increased energy savings and lower operating costs. In addition, the converter in the VSD system
performs a ‘soft’ start/stop operation by automatically controlling both acceleration and deceleration levels. This eliminates the start-up amperage spikes, which can result in hefty peak current cost penalties from utility companies. Eliminating these peaks also protects electrical and mechanical components from the stresses that can shorten the life of an air compressor.
the primary benefitS of VSD
Of the three primary benefits that VSD technology brings to compressor users − energy efficiency, reliability, and connectivity – it is energy efficiency that is the key to affordable air, with up to 50% achievable savings, and lower cost of ownership. Even though the compressor’s initial price tag
is likely to be higher than that of equivalent, fixed- speed models, VSD compressors are actually less expensive to own and operate over their lifetime. That is because they consume far less energy. Increased efficiency also lowers emission levels
and allows for a more sustainable production. Atlas Copco’s VSD compressors can function
even in the toughest conditions. That means being capable of operating at ambient temperatures of up to 46˚C and making certain that the electrical cubicle of the inverter can withstand temperatures of up to 55˚C. It also includes components such as the IP66-rated drive train which is designed to keep out dust and moisture.
new technology
More air, smaller footprint, less energy cost − Atlas Copco’s latest revolutionary compact GA VSD+ compressors bring savings to medium and large-scale operations. The new technology eliminates most challenges associated with the original VSD designs, starting with the performance of the integral, in-house designed Neos compact inverter unit, which contributes to an overall 8% improvement in Specific Energy Requirement (SER) over comparable compressors. The game-changing innovation of the VSD+
design is in the close-coupled drive train − the combination of a high-efficiency motor and technically advanced, asymmetric compression element. The IP55 motor was
designed in-house with special attention to cooling requirements and efficiency. With no coupling or gears between the motor
and screw element, the compressors are quiet 73dB (A) and energy-efficient. The vertical aspect drive train of the VSD+ machines is a closed circuit in which both the motor and the element is cooled with oil, meaning additional energy savings. Added to this is a 6% increase in free air delivery for improved efficiency and performance, plus a reduction in the compressors’ total lifecycle costs in the order of 37%.
Smart communication
Connectivity with advanced monitoring and control systems makes the compressor easier to operate and increases efficiency and reliability. For example, Atlas Copco’s VSD+ compressors come with a high-tech Elektronikon Touch controller and the optional SMARTLINK monitoring system. In combination, these features make it possible to optimise a compressor remotely using a computer or mobile device. That makes compressed air production even more efficient (and greener). In addition, the system anticipates potential issues and alerts the operator before they become problems.
technology of the future
The move toward connectivity and digitalisation in the era of Industry 4.0 is now a reality rather than a distant future. Atlas Copco is a leader in the use of OPC UA communication technology in compressors. OPC UA is the common language that allows equipment to ‘speak’ with each other and ensures that an operation runs smoothly. Because a compressor is too important not
to be part of a networked production operation, Atlas Copco has released its first series of compressors that speak this universal language and has assured compressor users that, in the future, it will be possible to install this technology retroactively. The upsides to being at the forefront of this
technology are obvious: The possibilities that the new connectivity offers will completely change manufacturing as we know it. In the world of compressed air, it is the biggest thing since VSD compressors redefined energy efficiency and changed the industry forever.
Atlas Copco
www.atlascopco.co.uk/compressors
JUNE 2022 DESIGN SOLUTIONS 51
FEATURE
Page 1 |
Page 2 |
Page 3 |
Page 4 |
Page 5 |
Page 6 |
Page 7 |
Page 8 |
Page 9 |
Page 10 |
Page 11 |
Page 12 |
Page 13 |
Page 14 |
Page 15 |
Page 16 |
Page 17 |
Page 18 |
Page 19 |
Page 20 |
Page 21 |
Page 22 |
Page 23 |
Page 24 |
Page 25 |
Page 26 |
Page 27 |
Page 28 |
Page 29 |
Page 30 |
Page 31 |
Page 32 |
Page 33 |
Page 34 |
Page 35 |
Page 36 |
Page 37 |
Page 38 |
Page 39 |
Page 40 |
Page 41 |
Page 42 |
Page 43 |
Page 44 |
Page 45 |
Page 46 |
Page 47 |
Page 48 |
Page 49 |
Page 50 |
Page 51 |
Page 52 |
Page 53 |
Page 54 |
Page 55 |
Page 56 |
Page 57 |
Page 58 |
Page 59 |
Page 60 |
Page 61 |
Page 62 |
Page 63 |
Page 64 |
Page 65 |
Page 66
