The Complete Package
Innovative VSD - Motor Matching Doubles Motor Life*
The perfect match between an electric motor and VSD has finally been taken to the next level. WEG's massive R&D investment and the joint expertise of electric motor and VSD design engineers have addressed two of the major drawbacks of modern PWM drives: increase in motor temperature rise and fast transient high voltage peaks, the consequence of both being a dramatic reduction in motor life.
The new CFW11 WEG drives minimise voltage surges by carefully regulating the time between pulses of their IGBT transistors. This decreases the possible surge magnitude by 50%, allowing longer cable runs without the detrimental effects to motor insulation.
Flux-optimising technology (patented) decreases motor temperature rise by as much as 11%. *Since insulation life is doubled by every 10 degrees Celsius decrease in its operating temperature, this new WEG technology can increase motor life by as much as two-fold. A combination of low VPEAKS and dV/dt at the motor terminals, lower motor temperature rise, and high performance Drive and Motor architecture makes WEG the perfect solution to the most arduous industrial applications.
This new technology redefines the concept of a matched motor and drive package, with concrete benefits to users over and above the usual concept of matched packages.
Eight good reasons why you should consider a WEG motor and variable speed drive package
Redefining motor & drive packages
What is a matched Package?
Generally, when industry refers to a motordrive package they mean a motor and drive from the same supplier. This does not necessarily mean that the motor and drive are manufactured by the same supplier, nor does it provide any additional technical benefit. In fact if there is a problem, responsibility of rectification may be shifted from one supplier to another.
Technical benefits of WEG Motor & Drive Packages
•A motor and drive, engineered and manufactured by the same supplier. You the end user are buying peace of mind.
•Technically integrated solutions with motors and drives, which can add measurable technical benefits and tangible cost advantages to you the end user.
•Option of motor and drive packages being tested together under full load conditions prior to dispatch from the factory.
•Drives designed to limit dV/dt and Vpeak in accordance with motor insulation system.
•Drives are designed with the motor electromagnetic model built in to its vector control software, so as to minimise motor temperature rise, hence extending motor life.
2. Inverter-rated insulation
WEG’s R & D department have been studying the effects of PWM drives on AC electric motors for years, which has resulted in WEG incorporating the most advanced technology into their products.
When a motor is connected to a VSD the motor insulation is subjected to high levels of dV/dt. Voltage spikes of approximately 1,500V, and transient of 5,000V/ìs, occurring at a rate of 4,000 per second are common occurrences. This exerts extremely high stress on a motor’s insulation system.
There are today only a few suppliers of special wire for inverter fed motors, which the industry has anointed as ‘Spike Resistant-Wire’.
Due to their high cost, most manufacturers are still using standard GRADE 2 or 3 wire. Accelerated life tests have shown that the life of a standard insulation system may be reduced by as much as 75% when subjected to the high dV/dt levels and voltage spikes generated by modern inverters. All WEG motors are wound with spike-resistant wire rated 1500VPEAK and 5,200V/ìs.
No forced cooling required
Vector control technology permits the operation of standard induction motors at very low speeds for extended periods of time. However, operation below rated speed affects the cooling efficiency of the shaft-driven fan, which results in increased motor temperature rise. To overcome that limitation, engineers developed derating factors and forced cooling fan systems. A practical rule dictated either of the two had to be applied for operation at or below 40Hz.
With WEG’s new Optimal Flux Technology (patented) this requirement is now a thing of the past. Each CFW09 and CFW11 (VECTRUE Inverter) has the electromagnetic circuit model of the WEG MEPS compliant motor built in. By carefully optimising the V/F ratios whilst the inverter is operating, the current (and therefore the motor heating) can be precisely controlled. The end result is a motor and drive package which must be regarded as a truly integrated solution to a long standing and expensive problem.
When a CFW09 and CFW11 inverter is used in conjunction with the WEG MEPS compliant range of motors and the continuous operating speed is 10Hz or above there is NO requirement for external forced cooling. This represents an ‘Up Front’ cost saving to the end user. Since there is no cooling fan, this also means there is also no power or control infrastructure. Furthermore, the absence of a fan motor yields ongoing energy savings with respect to fan energy usage. This alone may represent a saving of hundreds of dollars per year.
This system is only valid for with the WEG MEPS compliant Motors and CFW09 and CFW11 Variable speed Drives.
4. Optimal breaking
Traditional DC injection braking provides limited breaking torque, hence extending deceleration time with a corresponding increase in process cycle times. This can be costly for production lines, where short cycle times increase productivity and consequently, the organisation’s revenue. WEG’s optimal breaking (patented) is capable of reducing breaking time by up to 30%, especially in smaller motors.
The Vector control technique allows separate control of the Motor Torque and Flux Currents. Optimal Braking is composed of two control blocks :
•DC bus regulator: The torque current is used to control the DC bus voltage level. By controlling the amount of energy regenerated to the drive it avoids an overvoltage trip during deceleration.
•Increased motor losses: The flux current is used to increase motor electric losses and still maintain magnetic flux at a constant value. This occurs during deceleration only, hence with no impact on energy costs.
Optimal Braking dissipates the braking energy in the same motor which generates it, thereby eliminating the external braking resistor (in some applications) and also the IGBT on the DC bus.
The result is: More Braking Torque Availability !!! Reduced Initial Outlay
Optimal Braking is used where there is a requirement for increased braking over the standard applications. In fact the Optimal braking system can provide 100% braking from 25Hz down.
Optimal Braking is not designed to be used in highly regenerative applications, ie; hoisting, slipways and incline conveyors.
5. Oriented start-up
The CFW09 & CFW11 incorporate a feature called ‘Oriented Start-up’.
This feature steps the use through the set-up procedure. Upon first power up or after a reset to factory default parameters, an automatic programming routine guides the operator through a sequence of steps designed for the accurate completion of the minimum number of parameters necessary for the perfect match between motor and drive.
P400 = Motor Volts
P401 = Motor Current
P402 = Motor RPM
P403 = Motor Frequency
P404 = Motor kW
P406 = Ventilation Type
P408 = Auto Tuning Routine
For a fast, accurate motor/drive setup procedure.
Once the ‘Oriented Start-up’ and commissioning procedure has been completed the entire programme may then be stored in ‘Non– Volatile
Memory’ in the drive keypad. This allows the programme to be up/down loaded at any time, even to another drive of the same capacity. Two ‘User Files’ can be stored within the drives and can be ‘called up’ with a digital input at any time.
The Auto Tuning procedure is specific to the motor/drive combination and should be carried out whenever this combination is changed.
WEG Drives and Soft Starters share common parameters and programming, which can be modified and stored via keypad or PC.
6. Service and back-up
Having a world class product is one thing. Service, training and backup is quite another. WEG have implemented the following strategies to assist you, the user, in having total peace of mind.
1.WEG operates through its local agents and provides training to all these agencies at regular intervals. These local agents are backed by factory trained specialists.
2.WEG provides training at the users premises (Free Of Charge) or at our training facilities located in Matamata, Christchurch, and Auckland.
3.Under certain circumstances a local agent may assist the customer by carrying stocks of key equipment.
4.A full range of spare parts are held by WEG. Because of the high levels of accessibility of the CFW09 and CFW11, most repairs, if needed, can be carried out on site.
5.WEG has been manufacturing Drives & Soft Starters for over 24 years for the world market. With over 1,500 engineers in the engineering, R&D and service departments, and high level of integration between our electric motor and drive divisions. WEG provide world-class technologically advanced drives, with unique and innovative features (optimal flux and optimal breaking) which are designed to be motor-friendly, providing the best performance improving motor life and reducing the total cost of ownership.
7. Quality control
WEG is an ISO9001 and ISO14000 certified company (by BVQI in England). WEG’s strict QA procedures mandate functional testing of 100% of control cards.In addition, all drives are load tested for 2 hours. These tests are a pass or failure test, and and are carried out on all WEG drives at no additional cost. Other tests, including witness tests, can be performed upon request.
8. WEG motor and drive package
All WEG standard ‘Off the Shelf’ motor products are designed to withstand 1,500VPEAK and 5,200V/ìs @ 5kHz. This covers up to 95% of applications with PWM drives today.
Based on the aforementioned spike-resistant wire ratings, dV/dt filters are not required if the following drive operating conditions are met.
1 Maximum VPEAK at the motor terminals: VPEAK = 1,500V
2 VSD rise time tr >= 0.1ìs
3 Time between consecutive pulses >= 6ìs
All WEG CFW09 and CFW11 Drives are been engineered to meet the above operating conditions at the inverter terminals. Likewise all WEG motors have been designed to withstand high levels of dV/dt and VPEAK.
The end result is a motor and drive solution which has been truly engineered to withstand the most difficult of operating conditions.
Additional to the individual benefits of WEG motors and WEG drives, when used together the following advantages are enjoyed:
•WEG optimal flux (patented) technology ensures motor efficiency is optimised. The benefit for you the user is energy savings and longer motor life
•Longer cable lengths without the need for output reactors