Asynchronous motor for frequency converter fed operation
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VEM TECHNIK we get things moving As ynchronous motor for frequency inverter fed operation we get things moving

Inverter fed asynchronous motors are used, on an increasing scale, in all industrial applications, when a low-loss speed control of driven machines is important, and therefore, an optimum adaptation of the motor speed to the technological procedure must be implemented. VEM three-phase motors with squirrel-cage rotor are available in two versions, both of them based on the dimensions and sizes of IEC 60072 (type correlation see tables Motor Selection Data in the current VEM catalogue). The K21R / K22R motors are classic IEC/DIN coordinated series, i.e. the coordination of mounting dimensions...

Motors of series KV.R for inverter output voltages up to ≤ 690 V Û ≤ 2,5 kV For motors of the series KV.R, high-performance insulation materials are used, that will ensure the inverter fed operation up to 690 V without any filtering techniques. This insulation system is designed for pulse voltages up to 2,5 kV at the motor terminals. The insulation system is based on copper wires LFg (30), varnish insulated Grade 1, taped with mica foil tapes. Due to the larger space of the insulation material, the electrically active slot space is reduced, therefore, the motors of design versions KV1R,...

Planning advices for motors for frequency converter operation Motors are only one part of an complex electrical drive system. In case of a faulty design of a drive system, mainly the motor is blamed, whereas taking an incorrect planning of the drive transmission elements into account, the couplings and belt pulleys will suffer too. Today’s inverters protect themselves and the motor against thermal overload. But they do not detect excessive voltage spikes at the motor terminals. For the drive system, problems could arise from missing filter technologies at the inverter output, and /or from...

Motor limits for continuous operation The planning of variable speed drives prerequisites both the knowledge about the torque or the output along the speed of the driven machine, and also for the motor itself. Within the speed range below the nominal motor speed, the torque for the continuous operation (limit torque) must be observed, and for speed above the nominal motor speed, the reduced break-down torque must be taken into account. The provided torque depends both on the motor (design, cooling method, etc.) and the inverter (parameters, pulse frequency, modulation procedure, output...

Ohmic stator resistance for smaller motors For lower motor outputs, the relatively high Ohmic stator resistance must be taken into account increasingly. For the lower frequency range, it is required to compensate this phenomena by a disproportionaly high increase of the inverter output voltage (IxR compensation). By this measure, a safe acceleration of the motor under load up to the requested speed is enabled. Break-down torque For motor operation in the field weakening range, (with constant voltage along the motor design frequency) the break-down torque decreases squarely with increasing...

Motor selection data Motors with squirrel-cage rotor, inverter feeding without inverter wiring (dU/dt-filter, sine filter), U < 690 V ( U > 1,8 kV < 2,5 kV) with surface ventilation, mode of operation S1, continuous duty insulation class F, degree of protection IP 55 Synchronous speed 3000 miri - 2-pole The given currents concern inverter output voltage of 690 V Vorlaufige technische Daten.

Motor selection data Motors with squirrel-cage rotor, inverter feeding without inverter wiring (dU/dt-filter, sine filter), U < 690 V ( U > 1,8 kV < 2,5 kV) with surface ventilation, mode of operation S1, continuous duty insulation class F, degree of protection IP 55 Synchronous speed 1000 miri - 6-pole Provisional technical data.