The FR-E800 supports the following control Methods
Various control methods are supported to expand applications
One of the many advantages of the FR-E800 inverter family lies precisely in having, despite its compactness, technical features and management complexity that are very close to those of the top-class family.
The table below is intended to provide an overview of all the control methods that the E800 family can perform (speed, positioning, torque) depending also on the motor being driven (induction or permanent magnets).
Scalar Control: V/F
It is based on a scalar proportion between frequency and voltage. Being an open-loop control system, the inverter does not receive feedback from the field. It is used mainly in applications where I do not need “complex” positioning or dynamics and for general purposes (pumps, fans, compressors and spindles for example).
Open-Loop Vector Control: Advanced Magnetic Flux / Real Sensorless Vector Control (RSVC)
The output current is split into excitation current and torque current so that the inverter can modulate its magnitude as needed. It is also useful for saving current consumption and optimizing its use on the motor side. Effective in heavy-duty applications (e.g., cranes).
High torque performance can be achieved at low speeds:
- Advanced → 150% of rated torque at 1 Hz
- RSVC →200% of rated torque at 0.3 Hz
Closed-Loop Vector Control (FR-A8AP E Kit + Encoder)
This closed-loop vector control requires the presence of an electrical transducer (encoder/resolver) to provide feedback (position, speed, or torque) from the motor. In this way, without estimating or prefixing characteristic values, the inverter is able to control the motor by following its actual behaviour.
Application Examples
Vector control (closed-loop vector control) enables accurate movement and positioning of PET bottles, for example, in filling operations. (This mode requires the presence of an optional FR-A8APE kit board for use with an encoder.)
With the PM sensorless vector control mode, I can control the position and speed of a permanent magnet motor (e.g., a palletizing line) without using an encoder. Through autotuning to be carried out in the offline mode of the motor, the inverter estimates its behaviour and implements the necessary actions (frequency, current and output voltage) for high-speed control and positioning of the pallets.
- From simpler control methods like scalar V/F up to more advanced open or closed-loop controls, therefore with or without encoder
- High performance at a lower cost
- Versatility and transversality for different industrial applications