The actuator has an electrical side
and a mechanical side. The most
important principle is that current in
an electrical conductor move inside
of a magnetical field. Such actuators
has the ability to convert electrical
energy to mechanical energy and vice
versa. The energy conversion takes
place in and around the rotor. It is
easy to explain the conversion with the Lorentz-force law.
The actuator is working in motor mode when electrical power is transformed to mechanical power. It
is in generator mode as mechanical power is transformed to electrical power. When an actuator gets
both electrical and mechanical energy input it is a dissipator (plugging mode). This mode can be used
as a brake. Figure shows schematically the electrical mechanical converter with the possible
energy flows.
A magnetic field is necessarily for the conversion, which gives always losses of electrical, mechanical
and magnetical nature. The mechanical losses are ventilation, the static and viscous friction; electrical
losses are conduction (copper) losses. The magnetical losses can be iron losses (eddy current) or
indirect from leakage fields. In chapter 2 the magnetical losses will be described. All the losses caused
an irritating heat, which reduces the functions of the actuator.
No comments:
Post a Comment