In reality, the resolver sensor is basically a rotary transformer
. Because its reliability comes from its simplicity, it can withstand the same environmental hazards as the motor it tracks.
The electrical connection is made to the stationary coil, but a rotary transformer
is required for temperature sensing.
An induction coil in the rotor and an adjacent coil in the stator work together as a radio frequency rotary transformer
. This transformer has two functions.
A resolver is a rotary transformer
that puts out a variable voltage signal and is typically more expensive than an encoder.
The power is sent to the balancer by means of a rotary transformer
developed and patented by BalaDyne.
On the basis of methods for power and signal transfer between stationary and rotating environments in torque measurement; rotary torque sensors have been further segmented into slip-rings, rotary transformers
, rotary electronics, FM telemetry and so on.
For decades, slip ring and rotary transformers
have been used to measure torque.