Emerson 540VDC manual Flywheel Sensors Speed, Temperature

System Overview

5.1.12Flywheel Sensors Speed

The speed detection system uses an infrared emitter and a sensor to detect the rotation of the shaft. A hole drilled through the shaft allows light to pass and is detected on the opposite side by an infrared detector. This signal is used to detect the rotor angle, the speed and any over speed condition. The pulsed signal passes into the 6711 DSP to be converted into a speed signal. This is then passed to the 2812 DSP. The 2812 checks for over-speed and shuts down the power electronics if this occurs. If either of the processors lock-up, the rotor will slow down, this guarantees that on over-speed cannot occur.

Temperature

The stator and rotor temperature detectors are thermocouples and are both conditioned in a similar way. The stator sensor is a Type J thermocouple potted into the stator windings. The rotor sensor is a non-contact type sensor that detects the temperature of the rotor surface and gives an output in a Type J thermocouple format.

Figure 42 Schematic for the speed and temperature sensors

NON- CONTACT

ROTOR

TEMPERATURE

SENSOR

JTYPE

THERMOCOUPLE

OUTPUT

STATOR	ROTOR
WINDINGS

STATOR	AMPLIFIERS, CONDITIONERS,
TEMPERATURE
SENSOR	LINEARIZERS AND COLD
J TYPE	JUNCTION COMPENSATION IN
THERMOCOUPLE	ONE CHIP

SUPPLY

FROM

CIRCUIT BOARD

INFRARED

DETECTOR

CONDITIONER

AND DIVIDE BY 2

DSP 6711

TIMER INPUT DETERMINES SPEED

DSP 2812

DETECTS OVERSPEED

41	DISCONTINUED
	PRODUCT