Freescale Semiconductor, Inc.
Hardware Design
3-Phase AC BLDC High Voltage Power Stage
3.4 3-Phase AC BLDC High Voltage Power Stage
Motorola’s embedded motion control series high-voltage (HV) AC power
stage is a 180-watt (one-fourth horsepower), 3-phase power stage that
will operate off of DC input voltages from 140 to 230 volts and AC line
voltages from 100 to 240 volts. In combination with one of the embedded
motion control series control boards and an optoisolation board, it
provides a software development platform that allows algorithms to be
written and tested without the need to design and build a power stage. It
supports a wide variety of algorithms for both AC induction and
brushless DC (BLDC) motors.
Input connections are made via 40-pin ribbon cable connector J14.
Power connections to the motor are made on output connector J13.
Phase A, phase B, and phase C are labeled Ph_A, Ph_B, and Ph_C on
the board. Power requirements are met with a single external 140- to
230-volt DC power supply or an AC line voltage. Either input is supplied
through connector J11. Current measuring circuitry is set up for 2.93
amps full scale. Both bus and phase leg currents are measured. A
cycle-by-cycle over-current trip point is set at 2.69 amps.
The high-voltage AC power stage has both a printed circuit board and a
power substrate. The printed circuit board contains IGBT gate drive
circuits, analog signal conditioning, low-voltage power supplies, power
factor control circuitry, and some of the large, passive, power
components. All of the power electronics, which need to dissipate heat,
are mounted on the power substrate. This substrate includes the power
IGBTs, brake resistors, current sensing resistors, a power factor
correction MOSFET, and temperature sensing diodes. Figure 3-3
shows a block diagram.
DRM019 — Rev 0
MOTOROLA
Designer Reference Manual
Hardware Design
31
For More Information On This Product,
Go to: www.freescale.com
ETC [ ETC ]
