Analog Processor Board; Figure 1-3 Analog Processor Board Block Diagram - Cal Power TrueWave TW5250 Service Manual

THEORY OF OPERATION TW SERIES
1.5

ANALOG PROCESSOR BOARD

Digital
Control
Board
QSPI
POWER
SUPPLY
WAVEFORM
TMS320C50 SERVO POWER
DACs
PROCESSOR AMPLIFIERS AMPLIFIERS
8 CHANNEL VOLTAGE
ADC DAC
FIGURE 1-3. ANALOG PROCESSOR BOARD BLOCK DIAGRAM
The Analog Processor Board generates the three–phase sinewave references, signal
processes the sampled currents and voltages, performs output voltage servoing, and
drives the power amplifiers. Additionally the Analog Processor Board has a power
supply that provides fan power and front panel power.
Processing power is provided by a TMS320C50 digital signal processor (DSP). The
DSP's firmware is loaded into the processor at power up from the Digital Control Board.
After initializing all registers and calibrating the analog to digital converter, the DSP
enters its main control loop. All waveform generation and measurements are handled
by the DSP. Current mode of operation is also controlled by the DSP. Hardware faults
are monitored by the DSP and appropriate actions are taken by the DSP when a fault
occurs.
The sinewave references are constructed using three waveform DACs and one
amplitude DAC driving the voltage reference. The DSP updates each of the waveform
DACs every 37.5 microseconds with the appropriate amplitude value for the phase
waveform being constructed. The output of the DACs are filtered by a 5 pole waveform
construction filter to eliminate any steps in the waveform. The amplitude DAC is
updated as necessary to set the maximum peak to peak output voltage generated by
the TW.
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