Summary: | 碩士 === 國立成功大學 === 電機工程研究所 === 83 === The digitally redesigned pulse-amplitude modulated (PAM)
controller for input time-delay and non-delay systems with
nonsynchronous sampling is first developed to improve
states discrepancies, so that states at original systems with
discrete-time controller will closely match those with
continuous-time controller. Also, the ideal state
reconstructor of the nonsynchronous sampling case is
developed to determine states from the information tion
contained in outputs as well as inputs of dynamic systems
without building an observer. Furthermore, we present a
hybrid suboptimal control of multi-rate multi-loop
sampled data systems with the nonsynchronous sampling at
outputs ports of both loops. First, we utilize an optimal
regional-pole placement technique to find an optimal
state-feedback control law for a subsystem connected in
the inner loop of the overall system. Next, the redesigned
analogue control law is converted into equivalent fast-
rate digital control law using the recently developed
digital redesign method. Then we modify the digital control
law to eleminate the nonsynchronous sampling effect in the
inner loop port. Furthermore, we convert the modified
digital control system into an equivalent continuous-time
model. As a result, the overall continuous-time model
can be formulated from the convertered analogue subsystem
and the rest of analogue subsystems to be designed. Moreover,
following the preceeding step, we find an optimal control law
for an overall system and convert it into an equivalent
slow-rate digital control law to eleminate the nonsynchronous
sampling effect in the outter-loop port and complete the
design.
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