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MazdaMatt · 05-20-2009, 03:22 PM

JayC, the purpose for the PI controller is the preference to control current, rather than duty cycle. Current is a function of duty cycle and RPM, so at 0RPM a 1%duty has a HUGE current draw. At 1000RPM a 1% duty has a small current draw. Since current is directly proportional to torque, we felt that we should be relating the pedal position to current so that the control is a) more intuitive and b) you don't burn out at every stoplight.

05-20-2009, 03:22 PM	#1326 (permalink)
MazdaMatt Master EcoModder Join Date: Jun 2008 Location: London, Ontario Posts: 1,096 2k2Prot5 - '02 Mazda Protege5 90 day: 33.82 mpg (US) Thanks: 0 Thanked 17 Times in 14 Posts	JayC, the purpose for the PI controller is the preference to control current, rather than duty cycle. Current is a function of duty cycle and RPM, so at 0RPM a 1%duty has a HUGE current draw. At 1000RPM a 1% duty has a small current draw. Since current is directly proportional to torque, we felt that we should be relating the pedal position to current so that the control is a) more intuitive and b) you don't burn out at every stoplight.