Add impedance control mode
This mode regulates the input current such that the load to the generator has a constant, defined impedance. The impedance is set such that it matches the ratio between the specified motor voltage and current. In that case, the power extracted from the motor/generator ist maximized.
This commit is contained in:
Thomas Kolb
parent
8746b51bd5
commit
55e6d5d9db
|
|
@ -300,8 +300,9 @@ fn main() -> ! {
|
|||
|
||||
// Green LED is on in constant-voltage mode and off in MPPT mode.
|
||||
match switchctrl.get_control_mode() {
|
||||
switch_control::ControlMode::ConstantVoltage => {pin_led_g.set_high().unwrap()},
|
||||
switch_control::ControlMode::MPPT => {pin_led_g.set_low().unwrap()},
|
||||
switch_control::ControlMode::ConstantVoltage => {pin_led_g.set_high().unwrap()},
|
||||
switch_control::ControlMode::MPPT => {pin_led_g.set_low().unwrap()},
|
||||
switch_control::ControlMode::ImpedanceControl => {pin_led_g.set_low().unwrap()},
|
||||
}
|
||||
|
||||
// do not output status data every loop
|
||||
|
|
|
|||
|
|
@ -6,7 +6,8 @@ const PWR_AVG_EXPONENT: i64 = 12;
|
|||
#[derive(Copy, Clone)]
|
||||
pub enum ControlMode {
|
||||
MPPT,
|
||||
ConstantVoltage
|
||||
ConstantVoltage,
|
||||
ImpedanceControl
|
||||
}
|
||||
|
||||
struct PID<const GAINSCALE: i32, const T0: i32>
|
||||
|
|
@ -217,12 +218,68 @@ impl<const INTERVAL: u32, const PERCENT_LOSS_TOLERANCE: i32> MPPT<INTERVAL, PERC
|
|||
}
|
||||
}
|
||||
|
||||
struct ImpedanceControl<const T0: i32, const MOTOR_SPEC_U: i32, const MOTOR_SPEC_I: i32>
|
||||
{
|
||||
pid: PID::<10000, T0>,
|
||||
iin_target: i32,
|
||||
}
|
||||
|
||||
impl<const T0: i32, const MOTOR_SPEC_U: i32, const MOTOR_SPEC_I: i32> ImpedanceControl<T0, MOTOR_SPEC_U, MOTOR_SPEC_I>
|
||||
{
|
||||
pub fn new(i_target_initial: i32, max_pwm: i32) -> Self
|
||||
{
|
||||
ImpedanceControl::<T0, MOTOR_SPEC_U, MOTOR_SPEC_I> {
|
||||
pid: PID::<10000, T0>::new(10, 5, 2, i_target_initial, 0, 0, max_pwm * 10000),
|
||||
iin_target: i_target_initial
|
||||
}
|
||||
}
|
||||
|
||||
pub fn restart(&mut self, start_pwm: i32)
|
||||
{
|
||||
self.pid.restart_from_output_value(start_pwm);
|
||||
}
|
||||
|
||||
pub fn update(&mut self, vin: i32, vout: i32, iout: i32) -> i32
|
||||
{
|
||||
let pout = vout * iout;
|
||||
let iin;
|
||||
|
||||
if vin <= 0 {
|
||||
iin = 0;
|
||||
} else {
|
||||
iin = (pout / vin) * 85 / 100;
|
||||
}
|
||||
|
||||
self.iin_target = vin * MOTOR_SPEC_I / MOTOR_SPEC_U;
|
||||
|
||||
self.pid.set_target(self.iin_target);
|
||||
|
||||
self.pid.update(iin)
|
||||
}
|
||||
|
||||
pub fn log_status(&self, logger: &mut dyn Logger)
|
||||
{
|
||||
let mut data: String<16>;
|
||||
|
||||
logger.log(b"I_target: ").unwrap();
|
||||
|
||||
data = String::from(self.iin_target);
|
||||
logger.log(data.as_bytes()).unwrap();
|
||||
|
||||
logger.log(b"mA - ").unwrap();
|
||||
|
||||
self.pid.log_status(logger);
|
||||
}
|
||||
}
|
||||
|
||||
|
||||
pub struct SwitchControl<const T0: i32>
|
||||
{
|
||||
mode: ControlMode,
|
||||
mode_switch_delay_counter: u32,
|
||||
cv_pid: PID<10000, T0>,
|
||||
mppt: MPPT<200, 0 /* percent loss of peak power */>,
|
||||
imp_ctrl: ImpedanceControl<T0, 11000, 15000>,
|
||||
pwm_max: i32,
|
||||
pwm_cur: i32,
|
||||
cv_target: i32,
|
||||
|
|
@ -234,10 +291,11 @@ impl<const T0: i32> SwitchControl<T0>
|
|||
pub fn new(cv_target: i32, cv_max_deviation: i32, pwm_max: i32) -> Self
|
||||
{
|
||||
SwitchControl::<T0> {
|
||||
mode: ControlMode::MPPT,
|
||||
mode: ControlMode::ImpedanceControl,
|
||||
mode_switch_delay_counter: 0,
|
||||
cv_pid: PID::<10000, T0>::new(100, 50, 50, cv_target, 0, 0, pwm_max * 10000),
|
||||
mppt: MPPT::<200, 0>::new(3*pwm_max/4, 0, pwm_max),
|
||||
imp_ctrl: ImpedanceControl::<T0, 11000, 15000>::new(1000, pwm_max),
|
||||
pwm_max,
|
||||
pwm_cur: 0,
|
||||
cv_target,
|
||||
|
|
@ -246,7 +304,7 @@ impl<const T0: i32> SwitchControl<T0>
|
|||
}
|
||||
|
||||
// returns the new PWM value
|
||||
pub fn update(&mut self, _vin: i32, vout: i32, iout: i32) -> i32
|
||||
pub fn update(&mut self, vin: i32, vout: i32, iout: i32) -> i32
|
||||
{
|
||||
// Mode switching (only if delay counter has expired)
|
||||
if self.mode_switch_delay_counter == 0 {
|
||||
|
|
@ -260,14 +318,26 @@ impl<const T0: i32> SwitchControl<T0>
|
|||
self.mode_switch_delay_counter = 100;
|
||||
},
|
||||
|
||||
ControlMode::ImpedanceControl =>
|
||||
if vout > self.cv_target {
|
||||
self.mode = ControlMode::ConstantVoltage;
|
||||
self.cv_pid.restart_from_output_value(self.pwm_cur * 80 / 100);
|
||||
|
||||
// stay in CV mode for at least 100 update cycles
|
||||
self.mode_switch_delay_counter = 100;
|
||||
},
|
||||
|
||||
ControlMode::ConstantVoltage =>
|
||||
if vout < self.cv_target - self.cv_max_deviation {
|
||||
self.mode = ControlMode::MPPT;
|
||||
self.mode = ControlMode::ImpedanceControl;
|
||||
|
||||
// begin MPPT tracking by searching downwards, because the CV PID controller
|
||||
// probably has pushed the PWM to the upper limit due to too low output
|
||||
// voltage.
|
||||
self.mppt.restart(self.pwm_max * 80 / 100, -1);
|
||||
//self.mppt.restart(self.pwm_max * 80 / 100, -1);
|
||||
|
||||
// back to impedance control
|
||||
self.imp_ctrl.restart(self.pwm_max * 80 / 100);
|
||||
}
|
||||
}
|
||||
} else {
|
||||
|
|
@ -278,6 +348,7 @@ impl<const T0: i32> SwitchControl<T0>
|
|||
let pwm = match self.mode {
|
||||
ControlMode::ConstantVoltage => self.cv_pid.update(vout),
|
||||
ControlMode::MPPT => self.mppt.update(vout, iout),
|
||||
ControlMode::ImpedanceControl => self.imp_ctrl.update(vin, vout, iout),
|
||||
};
|
||||
|
||||
// store and limit pwm value
|
||||
|
|
@ -303,6 +374,11 @@ impl<const T0: i32> SwitchControl<T0>
|
|||
logger.log(b"[CV] ").unwrap();
|
||||
self.cv_pid.log_status(logger);
|
||||
}
|
||||
|
||||
ControlMode::ImpedanceControl => {
|
||||
logger.log(b"[Imp] ").unwrap();
|
||||
self.imp_ctrl.log_status(logger);
|
||||
}
|
||||
}
|
||||
|
||||
logger.log(b"\r\n").unwrap();
|
||||
|
|
|
|||
Loading…
Reference in New Issue