variable tesla refresh period + low voltage timeout + better valid rate checking

Cargo.lock

@@ -2256,7 +2256,7 @@ dependencies = [
 
 [[package]]
 name = "tesla-charge-controller"
-version = "1.0.0-beta-2"
+version = "1.0.0-beta-3"
 dependencies = [
  "async-channel",
  "chrono",

Cargo.toml

@@ -1,6 +1,6 @@
 [package]
 name = "tesla-charge-controller"
-version = "1.0.0-beta-2"
+version = "1.0.0-beta-3"
 edition = "2021"
 license = "MITNFA"
 description = "Controls Tesla charge rate based on solar charge data"

src/config.rs

@@ -16,12 +16,14 @@ pub fn access_config<'a>() -> &'a Config {
 #[derive(Serialize, Deserialize, Clone, Debug)]
 pub struct Config {
     pub tesla_update_interval_seconds: u64,
+    pub tesla_update_interval_while_charging_seconds: u64,
     pub pl_watch_interval_seconds: u64,
     pub pl_timeout_milliseconds: u64,
     pub coords: Coords,
     pub serial_port: String,
     pub baud_rate: u32,
     pub shutoff_voltage: f64,
+    pub shutoff_voltage_time_seconds: u64,
     pub min_rate: i64,
     pub max_rate: i64,
     pub duty_cycle_too_high: f64,
@@ -32,6 +34,7 @@ impl Default for Config {
     fn default() -> Self {
         Self {
             tesla_update_interval_seconds: 120,
+            tesla_update_interval_while_charging_seconds: 5,
             pl_watch_interval_seconds: 30,
             pl_timeout_milliseconds: 250,
             coords: Coords {
@@ -41,6 +44,7 @@ impl Default for Config {
             serial_port: String::from("/dev/ttyUSB0"),
             baud_rate: 9600,
             shutoff_voltage: 52.,
+            shutoff_voltage_time_seconds: 15,
             min_rate: 5,
             max_rate: 10,
             duty_cycle_too_high: 0.9,

src/main.rs

@@ -127,15 +127,26 @@ async fn main() {
                     let mut interval = tokio::time::interval(std::time::Duration::from_secs(
                         config.tesla_update_interval_seconds,
                     ));
+                    let mut charge_interval =
+                        tokio::time::interval(std::time::Duration::from_secs(
+                            config.tesla_update_interval_while_charging_seconds,
+                        ));
                     loop {
                         // await either the next interval OR a message from the other thread
                         tokio::select! {
                             _ = interval.tick() => {
-                                if let Some(request) = tesla_charge_rate_controller.control_charge_rate() {
-                                    interface.process_request(request).await;
+                                if !interface.state.read().unwrap().is_charging_at_home() {
+                                    interface.refresh().await
                                 }
-                                interface.refresh().await
                             },
+                            _ = charge_interval.tick() => {
+                                if interface.state.read().unwrap().is_charging_at_home() {
+                                    if let Some(request) = tesla_charge_rate_controller.control_charge_rate() {
+                                        interface.process_request(request).await;
+                                    }
+                                    interface.refresh().await
+                                }
+                            }
                             api_message = api_receiver.recv() => match api_message {
                                 Ok(message) => interface.process_request(message).await,
                                 Err(e) => panic!("Error on Tesla receive channel: {e:?}")

src/tesla_charge_rate.rs

@@ -1,4 +1,7 @@
-use std::sync::{Arc, RwLock};
+use std::{
+    sync::{Arc, RwLock},
+    time::{Duration, Instant},
+};
 
 use metrics::{describe_gauge, gauge, Gauge};
 use serde::{Deserialize, Serialize};
@@ -15,6 +18,7 @@ pub struct TeslaChargeRateController {
     pub car_state: Arc<RwLock<CarState>>,
     pub pl_state: Option<Arc<RwLock<PlState>>>,
     pub tcrc_state: Arc<RwLock<TcrcState>>,
+    voltage_low: Option<Instant>,
     control_enable_gauge: Gauge,
 }
 
@@ -26,12 +30,14 @@ pub enum TcrcRequest {
 #[derive(Clone, Copy, Serialize, Deserialize, Debug)]
 pub struct TcrcState {
     pub control_enable: bool,
+    pub currently_controlling: bool,
 }
 
 impl Default for TcrcState {
     fn default() -> Self {
         Self {
             control_enable: true,
+            currently_controlling: false,
         }
     }
 }
@@ -43,6 +49,7 @@ impl TeslaChargeRateController {
             car_state,
             pl_state,
             tcrc_state: Default::default(),
+            voltage_low: None,
             control_enable_gauge: gauge!("tcrc_control_enable"),
         }
     }
@@ -52,14 +59,26 @@ impl TeslaChargeRateController {
             if let Ok(car_state) = self.car_state.read() {
                 if let Some(charge_state) = car_state.charge_state {
                     // check if we're charging at home
-                    if charge_state.charging_state == ChargingState::Charging
-                        && car_state.location_data.is_some_and(|v| v.home)
-                    {
+                    if car_state.is_charging_at_home() {
                         // automatic control or not, check if we're below shutoff voltage
                         if pl_state.battery_voltage < access_config().shutoff_voltage {
-                            return Some(InterfaceRequest::StopCharge);
-                        } else if self.tcrc_state.read().is_ok_and(|v| v.control_enable) {
-                            return get_control(&pl_state, &charge_state);
+                            if let Some(low_voltage_time) = self.voltage_low {
+                                // if we've been below shutoff for long enough, stop charging
+                                if Instant::now().duration_since(low_voltage_time)
+                                    >= Duration::from_secs(
+                                        access_config().shutoff_voltage_time_seconds,
+                                    )
+                                {
+                                    return Some(InterfaceRequest::StopCharge);
+                                }
+                            } else {
+                                self.voltage_low = Some(Instant::now());
+                            }
+                        } else {
+                            self.voltage_low = None;
+                            if self.tcrc_state.read().is_ok_and(|v| v.control_enable) {
+                                return get_control(&pl_state, &charge_state);
+                            }
                         }
                     } else if charge_state.charging_state == ChargingState::Disconnected {
                         // only disable automatic control until the next time we're unplugged
@@ -98,20 +117,22 @@ impl TeslaChargeRateController {
 fn get_control(pl_state: &PlState, charge_state: &ChargeState) -> Option<InterfaceRequest> {
     let config = access_config();
     if pl_state.duty_cycle > config.duty_cycle_too_high {
-        let new_rate = charge_state.charge_amps - 1;
-        return if new_rate >= config.min_rate {
-            Some(InterfaceRequest::SetChargeRate(new_rate))
-        } else {
-            None
-        };
+        let rate = charge_state.charge_amps - 2;
+        return valid_rate(rate, charge_state.charge_amps).map(InterfaceRequest::SetChargeRate);
     } else if pl_state.duty_cycle < config.duty_cycle_too_low {
-        let new_rate = charge_state.charge_amps + 1;
-        return if new_rate <= config.max_rate {
-            Some(InterfaceRequest::SetChargeRate(new_rate))
-        } else {
-            None
-        };
+        let rate = charge_state.charge_amps + 1;
+        return valid_rate(rate, charge_state.charge_amps).map(InterfaceRequest::SetChargeRate);
     }
 
     None
 }
+
+fn valid_rate(rate: i64, other: i64) -> Option<i64> {
+    let config = access_config();
+    let new = rate.min(config.max_rate).max(config.min_rate);
+    if new == other {
+        None
+    } else {
+        Some(new)
+    }
+}

src/types.rs

@@ -11,6 +11,14 @@ pub struct CarState {
     pub climate_state: Option<ClimateState>,
 }
 
+impl CarState {
+    pub fn is_charging_at_home(&self) -> bool {
+        self.charge_state
+            .is_some_and(|v| v.charging_state == ChargingState::Charging)
+            && self.location_data.is_some_and(|v| v.home)
+    }
+}
+
 #[derive(Clone, Copy, Serialize, Deserialize, Debug)]
 pub struct ClimateState {
     pub inside_temp: f64,