Merge pull request #631 from dalathegreat/feature/SMA-LV-CAN

New inverter protocol: SMA Low Voltage 48V via CAN

Software/USER_SETTINGS.h

@@ -46,6 +46,7 @@
 //#define PYLON_CAN        //Enable this line to emulate a "High Voltage Pylontech battery" over CAN bus
 //#define SCHNEIDER_CAN    //Enable this line to emulate a "Schneider Version 2: SE BMS" over CAN bus
 //#define SMA_CAN          //Enable this line to emulate a "BYD Battery-Box H 8.9kWh, 7 mod" over CAN bus
+//#define SMA_LV_CAN       //Enable this line to emulate a "SMA Sunny Island 48V battery" over CAN bus
 //#define SMA_TRIPOWER_CAN //Enable this line to emulate a "SMA Home Storage battery" over CAN bus
 //#define SOFAR_CAN        //Enable this line to emulate a "Sofar Energy Storage Inverter High Voltage BMS General Protocol (Extended Frame)" over CAN bus
 //#define SOLAX_CAN        //Enable this line to emulate a "SolaX Triple Power LFP" over CAN bus

Software/src/inverter/INVERTERS.h

@@ -43,6 +43,10 @@
 #include "SMA-CAN.h"
 #endif
 
+#ifdef SMA_LV_CAN
+#include "SMA-LV-CAN.h"
+#endif
+
 #ifdef SMA_TRIPOWER_CAN
 #include "SMA-TRIPOWER-CAN.h"
 #endif

Software/src/inverter/SMA-LV-CAN.cpp

@@ -0,0 +1,166 @@
+#include "../include.h"
+#ifdef SMA_LV_CAN
+#include "../datalayer/datalayer.h"
+#include "SMA-LV-CAN.h"
+
+/* SMA Sunny Island Low Voltage (48V) CAN protocol:
+CAN 2.0A
+500kBit/sec
+11-Bit Identifiers */
+
+/* Do not change code below unless you are sure what you are doing */
+static unsigned long previousMillis100ms = 0;
+
+#define VOLTAGE_OFFSET_DV 40  //Offset in deciVolt from max charge voltage and min discharge voltage
+#define MAX_VOLTAGE_DV 630
+#define MIN_VOLTAGE_DV 41
+
+//Actual content messages
+CAN_frame SMA_351 = {.FD = false,  // Battery charge voltage, charge/discharge limit, min discharge voltage
+                     .ext_ID = false,
+                     .DLC = 8,
+                     .ID = 0x351,
+                     .data = {0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00}};
+CAN_frame SMA_355 = {.FD = false,  // SOC, SOH, HiResSOC
+                     .ext_ID = false,
+                     .DLC = 8,
+                     .ID = 0x355,
+                     .data = {0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00}};
+CAN_frame SMA_356 = {.FD = false,  // Battery voltage, current, temperature
+                     .ext_ID = false,
+                     .DLC = 8,
+                     .ID = 0x356,
+                     .data = {0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00}};
+CAN_frame SMA_35A = {.FD = false,  // Alarms & Warnings
+                     .ext_ID = false,
+                     .DLC = 8,
+                     .ID = 0x35A,
+                     .data = {0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00}};
+CAN_frame SMA_35B = {.FD = false,  // Events
+                     .ext_ID = false,
+                     .DLC = 8,
+                     .ID = 0x35B,
+                     .data = {0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00}};
+CAN_frame SMA_35E = {.FD = false,  // Manufacturer ASCII
+                     .ext_ID = false,
+                     .DLC = 8,
+                     .ID = 0x35E,
+                     .data = {0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00}};
+CAN_frame SMA_35F = {.FD = false,  // Battery Type, version, capacity, ID
+                     .ext_ID = false,
+                     .DLC = 8,
+                     .ID = 0x35F,
+                     .data = {0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00}};
+CAN_frame SMA_00F = {.FD = false,  // Emergency stop message
+                     .ext_ID = false,
+                     .DLC = 8,  //Documentation unclear, should message even have any content?
+                     .ID = 0x00F,
+                     .data = {0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00}};
+
+static int16_t temperature_average = 0;
+
+void update_values_can_inverter() {  //This function maps all the values fetched from battery CAN to the correct CAN messages
+  //Calculate values
+
+  temperature_average =
+      ((datalayer.battery.status.temperature_max_dC + datalayer.battery.status.temperature_min_dC) / 2);
+
+  //Map values to CAN messages
+  //Battery charge voltage (eg 400.0V = 4000 , 16bits long) (MIN 41V, MAX 63V, default 54V)
+  SMA_351.data.u8[0] = ((datalayer.battery.info.max_design_voltage_dV - VOLTAGE_OFFSET_DV) >> 8);
+  SMA_351.data.u8[1] = ((datalayer.battery.info.max_design_voltage_dV - VOLTAGE_OFFSET_DV) & 0x00FF);
+  if (datalayer.battery.info.max_design_voltage_dV > MAX_VOLTAGE_DV) {
+    //If the battery is designed for more than 63.0V, cap the value
+    SMA_351.data.u8[0] = (MAX_VOLTAGE_DV >> 8);
+    SMA_351.data.u8[1] = (MAX_VOLTAGE_DV & 0x00FF);
+    //TODO; raise event?
+  }
+  //Discharge limited current, 500 = 50A, (0.1, A) (MIN 0, MAX 1200)
+  SMA_351.data.u8[2] = (datalayer.battery.status.max_discharge_current_dA >> 8);
+  SMA_351.data.u8[3] = (datalayer.battery.status.max_discharge_current_dA & 0x00FF);
+  //Charge limited current, 125 =12.5A (0.1, A) (MIN 0, MAX 1200)
+  SMA_351.data.u8[4] = (datalayer.battery.status.max_charge_current_dA >> 8);
+  SMA_351.data.u8[5] = (datalayer.battery.status.max_charge_current_dA & 0x00FF);
+  //Discharge voltage (eg 300.0V = 3000 , 16bits long) (MIN 41V, MAX 48V, default 41V)
+  SMA_351.data.u8[6] = ((datalayer.battery.info.min_design_voltage_dV + VOLTAGE_OFFSET_DV) >> 8);
+  SMA_351.data.u8[7] = ((datalayer.battery.info.min_design_voltage_dV + VOLTAGE_OFFSET_DV) & 0x00FF);
+  if (datalayer.battery.info.min_design_voltage_dV < MIN_VOLTAGE_DV) {
+    //If the battery is designed for discharge voltage below 41.0V, cap the value
+    SMA_351.data.u8[6] = (MIN_VOLTAGE_DV >> 8);
+    SMA_351.data.u8[7] = (MIN_VOLTAGE_DV & 0x00FF);
+    //TODO; raise event?
+  }
+
+  //SOC (100%)
+  SMA_355.data.u8[0] = ((datalayer.battery.status.reported_soc / 100) >> 8);
+  SMA_355.data.u8[1] = ((datalayer.battery.status.reported_soc / 100) & 0x00FF);
+  //StateOfHealth (100%)
+  SMA_355.data.u8[2] = ((datalayer.battery.status.soh_pptt / 100) >> 8);
+  SMA_355.data.u8[3] = ((datalayer.battery.status.soh_pptt / 100) & 0x00FF);
+  //State of charge High Precision (100.00%)
+  SMA_355.data.u8[4] = (datalayer.battery.status.reported_soc >> 8);
+  SMA_355.data.u8[5] = (datalayer.battery.status.reported_soc & 0x00FF);
+
+  //Voltage (370.0)
+  SMA_356.data.u8[0] = ((datalayer.battery.status.voltage_dV * 10) >> 8);
+  SMA_356.data.u8[1] = ((datalayer.battery.status.voltage_dV * 10) & 0x00FF);
+  //Current (S16 dA)
+  SMA_356.data.u8[2] = (datalayer.battery.status.current_dA >> 8);
+  SMA_356.data.u8[3] = (datalayer.battery.status.current_dA & 0x00FF);
+  //Temperature (s16 degC)
+  SMA_356.data.u8[4] = (temperature_average >> 8);
+  SMA_356.data.u8[5] = (temperature_average & 0x00FF);
+
+  //TODO: Map error/warnings in 0x35A
+}
+
+void receive_can_inverter(CAN_frame rx_frame) {
+  switch (rx_frame.ID) {
+    case 0x305:
+      datalayer.system.status.CAN_inverter_still_alive = CAN_STILL_ALIVE;
+      //Frame0-1 Battery Voltage
+      //Frame2-3 Battery Current
+      //Frame4-5 Battery Temperature
+      //Frame6-7 SOC Battery
+      break;
+    case 0x306:
+      datalayer.system.status.CAN_inverter_still_alive = CAN_STILL_ALIVE;
+      //Frame0-1 SOH Battery
+      //Frame2 Charging procedure
+      //Frame3 Operating state
+      //Frame4-5 Active error message
+      //Frame6-7 Battery charge voltage setpoint
+      break;
+    default:
+      break;
+  }
+}
+
+void send_can_inverter() {
+  unsigned long currentMillis = millis();
+
+  if (currentMillis - previousMillis100ms >= INTERVAL_100_MS) {
+    previousMillis100ms = currentMillis;
+
+    transmit_can(&SMA_351, can_config.inverter);
+    transmit_can(&SMA_355, can_config.inverter);
+    transmit_can(&SMA_356, can_config.inverter);
+    transmit_can(&SMA_35A, can_config.inverter);
+    transmit_can(&SMA_35B, can_config.inverter);
+    transmit_can(&SMA_35E, can_config.inverter);
+    transmit_can(&SMA_35F, can_config.inverter);
+
+    //Remote quick stop (optional)
+    if (datalayer.battery.status.bms_status == FAULT) {
+      transmit_can(&SMA_00F, can_config.inverter);
+      //After receiving this message, Sunny Island will immediately go into standby.
+      //Please send start command, to start again. Manual start is also possible.
+    }
+  }
+}
+
+void setup_inverter(void) {  // Performs one time setup at startup over CAN bus
+  strncpy(datalayer.system.info.inverter_protocol, "SMA Low Voltage (48V) protocol via CAN", 63);
+  datalayer.system.info.inverter_protocol[63] = '\0';
+}
+#endif

Software/src/inverter/SMA-LV-CAN.h

@@ -0,0 +1,13 @@
+#ifndef SMA_LV_CAN_H
+#define SMA_LV_CAN_H
+#include "../include.h"
+
+#define CAN_INVERTER_SELECTED
+
+#define READY_STATE 0x03
+#define STOP_STATE 0x02
+
+void transmit_can(CAN_frame* tx_frame, int interface);
+void setup_inverter(void);
+
+#endif