Fixed basic nanogrid port implementation

Instead of SOLAR_TERMINAL, GRID_TERMINAL has to be defined in config.h
(see also template).

Author: martinjaeger

src/config.h_template

@@ -7,16 +7,27 @@
 #ifndef CONFIG_H
 #define CONFIG_H
 
+#include "pcb.h"
+
 /** @file
  *
  * @brief
  * Used to define personal settings, e.g. which type of interface at the UEXT port should be used.
  */
 
+// typical MPPT buck mode / PWM charge controller
 #define DCDC_MODE_INIT      MODE_MPPT_BUCK
+#if FEATURE_PWM_SWITCH
+#define SOLAR_TERMINAL      pwm_terminal
+#else
+#define SOLAR_TERMINAL      hv_terminal
+#endif
+
+// Nanogrid mode
 //#define DCDC_MODE_INIT      MODE_NANOGRID
+//#define GRID_TERMINAL       hv_terminal
 
-#define SOLAR_TERMINAL      hv_terminal
+// battery always assumed to be at low-voltage terminal (might need to be changed for boost mode)
 #define BATTERY_TERMINAL    lv_terminal
 
 // basic battery configuration

src/data_objects.cpp

@@ -115,7 +115,9 @@ const data_object_t data_objects[] = {
 
     // battery related data objects
     {0x70, TS_OUTPUT, TS_READ_ALL, TS_T_FLOAT32, 2, (void*) &(bat_terminal.voltage),                    "Bat_V"},
+#ifdef SOLAR_TERMINAL
     {0x71, TS_OUTPUT, TS_READ_ALL, TS_T_FLOAT32, 2, (void*) &(solar_terminal.voltage),                  "Solar_V"},
+#endif
     {0x72, TS_OUTPUT, TS_READ_ALL, TS_T_FLOAT32, 2, (void*) &(bat_terminal.current),                    "Bat_A"},
     {0x73, TS_OUTPUT, TS_READ_ALL, TS_T_FLOAT32, 2, (void*) &(load_terminal.current),                   "Load_A"},
     {0x74, TS_OUTPUT, TS_READ_ALL, TS_T_FLOAT32, 1, (void*) &(charger.bat_temperature),                 "Bat_degC"},
@@ -128,11 +130,15 @@ const data_object_t data_objects[] = {
 #if FEATURE_DCDC_CONVERTER
     {0x79, TS_OUTPUT, TS_READ_ALL, TS_T_UINT16,  0, (void*) &(dcdc.state),                              "DCDCState"},
 #endif
+#ifdef SOLAR_TERMINAL
     {0x7A, TS_OUTPUT, TS_READ_ALL, TS_T_FLOAT32, 2, (void*) &(solar_terminal.current),                  "Solar_A"},
+#endif
     {0x7B, TS_OUTPUT, TS_READ_ALL, TS_T_FLOAT32, 2, (void*) &(bat_terminal.sink_voltage_max),           "BatTarget_V"},
     {0x7C, TS_OUTPUT, TS_READ_ALL, TS_T_FLOAT32, 2, (void*) &(bat_terminal.pos_current_limit),          "BatTarget_A"},
     {0x7D, TS_OUTPUT, TS_READ_ALL, TS_T_FLOAT32, 2, (void*) &(bat_terminal.power),                      "Bat_W"},
+#ifdef SOLAR_TERMINAL
     {0x7E, TS_OUTPUT, TS_READ_ALL, TS_T_FLOAT32, 2, (void*) &(solar_terminal.power),                    "Solar_W"},
+#endif
     {0x7F, TS_OUTPUT, TS_READ_ALL, TS_T_FLOAT32, 2, (void*) &(load_terminal.power),                     "Load_W"},
 
     {0x90, TS_OUTPUT, TS_READ_ALL, TS_T_UINT32,  0, (void*) &(dev_stat.error_flags),                    "ErrorFlags"},
@@ -151,7 +157,9 @@ const data_object_t data_objects[] = {
     {0x10, TS_REC, TS_READ_ALL | TS_WRITE_MAKER, TS_T_UINT16,  0, (void*) &(dev_stat.load_power_max_day),           "LoadMaxDay_W"},
 
     // accumulated data
+#ifdef SOLAR_TERMINAL
     {0xA0, TS_REC, TS_READ_ALL | TS_WRITE_MAKER, TS_T_FLOAT32, 2, (void*) &(solar_terminal.neg_energy_Wh),          "SolarInDay_Wh"},
+#endif
     {0xA1, TS_REC, TS_READ_ALL | TS_WRITE_MAKER, TS_T_FLOAT32, 2, (void*) &(load_terminal.pos_energy_Wh),           "LoadOutDay_Wh"},
     {0xA2, TS_REC, TS_READ_ALL | TS_WRITE_MAKER, TS_T_FLOAT32, 2, (void*) &(bat_terminal.pos_energy_Wh),            "BatChgDay_Wh"},
     {0xA3, TS_REC, TS_READ_ALL | TS_WRITE_MAKER, TS_T_FLOAT32, 2, (void*) &(bat_terminal.neg_energy_Wh),            "BatDisDay_Wh"},

src/dcdc.cpp

@@ -77,19 +77,16 @@ int Dcdc::duty_cycle_delta()
         out->sink_voltage_max, out->pos_current_limit, half_bridge_get_duty_cycle() * 100.0,
         state);
 
-    if (time(NULL) - power_good_timestamp > 10 ||      // more than 10s low power
-         out->power < -1.0)           // or already generating negative power
-    {
-        pwr_inc_goal = 0;     // switch off
+    if ((time(NULL) - power_good_timestamp > 10 || out->power < -1.0) && mode != MODE_NANOGRID) {
+        // swith off after 10s low power or negative power (if not in nanogrid mode)
+        pwr_inc_goal = 0;
     }
-    else if (out->voltage > (out->sink_voltage_max - out->pos_droop_res * out->current))
-    {
-       // output voltage target reached
+    else if (out->voltage > (out->sink_voltage_max - out->pos_droop_res * out->current)) {
+        // output voltage target reached
         state = DCDC_STATE_CV;
         pwr_inc_goal = -1;  // decrease output power
     }
-    else if (out->current > out->pos_current_limit)
-    {
+    else if (out->current > out->pos_current_limit) {
         // output charge current limit reached
         state = DCDC_STATE_CC;
         pwr_inc_goal = -1;  // decrease output power
@@ -103,8 +100,7 @@ int Dcdc::duty_cycle_delta()
         state = DCDC_STATE_DERATING;
         pwr_inc_goal = -1;  // decrease output power
     }
-    else if (out->power < output_power_min && out->voltage < out->src_voltage_start)
-    {
+    else if (out->power < output_power_min && out->voltage < out->src_voltage_start) {
         // no load condition (e.g. start-up of nanogrid) --> raise voltage
         pwr_inc_goal = 1;   // increase output power
     }

src/device_status.cpp

@@ -27,6 +27,7 @@ void DeviceStatus::update_energy()
     static uint32_t bat_chg_total_Wh_prev = bat_chg_total_Wh;
     static uint32_t bat_dis_total_Wh_prev = bat_dis_total_Wh;
 
+#ifdef SOLAR_TERMINAL
     if (solar_terminal.voltage < bat_terminal.voltage) {
         seconds_zero_solar += 1;
     }
@@ -47,13 +48,16 @@ void DeviceStatus::update_energy()
         }
         seconds_zero_solar = 0;
     }
+#endif
 
     bat_chg_total_Wh = bat_chg_total_Wh_prev +
         (bat_terminal.pos_energy_Wh > 0 ? bat_terminal.pos_energy_Wh : 0);
     bat_dis_total_Wh = bat_dis_total_Wh_prev +
         (bat_terminal.neg_energy_Wh > 0 ? bat_terminal.neg_energy_Wh : 0);
+#ifdef SOLAR_TERMINAL
     solar_in_total_Wh = solar_in_total_Wh_prev +
         (solar_terminal.neg_energy_Wh > 0 ? solar_terminal.neg_energy_Wh : 0);
+#endif
     load_out_total_Wh = load_out_total_Wh_prev +
         (load_terminal.pos_energy_Wh > 0 ? load_terminal.pos_energy_Wh : 0);
 }
@@ -64,9 +68,11 @@ void DeviceStatus::update_min_max_values()
         battery_voltage_max = bat_terminal.voltage;
     }
 
+#ifdef SOLAR_TERMINAL
     if (solar_terminal.voltage > solar_voltage_max) {
         solar_voltage_max = solar_terminal.voltage;
     }
+#endif
 
 #if FEATURE_DCDC_CONVERTER
     if (dcdc.lvs->current > dcdc_current_max) {
@@ -82,12 +88,14 @@ void DeviceStatus::update_min_max_values()
         load_current_max = load_terminal.current;
     }
 
+#ifdef SOLAR_TERMINAL
     if (-solar_terminal.power > solar_power_max_day) {
         solar_power_max_day = -solar_terminal.power;
         if (solar_power_max_day > solar_power_max_total) {
             solar_power_max_total = solar_power_max_day;
         }
     }
+#endif
 
     if (load_terminal.power > load_power_max_day) {
         load_power_max_day = load_terminal.power;

src/ext/oled.cpp

@@ -75,6 +75,12 @@ void ExtOled::process_1s()
     char buf[30];
     unsigned int len;
 
+#ifdef SOLAR_TERMINAL
+    PowerPort &in_terminal = solar_terminal;
+#elif defined(GRID_TERMINAL)
+    PowerPort &in_terminal = grid_terminal;
+#endif
+
     oled.clear();
 
     oled.drawBitmap(6, 0, bmp_pv_panel, 16, 16, 1);
@@ -121,7 +127,7 @@ void ExtOled::process_1s()
 #endif
         oled.setTextCursor(0, 18);
         len = snprintf(buf, sizeof(buf), "%4.0fW",
-            (abs(solar_terminal.power) < 1) ? 0 : -solar_terminal.power);  // remove negative zeros
+            (abs(in_terminal.power) < 1) ? 0 : -in_terminal.power);  // remove negative zeros
         oled.writeString(buf, len);
     }
     else {
@@ -130,11 +136,11 @@ void ExtOled::process_1s()
         oled.writeString(buf, len);
     }
 #ifndef CHARGER_TYPE_PWM
-    if (solar_terminal.voltage > bat_terminal.voltage)
+    if (in_terminal.voltage > bat_terminal.voltage)
 #endif
     {
         oled.setTextCursor(0, 26);
-        len = snprintf(buf, sizeof(buf), "%4.1fV", solar_terminal.voltage);
+        len = snprintf(buf, sizeof(buf), "%4.1fV", in_terminal.voltage);
         oled.writeString(buf, len);
     }
 
@@ -159,7 +165,7 @@ void ExtOled::process_1s()
 
     oled.setTextCursor(0, 36);
     len = snprintf(buf, sizeof(buf), "Day +%5.0fWh -%5.0fWh",
-        solar_terminal.neg_energy_Wh, fabs(load_terminal.pos_energy_Wh));
+        in_terminal.neg_energy_Wh, fabs(load_terminal.pos_energy_Wh));
     oled.writeString(buf, len);
     len = snprintf(buf, sizeof(buf), "Tot +%4.1fkWh -%4.1fkWh",
         dev_stat.solar_in_total_Wh / 1000.0, fabs(dev_stat.load_out_total_Wh) / 1000.0);

src/main.h

@@ -33,6 +33,7 @@ extern PwmSwitch pwm_switch;
 
 extern PowerPort &bat_terminal;
 extern PowerPort &solar_terminal;
+extern PowerPort &grid_terminal;
 
 extern DeviceStatus dev_stat;
 extern Charger charger;

src/main_mbed.cpp

@@ -46,19 +46,21 @@ Dcdc dcdc(&hv_terminal, &dcdc_lv_port, DCDC_MODE_INIT);
 PowerPort pwm_terminal;         // external terminal of PWM switch port (normally solar)
 PowerPort pwm_port_int;         // internal side of PWM switch
 PwmSwitch pwm_switch(&pwm_terminal, &pwm_port_int);
-PowerPort &solar_terminal = pwm_terminal;
-#else
-PowerPort &solar_terminal = SOLAR_TERMINAL;     // defined in config.h
 #endif
 
 #if FEATURE_LOAD_OUTPUT
 PowerPort load_terminal;        // load terminal (also connected to lv_bus)
 LoadOutput load(&load_terminal);
 #endif
 
+#ifdef SOLAR_TERMINAL
+PowerPort &solar_terminal = SOLAR_TERMINAL;     // defined in config.h
+#endif
+
 PowerPort &bat_terminal = BATTERY_TERMINAL;     // defined in config.h
+
 #ifdef GRID_TERMINAL
-PowerPort &grid_terminal = GRID_TERMINAL;
+PowerPort &grid_terminal = GRID_TERMINAL;       // defined in config.h
 #endif
 
 Charger charger(&bat_terminal);
@@ -106,7 +108,9 @@ int main()
 
     init_watchdog(10);      // 10s should be enough for communication ports
 
+    #ifdef SOLAR_TERMINAL
     solar_terminal.init_solar();
+    #endif
 
     #ifdef GRID_TERMINAL
     grid_terminal.init_nanogrid();
@@ -191,8 +195,16 @@ void system_control()
         // see also here: https://github.com/ARMmbed/mbed-os/issues/9065
         timestamp++;
         counter = 0;
+
         // energy + soc calculation must be called exactly once per second
+        #ifdef SOLAR_TERMINAL
         solar_terminal.energy_balance();
+        #endif
+
+        #ifdef GRID_TERMINAL
+        grid_terminal.energy_balance();
+        #endif
+
         bat_terminal.energy_balance();
         load_terminal.energy_balance();
         dev_stat.update_energy();

src/power_port.cpp

@@ -26,7 +26,7 @@ void PowerPort::init_nanogrid()
 
     // also initialize the connected bus
     src_voltage_start = 30.0;       // starting buck mode above this point
-    src_voltage_stop = 20.0;        // stopping buck mode below this point
+    src_voltage_stop = 30.0;        // stopping buck mode below this point
 
     sink_voltage_max = 28.0;     // starting idle mode above this point
     sink_voltage_min = 10.0;