si_control.py

import requests as req
import sys
import time
from time import strftime
import crcmod
import serial
from pymodbus.constants import Endian
from pymodbus.payload import BinaryPayloadDecoder
from pymodbus.client.sync import ModbusTcpClient as ModbusClient
from pymodbus.diag_message import *
from pymodbus.file_message import *
from pymodbus.other_message import *
from pymodbus.mei_message import *
import struct
from binascii import unhexlify

# Limit inverter power
maxpower = 2200
minpower = 2200
# Declare
si_power = 0
si_volt = 0
wh_daily = 0


def set_power(grid, PV, charger, si_power, action):
    # Send to iobroker values for diagram purposes
    url = 'http://localhost:8087/set/vis.0.'
    resp = req.get(url + 'Grid' + '?value=' + str(grid))
    resp = req.get(url + 'PV' + '?value=' + str(PV))
    resp = req.get(url + 'control_status' + '?value=' + action)
    if charger < 0 and si_power < 0:
        req.get(url + 'Batt_Charge' + '?value=' + str(-si_power))
        req.get(url + 'Batt_Discharge' + '?value=' + str(0))
    elif charger > 0:
        req.get(url + 'Batt_Charge' + '?value=' + str(0))
        if si_power > 0:
            req.get(url + 'Batt_Discharge' + '?value=' + str(si_power))
    else:
        req.get(url + 'Batt_Charge' + '?value=' + str(0))
        req.get(url + 'Batt_Discharge' + '?value=' + str(0))
    return ()


def get_wh_daily(wh_total, today):
    if int(strftime("%d", time.localtime())) != today:  # New Day
        today = int(strftime("%d", time.localtime()))  # Change day
        wh_total = GET_SI_WH()  # Reference total counter
    wh_day = GET_SI_WH() - wh_total  # Calculate current daily
    url = 'http://localhost:8087/set/vis.0.'
    resp = req.get(url + 'wh_day' + '?value=' + str(wh_day))
    resp = req.get(url + 'SI_Wh_total' + '?value=' + str(wh_total))
    return (wh_total, wh_day, today)


# POSITIVE means discharge battery
def build_data(pow):
    crc16_modbus = crcmod.mkCrcFun(0x18005, rev=True, initCrc=0xFFFF, xorOut=0x0000)
    if pow >= 0:
        power = str('%04X' % (pow))
    else:
        pow = -pow
        power = str('8''%03X' % (pow))
    Adr = '0B3F0D'
    # Rest = '01f9021c00960000000000' #50.5V 54V
    #  Rest = '01f9023500960000000000' #50.5V 56.5V
    Rest = '01e0023500960000000000'  # 48 56.5V
    # Rest = '01f9023000960000000000' #50.5V 56V
    # Rest = '01f9022100960000000000' #50.5V 54.5V
    # Rest = '01f9022b00960000000000' #50.5V 55.5V
    # Rest = '01f9021900960000000000' #50.5V 53.7V
    data = (Adr + str(power) + Rest)
    crc = (crc16_modbus(data.decode('hex')))
    crch = (crc & 0xff)
    crcl = (((crc >> 8) & 0xff))
    crchst = ('%02X' % crch)
    crclst = ('%02X' % crcl)
    Send = (data.decode('hex')) + (crchst.decode('hex')) + crclst.decode('hex')
    return Send


def GET_SI():
    Anfr33 = '0b330101325f'
    ser.write(Anfr33.decode('hex'))
    time.sleep(0.1)
    Antw33 = ser.read(42)
    Antw33h = Antw33.encode('hex')
    #print('Sent %s read %s' % (Anfr33, Antw33h))
    reply_ID = (Antw33.encode('hex')[2:4])
    if (reply_ID) == '3f':
        #Chop off 0b3f0101f25c bytes
        Antw33 = Antw33[6:41]
        #print('Chopped to %s' % Antw33.encode('hex'))
        reply_ID = (Antw33.encode('hex')[2:4])

    if reply_ID == '33':
        batp = (Antw33.encode('hex')[20:24])
        batu = (Antw33.encode('hex')[6:10])
        try:
            si_power = struct.unpack('>H', unhexlify(batp))[0]
            si_volt = struct.unpack('>H', unhexlify(batu))[0] * 0.108
        except:
            si_volt = 0
            si_power = 0
            time_s = strftime("%y/%m/%d %H:%M:%S ", time.localtime())
            print('%s Wrong feedback from Battery Inverter' % (time_s))
        if si_power > 25000:  # negative value comes with twos compl
            si_power = -(-32768 + si_power) * 0.1
        else:
            si_power = si_power * 0.1
    else:  # no update possible
        si_power = 12345
        si_volt = 12345
        # print('SI does not answer to request, setting fdb to 12345')
    #print('Power read SI %d ' % si_power)
    return (si_power, si_volt)


def GET_SI_WH():
    Anfr3E = '0b3e0101a39c'
    ser.write(Anfr3E.decode('hex'))
    time.sleep(0.1)
    Antw3E = ser.read(38)
    # Antw3Eh = Antw3E.encode('hex')
    # print ('Sent %s read %s'%(Anfr3E,Antw3Eh))
    NRG = (Antw3E.encode('hex')[18:26])
    NRG = int(NRG, 16) / 36000
    # print ('%f kWh total' % NRG)
    return (NRG)


time.sleep(10)
# Define RS485 serial port
ser = serial.Serial(
    port='/dev/ttyUSB0',
    baudrate=57600,
    parity=serial.PARITY_NONE,
    stopbits=serial.STOPBITS_ONE,
    bytesize=serial.EIGHTBITS,
    timeout=0)

# Connect to inverter
ip = '192.168.0.71'  # This is the ip from your fronius inverter
client = ModbusClient(ip, port=502)
client.connect()

load = 0  # (+)
pv = 0  # (+)
grid = int(0)  # Total going to GRID
charger = int(10)
charger_old = 0
batt_full_flag = 0
batt_empty_flag = 0
SoC_target_int = 90
SoC_min_target_int = 15
count = 0
AVM = 0
si_power = 0
si_volt = 0
# try:
#   wh_total=GET_SI_WH()
# except:
#   print("WH_TOTAL funtion call error")
wh_total = 0;
today = int(strftime("%M", time.localtime()))
while 1:
    try:
        BMS_SoC = int(req.get('http://localhost:8087/getPlainValue/vis.0.SoC').text)
    except:
        BMS_SoC = 0  # Default to meas. Voltage based SoC if BMS_SoC not available
    # GET GRID VALUE from SMARTMETER
    try:
        value = client.read_holding_registers(40098 - 1, 2, unit=240)
        smACPower = BinaryPayloadDecoder.fromRegisters(value.registers, byteorder=Endian.Big,
                                                       wordorder=Endian.Big)
        grid = int(smACPower.decode_32bit_float())
    except:
        time_s = strftime("%y/%m/%d %H:%M:%S ", time.localtime())
        print('%s WARNING Modbus smartmeter not answering' % (time_s))
    try:
        value = client.read_holding_registers(40092 - 1, 2, unit=1)
        sf = BinaryPayloadDecoder.fromRegisters(value.registers, byteorder=Endian.Big,
                                                wordorder=Endian.Big)
        pv = int(sf.decode_32bit_float())
    except:
        time_s = strftime("%y/%m/%d %H:%M:%S ", time.localtime())
        print('%s WARNING Modbus Inverter not answering' % (time_s))
    try:  # Read from iobroker the user whised max SoC
        SoC_target = int(req.get('http://localhost:8087/getPlainValue/vis.0.SoC_target').text)
        if SoC_target > 10 and SoC_target <= 100 and SoC_target != SoC_target_int:
            SoC_target_int = SoC_target
            batt_full_flag = 0
            time_s = strftime("%y/%m/%d %H:%M:%S ", time.localtime())
            print('%s updating SoC Target' % (time_s))
    except:
        pass
    try:  # Read from Iobroker the user wished min SoC
        SoC_min_target = int(req.get('http://localhost:8087/getPlainValue/vis.0.SoC_min_target').text)
        if SoC_min_target >= 0 and SoC_min_target <= 100 and SoC_min_target != SoC__min_target_int:
            SoC_min_target_int = SoC_min_target
    except:
        pass

    # control loop start here
    if grid < -10 and batt_full_flag == 0:
        charger -= 2  # slowly increment charger
        if grid < -80:
            charger += grid  # setpoint charger
        if grid < -20:
            charger -= 10
        if charger < 0:
            action = "Inc.Charg"
        else:
            action = "Dec.Supply"
        if charger <= -minpower:  # Upper limit
            charger = -minpower
            action = "Charg.Max"
        if BMS_SoC >= SoC_target_int:  # Batt. full
            charger = 0
            action = "Max.SoC"
            batt_full_flag = 1
            time_s = strftime("%y/%m/%d %H:%M:%S ", time.localtime())
            print('%s Batt Full' % (time_s))

    elif grid > 10:
        charger += grid  # setpoint charger
        action = "Inc.Supply"
        if charger > maxpower:  # Lower limit
            charger = maxpower
            action = "Suppl.Max"
        if BMS_SoC < (SoC_target - 2) and batt_full_flag == 1:
            batt_full_flag = 0


    elif batt_full_flag == 1 and grid < 0:  # and pv > 150: #Batt Full and PV available
        if charger > 0:  # Grid injection is not coming from PV but from Supply
            charger += grid  # Supply less
            action = "Decr.Supply"
        else:
            charger = 0  # Supply was off, Turn SI OFF
        action = "Batt_Full"
    else:
        action = "Opt._Ctrl"

    # Avoid toggling after big load turns off and system changes from supply to charge
    # even though PV is not enough (or even 0)
    if (pv + charger) < 0:  # if charger bigger than photovoltaik
        time_s = strftime("%y/%m/%d %H:%M:%S", time.localtime())
        # print ('%s Avoid toggle charger %d pv %d' %(time_s,charger,pv))
        charger = -pv
        if pv == 0:
            charger = - 100  # keep supplying something, avoid turning SI off

    # Battery lower limit
    if BMS_SoC <= SoC_min_target:
        batt_empty_flag = 1
    if BMS_SoC > (SoC_min_target + 2):
        batt_empty_flag = 0
    if (charger > 0) and (batt_empty_flag == 1):
        charger = 0  # Stop discharging the battery
        action = "Empty"

    (si_power_new, si_volt_new) = GET_SI()
    # print('charger value',charger)
    if si_power_new != 12345:  # Updated values available
        si_power = si_power_new
        si_volt = si_volt_new
    elif charger == 0:  # Looks like no updates du to inverter turned off
        print ('Setting SI Power to zero since it does not update feedback')
        si_power = 0  # so setting the value to zero for nice plots

    set_power(grid, pv, charger, si_power, action)
    if count == 5:
        try:
            (wh_total, wh_daily, today) = get_wh_daily(wh_total, today)
            count = 0
        except:
            AVM = -9999
    else:
        count += 1
    if charger > 0:
        modus = "Supply"
    else:
        modus = "Charge"
    # if charger >-100 and charger_old >-100 : #Do not charge if lower than 100 W (efficiency very bad)
    #  charger = 0

    # VERBOSE MODE for logging to file
    time_s = strftime("%y/%m/%d %H:%M:%S ", time.localtime())
#    print ('%s%s %04d act %04.0f PV %04d GRID %04d PACK %05.2f SoC %2.1f Wh day %d total %d Wh %s'
#            %(time_s, modus, charger, si_power, pv, grid, si_volt, BMS_SoC , wh_daily, wh_total, action))
    data_stream = build_data(charger)
    test = data_stream.encode('hex')
    ser.write(test.decode('hex'))
    if (charger_old >= 0 and charger < 0) or (charger_old <= 0 and charger > 0):
        time.sleep(15)
        print("MOde switch, wait 15s")
    else:
        time.sleep(2)
    charger_old = charger  # Remember last cycle mode
client.close()