def steady_state_model(self, t):
"""Grid voltage change."""
Vagrid_new, wgrid_new = self.events.grid_events(t)
Vagrid_new = Vagrid_new * (self.Vgridrated / self.Vbase)
if abs(self.Vagrid -
Vagrid_new) > 0.0 and t >= self._t_voltage_previous:
utility_functions.print_to_terminal(
"{}:Grid voltage changed from {:.3f} V to {:.3f} V at {:.3f} s"
.format(self.name, self.Vagrid, Vagrid_new, t))
self.Vagrid = Vagrid_new
self.Vbgrid = utility_functions.Ub_calc(self.Vagrid *
self.unbalance_ratio_b)
self.Vcgrid = utility_functions.Uc_calc(self.Vagrid *
self.unbalance_ratio_c)
self._t_voltage_previous = t
if abs(self.wgrid -
wgrid_new) > 0.0 and t >= self._t_frequency_previous:
utility_functions.print_to_terminal(
"{}:Grid frequency changed from {:.3f} Hz to {:.3f} Hz at {:.3f} s"
.format(self.name, self.wgrid / (2.0 * math.pi),
wgrid_new / (2.0 * math.pi), t))
self.wgrid = wgrid_new
self._t_frequency_previous = t
self.vag = self.Vagrid
self.vbg = self.Vbgrid
self.vcg = self.Vcgrid
def print_event(self,text_string,print_inline):
"""Print information about ride through events."""
if text_string != '':
if print_inline: #Print in notebook window
logging.info(text_string)
else: #Print in console window
utility_functions.print_to_terminal(text_string)
else:
pass
def update_Zload1(self, t):
"""Update load impedance at PCC-LV side."""
if self.standAlone: #Update load at PCC LV side only in stand alone mode
Zload1_actual_new = self.events.load_events(t)
Zload1_new = Zload1_actual_new / BaseValues.Zbase
if abs(self.Zload1 - Zload1_new) > 0.0:
self.Zload1 = Zload1_new
utility_functions.print_to_terminal(
"Load at PCC LV side changed from {:.3f} VA to {:.3f} VA at {:.3f}"
.format(self.S_load1, self.S_load1_calc(), t))
def update_Ppv(self, t):
"""Update PV module power output based on solar events and DC link voltage."""
Sinsol_new, Tactual_new = self.events.solar_events(t)
if abs(self.Sinsol - Sinsol_new
) or abs(self.Tactual - Tactual_new
) > 0.0: #Update Iph only if solar insolation changes
self.Sinsol = Sinsol_new
self.Tactual = Tactual_new
utility_functions.print_to_terminal(
"{}:PV module current output changed from {:.3f} A to {:.3f} A at {:.3f} s"
.format(self.name, self.Iph, self.Iph_calc(), t))
self.Iph = self.Iph_calc()
self.Ppv = self.Ppv_calc(self.Vdc_actual)
def Volt_VAR_logic(self, t):
""" Volt-VAR."""
#Select RMS voltage source
Vrms_measured = self.Vrms
self.Qlimit = self.Qlimit_calc()
deadband_V = 0.01
if t > self.Volt_VAR_logic_t: #Update volt-var logic only if solver time is greater that current time
self.Volt_VAR_logic_t = t
if self.VOLT_VAR_ACTIVE:
if self.Volt_VAR_inject_range(Vrms_measured, deadband_V):
Qref = self.Q_Volt_VAR_inject(Vrms_measured)
elif self.Volt_VAR_absorb_range(Vrms_measured, deadband_V):
Qref = self.Q_Volt_VAR_absorb(Vrms_measured)
else:
utility_functions.print_to_terminal(
"Volt-VAR control with reference voltage {:.3f} is deactivated at {:.3f} s for {:.3f} V"
.format(self.Vrms_ref * self.Vbase, t,
Vrms_measured * self.Vbase))
Qref = 0.0
self.VOLT_VAR_ACTIVE = False
else:
if self.Volt_VAR_inject_range(Vrms_measured, deadband_V):
Qref = self.Q_Volt_VAR_inject(Vrms_measured)
utility_functions.print_to_terminal(
"Volt-VAR control (injection) with reference voltage {:.3f} is activated at {:.3f} s for {:.3f} V"
.format(self.Vrms_ref * self.Vbase, t,
Vrms_measured * self.Vbase))
self.VOLT_VAR_ACTIVE = True
elif self.Volt_VAR_absorb_range(Vrms_measured, deadband_V):
Qref = self.Q_Volt_VAR_absorb(Vrms_measured)
utility_functions.print_to_terminal(
"Volt-VAR control (absorbption) with reference voltage {:.3f} is activated at {:.3f} s for {:.3f} V"
.format(self.Vrms_ref * self.Vbase, t,
Vrms_measured * self.Vbase))
self.VOLT_VAR_ACTIVE = True
else: #Don't supply/absorb reactive power outside operating range
Qref = 0.0
else:
self.Volt_VAR_logic_t = self.Volt_VAR_logic_t
Qref = self.Q_ref
return Qref
def Volt_VAR_logic(self,t):
"""Function for volt_var control."""
assert not (self.VOLT_VAR_ENABLE and self.VOLT_WATT_ENABLE), "Volt-VAR and Volt-Watt cannot be active at the same time"
#Volt-VAR logic
V1_Volt_VAR = self.Vrms_ref - 0.04*self.Vrms_ref #From IEEE 1547-2018 Catergy B (Table 8 - page 39)
V2_Volt_VAR = self.Vrms_ref - 0.01*self.Vrms_ref #From IEEE 1547-2018 Catergy B (Table 8 - page 39)
V3_Volt_VAR = self.Vrms_ref + 0.01*self.Vrms_ref #From IEEE 1547-2018 Catergy B (Table 8 - page 39)
V4_Volt_VAR = self.Vrms_ref + 0.04*self.Vrms_ref #From IEEE 1547-2018 Catergy B (Table 8 - page 39)
#Select RMS voltage source
_Vrms_measured = self.Vrms
_del_V = 0.02
if self.VOLT_VAR_ENABLE and (_Vrms_measured < V2_Volt_VAR or _Vrms_measured > V3_Volt_VAR) and t>self.t_stable:
if self.VOLT_VAR_FLAG:
if (_Vrms_measured > V1_Volt_VAR - _del_V and _Vrms_measured < V4_Volt_VAR + _del_V):
Qref = self.Qsetpoint_calc(t)
else:
utility_functions.print_to_terminal("Volt-VAR control with reference voltage {:.3f} is deactivated at {:.3f} s for {:.3f} V".format(self.Vrms_ref*self.Vbase,t,_Vrms_measured*self.Vbase))
Qref = 0.0
self.VOLT_VAR_FLAG = False
else:
if ( _Vrms_measured >= V1_Volt_VAR and _Vrms_measured < V4_Volt_VAR):
utility_functions.print_to_terminal("Volt-VAR control with reference voltage {:.3f} is activated at {:.3f} s for {:.3f} V".format(self.Vrms_ref*self.Vbase,t,_Vrms_measured*self.Vbase))
self.VOLT_VAR_FLAG = True
Qref = self.Qsetpoint_calc(t)
else:
utility_functions.print_to_terminal("Volt-VAR control not activated at {:.3f} s since {:.3f} V is outside range!".format(t,_Vrms_measured*self.Vbase))
Qref = 0.0
else:
Qref = 0.0
return Qref
def FRT(self,t):
"""Frequency ride through and trip logic. """
t_reconnect_limit = 3.0 #Time lag before reconnecting
#IEEE 1547-2018 standards
F_LF1 = 57.0 #From IEEE 1557-2018 Category III
F_LF2 = 58.8 #From IEEE 1557-2018 Category III
t_LF1_limit = 0.16 #Time limit for LF1 zone From IEEE 1557-2018 Category III (Table 19 and figure H10)
t_LF2_limit = 299.0 #Time limit for LF2 zone From IEEE 1557-2018 Category III (Table 19 and figure H10)
#Dummy variables to preserve logic
F_LF3 = 0.0
t_LF3_limit = 0.0
del_f =0.02
assert (F_LF1 < F_LF2) and (t_LF1_limit < t_LF2_limit), "Frequency level 2 should be greater than frequency level 1"
#Use grid frequency as estimated by PLL
fgrid = self.we/(2.0*math.pi)
if self.LFRT_ENABLE and t > self.t_stable and not self.LFRT_TRIP:
if self.LFRT_DEBUG:
text_string = '{time_stamp:.4f} -- fgrid:{f1:.3f} Hz, t_LF1start:{t1:.3f} s, t_LF2start:{t2:.3f} s, t_LF3start:{t3:.3f} s'\
.format(time_stamp=t,f1 = fgrid,t1=self.t_LF1start,t2=self.t_LF2start,t3=self.t_LF3start)
utility_functions.print_to_terminal(text_string)
if self.t_LF1start == 0.0 or self.t_LF2start == 0.0 or self.t_LF3start == 0.0:
if self.t_LF1start == 0.0 and fgrid < F_LF1:
self.t_LF1start = t
utility_functions.print_LFRT_events(t,fgrid,self.t_LF1start,event_name='LF1_start')
if self.t_LF2start == 0.0 and fgrid < F_LF2:
self.t_LF2start = t
utility_functions.print_LFRT_events(t,fgrid,self.t_LF2start,event_name='LF2_start')
if self.t_LF3start == 0.0 and fgrid < F_LF3:
self.t_LF3start = t
utility_functions.print_LFRT_events(t,fgrid,self.t_LF3start,event_name='LF3_start')
if self.t_LF1start > 0.0 or self.t_LF2start > 0.0 or self.t_LF3start > 0.0:
if fgrid >= F_LF1+del_f or fgrid >= F_LF2+del_f or fgrid >= F_LF3+del_f:
if fgrid >= F_LF1+del_f and self.t_LF1start > 0.0:
utility_functions.print_LFRT_events(t,fgrid,self.t_LF1start,event_name='LF1_reset')
self.t_LF1start = 0.0
if fgrid >= F_LF2+del_f and self.t_LF2start > 0.0:
utility_functions.print_LFRT_events(t,fgrid,self.t_LF2start,event_name='LF2_reset')
self.t_LF2start = 0.0
if fgrid >= F_LF3+del_f and self.t_LF3start > 0.0:
utility_functions.print_LFRT_events(t,fgrid,self.t_LF3start,event_name='LF3_reset')
self.t_LF3start = 0.0
if t-self.t_LF1start >= t_LF1_limit and self.t_LF1start > 0.0: #Trip inverter if any limit breached
utility_functions.print_LFRT_events(t,fgrid,self.t_LF1start,event_name='inverter_trip_LF1')
#six.print_(t-self.t_LF1start)
self.LFRT_trip_signals()
elif t-self.t_LF2start >= t_LF2_limit and self.t_LF2start > 0.0:
utility_functions.print_LFRT_events(t,fgrid,self.t_LF2start,event_name='inverter_trip_LF2')
self.LFRT_trip_signals()
elif t-self.t_LF3start >= t_LF3_limit and self.t_LF3start > 0.0:
utility_functions.print_LFRT_events(t,fgrid,self.t_LF3start,event_name='inverter_trip_LF3')
self.LFRT_trip_signals()
if fgrid < F_LF1 and self.t_LF1start > 0.0:
utility_functions.print_LFRT_events(t,fgrid,self.t_LF1start,event_name='LF1_zone') #,verbose = False
if fgrid < F_LF2 and self.t_LF2start > 0.0:
utility_functions.print_LFRT_events(t,fgrid,self.t_LF2start,event_name='LF2_zone')
if fgrid < F_LF3 and self.t_LF3start > 0.0:
utility_functions.print_LFRT_events(t,fgrid,self.t_LF3start,event_name='LF3_zone')
#six.print_(self.t_LF2start)
elif self.LFRT_ENABLE and t > self.t_stable and self.LFRT_TRIP:
if self.t_LF_reconnect > 0.0:
if fgrid < F_LF3:
utility_functions.print_LFRT_events(t,fgrid,self.t_LF_reconnect,event_name='reconnect_reset')
self.t_LF_reconnect = 0.0
elif fgrid >= F_LF3 and t-self.t_LF_reconnect >= t_reconnect_limit:
utility_functions.print_LFRT_events(t,fgrid,self.t_LF_reconnect,event_name='inverter_reconnection')
self.LFRT_TRIP = False #Reset trip flag
self.LFRT_RECONNECT = True #Set reconnect flag
self.t_LF_reconnect = 0.0 #Reset timer
elif fgrid >= F_LF3 and t-self.t_LF_reconnect < t_reconnect_limit:
utility_functions.print_LFRT_events(t,fgrid,self.t_LF_reconnect,event_name='reconnect_zone')
elif self.t_LF_reconnect == 0.0:
if fgrid >= F_LF3:
self.t_LF_reconnect = t
utility_functions.print_LFRT_events(t,fgrid,self.t_LF_reconnect,event_name='reconnect_start')
else:
utility_functions.print_LFRT_events(t,fgrid,event_name='inverter_tripped')
else:
self.t_LF1start = 0.0
self.t_LF2start = 0.0
self.t_LF3start = 0.0
self.LFRT_TRIP = False
def debug_simulation(self,t):
""" Print to terminal for debugging."""
utility_functions.print_to_terminal('t:{:.4f}'.format(t))
if self.DEBUG_VOLTAGES:
utility_functions.print_to_terminal('Vdc_ref:{:.3f},Vdc:{:.3f},Vat:{:.3f},Va:{:.3f},Vag:{:.3f},Vagrid:{:.3f},Vagrid_setpoint:{:.3f}'. format(self.PV_model.Vdc_ref,self.PV_model.Vdc,self.PV_model.Vtrms,self.PV_model.Vrms,self.grid_model.Vgrms,abs(self.grid_model.Vagrid_no_conversion)/math.sqrt(2),abs(self.grid_model.Vagrid)/math.sqrt(2)))
if self.DEBUG_CURRENTS:
utility_functions.print_to_terminal('ia_ref:{:.3f},ia:{:.3f},iload1:{:.3f}'. format(self.PV_model.ia_ref,self.PV_model.ia,self.PV_model.iaload1))
if self.DEBUG_POWER:
utility_functions.print_to_terminal('Sinsol:{:.3f},Q_ref:{:.3f},Ppv:{:.3f},S:{:.3f},S_PCC:{:.3f},S_load1:{:.3f},S_G:{:.3f}'.format(self.PV_model.Sinsol,self.PV_model.Q_ref,self.PV_model.Ppv,self.PV_model.S,self.PV_model.S_PCC,self.PV_model.S_load1,self.PV_model.S_G))
if self.DEBUG_CONTROLLERS:
utility_functions.print_to_terminal('xDC:{:.3f},xQ:{:.3f},ua:{:.3f},xa:{:.3f},ma:{:.3f}'. format(self.PV_model.xdc,self.PV_model.xQ,self.PV_model.ua,self.PV_model.xa,self.PV_model.ma))
if self.DEBUG_PLL:
utility_functions.print_to_terminal("we:{:.3f}, wte:{:.3f} rad, vd: {:.3f} V, vq {:.3f} V".format(self.PV_model.we,self.PV_model.wte,self.PV_model.vd,self.PV_model.vq))