Inverter

inverter – converts direct current (DC) (e.g. from solar panels or batteries) to alternating current (AC).

Synopsis
module generators; class inverter { enumeration {FOUR_QUADRANT=4, PWM=3, TWELVE_PULSE=2, SIX_PULSE=1, TWO_PULSE=0} inverter_type; enumeration {NONE=0,CONSTANT_PQ=1,CONSTANT_PF=2, VOLT_VAR=4, LOAD_FOLLOWING=5, GROUP_LOAD_FOLLOWING=6} four_quadrant_control_mode; enumeration {INCLUDED,EXCLUDED} pf_reg enumeration {ONLINE=2, OFFLINE=1} generator_status; enumeration {SUPPLY_DRIVEN=5, CONSTANT_PF=4, CONSTANT_PQ=2, CONSTANT_V=1, UNKNOWN=0} generator_mode; complex V_In [ V ] ; complex I_In [ A ] ; complex VA_In [ VA ] ; complex VA_Out [ VA ] complex Vdc [ V ] ; complex phaseA_V_Out [ V ] ; complex phaseB_V_Out [ V ] ; complex phaseC_V_Out [ V ] ; complex phaseA_I_Out [ A ] ; complex phaseB_I_Out [ A ] ; complex phaseC_I_Out [ A ] ; complex power_A [ VA ] ; complex power_B [ VA ] ; complex power_C [ VA ] ; complex P_Out [ VA ] ; complex Q_Out [ VAr ] ; complex power_factor [ unit ] ; double power_in [ W ] ; double rated_power [ VA ] ; double rated_battery_power [ W ] ; double inverter_efficiency; double battery_soc [ pu ] ; double soc_reserve [ pu ] ; bool use_multipoint_efficiency; enumeration {XANTREX=3, SMA=2, FRONIUS=1, NONE=0} inverter_manufacturer; double maximum_dc_power [ W ] ; double maximum_dc_voltage [ V ] ; double minimum_dc_power [ W ] ; double c_o [ 1/W ] ; double c_1 [ 1/V ] ; double c_2 [ 1/V ] ; double c_3 [ 1/V ] ; set {S=112, N=8, C=4, B=2, A=1} phases; object sense_object; double max_charge_rate [ W ] ; double max_discharge_rate [ W ] ; double charge_on_threshold [ W ] ; double charge_off_threshold [ W ] ; double discharge_on_threshold [ W ] ; double discharge_off_threshold [ W ] ; double excess_input_power [ W ] ; double charge_lockout_time [ s ] ; double discharge_lockout_time [ s ] ; double pf_reg_activate; double pf_reg_deactivate; double pf_reg_activate_lockout_time [ s ] ; double charge_threshold [ W ] ; double discharge_threshold [ W ] ; double group_max_charge_rate [ W ] ; double group_max_discharge_rate [ W ] ; double group_rated_power [ W ] ; double V_base [ V ] ; double V1 [ pu ] ; double V2 [ pu ] ; double V3 [ pu ] ; double V4 [ pu ] ; double Q1 [ pu ] ; double Q2 [ pu ] ; double Q3 [ pu ] ; double Q4 [ pu ] ; }

Default Inverter
The minimum definition for an inverter is

object inverter { generator_mode CONSTANT_PF; << implied child that provides a DC power input >> }

Example
module generators; object inverter { generator_mode CONSTANT_PF; generator_status ONLINE; inverter_type PWM; power_factor 1.0; parent triplex_meter2; << implied child that provides a DC power input >> }

Volt/Var Control Mode
The VOLT_VAR mode is used to have the inverter generate/absorb VARs based off of the system voltage seen at the inverter terminals. The output on each phase determined on the system voltage measured on said phase. for example, in a three phase inverter, the output on phase A is based off of the phase A voltage measurement, the output on phase B is based off of the phase B voltage measurement, and the output on phase C is based off of the phase C voltage measurement. The inverter determines how much VARs are generated or absorbed by a volt/VAR curve that the user creates by setting the V1, V2, V3, V4, Q1, Q2, Q3, and Q4 parameters. See the illustration below showing curve generated by these parameters.



The values of these parameters is per unit. V_base is used to convert the voltage measurement to a per unit value. The rated_power parameter is used to convert the per unit value of VAR output into VARs. Note that rated_power is a per-phase limit, so for three-phase inverters, the overall limit will be three-times that value. The inverter will try to output the amount of VARs determined from the curve without exceeding the power curve of the inverter.

object inverter { name volt_var_inv; parent inv_meter; inverter_type FOUR_QUADRANT; four_quadrant_control_mode VOLT_VAR; generator_status ONLINE; generator_mode SUPPLY_DRIVEN; phases ABC; rated_power 70 kVA;// per phase; inverter_efficiency 0.87; //Volt Var parameters; V_base 7200; V1 0.90; Q1 0.7; V2 0.95; Q2 0.0; V3 1.05; Q3 0.0; V4 1.10; Q4 -0.8; }