Patent ID: 9444258
Filing Date: 2016-09-13
CPC Classification: H02J,Y02E

Claim Text:
1. A photovoltaic system, comprising: a controller including a power-increment (PI) module to be used to determine whether a specific conductance derivative ratio enters a threshold tracking zone, and an incremental-conductance (INC) module to be used to operate the controller when the specific conductance derivative ratio enters the threshold tracking zone; a photovoltaic current (Ipv); a photovoltaic voltage (Vpv); and a photovoltaic power (Ppv), wherein the PI module includes a Ppv-Vpv curve, the INC module includes an Ipv-Vpv curve, the controller is guided by the Ppv-Vpv curve and the Ipv-Vpv curve such that the photovoltaic system is engaged in a maximum power point tracking (MPPT), when the specific conductance derivative ratio on the Ipv-Vpv curve is located in the threshold tracking zone having a minimum value larger than a first conductance derivative ratio and a maximum value smaller than a second conductance derivative ratio, the controller uses the Ipv-Vpv curve to engage in an INC fine tracking, when the specific conductance derivative ratio is located outside the threshold tracking zone, the controller uses the Ppv-Vpv curve to engage in a PI coarse tracking, and when the first conductance derivative ratio is ρ where Vpv is an output voltage of the PV array, Ipv is an output current of the PV array, ΔIpv is a change of the Ipv, and ΔVpv is a change of the Vpv.