本文提出調幅與調相電流法實現併網型太陽光電發電系統之最大功率點追蹤及功因補償。文中首先利用太陽能板(或感測電池)最大功率點電壓與其開路電壓為線性關係，因此經由感測電池開路電壓之量測可完成太陽能板最大功率點電壓之決定。太陽能板實際工作電壓與最大功率點電壓比較，以電壓控制方式，針對變流器輸出電流進行調幅操作，調控太陽能板之增載或減載程序，促使系統進入最大功率點下工作。一種取得變流器輸出電流及負載電流虛部成份的方法在文中提出，之後透過變流器輸出電流與負載電流之虛部成份的比較，針對變流器輸出電流進行調相操作，此加或減調相量的改變，可促使變流器輸出電流的虛部成份完全補償負載電流虛部量，達成負載的單位功因補償。經由實作測試可確認所提之研究方法可同時實現併網型太陽光電發電系統之最大功率點追蹤及功因補償，這對系統裝置用戶而言，可在不增加系統硬體設施前提下，卻能於賣電的行為過程中獲得更多的售電收入，以及於買電的行為過程中獲得較佳的購電減價優惠，減少電費的支出。所提之最大功率點追蹤及功因補償方式，其控制方法簡單，易實現。

Current amplitude and phase modulations to implement the maximum power point tracking (MPPT) and the power factor compensation in a grid-connected PV generation system are proposed in this paper. Firstly, the linear relationship between the maximum power point (MPP) voltage and the open-circuit one in the solar panel (or in the sensing cell) is taken. Then, the MPP voltage of the solar panel is decided by the measured open-loop voltage of the sensing cell. The real-time operating voltage is compared with the decided MPP voltage on the PV panel. Taking a voltage control on the PV system, the amplitude modulation is conducted on the output current of an inverter. The system will fall into the MPP operation through a load increasing or decreasing process in the solar panel. One way taking the image parts of the inverter current and the load current is proposed in the paper. Then, comparing these image parts each other, and modulating the current phase of the inverter, the variety of a plus or a minus phase modulation can prompt a complete compensation between the image part of the inverter output current and the one of the load current. Consequently, an outcome with a unitary power factor can be produced. Through the experimental tests, it reveals that the proposed approach can achieve the maximum power point tracking (MPPT) and the power factor compensation for a grid-connected PV generation system. Without additions of hardware components, the MPPT and the power factor compensation can be simultaneously implemented for a user with an installed grid-connected PV system, and then the user will get more incomes from the sale of electric powers and can also reduce a power bill from the purchase of electric powers. The proposed approach for obtaining the MPPT and the power factor compensation is characterized by a simple control and an easy implementation.