A power system comprising: a series string comprising a first group coupled in series to a second group; wherein the first group comprises a first plurality of power sources (501a-m) that are serially connected, wherein the second group comprises a plurality of power devices (509n-z) that are serially connected, and each of the plurality of power devices is connected to a respective power source of a second plurality of power sources (501n-z), and wherein each of the plurality of power devices (509n-z) comprises: a first terminal, a second terminal, a third terminal, and a fourth terminal, wherein the first terminal and the second terminal are coupled to the respective power source of the second plurality of power sources (501n-z), the third terminal and the fourth terminal couple the power device to the series string, and the first terminal is directly connected to the fourth terminal; a first switch coupled between the second terminal and the third terminal; a diode coupled between the third terminal and the fourth terminal, wherein the diode comprises an anode and a cathode, and the anode is connected to the third terminal and the cathode is connected to the fourth terminal; a controller configured to operate the power device in multiple modes to prevent the series string voltage from rising above a maximum allowable limit, wherein: (i) in a first mode, the controller is configured to disconnect the respective power source of the second plurality of power sources by controlling the first switch to be in the OFF state to disconnect the second terminal from the third terminal, (ii) in a second mode, the controller is configured to connect the respective power source of the second plurality of power sources by controlling the first switch to be in the ON state to connect the second terminal to the third terminal. a series string comprising a first group coupled in series to a second group; wherein the first group comprises a first plurality of power sources (501a-m) that are serially connected, wherein the second group comprises a plurality of power devices (509n-z) that are serially connected, and each of the plurality of power devices is connected to a respective power source of a second plurality of power sources (501n-z), and wherein each of the plurality of power devices (509n-z) comprises: a first terminal, a second terminal, a third terminal, and a fourth terminal, a first terminal, a second terminal, a third terminal, and a fourth terminal, wherein the first terminal and the second terminal are coupled to the respective power source of the second plurality of power sources (501n-z), the third terminal and the fourth terminal couple the power device to the series string, and the first terminal is directly connected to the fourth terminal; a first switch coupled between the second terminal and the third terminal; a diode coupled between the third terminal and the fourth terminal, wherein the diode comprises an anode and a cathode, and the anode is connected to the third terminal and the cathode is connected to the fourth terminal; a controller configured to operate the power device in multiple modes to prevent the series string voltage from rising above a maximum allowable limit, wherein: (i) in a first mode, the controller is configured to disconnect the respective power source of the second plurality of power sources by controlling the first switch to be in the OFF state to disconnect the second terminal from the third terminal, (ii) in a second mode, the controller is configured to connect the respective power source of the second plurality of power sources by controlling the first switch to be in the ON state to connect the second terminal to the third terminal. a first switch coupled between the second terminal and the third terminal; a diode coupled between the third terminal and the fourth terminal, wherein the diode comprises an anode and a cathode, and the anode is connected to the third terminal and the cathode is connected to the fourth terminal; a controller configured to operate the power device in multiple modes to prevent the series string voltage from rising above a maximum allowable limit, wherein: (i) in a first mode, the controller is configured to disconnect the respective power source of the second plurality of power sources by controlling the first switch to be in the OFF state to disconnect the second terminal from the third terminal, (ii) in a second mode, the controller is configured to connect the respective power source of the second plurality of power sources by controlling the first switch to be in the ON state to connect the second terminal to the third terminal. (i) in a first mode, the controller is configured to disconnect the respective power source of the second plurality of power sources by controlling the first switch to be in the OFF state to disconnect the second terminal from the third terminal, (ii) in a second mode, the controller is configured to connect the respective power source of the second plurality of power sources by controlling the first switch to be in the ON state to connect the second terminal to the third terminal.