A modular interconnection device , comprising: a modular port assembly configured to transmit alternating current (AC) and/or direct current (DC); a node (N0) coupled to an AC source via a first switch and the modular port assembly , the first switch being configured to selectively disconnect the modular interconnection device from the AC source; a converter coupled to the node (N0) via a second switch and coupled to a DC source via a third switch , the converter configured to convert the AC current into DC current or convert DC current into AC current; characterized in that the modular interconnection device further comprises a local controller coupled to the first, second and third switches and configured to control operation of the first, second and third switches, wherein the modular port assembly comprises: a first port coupled to the first switch and configured to receive the AC current from the AC source or transmit AC current to the AC source; a second port coupled to the node (N0) directly or via a fourth switch , and configured to selectively transmit the AC current between modular interconnection devices; a third port coupled to the third switch and configured to selectively transmit the DC current between the modular interconnection devices; and a fourth port coupled to the node (N0) and configured to transmit the AC current between the modular interconnection devices. a modular port assembly configured to transmit alternating current (AC) and/or direct current (DC); a node (N0) coupled to an AC source via a first switch and the modular port assembly , the first switch being configured to selectively disconnect the modular interconnection device from the AC source; a converter coupled to the node (N0) via a second switch and coupled to a DC source via a third switch , the converter configured to convert the AC current into DC current or convert DC current into AC current; characterized in that the modular interconnection device further comprises a local controller coupled to the first, second and third switches and configured to control operation of the first, second and third switches, wherein the modular port assembly comprises: a first port coupled to the first switch and configured to receive the AC current from the AC source or transmit AC current to the AC source; a second port coupled to the node (N0) directly or via a fourth switch , and configured to selectively transmit the AC current between modular interconnection devices; a third port coupled to the third switch and configured to selectively transmit the DC current between the modular interconnection devices; and a fourth port coupled to the node (N0) and configured to transmit the AC current between the modular interconnection devices. a first port coupled to the first switch and configured to receive the AC current from the AC source or transmit AC current to the AC source; a second port coupled to the node (N0) directly or via a fourth switch , and configured to selectively transmit the AC current between modular interconnection devices; a third port coupled to the third switch and configured to selectively transmit the DC current between the modular interconnection devices; and a fourth port coupled to the node (N0) and configured to transmit the AC current between the modular interconnection devices. <EOS>