By the early to mid 2000s, the physical limitations of semi-conductor based, microelectronics had begun to alter the course of processor design. Clock speeds, which had increased by several orders of magnitude in the latter part of the 20th century, could no longer be significantly enhanced. As a result, manufacturers began to focus more on parallel computing via multi-core processors in order to increase computing power. Since then, 12, 16 and even higher-core processors have since become more prominent in newer personal computers.
Beginning in the late 2000s, requests for PSCAD and EMTDC to take advantage of parallel computing techniques began to rise. In response to this increasing feedback, the development direction began to move in part towards the exploitation of multiple-core processors; this in order to increase simulation efficiency and reduce the time needed to extract results. Versions prior to v4.5 (released in 2012) did not utilize more than two processor cores. PSCAD and EMTDC ran on separate cores, but there was always only one EMTDC process running at any given time.
With the release of v4.5, two unique parallel computing functions were incorporated that both utilize multiple processor cores: A parallel solution of transmission lines and cables, and a rudimentary ability to launch multiple EMTDC simulation runs simultaneously, where each EMTDC runtime process is based on a unique case project. In v4.6, the ability to launch multiple EMTDC processes from a single project was introduced. Initially called Volley Launch, an enhanced version of it, called Parallel Multiple Run (PMR) was included in v5.0. Also added in v4.6, multiple case projects representing multiple parts of a complete electric network, can be run simultaneously as a single simulation, connected via transmission line or cable interfaces. This feature is referred to as the Parallel Network Interface (PNI).
NOTE: A standard PSCAD license allows a maximum of eight simultaneous, parallel EMTDC simulations. For information on increasing this limit (maximum 1,024) , contact the PSCAD Sales Desk (sales@pscad.com).