Institute of Transportation, MOTC

       In order to provide better and faster transit service, priority signal control strategies should be implemented; however, the discussions on conditional priority signal control strategies are still insufficient in Taiwan. This study presents a conditional priority signal control logic for public transport systems, especially for Bus Rapid Transit (BRT) and Light Rail Transit (LRT).
       Kaohsiung Light Rail Transit System (Phase 1) adopts a full priority signal control strategies, in which green time is extended or red time is truncated to give LRT vehicle full priority. The full priority signal policy can greatly improve the travel time of the light rail, but it also destroys the traffic signal coordination. As far as the overall road network is concerned, traffic system performance is highly
deteriorated.
       This study proposes a signal control logic for conditional priority for transit vehicles. Signal control policies and possible strategies, including green time extension, red time truncation, new phase, and skip phase, are evaluated based on transit vehicle arrival times and overall traffic system performance.