BorgWarner sequential charging technology enables fleets to pair up to 5 dispensers with a single power control system (PCS) cabinet. This configuration streamlines the Direct Current Fast Charger (DCFC) installation and infrastructure process.
With a three-dispenser sequential charging configuration, the vehicle in position one charges until it reaches 90% (state of charge) SOC, or for the duration of one hour (whichever happens first). The other 2 dispensers are off and on idle. After the vehicle in position 1 charges to the designated level, the DCFC charger in position 2 activates to charge to the desired SOC, and the process repeats. The process continues until all vehicles are charged to the desired level. Sequential charging priorities can be configured both locally &/or via the cloud.
Sequential charging paired with predictable idle times provides an ideal solution to ensure zero-emission transportation during the day without impacting the regular operation of the route.
This technology is well-suited for fleets with defined duty cycles, depots, and downtime. Some examples of fleets that can take advantage of sequential charging include:
Multiple high-power DCFC infrastructure installations require considerable trenching, electrical panel upgrades, and potential transformer upgrades. However, BorgWarner’s sequential charging reduces the switch gear connection by up to a factor of 5. Additionally, the BorgWarner sequential approach uses a daisy chain interconnection between power cabinet and between the dispensers, eliminating the need for additional conduits from the power conversion system (PCS) also known as "power cabinet" to a central junction box required for hub-and-spoke DCFC configurations.
BorgWarner utilized only one breaker for each PCS. In comparison, installing five 24kW lower power DC 100 Amp breakers, versus the BorgWarner 60kW solution that only needs one 100 Amp breaker. In addition, BorgWarner DC Fast chargers charge 3 to 6 faster than AC Level 2 systems during priority charging events.
Several public funding opportunities are available for sequential DCFC technology from the federal, state, and local governments. We recently partnered with the School District of the City of Pontiac in Michigan to maximize the EPA’s per-port funding using sequential charging – creating a clear roadmap for success with installing electric bus charging infrastructure.