How EV OS Load Management Works

What's the Purpose of Load Management

Load management, or load balancing, optimizes power distribution among charging stations at a site. It prevents electrical overload, optimizes charging speeds, and maximizes the use of available power. Our advanced power management algorithms ensure the safety and smooth operation of stations by efficiently managing the available power supply. 

How Load Management Works

Load Management dynamically adjusts power distribution at charging sites by continuously monitoring each station’s status to ensure the current stays within a specified range. The system intelligently allocates available capacity to ensure efficient usage.

Consider a charging site with 3 stations and a total site capacity of 36 A, each with a minimum output of 7 A and a maximum output of 32 A.

When only two stations are occupied, each station provides a maximum charge of 18 A.

As more vehicles arrive, the software evenly distributes the available current for maximum efficiency. When a third vehicle is plugged in, the current is evenly distributed to 12 A per vehicle.

Minimum / Maximum Output

The maximum output of a station is determined by the station model, as specified in the EV OS database. The minimum output value, on the other hand, is pre-defined in EV OS, considering local regulations. See the chart below for detailed information.

A station will not start charging if the remaining load is less than its minimum output.

What Happens When a Station Goes Offline?

If a station goes offline due to internet issues or other unforeseen reasons, EV OS assumes it operates at its rated (maximum) output as a safety measure. Until the station is restored, it will continue to occupy this rated current.

Consider a charging site with five stations and a total capacity of 63 A. Four of the five stations are occupied. Each station has a minimum output of 7 A and a maximum output of 32 A.

If one of the occupied stations goes offline, the following occurs:

1. The offline station stops supplying current to the vehicle. The system reserves 32 A for the offline station, leaving 31 A to be shared among the remaining three stations. (63 A site limit – 32A reserved for offline station = 31 A available.)
2. The available output will first be distributed evenly across the remaining vehicles. (31 A / 3 = 10 A each with 1 A surplus)
3. Any surplus amperage will then be allocated sequentially among the vehicles. (The first station receives 11 A)

What If Multiple Stations Go Offline?

When multiple stations go offline, the system would attempt to reserve the max. output from the offline stations while reducing the output of occupied online stations to the minimum.

See the example below:

Assuming four cars are charging, with a fifth car incoming. If two stations go offline under the same site configuration (32 A max. output, 7 A min. output), the following occurs:

1. The system attempts to reserve 64 A from offline stations but is constrained by the site capacity of 63 A.
2. The system then lowers the current supply to the occupied online stations, using the minimum output, which is 7 A in this case.
3. The fifth vehicle cannot be charged because the site’s capacity has been fully allocated.

For more information about how to configure Load Management, download our manual from the link below.