Why are energy storage trams important?

The modern tram system is an essential part of urban public transportation, and it has been developed considerably worldwide in recent years. With the advantages of safety, low cost, and friendliness to the urban landscape, energy storage trams have gradually become an important method to relieve the pressure of public transportation.

What does a battery pack do on a tram?

As the sole power source of the tram, the battery pack can supply power to the traction system and absorb the regenerative braking energy during electric braking to recharge the energy storage system. The traction system mainly consists of the inverter, traction motor, gearbox, and axle.

How to reduce the energy consumption of trams?

As tram utilization increases, the operational energy consumption of the tram system grows. Therefore, it is crucial to save energy and reduce the energy consumption of trams. One promising approach is to optimize the speed trajectory of the tram, also known as energy-efficient driving [1, 2].

Why are lithium batteries used in energy storage trams?

Compared with the traditional overhead contact grid or third-rail power supply, energy storage trams equipped with lithium batteries have been developed rapidly because of their advantages of flexible railway laying and high regenerative braking energy utilization.

Can a tram's driving strategy reduce energy consumption and extend battery life?

However, trams may face expensive battery replacement costs due to battery degradation. Therefore, this paper proposes a multi-objective optimization method for the tram's driving strategy to reduce operational energy consumption and extend battery life. The method describes the optimization problem as second-order cone programming (SOCP).

How long does a tram last?

Assuming the tram completes 12 round trips daily, and the whole life cycle is 30 years. The electricity cost, the total battery cost (including the initial acquisition cost and replacement cost), and the total cost of the whole life cycle under the two methods were calculated, respectively.