Regenerative Braking Power Utilization Device —Supercapacitor energy storage

■ Product introduction

IN-Power's supercapacitor energy storage type regenerative braking power utilization device is based on a set of two-way DCDC converters. The regenerative braking energy will be stored in the supercapacitor when the train brakes while be released to the DC grid when the train starts; Supercapacitor is a new type of energy storage device between traditional capacitor and battery. Compared with lithium battery, it has the characteristics of large instantaneous power, and it will not set off any chemical reaction when charging with reversibility.

■ Operating principle

■ Absorption & release of brake energy

● The grid-connected state maintains a high response speed, and adjusts the supercapacitor energy storage state according to the supercapacitor power.

● It coordinates with the drooping characteristics of the traction to avoid the conflict with the traction;

● When the voltage is greater than the voltage of full-load charging threshold, the full-load charging will start to ensure the safety of the DC grid voltage.

● When the voltage is smaller than the voltage of full-load charging threshold, the full-load discharge will start to ensure the stability of the DC grid voltage.

■ Straight pressure support

When the traction station is briefly powered down, the supercapacitor can provide energy to the train so that the train can arrive safely.

Product advantage

● The whole machine adopts multi-module parallel design to improve the continuous operation capability and reliability of the equipment and facilitate the maintenance;

● Master-slave or autonomous working mode of the unit is free and flexible, suitable for a variety of working conditions;

● The unit adopts a three-level structure, with a better electromagnetic compatibility performance;

● The converter unit and the controller use optical fiber communication to greatly improve the reliability of the system.

● The switching frequency is high, the current ripple of charging and discharging of the supercapacitor is small with a long service life;

● The main control adopts FPGA+ARM architecture, and expandability of the system control scheme is strong;

● Supercapacitor cabinet adopts standard super capacitor module, which owns high overall efficiency and facilitates the expansion and transformation;

● The device is directly connected in parallel with the DC contact network for easy installation;

On-site picture of the capacitor energy storage equipment

■ System parameters

Range of operating voltage: DC450V~DC1000V (DC750V), DC1000V~DC2000V (DC1500V);

Working mode of the device: 30S/2min;

Response time: <10ms;

Efficiency of converter: >98%;

Noise: ≤75dB;

Cooling method: forced air cooling;

Communication interface: RS485 (Modbus protocol), Ethernet interface (TCP/IP protocol);

Function of multi-machine parallel: Yes;

Protection function: Over & under voltage protection of DC voltage, over-current protection, short-circuit protection, over-charge protection, over-temperature protection, over-temperature protection of converter unit, output over-voltage protection, IGBT protection, capacitor single over-voltage/over-temperature protection, frame leakage protection, emergency stop, etc.;

■ Parameters of converter unit

Rated voltage: DC1000V~DC2000V;

Rated current: -900A~+900A;

Maximum instantaneous current: -1350A~+1350A;

Rated capacity: 500kW (DC750V), 1MW (DC1500V);

■ Parameters of super capacitor

Range of operating voltage: DC300V~DC600V (DC750V), DC600V~DC1200V (DC1500V);

Voltage balance method: active or passive;