DC concentrated-distributed power distribution system for municipal roads

Abstract

The invention discloses a DC concentrated-distributed power distribution system for municipal roads. The system comprises an AC isolation transformer, the output end of a secondary coil of the AC isolation transformer is connected with an AC 0..4kV bus via a first intelligent protection switch, the wire output end of the AC 0..4kV bus is connected with a common DC bus via a second intelligent protection switch, a three-phase four-quadrant PWM controllable rectifier and a third intelligent protection switch, the output end of the common DC bus is connected with a close-range power supply loop and a long-distance power supply loop, the close-range power supply loop is composed of an isolated DC-DC converter and parallel LED street lamp terminals, and the long-distance power supply loop is composed of a DC voltage regulation power distribution cabinet and LED street lamp terminals arranged in the wire output end of the DC voltage regulation power distribution cabinet in parallel. The system has the advantage that traditional illumination power distribution stations for municipal roads can be reduced greatly, one power distribution station (a power supply area unit) of the system can over 9 traditional illumination power distribution stations, and the economic returns are high.

Description

technical field [0001] The invention relates to municipal road systems, in particular to a direct current centralized-distributed power distribution system for municipal roads. Background technique [0002] At present, there are mainly two types of DC power distribution systems for municipal roads: one is AC power supply, and each terminal load is equipped with an AC-DC power module. The built-in AC-DC power supply module in the LED lamp supplies power to the LED street lamp through step-down, filtering, rectification, and voltage regulation. The other type is powered by a low-voltage AC distribution box, adding a set of DC power boxes, changing the original AC trunk line to a DC trunk line, and configuring a DC-DC voltage regulating module at each load terminal; this mode is filtered by a low-voltage power supply, three Phase bridge thyristor rectifier (generally adjustable output voltage DC180V-DC300V), laid to the light pole via DC power supply cable, and then powered by...

AI Technical Summary

Problems solved by technology

[0003] For the former mode, it is actually still an AC power supply mode, and each LED lamp of the terminal load needs to be equipped with an AC-DC power module to drive the LED light source; its functions are EMC, rectification and filtering, power drive, inverter step-down Voltage, voltage and current stabilization, and power factor correction, etc., make the control circuit of LED lamps complex, with many components and high cost; and the service life of the AC-DC power module is largely limited by the use of electrolytic capacitors in the power module. life

[0004] For the latter mode, although the DC power supply mode is adopted, the power supply structure mode is extremely unreasonable: This is mainly: 1. Simply adding a DC power supply panel to each low-voltage AC distribution box does not give full play to the advantages of the DC power system , both AC power points and DC power points are added, resulting in serious waste of resources; 2. Due to the scattered layout of AC-DC power screens, it is not conducive to comprehensive harmonic control, which increases a lot of costs for the expansion of future microgrid technology ; 3. Due to the increase of AC-DC equipment, the number of electrical failure points increases, and the reliability of power supply is poor; 4. The rectifier power box cannot be inverted, and the energy cannot be fed back to the AC grid. It is used for the development of ubiquitous power grid limit

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