A renewable energy-based hybrid bi-directionally interactive DC traction power supply system

Patent metadata

Field	Value
Publication number	US-2016159250-A1
Application number	US-201414907808-A
Country	US
Kind code	A1
Filing date	Jul 26, 2014
Priority date	Jul 29, 2013
Publication date	Jun 9, 2016
Grant date	—

Abstract

A renewable energy-based hybrid bi-directionally interactive DC traction power supply system includes two traction substations. Each substation includes transformers, rectifiers, bidirectional AC-DC converters, a DC bus, a catenary, a steel rail and a section post. A DC bus between two adjacent traction substations is provided with a DC renewable energy system constructed by an electric vehicle charging-discharging system, a distributed generation and more than one low voltage DC microgrid. The DC renewable energy system is connected to the DC bus between two adjacent traction substations through a high voltage DC bus, thus a DC circular microgrid being formed in a power supply section post. The electric vehicle charging-discharging system is formed by more than one bidirectional DC-DC charging-discharging equipments which are intended for in connection with the power batteries of the electric vehicle. The renewable energy-based hybrid bi-directionally interactive DC traction power supply system of the invention realizes effective usage of distributed generation and recycling of electric locomotive braking energy, reducing DC voltage fluctuation, thus improving reliability of the DC traction power supply system.

First claim

What is claimed is:

1 . A renewable energy-based hybrid bi-directionally interactive DC traction power supply system comprising at least two traction substations ( 1 ) for supplying DC energy to an electric locomotive ( 2 ), wherein each traction substation ( 1 ) has more than one first transformer ( 11 ) connected to a AC bus ( 5 ) and more than one second transformer ( 17 ) connected to the AC bus ( 5 ); the other end of each first transformer ( 11 ) is correspondingly coupled to a rectifier ( 12 ), and the other end of each second transformer ( 17 ) is correspondingly coupled to a bidirectional AC-DC converter ( 18 ); the other end of each rectifier ( 12 ) and bidirectional AC-DC converter ( 18 ) is coupled to a DC bus ( 13 ) of a corresponding traction substation ( 1 ); the positive and negative ends of the DC bus ( 13 ) are connected to a catenary ( 14 ) and steel rail ( 15 ) respectively; the positive and negative ends of the electric locomotive ( 2 ) are connected to the catenary ( 14 ) and steel rail ( 15 ) respectively; the catenary ( 14 ) of each traction substation ( 1 ) is coupled with a section post 16 ; the both ends of the section post 16 are connected to positive end of a corresponding DC bus ( 13 ); a DC bus ( 13 ) between two adjacent traction substations ( 1 ) is provided with a DC renewable energy system ( 3 ) constructed by an electric vehicle charging-discharging system, a distributed generation and more than one low voltage DC microgrid ( 31 ); the DC renewable energy system ( 3 ) is connected to the DC bus ( 13 ) between two adjacent traction substations ( 1 ) through a high voltage DC bus ( 4 ), thus a DC circular microgrid being formed in a power supply section post, and wherein the electric vehicle charging-discharging system is formed by more than one bidirectional DC-DC charging-discharging equipments ( 32 ) which are intended for in connection with the power batteries of the electric vehicle.

2 . The renewable energy-based hybrid bi-directionally interactive DC traction power supply system as recited in claim 1 , wherein an output end, for connecting to the power batteries of the electric vehicle, of each DC-DC charging-discharging equipments ( 32 ) is connected in parallel to a super capacitor.

3 . The renewable energy-based hybrid bi-directionally interactive DC traction power supply system as recited in claim 1 , wherein the distributed generation includes more than one micro gas turbine ( 33 ), more than one wind turbine generator 35 , more than one fuel cell ( 37 ), and more than one solar photovoltaic cell ( 39 ); each of the micro gas turbine ( 33 ) and wind turbine generator 35 is connected respectively to the high voltage DC bus ( 4 ) by a unidirectional AC-DC converter ( 34 / 36 ); and each of the fuel cell ( 37 ) and solar photovoltaic cell ( 39 ) is connected respectively to the high voltage DC bus ( 4 ) by a unidirectional DC-DC converter ( 38 / 40 ).

4 . The renewable energy-based hybrid bi-directionally interactive DC traction power supply system as recited in claim 1 , wherein the low voltage DC microgrid ( 31 ) comprises a circular low voltage DC bus ( 311 a ) connected to the high voltage DC bus ( 4 ) via a bidirectional DC-DC converter ( 312 ), more than one energy storage device ( 3110 ), more than one micro gas turbine ( 316 ), more than one solar photovoltaic cell ( 317 ), more than one fuel cell ( 318 ), more than one wind turbine generator ( 319 ), more than one unidirectional DC-AC converter ( 3111 ), more than one bidirectional DC-DC charging-discharging equipment ( 3112 ), and more than one unidirectional DC-DC converter ( 3113 ); each of the solar photovoltaic cell ( 317 ) and fuel cell ( 318 ) is connected respectively to the circular low voltage DC bus ( 311 a ) by a unidirectional DC-DC converter ( 3117 / 3116 ); each of the micro gas turbine ( 316 ) and wind turbine generator ( 319 ) is connected respectively to the circular low voltage DC bus ( 311 a ) by a unidirectional AC-DC converter ( 3114 / 3115 ); each energy storage device ( 3110 ) is connected to the circular low voltage DC bus ( 311 a ) through a bidirectional DC-DC converter ( 3118 ); an output end of each unidirectional DC-AC converter ( 3111 ) is connected to an AC load ( 313 ); the other end of each bidirectional DC-DC charging-discharging equipment ( 3112 ) is connected to the battery of the electric vehicle ( 314 ); and an output end of each unidirectional DC-DC converter ( 3113 ) is connected to a DC load ( 315 ).

5 . The renewable energy-based hybrid bi-directionally interactive DC traction power supply system as recited in claim 1 , wherein the low voltage DC microgrid ( 31 ) comprises a radial low voltage DC bus ( 311 b ) connected to the high voltage DC bus ( 4 ) via a bidirectional DC-DC converter ( 312 ), more than one energy storage device ( 3110 ), more than one micro gas turbine ( 316 ), more than one solar photovoltaic cell ( 317 ), more than one fuel cell ( 318 ), more than one wind turbine generator ( 319 ), more than one unidirectional DC-AC converter ( 3111 ), more than one bidirectional DC-DC charging-discharging equipment ( 3112 ), and more than one unidirectional DC-DC converter ( 3113 ); each of the solar photovoltaic cell ( 317 ) and fuel cell ( 318 ) is connected respectively to the radial low voltage DC bus ( 311 b ) by a unidirectional DC-DC converter ( 3117 / 3116 ); each of the micro gas turbine ( 316 ) and wind turbine generator ( 319 ) is connected respectively to the radial low voltage DC bus 311 b by a unidirectional AC-DC converter ( 3114 / 3115 ); each energy storage device ( 3110 ) is connected to the radial low voltage DC bus ( 311 b ) through a bidirectional DC-DC converter ( 3118 ); an output end of each unidirectional DC-AC converter ( 3111 ) is connected to an AC load ( 313 ); the other end of each bidirectional DC-DC charging-discharging equipment ( 3112 ) is connected to the battery of the electric vehicle ( 314 ); and an output end of each unidirectional DC-DC converter ( 3113 ) is connected to a DC load ( 315 ).

6 . A renewable energy-based hybrid bi-directionally interactive DC traction power supply system comprising a traction substations ( 1 ) for supplying DC energy to an electric locomotive ( 2 ), wherein each traction substation ( 1 ) has more than one first transformer ( 11 ) connected to a AC bus ( 5 ) and more than one second transformer ( 17 ) connected to the AC bus ( 5 ); the other end of each first transformer ( 11 ) is correspondingly coupled to a rectifier ( 12 ), and the other end of each second transformer ( 17 ) is correspondingly coupled to a bidirectional AC-DC converter ( 18 ); the other end of each rectifier ( 12 ) and bidirectional AC-DC converter ( 18 ) is coupled to a DC bus ( 13 ) of a corresponding traction substation ( 1 ); the positive and negative ends of the DC bus ( 13 ) are connected to a catenary ( 14 ) and steel rail ( 15 ) respectively; the positive and negative ends of the electric locomotive ( 2 ) are connected to the catenary ( 14 ) and steel rail ( 15 ) respectively; a DC bus ( 13 ) is provided with a DC renewable energy system ( 3 ) constructed by an electric vehicle charging-discharging system, a distributed generation and more than one low voltage DC microgrid ( 31 ); the DC renewable energy system ( 3 ) is connected to the DC bus ( 13 ) of the traction substations ( 1 ) through a high voltage DC bus ( 4 ), thus a DC circular microgrid being formed in a power supply section post, and wherein the electric vehicle charging-discharging system is formed by more than one bidirectional DC-DC charging-discharging equipments ( 32 ) which are intended for in connection with the power batteries of the electric vehicle.

7 . The renewable energy-based hybrid bi-directionally in

Assignees

• State Grid Corp China
• Univ North China Elec Power
• State Grid Liaoning Electric Power Company Ltd Economic Res Inst

Inventors

• Meng Ming
• Liu Jian
• Wang Xiping
• Hu Dalong
• Jiang Li
• Song Yingwei
• Liu Yan
• Ning Liaoyi

Classifications

• B60M1/307

  Supports · CPC title

• B60M3/06 Primary

  Arrangements for consuming regenerative power · CPC title