Hybrid energy locomotive system and method

Claim 2

A diesel-electric locomotive system comprising: a locomotive having an engine; a power converter driven by the engine providing primary electric power; a traction bus coupled to the power converter and carrying the primary electric power; a first inverter drive coupled to the traction bus and receiving the primary electric power; a first traction motor coupled to the first inverter drive, said first traction motor having a dynamic braking mode of operation and a motoring mode of operation, said first traction motor generating dynamic braking electrical power which is returned to the traction bus when operating in the dynamic braking mode, said first traction motor propelling the locomotive in response to the primary electric power when operating in the motoring mode; a second inverter drive coupled to the traction bus and receiving the primary electric power; a second traction motor coupled to the second inverter drive; and a hybrid energy system, said hybrid energy system comprising: an energy storage device providing secondary electric power; a transfer switch electrically connected between the second inverter drive and the second traction motor and electrically connected to the energy storage device, said transfer switch having first and second mutually exclusive connection states, said first connection state connecting the second inverter drive to the second traction motor and said second connection state connecting the energy storage device to the second inverter drive; and a switch controller controlling the connection state of the transfer switch, wherein when the first traction motor is in the dynamic braking mode of operation and the switch controller places the transfer switch in the second connection state, the first inverter drive provides dynamic braking electrical power generated by the first traction motor to the traction bus and the second inverter drive receives from the traction bus a portion of the dynamic braking electrical power and transfers the portion of the dynamic braking electrical power to the energy storage device for storage, such that the secondary electric power is derived from the portion of the dynamic braking electrical power stored in the energy storage device.

Claim 3

The system of claim 1 wherein the second inverter drive is operable for transferring power to the traction bus and wherein when the first traction motor is in the motoring mode of operation and the switch controller places the transfer switch in the second connection state, the energy storage device supplies the secondary electric power to the second inverter drive, whereby the second inverter drive transfers the secondary electric power to the traction bus such that first traction motor propels the locomotive in response to the secondary electric power and the primary electric power.

Claim 4

The system of claim 1 wherein when the first traction motor is in the motoring mode of operation and the switch controller places the transfer switch in the first connection state, the second inverter drive transfers a portion of the primary electric power to the second traction motor such that the second traction motor operates in a motoring mode of operation to assist the first traction motor in propelling the locomotive.

Claim 5

The system of claim 1 wherein when the first traction motor is in the motoring mode of operation and the switch controller places the transfer switch in the second connection state, the second inverter drive transfers a portion of the primary electric power to the energy storage device, said energy storage device storing the transferred portion of the primary electric power whereby the secondary electric power is derived from the portion of the primary electric power stored in the energy storage device.

Claim 6

The system of claim 1 further comprising a charging source selectively connected to the traction bus, said charging source providing charging electric power carried on the traction bus, wherein when the charging source is connected to the traction bus and the switch controller places the transfer switch in the second connection state, the second inverter drive transfers a portion of the charging electric power to the energy storage device, said energy storage device storing the transferred portion of the charging electric power whereby the secondary electric power is derived from the portion of the charging electric power stored in the energy storage device.

Claim 7

The system of claim 1 wherein the energy storage device comprises a battery.

Claim 10

The system of claim 7 wherein the energy storage device comprises three batteries, a first one of the three batteries being connected to a first one of the three output phases, a second one of the three batteries being connected to a second one of the three output phases, and a third one of the three batteries being connected to a third one of the three output phases.

Claim 11

The system of claim 7 wherein the energy storage device comprises a first battery and a second battery, said first battery being connected to a first one and a second one of the three output phases, and said second battery being connected to a third one of the three output phases.

Claim 12

The system of claim 1 wherein the energy storage device comprises a flywheel system.

Claim 13

The system of claim 10 wherein the energy storage device further comprises at least two output phases and a battery, said battery being connected to a first one of the at least two output phases and said flywheel system being connected to a second one of the at least two output phases.

Claim 14

The system of claim 1 wherein the energy storage device comprises: at least two phases; a first storage component being connected to a first one of the at least two phases, said first storage component storing a first portion of the dynamic braking electrical power; a second storage component being connected to a second one of the at least two phases; and wherein the second inverter drive selectively transfers a part of the first portion of the dynamic braking electrical power stored in the first storage component to the second storage component.

Claim 15

The system of claim 1 wherein the energy storage device comprises an ultracapacitor.

Claim 16

A retrofit system for modifying a diesel-electric locomotive system to operate as a hybrid energy locomotive system, said diesel-electric locomotive system including a locomotive having an engine, a power converter driven by the engine providing primary electric power, a traction bus coupled to the power converter and carrying the primary electric power, a first inverter drive coupled to the traction bus and receiving the primary electric power, a first traction motor coupled to the first inverter drive, said first traction motor having a dynamic braking mode of operation and a motoring mode of operation, said first traction motor generating dynamic braking electrical power which is returned to the traction bus when operating in the dynamic braking mode, said first traction motor propelling the locomotive in response to the primary electric power when operating in the motoring mode, the diesel-electric locomotive system also including a second inverter drive coupled to the traction bus and receiving the primary electric power, and a second traction motor coupled to the second inverter drive, the retrofit system comprising: an energy storage device providing secondary electric power; a transfer switch electrically connected between the second inverter drive and the second traction motor and electrically connected to the energy storage device, said transfer switch having first and second mutually exclusive connection states, said first connection state connecting the second inverter drive to the second traction motor and said second connection state connecting the energy storage device to the second inverter drive; and a switch controller controlling the connection state of the transfer switch, wherein when the first traction motor is in the dynamic braking mode of operation and the switch controller places the transfer switch in the second connection state, the first inverter drive provides dynamic braking electrical power generated by the first traction motor to the traction bus and the second inverter drive receives from the traction bus a portion of the dynamic braking electrical power and transfers the portion of the dynamic braking electrical power to the energy storage device for storage such that the secondary electric power is derived from the portion of the dynamic braking electrical power stored in the energy storage device.

Claim 17

A retrofit system for modifying a diesel-electric locomotive system to operate as a hybrid energy locomotive system, said diesel-electric locomotive system including a locomotive having an engine, a power converter driven by the engine providing primary electric power, a traction bus coupled to the power converter and carrying the primary electric power, a first inverter drive coupled to the traction bus and receiving the primary electric power, a first traction motor coupled to the first inverter drive, said first traction motor having a dynamic braking mode of operation and a motoring mode of operation, said first traction motor generating dynamic braking electrical power which is returned to the traction bus when operating in the dynamic braking mode, said first traction motor propelling the locomotive in response to the primary electric power when operating in the motoring mode, the diesel-electric locomotive system also including a second inverter drive coupled to the traction bus and receiving the primary electric power, and a second traction motor coupled to the second inverter drive, the retrofit system comprising: an energy storage device providing secondary electric power; a transfer switch electrically connected between the second inverter drive and the second traction motor and electrically connected to the energy storage device, said transfer switch having first and second mutually exclusive connection states, said first connection state connecting the second inverter drive to the second traction motor and said second connection state connecting the energy storage device to the second inverter drive; and a switch controller controlling the connection state of the transfer switch, wherein when the first traction motor is in the dynamic braking mode of operation and the switch controller places the transfer switch in the second connection state, the first inverter drive provides dynamic braking electrical power generated by the first traction motor to the traction bus and the second inverter drive receives from the traction bus a portion of the dynamic braking electrical power and transfers the portion of the dynamic braking electrical power to the energy storage device for storage such that the secondary electric power is derived from the portion of the dynamic braking electrical power stored in the energy storage device.

Claim 18

The retrofit system of claim 14 wherein the second inverter drive is operable for transferring power to the traction bus and wherein when the first traction motor is in the motoring mode of operation and the switch controller places the transfer switch in the second connection state, the energy storage device supplies the secondary electric power to the second inverter drive, whereby the second inverter drive transfers the secondary electric power to the traction bus such that first traction motor propels the locomotive in response to the secondary electric power and the primary electric power.

Claim 19

The retrofit system of claim 14 wherein when the first traction motor is in the motoring mode of operation and the switch controller places the transfer switch in the first connection state, the second inverter drive transfers a portion of the primary electric power to the second traction motor such that the second traction motor operates in a motoring mode of operation to assist the first traction motor in propelling the locomotive.

Claim 20

The retrofit system of claim 14 wherein when the first traction motor is in the motoring mode of operation and the switch controller places the transfer switch in the second connection state, the second inverter drive transfers a portion of the primary electric power to the energy storage device, said energy storage device storing the transferred portion of the primary electric power whereby the secondary electric power is derived from the portion of the primary electric power stored in the energy storage device.

Claim 21

The retrofit system of claim 14 further comprising a charging source selectively connected to the traction bus, said charging source providing charging electric power carried on the traction bus, wherein when the charging source is connected to the traction bus and the switch controller places the transfer switch in the second connection state, the second inverter drive transfers a portion of the charging electric power to the energy storage device, said energy storage device storing the transferred portion of the charging electric power whereby the secondary electric power is derived from the portion of the charging electric power stored in the energy storage device.

Claim 22

The retrofit system of claim 14 wherein the energy storage device comprises a battery.

Claim 23

The retrofit system of 14 wherein the transfer switch comprises a three phase transfer switch and wherein the energy storage device includes three output phases, said transfer switch being constructed and arranged to selectively connect at least one of the three output phases of the energy storage device to the second inverter drive.

Claim 24

The retrofit system of 14 wherein the transfer switch comprises a three phase transfer switch and wherein the energy storage device includes three output phases, said transfer switch being constructed and arranged to selectively connect at least one of the three output phases of the energy storage device to the second inverter drive.

Claim 25

The retrofit system of claim 20 wherein the energy storage device comprises three batteries, a first one of the three batteries being connected to a first one of the three output phases, a second one of the three batteries being connected to a second one of the three output phases, and a third one of the three batteries being connected to a third one of the three output phases.

Claim 26

The retrofit system of claim 20 wherein the energy storage device comprises a first battery and a second battery, said first battery being connected to a first one and a second one of the three output phases, and said second battery being connected to a third one of the three output phases.

Claim 27

The retrofit system of claim 14 wherein the energy storage device comprises a flywheel system.

Claim 28

The retrofit system of claim 23 wherein the energy storage device further comprises at least two output phases and a battery, said battery being connected to a first one of the at least two output phases and said flywheel system being connected to a second one of the at least two output phases.

Claim 29

The retrofit system of claim 14 wherein the energy storage device comprises: at least two phases; a first storage component being connected to a first one of the at least two phases, said first storage component storing a first portion of the dynamic braking electrical power; a second storage component connected to a second one of the at least two phases; and wherein the second inverter drive selectively transfers a part of the first portion of the dynamic braking electrical power stored in the first storage component to the second storage component.

Claim 30

The retrofit system of claim 14 wherein the energy storage device comprises an ultracapacitor.

Claim 33

The method of claim 27 wherein the second inverter drive is operable for transferring the secondary electric power from the energy storage device to the traction bus, wherein controlling the state of the transfer switch further comprises: placing the transfer switch in the second connection state when the first traction motor is in the motoring mode of operation such that the second inverter drive selectively transfers the secondary electric power from the energy storage device to the traction bus.

Claim 34

The method of claim 28 further comprising controlling the transfer of secondary electric power from the energy storage device to the traction bus by operating the second inverter drive as a chopper.

Claim 35

The method of claim 27 wherein the first and second connection states are mutually exclusive, and wherein controlling the state of the transfer switch further comprises: placing the transfer switch in the first connection state when the second traction motor is needed to assist the first traction motor in the dynamic braking mode of operation.

Claim 36

The method of claim 27 wherein the first and second connection states are mutually exclusive, and wherein controlling the state of the transfer switch further comprises: placing the transfer switch in the first connection state when the second traction motor is needed to assist the first traction motor in the motoring mode of operation.

Claim 37

The method of claim 27 wherein the transfer switch comprises a three phase switch and wherein the energy storage device includes three output phases, and wherein controlling the state of the transfer switch further comprises: connecting at least one of the three output phases of the energy storage device to the second inverter drive when the transfer switch is in the second connection state.

Claim 38

The method of claim 32 wherein the energy storage device comprises three batteries, the method further comprising: connecting a first one of the three batteries being connected to a first one of the three output phases; connecting a second one of the three batteries being connected to a second one of the three output phases; and connecting a third one of the three batteries being connected to a third one of the three output phases.

Claim 39

The method of claim 32 wherein the energy storage device comprises a first battery and a second battery, the method further comprising: connecting the first battery to a first one of the three output phases; connecting the first battery to a second one of the three output phases; and connecting the second battery to a third one of the three output phases.

Claim 40

The method of claim 27 wherein the energy storage device comprises a flywheel system and wherein installing the energy storage device on the locomotive comprises installing the flywheel system.

Claim 41

The method of claim 35 wherein the energy storage device further comprises at least two output phases, and wherein installing the energy storage device on the locomotive further comprises connecting the battery to a first one of the at least two output phases and connecting the flywheel system to a second one of the at least two output phases.

Claim 42

The method of claim 27 wherein installing a transfer switch further comprises electrically connecting the transfer switch between the second inverter drive and the second traction motor and installing the energy storage device comprises electrically connecting the energy storage device to the transfer switch.

Claim 43

The method of claim 27 when the transfer switch is in the second connection state, further comprising: providing dynamic braking electrical power generated by the first traction motor to the traction bus from the first inverter drive; receiving a portion of the dynamic braking electrical power at the second inverter drive from the traction bus; and transferring the portion of the dynamic braking electrical power from the second inverter drive to the energy storage device for storage.