HYBRID WORKING MACHINE

• US 20100102763A1
• Filed: 10/19/2009
• Published: 04/29/2010
• Est. Priority Date: 10/29/2008
• Status: Active Grant

• Current Assignee: Kobelco Construction Machinery Company Limited (Kobe Steel Limited)
• Original Assignee: Kobelco Construction Machinery Company Limited (Kobe Steel Limited)
• Inventors: KAGOSHIMA, Masayuki, KOMIYAMA, Masayuki, SHIMOMURA, Keisuke
• Granted Patent: US 8,286,740 B2
• Time in Patent Office: Days
• US Class Current: 318/380
• CPC Class Codes: B60K 6/46 Series type
• CPC Class Codes: B60L 1/003 to auxiliary motors, e.g. for pumps, compressors
• CPC Class Codes: B60L 1/20 Energy regeneration from auxiliary equipment
• CPC Class Codes: B60L 2200/40 Working vehicles
• CPC Class Codes: B60L 50/61 by batteries charged by engine-driven generators, e.g. series hybrid electric vehicles
• CPC Class Codes: B60L 7/02 Dynamic electric resistor braking B60L7/22 takes precedence
• CPC Class Codes: B60L 7/10 Dynamic electric regenerative braking B60L7/22 takes precedence
• CPC Class Codes: B60W 10/04 including control of propulsion units
• CPC Class Codes: B60W 10/06 including control of combustion engines
• CPC Class Codes: B60W 10/08 including control of electric propulsion units, e.g. motors or generators
• CPC Class Codes: B60W 10/26 for electrical energy, e.g. batteries or capacitors
• CPC Class Codes: B60W 20/00 Control systems specially adapted for hybrid vehicles hybrid vehicle design, B60K6/00; electric vehicles B60L
• CPC Class Codes: B60W 20/50 Control strategies for responding to system failures, e.g. for fault diagnosis, failsafe operation or limp mode
• CPC Class Codes: B60W 2050/0297 Control Giving priority to different actuators or systems
• CPC Class Codes: B60W 2300/17 Construction vehicles, e.g. graders, excavators
• CPC Class Codes: B60W 2510/244 Charge state
• CPC Class Codes: B60Y 2200/412 Excavators
• CPC Class Codes: E02F 9/123 Drives or control devices specially adapted therefor E02F9/125 and E02F9/128 take precedence
• CPC Class Codes: E02F 9/2075 of the hybrid type for vehicles in general B60W20/00
• CPC Class Codes: E02F 9/2091 Control of energy storage means for electrical energy, e.g. battery or capacitors energy recovery arrangements in hydraulic or pneumatic drives E02F9/2217
• CPC Class Codes: Y02T 10/62 : Hybrid vehicles
• CPC Class Codes: Y02T 10/70 : Energy storage systems for electromobility, e.g. batteries
• CPC Class Codes: Y02T 10/7072 : Electromobility specific charging systems or methods for batteries, ultracapacitors, supercapacitors or double-layer capacitors

Abstract

In a hybrid excavator, a generator motor and a hydraulic pump are driven by using an engine as a power source. A battery is charged with power generated by the generator motor. A rotation motor is driven by the generator motor and the battery. The voltage of a DC bus is detected by a voltage sensor, and whether the battery is unusable is determined by a breakdown detector. When the battery becomes unusable, emergency evacuation control is performed so that the power consumption of the rotation motor will be suppressed to be less than or equal to the power generation of the generator motor while maintaining the DC bus voltage greater than or equal to the normal operation voltage of the system.

Claims

1. A hybrid working machine comprising:

an engine serving as a power source;

a hydraulic pump serving as a hydraulic power source of a hydraulic actuator, the hydraulic pump being driven by the engine;

a generator driven by the engine;

an electric storage device that is charged with electric power generated by the generator;

a rotation motor serving as a driving source of a rotating structure, the rotation motor being driven by the generator and the electric storage device;

electric-storage-device breakdown detecting means for detecting that the electric storage device is unusable; and

control means for controlling the generator and the rotation motor, wherein, when it is detected by the electric-storage-device breakdown detecting means that the electric storage device is unusable, the control means is configured to perform emergency evacuation control that suppresses the power consumption of the rotation motor to be less than or equal to the power generation of the generator while maintaining voltage of a direct current bus greater than or equal to a normal operation voltage of a control system of the hybrid working machine.

2. The hybrid working machine according to claim 1, further comprising:

a regenerative resistor that consumes regenerative power when the rotation motor is performing a regenerative operation; and

regenerative-resistor controlling means for controlling the regenerative resistor.

3. The hybrid working machine according to claim 1, further comprising bus voltage detecting means for detecting the voltage of the direct current bus,

wherein the electric-storage-device breakdown detecting means detects that the electric storage device is unusable when the bus voltage detected by the bus voltage detecting means at start-up in a state in which the electric storage device is connected to the direct current bus is less than a set value.