Control method for industrial vehicle and industrial vehicle

• US 20090222158A1
• Filed: 11/24/2008
• Published: 09/03/2009
• Est. Priority Date: 02/29/2008
• Status: Active Grant

• Current Assignee: Mitsubishi Nichiyu Forklift Co., Ltd. (Mitsubishi Heavy Industries, Ltd.)
• Original Assignee: Mitsubishi Heavy Industries, Ltd.
• Inventors: Kubota, Yutaka, Futahashi, Kensuke, Akaki, Tomohiro
• Granted Patent: US 8,718,843 B2
• Time in Patent Office: Days
• US Class Current: 701/22
• CPC Class Codes: B60K 1/02 comprising more than one electric motor
• CPC Class Codes: B60L 1/20 Energy regeneration from auxiliary equipment
• CPC Class Codes: B60L 2200/42 Fork lift trucks
• CPC Class Codes: B60L 2260/42 by adaptive correction
• CPC Class Codes: B60L 50/16 with provision for separate direct mechanical propulsion
• CPC Class Codes: B60L 50/61 by batteries charged by engine-driven generators, e.g. series hybrid electric vehicles
• 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 20/13 in order to stay within battery power input or output limits; in order to prevent overcharging or battery depletion
• CPC Class Codes: B60W 2510/244 Charge state
• CPC Class Codes: B60W 2710/0677 Engine power
• CPC Class Codes: B60W 2710/086 Power
• CPC Class Codes: B60Y 2200/15 Fork lift trucks, Industrial trucks
• CPC Class Codes: Y02P 90/60 Electric or hybrid propulsion means for production processes
• 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

A control method for an industrial vehicle can appropriately set a charge amount for a battery, and an industrial vehicle are provided. The control method includes an estimation step that estimates the charge rate of a battery by calculating the current that is charged to the battery and the current that is discharged from the battery; a charge amount determining step that determines the charge amount of the battery based on the estimated charge rate; a correction amount determining step that determines the charge power that is necessary for motors to generate the determined charge amount as a correction amount for the power that is supplied by the engine; and an addition step that adds the charge power to the supplied power of the engine that has been determined based on the state of the traveling and load-handling.

Claims

1. A control method for an industrial vehicle that comprises an engine that supplies power for at least traveling and load-handling, motors that supply power for at least one of said traveling and load-handling and carry out power generation, and a battery that supplies power to said motors or which is charged by the power that is generated by said motors, the control method comprising the steps of:

estimating a charge rate of said battery by quantifying a current that is charged to said battery and a current that is discharged from said battery in an estimating step;

determining a charge amount of said battery based on said estimated charge rate in a charge amount determining step;

determining a charge power that is necessary for said motors to generate said determined charge amount as a correction amount of the power that is supplied by said engine in a power correction amount determining step; and

adding said charge power to the supplied power of said engine that has been determined based on the state of said traveling and load-handling in an adding step.

4. An industrial vehicle, comprising:

an engine that supplies power for at least one of traveling and load-handling;

motors that supply power for at least one of traveling and load-handling and carry out power generation;

a battery that supplies power to said motors or is charged by the power that is generated by said motors; and

a control section that carries out the control method according to claim 1.

2. A control method for an industrial vehicle that comprises an engine that supplies power for at least traveling and load-handling, motors that supply power for at least one of said traveling and load-handling and carry out power generation, and a battery that supplies power to said motors or which is charged by the power that is generated by said motors, the control method comprising the steps of:

estimating a charge rate of said battery by quantifying a current that is charged to said battery or a current that is discharged from said battery in an estimating step; and

carrying out switching between a charging mode that prioritizes the charging of the battery and a discharging mode that prioritizes the power supply to at least one of said traveling and load-handling based on the state of said traveling and load-handling in an switching step.

3. A control method for an industrial vehicle that comprises an engine that supplies power for at least traveling and load-handling, motors that supply power for at least one of said traveling and load-handling and carry out power generation, and a battery that supplies power to said motors or which is charged by the power that is generated by said motors, the control method comprising the steps of:

estimating a charge rate of said battery by quantifying a current that is charged to said battery or a current that is discharged from said battery in an estimating step;

determining a charge amount of said battery based on said estimated charge rate in a determining step;

calculating a charge correction amount of said charge amount based on the state of said traveling and load-handling in a charge correction amount calculating step; and

adjusting said charge amount based on an operating time, which is a summed time during which either one or both of said traveling and load-handling is carried out and a summed value, which sums the charge correction amounts in an adjusting step.