CONTROL DEVICE FOR CONTROLLING CONVERTER

• US 20150258900A1
• Filed: 03/11/2015
• Published: 09/17/2015
• Est. Priority Date: 03/12/2014
• Status: Active Grant

• Current Assignee: DENSO Corporation
• Original Assignee: DENSO Corporation
• Inventors: MORII, Akiyoshi
• Granted Patent: US 9,623,862 B2
• Time in Patent Office: Days
• US Class Current: 1/1
• CPC Class Codes: B60K 6/445 Differential gearing distribution type
• CPC Class Codes: B60L 15/007 Physical arrangements or structures of drive train converters specially adapted for the propulsion motors of electric vehicles
• CPC Class Codes: B60L 15/20 for control of the vehicle or its driving motor to achieve a desired performance, e.g. speed, torque, programmed variation of speed
• CPC Class Codes: B60L 15/2009 for braking
• CPC Class Codes: B60L 2210/10 DC to DC converters
• CPC Class Codes: B60L 2210/40 DC to AC converters
• CPC Class Codes: B60L 2240/12 Speed
• CPC Class Codes: B60L 2240/36 Temperature of vehicle components or parts
• CPC Class Codes: B60L 2240/421 Speed
• CPC Class Codes: B60L 2240/423 Torque
• CPC Class Codes: B60L 2240/441 Speed
• CPC Class Codes: B60L 2240/443 Torque
• CPC Class Codes: B60L 2240/545 Temperature
• CPC Class Codes: B60L 2240/547 Voltage
• CPC Class Codes: B60L 2240/549 Current
• CPC Class Codes: B60L 2260/44 by parameter estimation
• CPC Class Codes: B60L 2270/12 of exhaust
• CPC Class Codes: B60L 3/0046 relating to electric energy storage systems, e.g. batteries or capacitors
• CPC Class Codes: B60L 3/04 Cutting off the power supply under fault conditions protective devices and circuit arrangements in general H01H; H02H
• 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: B60L 58/14 : Preventing excessive discharging
• CPC Class Codes: B60L 58/15 : Preventing overcharging
• CPC Class Codes: B60L 58/16 : responding to battery ageing, e.g. to the number of charging cycles or the state of health [SoH]
• CPC Class Codes: B60L 7/14 : for vehicles propelled by ac motors
• 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 20/14 : in conjunction with braking regeneration
• CPC Class Codes: F02N 11/04 : the motors being associated with current generators
• CPC Class Codes: F02N 11/0862 : characterised by the electrical power supply means, e.g. battery
• CPC Class Codes: F02N 2011/0896 : Inverters for electric machines, e.g. starter-generators
• CPC Class Codes: Y02T 10/62 : Hybrid vehicles
• CPC Class Codes: Y02T 10/64 : Electric machine technologies in electromobility
• 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
• CPC Class Codes: Y02T 10/72 : Electric energy management in electromobility

Abstract

In a control device, a control unit controls at least one switching element of a converter to increase a voltage supplied from a battery, thus outputting the increased voltage to a rotating electrical machine. The rotating electrical machine is capable of driving, based on the increased voltage output from the converter, an internal combustion engine, and capable of charging the battery based on torque supplied from the internal combustion engine. A limit unit limits, based on a change of an available maximum output of the internal, combustion engine, the increased voltage output from the converter to be equal to or lower than a predetermined upper limit.

Claims

1. A control device comprising:

a control unit controlling at least one switching element of a converter to increase a voltage supplied from a battery, thus outputting the increased voltage to a rotating electrical machine, the rotating electrical machine being capable of driving, based on the increased voltage output from the converter, an internal combustion engine, and capable of charging the battery based on torque supplied from the internal combustion engine; and

a limit unit limiting, based on a change of an available maximum output of the internal combustion engine, the increased voltage output from the converter to be equal to or lower than a predetermined upper limit.

2. The control device according to claim 1, wherein:

the control unit is configured to output the increased voltage to a second rotating electrical machine in addition to the rotating electrical machine, the second rotating electrical machine being capable of driving, based on the increased voltage output from the converter, an axle of a vehicle, and capable of charging the battery based on torque supplied from the axle.

3. The control device according to claim 2, wherein:

the limit unit further comprises;

a reducing unit that reduces the available maximum output of the internal combustion engine from a rated maximum output of the internal combustion engine by a predetermined level according to at least one given condition, thus obtaining a value of a first available maximum output of the internal combustion engine; and

a first calculating unit that calculates the upper limit for the increased voltage output from the converter based on the value of the first available maximum output of the internal combustion engine.

4. The control device according to claim 2, wherein:

the limit unit further comprises;

a reduction rate calculating unit that;

calculates an output reduction rate based on a ratio of an estimated torque value of the internal combustion engine to a command torque value of the internal combustion engine, the output reduction rate representing a rate of decrease of a rated maximum output of the internal combustion engine; and

multiplies the rated maximum output of the internal combustion engine by the output reduction rate, thus calculating a value of a second available maximum output of the internal combustion engine; and

a second calculating unit that calculates the upper limit for the increased voltage output from the converter based on the value of the second available maximum output of the internal combustion engine.

5. The control device according to claim 2, wherein:

the limit unit further comprises;

a reducing unit that reduces the available maximum output of the internal combustion engine from a rated maximum output of the internal combustion engine by a predetermined level, thus obtaining a value of a first available maximum output of the internal combustion engine;

a reduction rate calculating unit that;

calculates an output reduction rate based on a ratio of an estimated torque value of the internal combustion engine to a command torque value of the internal combustion engine, the output reduction rate representing a rate of reduction of a rated maximum output of the internal combustion engine per unit time; and

multiplies the rated maximum output of the internal combustion engine by the output reduction rate, thus calculating a value of a second available maximum output of the internal combustion engine;

a selecting unit that selects one of the value of the first available maximum output of the internal combustion engine and the value of the second available maximum output of the internal combustion engine; and

a calculating unit that calculates the upper limit for the increased voltage output from the converter based on the selected value of one of the first available maximum output of the internal combustion engine and the second available maximum output of the internal combustion engine.

6. The control device according to claim 5, wherein:

the selecting unit is configured to;

compare the value of the first available maximum output of the internal combustion engine with the value of the second available maximum output of the internal combustion engine; and

select, based on a result of the comparison, one of the value of the first available maximum output of the internal combustion engine and the value of the second available maximum output of the internal combustion engine, one of the value of the first available maximum output of the internal combustion engine and the value of the second available maximum output of the internal combustion engine being smaller than the other thereof.

7. The control device according to claim 3, wherein:

the reducing unit reduces the available maximum output of the internal combustion engine from the rated maximum output of the internal combustion engine by the predetermined level according to an operating condition of the internal combustion engine as the given condition.

8. A vehicle control system comprising:

a battery;

an axle;

an internal combustion engine for rotatably driving the axle;

a converter including at least one switching element;

a first rotating electrical machine;

a second rotating electrical machine;

a control unit controlling the at least one switching element of the converter to increase a voltage supplied from the battery, thus outputting the increased voltage to each of the first and second rotating electrical machines,

the first rotating electrical machine being capable of driving, based on the increased voltage output from the converter, the internal combustion engine, and capable of charging the battery based on torque supplied from the internal combustion engine,

the second rotating electrical machine being capable of driving, based on the increased voltage output from the converter, the axle, and capable of charging the battery based on torque supplied from the axle; and

a limit unit limiting, based on a change of an available maximum output of the internal combustion engine, the increased voltage output from the converter to be equal to or lower than a predetermined upper limit.