DRIVE CONTROL DEVICE OF HYBRID VEHICLE

• US 20140081500A1
• Filed: 02/21/2011
• Published: 03/20/2014
• Est. Priority Date: 02/21/2011
• Status: Active Grant

• Current Assignee: Suzuki Motor Corporation
• Original Assignee: Suzuki Motor Corporation
• Inventors: Ito, Yoshiki, Tagawa, Masaaki, Saito, Masakazu, Ohkuma, Hitoshi, Hosoe, Yukihiro
• Granted Patent: US 9,026,293 B2
• Time in Patent Office: Days
• US Class Current: 701/22
• CPC Class Codes: B60K 6/365 with the gears having orbital motion
• CPC Class Codes: B60K 6/445 Differential gearing distribution type
• CPC Class Codes: B60L 15/02 characterised by the form of the current used in the control circuit
• CPC Class Codes: B60L 2240/545 Temperature
• CPC Class Codes: B60L 50/61 by batteries charged by engine-driven generators, e.g. series hybrid electric vehicles
• CPC Class Codes: B60L 58/13 Maintaining the SoC within a determined range
• CPC Class Codes: B60L 58/15 Preventing overcharging
• 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 20/10 Controlling the power contribution of each of the prime movers to meet required power demand
• 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 2520/10 Longitudinal speed
• CPC Class Codes: B60W 2540/10 Accelerator pedal position
• CPC Class Codes: B60W 30/1882 characterised by the working point of the engine, e.g. by using engine output chart
• CPC Class Codes: Y02T 10/40 Engine management systems
• 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 10/84 : Data processing systems or methods, management, administration
• CPC Class Codes: Y02T 10/92 : Energy efficient charging or discharging systems for batteries, ultracapacitors, supercapacitors or double-layer capacitors specially adapted for vehicles
• CPC Class Codes: Y10S 903/93 : Conjoint control of different elements

Abstract

Objects of the present invention is to improve the control accuracy of the charge state of a battery in consideration of the electric power losses of a plurality of motor generators and, in accordance therewith, to secure the protection performance of the battery, and to increase the energy recovery efficiency according to the regeneration. According to the present invention, there is provided a drive control device of a hybrid vehicle in which an electric power loss predicting means and a target electric power calculating means are arranged, a target engine power calculating means calculates target engine power based on target driving power, target charge/discharge power, and estimated power that is an electric power loss, and a motor torque instruction value calculating means calculates torque instruction values of a plurality of motor generators using a torque balance equation including target engine torque and an electric power balance equation including the target electric power. In the electric power balance equation, electric power generated or consumed by the plurality of motor generators, the estimated power that is the electric power loss, and input/output electric power of the battery are included.

Claims

1. A drive control device of a hybrid vehicle comprising:

an internal combustion engine that includes an output shaft;

a driving shaft that is connected to a drive wheel;

first and second motor generators;

a differential gear mechanism that includes four rotating components connected to a plurality of the motor generators, the driving shaft, and the internal combustion engine;

an accelerator opening degree detecting means that detects the accelerator opening degree;

a vehicle speed detecting means that detects a vehicle speed;

a battery charge state detecting means that detects a charge state of a battery;

a target driving power setting means that sets target driving power based on the accelerator opening degree that is detected by the accelerator opening degree detecting means and the vehicle speed detected by the vehicle speed detecting means;

a target charge/discharge power setting means that sets target charge/discharge power based on at least the charge state of the battery that is detected by the battery charge state detecting means;

a target engine power calculating means that calculates target engine power based on the target driving power of the target driving power setting means and the target charge/discharge power of the target charge/discharge power setting means;

a target engine operating point setting means that sets a target engine operating point based on the target engine power and total system efficiency;

a motor torque instruction value calculating means that calculates target rotation speeds of the plurality of the motor generators and sets torque instruction values of the motor generators;

an electric power loss predicting means that calculates estimated power that is an electric power loss based on the target rotation speeds and the torque instruction values of the plurality of the motor generators; and

a target electric power calculating means that calculates target electric power based on a difference between the target engine power calculated by the target engine power calculating means and the target driving power,

wherein the target engine power calculating means calculates the target engine power based on the target driving power, the target charge/discharge power, and the estimated power that is the electric power loss,

wherein the motor torque instruction value calculating means calculates torque instruction values of the plurality of motor generators using a torque balance equation including target engine torque acquired at the target engine operating point and an electric power balance equation including the target electric power, and

wherein electric power generated or consumed by the plurality of the motor generators, the estimated power that is the electric power loss in the plurality of motor generators, and input/output electric power of the battery are included in the electric power balance equation.

2. The drive control device of the hybrid vehicle according to claim 1, wherein the electric power loss predicting means calculates the estimated power that is the electric power loss of the first motor generator using a quadratic polynomial having the target rotation speed (previous value) and the torque instruction value (previous value) of the first motor generator as variables, and calculates the estimated power that is the electric power loss of the second motor generator using a quadratic polynomial having the target rotation speed (previous value) and the torque instruction value (previous value) of the second motor generator as variables.

3. The drive control device of the hybrid vehicle according to claim 1, further comprising a power upper limit/lower limit value calculating means that sets an upper limit value of the electric power and a lower limit value of the electric power limiting input/output electric power of the battery based on the battery state parameters,

wherein the target electric power calculating means calculates the target electric power based on a difference between the target engine power calculated by the target engine power calculating means and the target driving power and limits the target electric power to the upper limit value of the electric power or the lower limit value of the electric power when the target electric power comes off a range set by the upper limit value of the electric power and the lower limit value of the electric power.

4. The drive control device of the hybrid vehicle according to claim 3, wherein the power upper limit/lower limit value calculating means determines the upper limit value of the electric power or the lower limit value of the electric power by subtracting the estimated power from a retrieved value acquired through a search from a search table based on the temperature, the voltage, and the charge state as the battery state parameters.