KR100204985B1 - Control method of diesel-electric bybrid bus system - Google Patents

Abstract

The present invention relates to a control method of a diesel-electric hybrid bus system for assisting torque by a diesel engine by driving an electric motor according to an engine speed in a diesel-electric hybrid bus system using diesel and electricity as power sources. .

The present invention includes a diesel engine (10) and an induction motor (12) as a driving source for driving a vehicle, and converts the DC power of the battery (14) to AC power so as to drive the induction motor (12). An electronic control device having an inverter 16 for converting the amount of power generated by the induction motor 12 into a direct current, controlling the operation of the inverter 16 and controlling the overall operation of the hybrid bus system. The ECU 18 is provided with an auxiliary ECU 20 which senses key input of various function switches and controls the lighting of an indicator together with information display of the vehicle status.

Description

Control Method of Diesel-Electric Hybrid Bus System

The present invention relates to a control method of a diesel-electric hybrid bus system using diesel and electricity as power sources. More particularly, the present invention relates to a diesel-electric system that assists torque by a diesel engine by driving an electric motor according to an engine speed. The present invention relates to a control method of a hybrid bus system.

Recently, as interest in the environment has increased, in-depth research has been conducted on ways to reduce the smoke of automobiles as a way to protect the environment.As a part of the research, electric vehicles using electric energy instead of fossil fuel as a main power source Attention is focused. In recent years, experimental electric vehicles have been developed in some countries, and some research results have been achieved.However, due to the characteristics of moving vehicles, electric vehicles that need to be equipped with a power battery have problems such as short driving distance, long fuel recharging time, and high price. It is not easily universalized.

In order to protect the environment and save energy, we are continuously conducting research on reducing emissions, improving safety, and improving fuel efficiency in vehicles using existing fossil fuels. A hybrid electric vehicle has been developed.

This hybrid type or hybrid type can easily solve the problem of the power battery, which is the biggest problem of the complete electric vehicle, and also has many feasibility in terms of ring protection. This solves the problem of charging, which is a low-pollution vehicle, which is an intermediate step toward the complete pollution-free vehicle.

It is divided into series type and parallel type according to the power connection method of electric motor, battery and engine. In series type, battery power is supplied by engine power and the motor is driven by rotating the motor with this power source. It can be designed separately, so the structure can be simplified, but since the generator which converts mechanical energy into electrical energy is necessary, the overall efficiency is deteriorated. On the other hand, the parallel type engine and the motor drive the vehicle simultaneously. It is designed to combine the engine and the motor in such a way that it is designed to be complicated structure and difficult to control, but in some cases using the motor as a generator to charge the battery it is possible to obtain the efficiency at high speed.

According to the present invention, the city bus is frequently stopped due to its driving characteristics and emits a lot of smoke when decelerating. Therefore, the city bus has been developed as a main culprit of atmospheric and noise pollution. In order to reduce the fuel consumption rate of practical driving by regenerating and reusing the wasted energy during braking, and to support low power by reducing the exhaust gas of diesel engine by assisting the electric motor during acceleration, the parallel hybrid vehicle as described above is used. It is an object of the present invention to provide a control method of a diesel-electric hybrid bus system that can drive a vehicle at the same time as a diesel engine and an electric motor or at the output of a diesel engine according to the driving environment.

The present invention for realizing the above object is to form a diesel engine coupled to a generator combined electric motor to control the start function, torque assistance, power generation and energy sacrifice and electric brake function according to the inverter control by the computer. .

1 is a block diagram of a hybrid bus system according to the present invention.

2 is a flow chart for explaining a start mode control method of a hybrid bus system according to the present invention.

3 is a flowchart illustrating a method for controlling an acceleration mode of a hybrid bus system according to the present invention.

4 is a flowchart illustrating a deceleration mode control method of a hybrid bus system according to the present invention.

5 is a flowchart illustrating a shift mode control method of a hybrid bus system according to the present invention.

* Explanation of symbols for main parts of the drawings

10: diesel engine 12: induction motor

14 battery 16 inverter

18: electronic control unit (ECU) 20: auxiliary ECU

22: engine pulley 24: engine speed sensor

26: resistor 28: DC / DC converter

40: information display device

Hereinafter, the configuration and operation of the present invention will be described in detail with reference to the accompanying drawings.

The hybrid bus system according to the present invention includes a diesel engine 10 and an induction motor 12 as a driving source for driving a vehicle, and converts a DC power source of the battery 14 into an AC power source to drive the induction motor 12. Inverter 16 converts the power generation amount by the induction motor 12 into direct current, and controls the operation of the inverter 16 and controls the overall operation of the hybrid bus system. An electronic control unit (ECU) 18 is provided, and an auxiliary ECU 20 for detecting key input of various function switches and controlling the lighting of an indicator light together with information display of the vehicle status is provided. .

The starting mode according to the present invention is a step of checking whether there is an abnormality of the system when the main power supply for the operation of the electronic control unit (ECU) is turned on. Determining the position and operation status of the forced charge switch. At this time, if the gear is not in neutral or the forced charge switch is off, the system is checked again with the check lamp turned on, but the gear is in the neutral position. If the switch is off, the normal lamp is turned on and the gating for driving the induction lamp is prepared. Then, a start signal is input to determine that the ignition key is connected to the on state. To maximize the speed, at which time the engine speed is determined that the cranking When it reaches (dy) it is to reduce the torque assistance, and then start the engine is completed when the engine speed reaches the idling speed (dx) to complete the engine drive and maintain the idle rpm.

In addition, when the pressure of the accelerator pedal is detected in the state where the starting mode is completed, the reference speed set by the size of dx0dx1 dx2 dx2 dx4 is compared to determine the current rotation speed and the torque auxiliary amount. If the torque is increased in proportion to the step force and the engine speed is between dx0 and dx1 or between dx1 and dx2, the accelerator pedal and rpm are judged to be smaller than the reference depth (dp) by determining the depth of the accelerator pedal. When the torque assist amount calculated is greater than 0, the torque assist amount is set to 0, but when the calculated torque amount is less than 0, the torque amount is compared with the reference torque amount dr. When smaller than), it develops to the maximum value, and when the torque is greater than the reference torque (dr), it generates as much as the calculated torque. If the depth of is deeper than the very deep reference depth (dp) but smaller than the larger reference depth (dp) or the rotation speed is larger than dx2, the torque is determined by the accelerator pedal. If it is determined that it is larger than the reference depth (dq), the step of determining whether the engine speed is smaller than dx3 is performed. If it is determined to be smaller than the auxiliary torque as calculated by the accelerator pedal and rpm as described above, if it is greater than dx4 is made to perform the acceleration mode to zero the torque assist.

However, when the pressure of the brake pedal is detected during the acceleration mode, if it is determined that the torque calculated by the engine speed is greater than a certain reference torque (a), the torque auxiliary amount is zero, and it is not greater than the reference torque (a). If it is determined that the reference torque (b) is larger than that, it generates power at the maximum torque value, and if it is determined that the reference torque (b) is larger than the reference torque (b), it is configured to perform the deceleration mode to perform the torque assist as much as the torque calculated by the engine speed. .

On the other hand, if the operation of the clutch pedal is not detected after starting the engine, torque assist operation is performed according to the engine speed.However, if the clutch pedal pressure is detected, the engine speed is compared with the reference speed (dx2) set in the acceleration mode. If it is determined that it is smaller than that, it is determined whether it is in the torque assist state, and if it is in the torque assist state, the auxiliary amount according to the engine speed is multiplied by the reference size (J). If the engine speed is determined to be greater than the reference speed (dx2), multiply the auxiliary amount by the reference size (I) and, if not in the torque assist state, perform the shifting mode to multiply the auxiliary amount by the reference size (P). will be.

1 is a block diagram of a hybrid bus system according to the present invention.

Here, the diesel engine 10 is the same as a conventional diesel engine, and is configured to assist the torque of the diesel engine 10 by controlling the rotation of the induction motor 12, and by the diesel engine 10. When assisting the torque is made to assist the torque by rotating the rotational speed of the induction motor 12 faster than the engine rotational speed. To this end, a plurality of count gears are attached to the engine pulley 22 to allow the ECU 18 to detect the engine speed through the speed detection sensor 24.

On the other hand, the inverter 16 has a resistor that serves to consume the energy flowing in to charge the capacitor when the voltage is higher than the upper limit voltage when charging the battery 14 and at the same time consumes the energy flowing in the retarder operation ( 26, and a DC / DC converter 28 for reducing the output voltage of the battery 14 and the floating motor 12 so as to be used as a power source for the electrical equipment.

The gear neutral signal, the retarder signal, the clutch signal, the brake signal, the start signal, and the acceleration signal are input to the input port of the ECU 18, and the auxiliary shock ECU 20 is connected to another input port of the ECU 18. The buzzer stop switch 30 and the forced charge switch 32, the gating off switch 34, the reset switch 36 and the auxiliary ECU switch 38 are connected to the input port of the auxiliary ECU 20, and the output port Digital information display device 40, normal lamp 42, inspection lamp 44, stop lamp 46, earth leakage lamp 48, charging lamp 50, motor temperature lamp 52 and brake temperature lamp ( 54) are connected.

Wherein the digital information display device 40 is to display the current state of the battery, such as battery voltage, current, torque assist amount to inform the driver, the buzzer stop switch 30 is artificial when various lamps are turned on or the buzzer sounds And a reset switch 36 and an auxiliary ECU reset switch 38 are switches configured to reset the ECU 18 and the auxiliary ECU 20 in the driver's seat, respectively.

And the normal lamp 42 is to inform the driver when the current system is normal, the check lamp 44 is to inform the driver when there is an error in any part of the current system, the stop lamp 46 is the current system In this abnormal case, the ECU 18 turns on when an error continuously occurs even after retrying several times. In addition, the ground fault lamp 48 is turned on when a ground fault occurs in the current system, the charging lamp 50 is a switch that is turned on when the battery 14 is currently being charged.

2 is a flowchart illustrating a start mode control method of a hybrid vehicle system according to the present invention.

First, when the main power is supplied to the ECU 18 that controls the overall operation of the hybrid bus system, the ECU 18 turns on the inspection lamp 44 during the inspection while checking the system, and when the inspection is completed, the normal lamp 42 ) Flashes.

At this time, if the ignition key is connected in the on state, it is determined whether the gear is in the neutral position and whether the forced charging switch is turned off. Thus, if the gear is not in the neutral position or the forced charge switch is not turned off, the system check operation is performed by turning on the check lamp 44 again, and if the forced charge switch is turned off while the gear is in the neutral position, the normal lamp ( 42) lights up to inform the driver that the current system is normal and prepare for gating for driving the induction motor (12).

Subsequently, when a start signal is inputted by the driver's start key, gating starts and cranks. At this time, the torque assist amount of the diesel engine 10 by the induction motor 12 is maximized.

In this way, when the engine speed reaches the rotation speed (dy) which can be determined that the cranking is completed, the start is completed while reducing the torque assistance until the idle speed (dx) is reached, the idle speed (dx ), Complete the engine and keep the idle rpm.

3 is a flowchart illustrating a method of controlling an acceleration mode of a hybrid bus system according to the present invention.

As described in FIG. 2, when the pressure of the accelerator pedal is detected in the state where the starting mode is completed, the ECU 18 detects the engine speed in order to determine the torque assistance amount, and then sets the preset reference speed dx0, dx1, dx2, dx2, and dx4).

Here, the reference speeds dx0, dx1, dx2, dx2, dx4 are set to the same size as dx0dx1dx2dx2dx4, and the engine speed is divided into six stages as an example, and the torque assistance amount by the induction motor 12 is changed according to the engine speed. Although it is set to control, the rotation speed difference between each step may be divided equally, but it is preferable to divide it differently as desired for efficient control.

When the driver operates the accelerator pedal in the idling state and the acceleration signal is input to the ECU 18, the ECU 18 detects the engine speed through the rotation speed sensor 24.

At this time, if the detected rotation speed is less than or equal to dx0, the torque is increased in proportion to the pedal effort of the accelerator pedal to control the starting torque of the diesel engine 10 at the start, and the engine speed is between dx0 and dx1 or between dx1 and dx2. In this case, the step of determining the depth of the accelerator pedal is performed. This is to eliminate the torque caused by the induction motor 12 and to increase the thermal efficiency and to reduce the power consumption of the battery by controlling the driving of the vehicle by the torque by the diesel engine 10 when the vehicle speed increases to some extent after the start. However, in addition to the basic control operation, it is to determine the pedaling depth of the accelerator pedal, which is to assist the torque of the diesel engine 10 to the induction motor 12 when the accelerator pedal is pressed very deeply.

To this end, if it is determined that the accelerator pedal depth is smaller than the reference depth (dp), it is determined whether the torque assist amount calculated by the accelerator pedal and rpm is greater than 0. If the accelerator pedal amount is greater than 0, the torque assist amount is set to 0, but the calculated torque amount is 0. If smaller, the torque amount is compared with the reference torque amount dr. Then, the torque amount is developed to the maximum value when the torque amount is smaller than the reference torque amount dr, and the calculated torque amount when the torque amount is larger than the reference torque amount dr. In the above process, if the accelerator pedal is deeper than the deep reference depth (dp) but smaller than the larger reference depth (dp) or the rotation speed is larger than dx2, the torque is determined by the accelerator pedal. consist of.

Here, the accelerator pedal depths dp and dq are set to the size of dpdq, and dq represents a state in which the accelerator pedal is relatively stepped on.

If it is determined that the accelerator pedal depth is greater than the reference depth dp, the engine pedal speed is determined to be smaller than dx3. If the engine pedal speed is smaller, the torque calculated by the accelerator pedal and the rpm is assisted. If it is determined that it is larger than dx4 compared to dx4, if it is judged to be assisted by the torque calculated by the accelerator pedal and rpm as described above, if it is determined to be larger than dx4, the torque assistance is made to zero.

4 is a flowchart illustrating a deceleration mode control method of a hybrid bus system according to the present invention.

When the brake pedal is operated and the brake signal is input to the ECU 18 during the acceleration mode, the ECU 18 compares the torque calculated by the engine speed and the reference torque (set to abc), respectively. When the determined torque is determined to be larger than the reference torque (a), the torque auxiliary amount is zero, and when determined to be smaller than the reference torque (a) but smaller than the reference torque (b), power generation is performed at the maximum torque value, and the reference torque If it is determined to be greater than (b) it is made to perform the deceleration mode to the torque assist by the torque calculated by the engine speed. When a large braking force is required by the operation of the brake pedal, the power generation amount is increased by regenerative braking of the induction motor 12 to assist the braking force.

5 is a flowchart illustrating a shift mode control method of a hybrid bus system according to the present invention.

When the clutch pedal is operated by the driver and the clutch signal is input, the ECU 18 performs a step of comparing the engine speed with the reference speed dx2 set in the acceleration mode, and if it is determined to be smaller than that, is in the torque assist state. If the torque is in the auxiliary state, multiply the auxiliary amount according to the engine speed by the reference size (J) .If the torque is not in the auxiliary state, multiply the auxiliary amount by the reference size (K), and the engine speed is greater than the reference speed (dx2). If it is determined that the auxiliary amount is multiplied by the reference size (I) while the torque assist state is to perform a shift mode to multiply the auxiliary amount by the reference size (P).

As described above, the present invention can reduce the generation of pollutants through the regeneration of electric drive and braking energy in the existing diesel engine, increase the acceleration and deceleration capacity, and reduce fuel.

Claims (4)

In the control method of a hybrid bus system equipped with a diesel engine and a motor, a step of checking whether there is a problem with the system when the main power supply for operation of the electronic control unit (ECU) is turned on, and when the inspection is completed, the normal lamp flashes and then starts. If the key is operated in the ON state, judging whether the gear is in the neutral position and the operation state of the forced charge switch.In this case, if the gear is not in the neutral position or the forced charge switch is not turned off, the system is checked again while the inspection lamp is turned on. However, if the gear is in the neutral position and the forced charging switch is off, the lamp is turned on and the gating is prepared for driving the induction motor.If the start signal is input and the start key is judged to be connected, the gating is performed. Starting with cranking to maximize torque assistance, at this time When the total speed reaches the speed (dy) which is judged to be cranking, reducing the torque assist, and then starting the engine when the engine speed reaches the idle speed (dx), the engine is completed and the idle rpm Control method of a diesel-electric hybrid bus system consisting of a starting mode to maintain the. According to claim 1, When the pressure of the accelerator pedal is detected in the state that the start mode is completed, the engine speed is less than dx0 by comparing the reference speed set to the size of dx0dx1dx2dx2dx4 to determine the current rotation speed and the torque auxiliary amount In this case, the torque is increased in proportion to the pedal force of the accelerator pedal, and if the engine speed is between dx0 and dx1 or between dx1 and dx2, the depth of the accelerator pedal is judged to be smaller than the reference depth (dp). If the torque assist amount calculated by the accelerator pedal and rpm is greater than 0, set the torque assist amount to 0, but if the calculated torque amount is less than 0, perform the step of comparing the torque amount with the reference torque amount dr. When the torque is smaller than the reference torque (dr), it is developed to the maximum value, and when the torque is greater than the torque (dr), it is generated by the calculated torque. If the accelerator pedal is deeper than the deep reference depth (dp) but smaller than the larger reference depth (dq) or the rotation speed is greater than dx2, the torque is determined by the accelerator pedal. If it is determined that the engine speed is smaller than dx3 in the judgment step, the engine speed is smaller than dx3. If it is smaller, it is assisted by the torque calculated by the accelerator pedal and rpm. In comparison, if it is determined to be smaller than dx4, the control method of the diesel-electric hybrid bus system is configured to perform the acceleration mode to assist with the torque calculated by the accelerator pedal and rpm as described above and to set the torque assist to zero if it is determined to be larger than dx4. . According to claim 2, If the pressure of the brake pedal is detected during the acceleration mode, if it is determined that the torque calculated by the engine speed is greater than a certain reference torque (a), the torque assist amount is zero, the reference When it is determined that it is larger than the torque (a) but smaller than the reference torque (b), it generates power at the maximum torque value, and when it is determined that it is larger than the reference torque (b), it is a deceleration to perform torque assist by the torque calculated by the engine speed. Control method of a diesel-electric hybrid bus system configured to perform a mode. According to claim 1, If the operation of the clutch pedal is not detected when the starting mode is completed, the torque assist operation is performed according to the engine speed, while if the pressure of the clutch pedal is detected, the engine speed was set in the acceleration mode If it is determined that it is smaller than that by performing the step of comparing with the reference speed (dx2), it is determined whether it is in the torque assist state, and if it is in the torque assist state, the auxiliary amount according to the engine speed is multiplied by the reference size (J). If the engine speed is judged to be greater than the reference speed (dx2), multiply the assistance by the reference size (I), and multiply the assistance by the reference size (P) if it is not torque assisted. A control method of a diesel-electric hybrid bus system configured to perform a shift mode to make a shift mode.

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