DE102014203758B4 - Generator controller - Google Patents

Abstract

Generator controller with:
an excess torque section (S404) that calculates an excess torque that is producible by an internal combustion engine (2) in addition to an output torque generated by the internal combustion engine (2);
an allowance torque section (S408) that calculates an allowable torque to be assigned to a generator (4) based on the excess torque calculated by the surplus torque section (S404);
- a power generation control section (S409) that controls generation of electric power of the generator (4) such that a load torque applied to the generator (4) is within a range of the allowable torque calculated by the allowance torque section (S408); and
a load torque section (S406) that calculates the load torque applied to the generator (4) to generate electric power, wherein
- the allowable torque portion (S408) calculates the allowable torque by adding the load torque calculated by the load torque portion (S406) to the excess torque.

Description

The present invention relates to a generator controller which controls generation of electric power of a generator or an alternator.

Usually, a vehicle has an alternator (hereinafter referred to as a generator), which is driven by a driving force of an internal combustion engine to generate electric power, and a battery for charging the electric power generated by the generator. A generation amount of the generator is determined by a rotational speed of the internal combustion engine, an exciting current supplied to an exciting coil wound around a rotor, and a generating voltage which is tuned by a regulator.

Usually, when a consumption of electric power of the vehicle is high or a remaining battery capacity is small, the generator is preferably controlled so that the generation amount is increased to balance fuel efficiency and a stable power supply.

When the internal combustion engine starts, a power supply from the battery may be insufficient because the remaining battery capacity due to a stop of the engine is reduced or the power consumption is increased in accordance with a starter drive. In terms of electrical energy, the generator preferably generates the electrical energy quickly and charges the battery to increase the remaining battery capacity.

When the internal combustion engine starts to drive the generator to generate the electric power, a torque required to drive the internal combustion engine is insufficient, in accordance with a load torque required for the generator to supply the electric power produce. As a result, an increase in the rotational speed of the internal combustion engine is disturbed and a starting capability of the internal combustion engine may deteriorate.

The JP 2010 - 25 055 A discloses a technology in which, when the engine speed reaches a predetermined value determined in accordance with a temperature of a coolant, the generator starts to generate the electric power, the starting power of the engine and the generation of electric power of the engine Balancing generator.

In the JP 2010 - 25 055 A However, although the generator generates the electric power, when the rotational speed of the internal combustion engine reaches the predetermined value corresponding to a determination value of a generation start of the generator, which is set in accordance with the temperature of the coolant, the rotational speed of the internal combustion engine in accordance with an increase of the load torque decreases and, if necessary, the starting power deteriorates.

In this case, a margin can be added to the determination value by taking into consideration a decrease value of the rotation speed due to generation of electric power of the generator.

However, since the margin needs to be accurately estimated each time a part of the engine, a control method of the engine, or a control parameter of the engine is changed, the labor of estimating the margin increases.

When the generator generates the electric power during an operation of the internal combustion engine, the rotational speed is decreased in accordance with an increase in the load torque of the generator, and a change occurs in the engine operating condition.

From the DE 10 2006 000 346 A1 Further, a machine control device and an associated control method are known, wherein the engine control device includes a generator control device for controlling a generator. The DE 10 2007 017 239 A1 further describes a controller for controlling the operation of a hybrid drive. From the DE 10 2006 000 266 A1 Further, there is known a control apparatus for a vehicle generator which is driven by an engine to charge a battery and supply electric power to electric loads. The DE 198 50 581 C1 discloses a method and apparatus for determining the torque of an internal combustion engine with gasoline direct injection.

The present invention has been made in view of the above circumstances, and an object of the present invention is to provide a generator controller which ensures starting capability of an internal combustion engine, stabilizes an operating state of the internal combustion engine, and easily controls the generator to supply electric power produce.

The object is achieved by a generator controller according to claim 1. Advantageous developments are the subject of the dependent claims.

• 1 ein Blockdiagramm zur Veranschaulichung eines Energieerzeugungssteuersystems gemäß einer Ausführungsform der vorliegenden Erfindung;
• 2 eine Abbildung zur Veranschaulichung einer Softwarekonfiguration gemäß der Ausführungsform;
• 3 ein Zeitdiagramm zur Veranschaulichung einer Generatorsteuerung; und
• 4 ein Ablaufdiagramm zur Veranschaulichung eines Generatorsteuerbetriebs. (Ausführungsform)

The above and other objects, features and advantages of the present invention will become more apparent from the following detailed description made with reference to the accompanying drawings. In the drawings shows:

• 1 a block diagram illustrating a power generation control system according to an embodiment of the present invention;
• 2 an illustration for illustrating a software configuration according to the embodiment;
• 3 a timing diagram for illustrating a generator control; and
• 4 a flowchart for illustrating a generator control operation. (Embodiment)

Hereinafter, embodiments of the present invention will be described. In the embodiments, a portion corresponding to an article described in a previous embodiment may be given the same reference number and not repeatedly described. When only a portion of a configuration is described in one embodiment, another previous embodiment may be applied to the other portions of the configuration. The sections can also be combined unless explicitly described that they can be combined. The embodiments may also be partially combined, unless explicitly described, that they can be combined, provided that the combination does not entail any disadvantage.

Hereinafter, an embodiment of the present invention will be described with reference to the drawings.

1 shows a block diagram illustrating a power generation control system 10 according to the present embodiment. The power generation control system 10 controls generation of electrical energy of a generator 4 which is attached to a vehicle such as an automobile. The power generation control system 10 has a vehicle sensor 20 and an electronic control unit (ECU) 30 on. The vehicle sensor 20 has, for example, an acceleration sensor (AS) 22 , a speed sensor (SS) 24 and an intake air quantity sensor (IS) 26 on.

The ECU 30 controls a gasoline engine 2 and the generator 4 based on an output signal of the vehicle sensor 20 by executing a control program stored in a ROM. Below is the gasoline engine 2 as an internal combustion engine 2 designated.

The control program of the ECU 30 points as in 2 shown an engine control application 100 and a power generation control application 110 on. The engine control application 100 controls an operating state of the internal combustion engine 2 , and the power generation control application 110 controls a power generation state of the generator 4 by sending a command to the generator 4 sends.

The engine control application 100 controls an intake charging efficiency of the internal combustion engine 2 , an ignition timing corresponding to a combustion start timing or an air-fuel ratio such that the engine 2 generates a requested torque. That of the internal combustion engine 2 requested torque is referred to as request torque. An output torque from the internal combustion engine 2 is requested, has a request load torque generated by the generator 4 is needed to generate the electrical energy, and an accessory load torque from an accessory, such as an air conditioner on. That of the internal combustion engine 2 requested output torque is referred to as request output torque.

The engine control application 100 sends an allowable torque to the power generation control application 110 , The allowable torque describes an upper limit of a load torque that is the generator 4 is assigned to generate the electrical energy.

The power generation control application 110 controls a field current of the generator 4 and a regulator voltage of the generator 4 such that a load torque of the generator 4 is within a range of allowable torque. The control voltage is variably set based on a battery voltage and determines an upper limit of a voltage in the time in which the generator 4 generates the electrical energy. The power generation control application 110 receives a generator operating condition, such as a speed of the generator 4 and a current exciter current, from the generator 4 ,

When the internal combustion engine 2 starts, is the allowable torque, as in 3 less than the predetermined torque and causes the ECU 30 the generator 4 to stop the generation of electrical energy. In this case, the generator is terminated 4 based on a start interruption. Alternatively, if the internal combustion engine 2 in an accelerating operation, the allowable torque is less than the predetermined torque and ends the ECU 30 the generation of electrical energy by the generator 4 , In this case, the generator is terminated 4 based on an acceleration interruption. When the allowable torque is greater than or equal to the predetermined torque, the ECU controls 30 the generator 4 to generate the electrical energy, such that the load torque of the generator 4 is within the range of allowable torque. Consequently, the load torque of the generator exceeds 4 the permissible torque is not.

Below is one from the ECU 30 executed power generation control operation with reference to that in the 4 described flowchart described. The power generation control operation corresponds to a generator control operation. That in the 4 The flowchart shown is executed by a timer interruption in a predetermined period of time.

In S400 calculates the ECU 30 a maximum torque generated by the internal combustion engine 2 is producible based on a current engine speed. The maximum torque of the internal combustion engine 2 takes as in 3 shown in accordance with an increase in the engine speed. The ECU also calculates 30 in S420 the output torque of the engine 2 using equation (1). $$\begin{array}{l}\text{output torque}=\text{maximum torque}\times (\text{Torque efficiency of}\\ \text{Ansaugladewirkungsgrad})\times \left(\text{Torque efficiency of ignition timing}\right)\times \\ \left(\text{Torque efficiency of air-fuel ratio}\right)\end{array}$$

In the equation (1), a torque efficiency of the intake charge efficiency corresponds to a ratio of a current intake charge efficiency with respect to the intake charge efficiency in the case where the engine 2 generates the maximum torque; A torque efficiency of the ignition timing corresponds to a ratio of a current ignition timing with respect to the ignition timing in the case where the internal combustion engine 2 generates the maximum torque; and a torque efficiency of the air-fuel ratio corresponds to a ratio of a current air-fuel ratio with respect to the air-fuel ratio in the case where the engine 2 generates the maximum torque.

The ECU 30 controls the intake charge efficiency, the ignition timing, or the air-fuel ratio based on the request output torque to cause the engine 2 generates the request torque. The intake charge efficiency is controlled in accordance with an opening degree of a throttle device that corresponds to a throttle opening degree. The ignition timing is controlled using a spark plug. The air-fuel ratio is controlled in accordance with the throttle opening degree, a fuel injection amount or an EGR gas amount.

The ECU 30 estimates a change amount of the request torque based on a driving operation of a driver, an operating state of a transmission, or an operating state of the accessory. The driving operation includes, for example, an accelerator pedal operation, a steering operation, and a brake operation. Preferably, a sum of the amount of change and the output torque calculated from the equation (1) becomes the output torque of the internal combustion engine 2 used.

Consequently, even if the request torque is significantly changed with respect to a large acceleration or deceleration or on / off of the air conditioner, it may be Excess torque calculated from an equation (2) is protected from an excess state by adding the amount of change in advance to the output torque.

In S404 calculates the ECU 30 the surplus torque from the internal combustion engine 2 is producible, in addition to a momentary output torque from the internal combustion engine 2 is generated based on the maximum torque and the output torque by the equation (2). $$\text{Excess torque}=\text{maximum torque}-\text{output torque}$$

In S406 calculates the ECU 30 the request load torque. The ECU 30 estimates in advance power generation characteristic data of the request load torque with respect to the rotation speed of the generator 4 , the control voltage of the generator 4 and the excitation current of the generator 4 and stores the power generation characteristic data as a map in the ROM. The ECU 30 calculates a momentary load torque of the generator 4 using the map based on a current speed of the generator 4 , a current control voltage of the generator 4 and a current excitation current of the generator 4 ,

In S408 calculates the ECU 30 the permissible torque, that of the generator 4 can be assigned by equation (3). $$\text{Permissible torque}=\text{Excess torque}+\text{load torque}$$

The permissible torque corresponds to a maximum value of the load torque generated by the generator 4 can be used to generate the electrical energy. In the event that the entire surplus torque is the generator 4 When the allowable torque is assigned, when the request output torque greatly increases, the output torque becomes excessive and drivability deteriorates. Thus, preferably, a torque subtracting the margin from the allowable torque calculated from the equation (3) is used as a deductible allowable torque.

Preferably, filtering is performed with respect to the withdrawn allowable torque to occur the occurrence of a torque change shock due to a large change in the load torque of the generator 4 to reduce. The filtering may be a first order filtering performed by a first filter. The filtering may be performed only with respect to a change amount of the load torque or the allowable torque in an increasing direction.

Since the filtering with respect to the allowable torque is in the increasing direction, the torque change shock is restricted and a decrease in the engine speed can be restrained while the engine is running 2 operates in an idle state.

Further, a significant change of a power generation amount of the generator 4 and preventing heat generation of the battery due to a marked change in a charging current of the battery.

Preferably, the margin is variably set in accordance with the engine operating condition such as the engine speed or a water temperature. Consequently, since the margin becomes in accordance with an increase in the change of the output torque of the internal combustion engine 2 is set larger, the margin is set appropriately to reduce the occurrence of an engine stop while the torque is changed significantly or during the engine 2 works in idle mode.

When the allowable torque that is the generator 4 is assigned less than the predetermined torque, the load torque corresponding to the allowable torque can not be used to be greater than or equal to the predetermined torque. In this case it is, taking into account a property of the generator 4 , possible that the power generation amount can not be controlled accurately.

In S410 determines the ECU 30 whether the allowable torque is greater than or equal to the predetermined torque. If the ECU 30 determines that the allowable torque is greater than or equal to is predetermined torque (S410 = YES), the ECU advances 30 to S412 Ahead. In S412 controls the ECU 30 the generator 4 to generate the electric power based on a remaining battery capacity in the event that the load torque of the generator 4 in the range of the permissible torque.

In a power generation control of the generator 4 becomes the exciting current based on a power generation characteristic with respect to the rotational speed of the generator 4 and the control voltage of the generator 4 controlled. Alternatively, the control voltage based on the power generation characteristic with respect to the rotational speed of the generator 4 and the excitation current of the generator 4 controlled.

If the ECU 30 determines that the allowable torque is less than the predetermined torque (S410 = NO), the ECU proceeds 30 to S414 Ahead. In S414 blocks the ECU 30 the excitation current and ends the ECU 30 the generation of electrical energy by the generator 4 ,

Preferably, the predetermined torque used for the determination in S410 is set to a hysteresis value such that an increase value of the allowable torque is greater than a decrease value of the allowable torque. When the predetermined torque is fixed, the allowable torque increases and decreases near the predetermined torque, and the power generation control is prohibited from being repeatedly stopped and executed by the generator 4 to control.

According to the above embodiment, this becomes the generator 4 assigned allowable torque based on that of the internal combustion engine 2 generated output torque and that of the internal combustion engine 2 calculated excess torque. The power generation control is performed such that the generator 4 in the event that the load torque of the generator 4 in the range of the permissible torque works.

Consequently, if the internal combustion engine 2 starts or after an engine starting operation, the generator 4 be controlled to generate the electrical energy, in an area in which a rotation of the internal combustion engine 2 not disturbed. Accordingly, the starting power of the internal combustion engine 2 ensures and can stabilize the engine operating state including the idling operation.

The generator 4 can be easily controlled to generate the electric power, based on a general parameter corresponding to the allowable torque, regardless of the operating state of the internal combustion engine 2 , such as the engine starting operation, the idling operation, the acceleration operation or the deceleration operation.

(Further embodiment)

In the above embodiment, the power generation control of the generator is 4 on the gasoline engine 2 is applied described. However, the power generation control of the generator may be applied to a diesel engine.

When the power generation control is applied to a diesel engine, the torque efficiency of the intake charge efficiency is 100% because the throttle opening degree is usually fully open. Accordingly, in the equation (1), an intake charge efficiency element is 1, and thus this element can be omitted. When an ignition timing estimated over a combustion injection timing is used as the combustion start timing, the output torque is calculated from the equation (4). $$\begin{array}{l}\text{output torque}=\text{maximum torque}\times (\text{Torque efficiency of}\\ \text{ignition timing})\times \left(\text{Torque efficiency of air-fuel ratio}\right)\end{array}$$

The present invention is not limited to the above-described embodiments but may be variously modified within its scope.

Although the present invention is described above in connection with its embodiments, it should be understood that it is not limited to the embodiments and constructions. The present invention is intended to cover various modifications and equivalent arrangements. Furthermore, while the various combinations and configurations that are preferred have been disclosed, other combinations and configurations that include more, less, or only a single element should also be understood as included within the scope of the present invention.

Above, a generator controller is disclosed.

A generator controller has a surplus torque section ( S404 ), an allowable torque portion ( S408 ) and a power generation control section ( S409 ) on. The surplus torque section calculates an excess torque producible by an internal combustion engine in addition to an output torque generated by the internal combustion engine. The allowable torque portion calculates an allowable torque to be assigned to the generator based on the excess torque calculated by the surplus torque portion. The power generation control section controls generation of electric power of the generator such that a load torque applied to the generator is in a range of the allowable torque calculated by the allowance torque section.

Claims (13)

Generator controller with: an excess torque section (S404) that calculates an excess torque that is producible by an internal combustion engine (2) in addition to an output torque generated by the internal combustion engine (2); an allowance torque section (S408) that calculates an allowable torque to be assigned to a generator (4) based on the excess torque calculated by the surplus torque section (S404); - a power generation control section (S409) that controls generation of electric power of the generator (4) such that a load torque applied to the generator (4) is within a range of the allowable torque calculated by the allowance torque section (S408); and a load torque section (S406) that calculates the load torque applied to the generator (4) to generate electric power, wherein - the allowable torque portion (S408) calculates the allowable torque by adding the load torque calculated by the load torque portion (S406) to the excess torque. Generator controller after Claim 1 characterized in that it further comprises: - a maximum torque portion (S400) that calculates a maximum torque that is producible by the internal combustion engine (2); and an output torque section calculating the output torque, wherein the surplus torque section calculates a difference between the maximum torque calculated by the maximum torque section and the output torque calculated by the output torque section as the surplus torque. 8. Generator controller after Claim 2 characterized in that the output torque section (S402) calculates the output torque by multiplying the maximum torque by (i) a torque efficiency of the intake charge efficiency, (ii) a torque efficiency of the combustion start time, and (iii) a torque efficiency of the air-fuel ratio. Generator controller after Claim 3 characterized in that it further comprises: an estimated torque portion (S402) which estimates an amount of change of a required torque requested from the internal combustion engine (2) with respect to the output torque, wherein - the output torque portion (S402) calculates the output torque by an estimated torque estimated by the estimated torque section (S402) is added to a result of multiplying the maximum torque by (i) the intake efficiency efficiency, (ii) the torque efficiency of the combustion start time, and (iii) the air-fuel ratio torque efficiency. Generator controller after Claim 4 characterized in that the estimated torque portion (S402) estimates the estimated torque based on a driving operation of a driver and / or an operating state of a transmission and / or an operating state of the accessory. Generator controller after Claim 5 characterized in that the estimated torque portion (S402) estimates the estimated torque based on an acceleration operation of the driver. Generator controller after Claim 1 characterized in that the allowable torque portion (S408) controls a change of the allowable torque by filtering a result of adding the load torque to the surplus torque. Generator controller after Claim 7 characterized in that the allowable torque portion (S408) controls the change of the allowable torque in an increase direction by the filtering of the result of adding the load torque to the excess torque. Generator controller after Claim 7 or 8th , characterized in that the filtering is a first order filtering. Generator controller according to one of Claims 1 to 9 characterized in that the power generation control section (S409) controls an exciting current of the generator (4) based on a power generation characteristic with respect to a rotational speed of the generator (4) and a control voltage of the generator (4). Generator controller according to one of Claims 1 to 9 characterized in that the power generation control section (S409) controls a control voltage of the generator (4) based on a power generation characteristic with respect to a rotation speed of the generator (4) and an exciting current of the generator (4). Generator controller according to one of Claims 1 to 11 characterized in that the power generation control section (S409) stops generation of electric power by the generator (4) when the allowable torque is below a predetermined torque. Generator controller after Claim 12 characterized in that the predetermined torque is set to such a value that an increase value of the allowable torque is greater than a decrease value of the allowable torque.

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