JPH11136806A - Power generation control device for hybrid vehicle - Google Patents

Abstract

(57) [Summary] (with correction) [PROBLEMS] To improve the response performance of generated power control by an engine-driven generator. SOLUTION: A rotation speed command value N * and a first torque command value T * of an engine drive generator 3 for generating required power are calculated, and a rotation speed detection value N of the engine drive generator 3 is calculated as a rotation speed. The second torque command value T1 * of the generator 3 is calculated so as to match the command value N *. The second torque command value T1 * is limited based on the rotation speed detection value N and the rotation speed command value N *, and the torque of the generator 3 is reduced to the second torque command value T1 *.
And the engine 4 is controlled such that the second torque command value T1 * matches the first torque command value T *. When changing the required generated power of the engine-driven generator, good responsiveness is obtained without the actual generated power overshooting or undershooting, and no parameter is required to adjust the responsiveness, reducing the adjustment man-hour. You.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an apparatus for controlling the power generated by an engine generator in a hybrid vehicle.

[0002]

2. Description of the Related Art There is known a power generation control device for a hybrid vehicle that uses a motor as a driving source for driving, generates electric power by an engine driven generator, charges a battery, and supplies power to the driving motor. (See, for example, JP-A-8-65813). In this type of device, required electric power is generated by the generator while controlling the rotation speed of the generator by the engine.

However, since the control system for controlling the rotation speed of the engine includes mechanical elements, the response speed is slower than that of the control system of the generator using only electric elements, and the required power generation is changed. Poor responsiveness,
There is a problem that the adjustment is difficult.

An object of the present invention is to improve the response performance of generated power control by an engine-driven generator.

[0005]

[Means for Solving the Problems]

(1) The invention of claim 1 is applied to a power generation control device for a hybrid vehicle that generates required power by an engine-driven generator and supplies the generated power to a battery and / or a traveling motor. A first calculating means for calculating a rotation speed command value and a first torque command value of the engine drive generator for generating required power; a detection means for detecting a rotation speed of the engine drive generator; Second calculating means for calculating a second torque command value of the generator for matching the detected rotation speed to the rotation speed command value, and a second torque based on the detected rotation speed and the rotation speed command value. Limiting means for limiting the command value; generator control means for controlling the generator so that the torque of the generator matches the second torque command value; and a second torque command value corresponding to the first torque command value. Engine control means for controlling the engine so that they match. (2) In the power generation control device for a hybrid vehicle according to the second aspect, when the rotation speed command value is changed by the limiting means, the second torque command is maintained until the rotation speed detection value reaches the rotation speed command value. The value is limited to a value before the rotation speed command value changes. (3) In the power generation control device for a hybrid vehicle according to claim 3, the engine control means calculates a throttle opening command value for making the second torque command value equal to the first torque command value, and sets the throttle valve. The drive is controlled.

[0006]

According to the present invention, when the required generated power of the engine-driven generator is changed, the actual generated power does not overshoot or undershoot.
In addition to obtaining good responsiveness, there are no parameters for adjusting the responsiveness, and the number of adjustment steps is reduced.

[0007]

DESCRIPTION OF THE PREFERRED EMBODIMENTS An embodiment in which the present invention is applied to a power generation control device of a series hybrid vehicle SHEV will be described. FIG. 1 is a diagram showing a configuration of an embodiment.
The power train of the vehicle includes a three-phase synchronous motor 1 as a driving source for driving, a battery 2 for supplying electric power to the motor 1,
A three-phase synchronous generator 3 for supplying electric power to the motor 1 and the battery 2 and an engine 4 for driving the generator 3 are provided. Note that the rotor of the generator 3 is directly connected to the output shaft of the engine 4. The motor 1 is provided with a rotation sensor 5 for detecting the rotation speed and the rotation position, and a current sensor 6 for detecting a three-phase current flowing through the motor 1. The engine 4 is provided with a rotation sensor 7 for detecting the rotation speed N and the rotation position of the engine 4 and the generator 3. Further, the generator 3 is provided with a current sensor 8 for detecting a three-phase current flowing through the generator 3.

The power generation output calculation circuit 9 calculates the required power P * based on the state of charge SOC of the battery 2, the running state of the vehicle, the operating state of the engine 4, and the like, and further generates the required power P *. The rotation speed command value N * of the engine 4 and the generator 3 and the power generation torque command value T * of the generator 3 are calculated.

Here, it is considered that the generator 3 driven by the engine 4 and generating power is generating negative torque.
In this specification, the negative torque of the generator 3 is referred to as power generation torque. Since the rotation speeds of the generator 3 and the engine 4 are the same, if the power generation efficiency of the generator 3 and the operation efficiency of the engine 4 are ignored, the power generation torque of the generator 3 becomes equal to the output torque of the engine 4. On the other hand, the electric motor 1 generates a positive torque, that is, a driving torque to propel the vehicle, and generates a negative torque, that is, a regenerative torque, to brake the vehicle.

The rotation speed control circuit 10 calculates a power generation torque command value T1 * for making the rotation speed detection value N by the rotation sensor 7 coincide with the rotation speed command value N * by, for example, proportional integral control. 3 is controlled. When the rotation speed command value N * changes, the torque limiting circuit 11 limits the power generation torque command value T1 * until the rotation speed detection value N reaches the command value N * to generate the power generation torque command value T2. Output *. The vector operation circuit 12
A current command value of the generator 3 is calculated using the generated torque command value T2 * and various parameters of the generator 3. For example,
A dq coordinate system that rotates together with the rotor of the generator 3 is set, and a q-axis current command value iq * proportional to the generated torque command value T2 * is calculated by the following equation.

Eq * = T2 * / (p · φ) In Equation 1, p is the number of pole pairs of the generator 3 and φ is the generator 3
Armature winding interlinkage magnetic flux number. Since the generator 3 is a synchronous generator, the d-axis current id * corresponding to the field magnetic flux component
Is 0.

The d-axis current id * according to the detected rotational speed N of the three-phase synchronous generator 3 and the terminal voltage of the battery 2
If is set to a negative value, a field weakening effect can be obtained.

Also, a three-phase induction generator can be used as the generator 3. In this case, the generated torque can be controlled by the well-known vector control of the induction motor, similarly to the synchronous generator 3 described above.

The current control inverter 13 detects the current value of the generator 3 based on the rotation speed N of the generator 3 by the rotation sensor 7 and the current value of the three-phase synchronous generator 3 by the current sensor 8. The AC power generated by the three-phase synchronous generator 3 is converted into DC power and supplied to the battery 2 while controlling so as to match the command value. More specifically, based on the rotation position of the rotor of the generator 3 detected by the rotation sensor 7, the above-described two-phase currents iq * and id *
Is converted into a three-phase AC current, and the drive voltage of the generator 3 is controlled such that the detected current value matches the current command value.

The torque control circuit 14 calculates a throttle opening command value α * such that the generated torque command value T2 * becomes the generated torque command value T *. As described above, if the power generation efficiency of the generator 3 and the operation efficiency of the engine 4 are ignored, the power generation torque Tg of the generator 3 during power generation and the output torque Te of the engine 4 are equal. Further, since the generator 3 must output a generated torque equal to the command value T * in order to obtain the required generated power P *, the final generated torque command value T2 * for the generator 3 is converted to the required generated power P *. Must be matched with the generated torque command value T * that satisfies the following condition. Therefore, by controlling the output torque Te of the engine 4 so that T2 * matches T *, the output torque Te of the engine 4 and the power generation torque of the generator 3 are made equal. The operating efficiency of the engine 4 during power generation and the loss due to the power generation efficiency of the generator 3 can be adjusted by the efficiency η in the calculation of the required generated power P *.

The throttle control circuit 15 controls the opening α of the throttle valve 16 so as to be a command value α *.
The engine control device 17 detects the operating state of the engine 4 using various sensors such as a rotation sensor 7, an intake air amount sensor (not shown), an exhaust gas sensor, and a cooling water temperature sensor, and controls the fuel injection and ignition of the engine 4. Perform timing control, etc.

The vehicle drive torque calculation circuit 18 calculates a torque command value T 'of the electric motor 1 based on the operation of the occupant detected by an accelerator sensor, a brake sensor, a vehicle speed sensor and the like (not shown) and the running state of the vehicle. . The vector calculation circuit 19 calculates a current command value of the electric motor 1 based on the electric motor torque command value T ′ and various parameters of the electric motor 1. The current control inverter 20 calculates the rotation speed of the electric motor 1 by the rotation sensor 5 and the current detection value of the three-phase synchronous motor 1 by the current sensor 6,
While controlling the detected current value of the motor 1 to be equal to the current command value, the DC power of the battery 2 is converted into AC power to drive the motor 1, and the AC regenerative power from the motor 1 is inverted to DC power. It is converted and supplied to the battery 2.

The power generation output operation circuit 9, the rotation speed control circuit 10, the torque limiting circuit 11, the vector operation circuit 12,
Current control inverter 13, torque control circuit 14, throttle opening control circuit 15, vehicle drive torque calculation circuit 1
8, vector operation circuit 19, current control inverter 20
Is composed of an electronic circuit centered on a microcomputer.

Next, the operation of the embodiment will be described. In order to make the operation of the embodiment easy to understand, an operation without the torque limiting circuit 11 will be described first with reference to FIG. 2 which is a time chart of a control result. In this case, the generated torque command value T2 * = T1 *.

In FIG. 2, the required power P * generated by the power output calculation circuit 9 changes from P1 to P2 at time t1,
(A) shows the rotational speed command value N * and the detected rotational speed value N when the power changes from P2 to P1 at time t2, and (b) shows the generated torque command value T *, the generated torque command value T1 * and the actual value. (C) shows the throttle opening command value α * and the actual throttle opening α. Also,
(D) shows the actual engine torque Te, and (e) shows the required generated power P * (= | N * · T * |) and the actual generated power P
(= | N · Tg |). Here, the required generated power P1
In this case, the rotation speed command value of the generator 3 is N1, the generation torque command value is T1, the power generation efficiency is η1, and the required power generation P2
Assuming that the rotational speed command value of the generator 2 is N2, the generated torque command value is T2, and the power generation efficiency is η2, the required generated powers P1 and P2 are expressed as follows.

P1 = N1 · T1 / η1, P2 = N2 · T2 / η2

The torque control system of the generator 3 includes a vector operation circuit 12, a current control inverter 13, and a rotation sensor 7.
And the windings of the generator 3. In this generator torque control system, a closed loop is formed only by electric elements, and a power generation torque command value T
The response of the output torque Tg of the generator 3 to 1 * is fast.
Therefore, the feedback gain in the rotation speed control system including the rotation speed control circuit 10 can be set high, and the rotation speed detection value N quickly follows the rotation speed command value N * as shown in FIG. ing.

At time t1, when the power generation torque command value T * increases from -Tg1 to -Tg2, the throttle opening command value α * increases from α1 to α2, and the actual throttle opening α changes to the command value. Follow and increase. Then, an air amount proportional to the actual throttle opening α is drawn into the engine 4, and fuel injection control, ignition timing control, and the like are performed in accordance with the drawn air amount. As a result, the output torque Te of the engine 4 increases from Te3 to Te4. At this time, the output torque Te4 of the engine 4 is balanced with the total value of the generated torque -Tg2 of the generator 3 and the load torque such as friction, and the rotation speed is maintained at N2.

Here, the torque control system of the engine 4 includes a torque control circuit 14, a throttle opening control circuit 15, a throttle valve 16, an opening sensor (not shown), and the like. The torque control system of this engine 4
Since it includes mechanical elements such as a throttle valve actuator and an intake air system, the feedback gain cannot be set high, and the response of the output torque Te of the engine 4 to the torque command value is slower than the torque control system of the generator 3. .

As described above, the rotation speed N of the generator 3 and the engine 4 is controlled by the rotation speed control system of the generator 3 so as to match the rotation speed command value N *, and the response of the control is fast. At times t1 and t2, the required generated power P *
When the rotation speed command value N * and the power generation torque command value T * change with the change of the rotation speed, the rotation speed N controlled by the rotation speed control system of the generator 3 quickly follows the command value N *, The engine torque Te controlled by the torque control system of the engine 4 has a response delay. Since the rotation speed control system of the generator 3 operates to compensate for the response delay of the engine torque Te, as shown in FIG. 2B, the power generation torque command value T1 at times t1 and t2.
* (= T2 *) swings in the direction opposite to the generated torque command value T *. That is, the torque control system of the generator 3 attempts to compensate for the delay in the rise of the engine torque by the output torque of the generator 3. As a result, the generated power P also changes in the direction opposite to the required generated power P *, and the charging power of the battery 2 becomes unstable, which is not preferable.

In order to eliminate such a problem, the present embodiment includes a torque limiting circuit 11. FIG. 3 is a time chart showing a control result in the case where the torque limiting circuit 11 is provided, and the control conditions and display contents are the same as those in FIG. The operation of this embodiment will be described with reference to FIG. When the rotation speed command value N * changes, the torque limiting circuit 11 maintains the generated torque command value T1 * until the detected rotation speed value N reaches the command value N *. In other words, t1 to t3 until the rotation speed N reaches the command value N * is the generated torque command value T1 * =
Tg1 is maintained, and the generated torque command value T2 * = Tg1.
During that time, the torque control circuit 14 increases the throttle opening command value α * according to the difference between the generated torque command value T * and the generated torque command value T2 *. As a result, the output torque Te of the engine 4 increases, and the rotation speed increases to N2. When the rotation speed reaches N2 at time t3, the torque limiting circuit 1
Since the torque limiting function of 1 is released, the power generation torque
The engine torque increases to Tg2 and to Te4. The same operation is performed between times t2 and t4.

As described above, since the rotation speed N and the generation torque Tg of the generator 3 are controlled well both in a steady state and in a transitional state, the generated power P is prevented from spike-like splattering and adversely affects the battery 2. Can be avoided.

In the configuration of the above embodiment, the generator 3 is an engine-driven generator, the engine 4 is an engine, the battery 2 is a battery, the motor 1 is a running motor, and the power generation output calculation circuit 9 is 1, a rotation sensor 7 serves as a detection means, a rotation speed control circuit 10 serves as a second calculation means, a torque limiting circuit 11 serves as a limiting means, a vector calculation circuit 12, a current control inverter 13, a rotation sensor 7 and The current sensor 8 constitutes the generator control means, and the torque control circuit 14, the throttle opening control circuit 15, the engine control device 17 and the rotation sensor 7 constitute the engine control means.

In the above-described embodiment, an example is shown in which the present invention is applied to a series hybrid vehicle SHEV. However, the present invention is not limited to a series hybrid vehicle. A series-parallel hybrid vehicle S that sometimes runs on an engine
It can be applied to PHV. In addition, the generator 3 and the electric motor 1
Is not limited to a three-phase synchronous machine, and a three-phase induction machine may be used. Further, a power capacitor (electric double layer capacitor) can be used as the battery 2 in addition to a general battery. Furthermore, in the above-described embodiment, an example in which the generator is directly connected to the engine has been described, but the engine and the generator may be connected by a power transmission mechanism.

[Brief description of the drawings]

FIG. 1 is a diagram showing a configuration of an embodiment.

FIG. 2 is a time chart illustrating a control result according to an embodiment when there is no torque limiting function;

FIG. 3 is a time chart showing a control result of one embodiment when a torque limiting function is provided.

[Description of Signs] 1 motor 2 battery 3 generator 4 engine 5 rotation sensor 6 current sensor 7 rotation sensor 8 current sensor 9 power generation output operation circuit 10 rotation speed control circuit 11 torque limiting circuit 12 vector calculation circuit 13 current control inverter 14 torque Control circuit 15 Throttle opening control 16 Throttle valve 17 Engine control device 18 Vehicle drive torque calculation circuit 19 Vector calculation circuit 20 Current control inverter

Claims (3)

[Claims] 1. A power generation control device for a hybrid vehicle that generates required power by an engine-driven generator and supplies the required power to a battery and / or a driving motor, wherein a rotation speed of the engine-driven generator for generating the required power is provided. First calculating means for calculating a command value and a first torque command value; detecting means for detecting a rotation speed of the engine-driven generator; and for matching the rotation speed detection value with the rotation speed command value. Calculating a second torque command value of the generator
Calculating means; limiting means for limiting the second torque command value based on the rotation speed detection value and the rotation speed command value; and wherein the torque of the generator matches the second torque command value. Generator control means for controlling the generator as described above, and engine control means for controlling the engine so that the second torque command value matches the first torque command value. Power generation control device for hybrid vehicles. 2. The power generation control device for a hybrid vehicle according to claim 1, wherein the limiting unit is configured to determine whether the rotation speed command value reaches the rotation speed command value when the rotation speed command value changes. During the period, the second torque command value is limited to a value before the rotation speed command value changes. 3. The power generation control device for a hybrid vehicle according to claim 1, wherein said engine control means includes a throttle for causing said second torque command value to coincide with said first torque command value. A power generation control device for a hybrid vehicle, which calculates an opening command value and drives and controls a throttle valve.