JP2011200062A - Power generation control device for vehicle - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a power generation control device for vehicle that stabilizes engine rotation and recovers a power generation voltage when power generation restrained control is prohibited in response to reduction in the power generation voltage.SOLUTION: The power generation control device 2 for the vehicle includes: a voltage control circuit 206 for controlling an excitation current so that the power generation voltage becomes a first set value; an excitation current restrained control circuit 207 for restraining an increase in the excitation current when the excitation current is increased; and an excitation current restrained control prohibition/release circuit 208 for prohibiting, when the power generation voltage becomes equal to or lower than a predetermined second voltage lower than a predetermined first voltage during power generation restrained control, the power generation restrained control, and even when the power generation voltage becomes higher than the predetermined second voltage after the power generation restrained control is prohibited, maintaining the prohibited power generation restrained control until the power generation voltage becomes higher than a predetermined third voltage.

Description

  The present invention relates to a vehicle power generation control device that performs power generation control of a vehicle generator mounted on a passenger car, a truck, or the like.

  In recent years, in order to improve the fuel efficiency of vehicles, low idling and low friction have progressed, and torque fluctuations due to operation of auxiliary machines have come to greatly affect engine rotation fluctuations. As a technology for stabilizing engine rotation, idle control is achieved by performing a slow excitation control that suppresses a power generation increase speed of a vehicular generator during idling to prevent a sudden increase in generator torque. Things are known. At that time, when the electric load is large, the battery voltage decreases due to the suppression of power generation. When the battery terminal is in a large state or when the battery terminal is in a poor contact state, the power supply voltage of the in-vehicle device to which the operating power is supplied from the battery is greatly reduced. Causes malfunctions such as malfunction or system down.

  As a conventional technique for coping with the negative effects of such power generation suppression, if the power generation voltage drops below a predetermined value during gradual excitation control, the gradual excitation control is prohibited and the power generation voltage is reliably recovered, thereby causing malfunction of the in-vehicle device. A technique for avoiding this problem is known (for example, see Patent Document 1).

JP-A-9-107640 (page 3-6, FIG. 1-11)

  By the way, in the method disclosed in Patent Document 1, gradual excitation control (power generation suppression) is prohibited when the generated voltage becomes a predetermined value or less. However, when the generated voltage rises and falls across the predetermined value, gradual excitation control is performed. The prohibition and release (resumption of gradual excitation control) are frequently repeated. As a result, fluctuations in the engine rotation become large and difficult to stabilize, and recovery of the power supply voltage is difficult or slow. there were. In particular, the rotation of the vehicular generator driven by the engine fluctuates in synchronization with the ignition cycle of the engine, and the generated voltage fluctuates with this fluctuation in rotation. For this reason, if the generated voltage is in the vicinity of a predetermined value for which the gradual excitation control is prohibited, the generated voltage goes up and down with the predetermined value along with the rotation fluctuation, and the above phenomenon becomes remarkable.

  The present invention was created in view of such points, and its purpose is to achieve both stable engine rotation and recovery of generated voltage when power generation suppression is prohibited in response to a decrease in generated voltage. An object of the present invention is to provide a vehicular power generation control device that can perform the above.

  In order to solve the above-described problem, the vehicle power generation control device of the present invention controls the excitation current of the vehicle generator so that the power generation voltage of the vehicle generator driven by the engine becomes the first set value. Voltage control means for controlling, an excitation current suppression control means for suppressing an increase in the excitation current when the excitation current is increased by the voltage control means, and a generation voltage of the vehicle generator during the suppression control by the excitation current suppression control means. Suppression control prohibiting means for prohibiting suppression control by the excitation current suppression control means when the voltage becomes equal to or lower than a second predetermined voltage lower than a predetermined voltage of 1, and suppression control by the excitation current suppression control means is prohibited by the suppression control prohibiting means. When the generated voltage of the vehicular generator becomes higher than the second predetermined voltage after being turned on, the vehicle is higher than the second predetermined voltage and lower than the third predetermined voltage. Generation voltage of the generator and a suppression control prohibiting maintaining means for maintaining the prohibition suppression control by the suppression control prohibiting means to be higher.

  By providing a voltage hysteresis that changes the predetermined voltage that is the basis for prohibiting and canceling power generation suppression, it is possible to prevent fluctuations in power generation torque due to frequent switching of whether power generation is suppressed or not. Can be prevented and engine rotation can be stabilized. In addition, since a certain period of time is ensured until the prohibition state is canceled after the power generation suppression is once prohibited, the power supply voltage can be recovered.

  Moreover, it is desirable to set the difference between the above-mentioned third predetermined voltage and the second predetermined voltage to be larger than the fluctuation range of the generated voltage of the vehicle generator corresponding to the ignition control cycle of the engine. As a result, it is possible to prevent the inhibition and release of power generation suppression that is linked to the pulsation of engine rotation that occurs in synchronization with the engine ignition control cycle, and to achieve both stable engine rotation and recovery of the generated voltage. it can.

  Further, it is desirable to variably set the difference between the third predetermined voltage and the second predetermined voltage described above based on at least one of the rotational speed and temperature of the vehicular generator. Since the power generation capacity changes according to the rotational speed and temperature of the vehicular generator, the fluctuation range of the generated voltage accompanying the fluctuation in rotation also changes. Therefore, by varying the difference between the third predetermined voltage and the second predetermined voltage according to the rotation speed and temperature of the vehicle generator (for example, when the second predetermined voltage is constant, the third predetermined voltage is By varying the voltage value), it is possible to reliably achieve stable engine rotation and recovery of the generated voltage according to the power generation capacity.

  Moreover, it is desirable to variably set the difference between the third predetermined voltage and the second predetermined voltage described above based on information sent from the external control device. As a result, the degree of voltage hysteresis can be set based on various types of information collected by the external control device, and the engine rotation can be stabilized and the generated voltage can be reliably recovered.

  The external control device described above acquires at least one of the engine speed and the vehicle temperature, and determines the difference between the third predetermined voltage and the second predetermined voltage based on at least one of the engine speed and the vehicle temperature. It is desirable to variably set. Since the power generation capacity changes according to the engine speed and the vehicle temperature, the fluctuation range of the power generation voltage caused by the rotation fluctuation or the like also changes. Therefore, by varying the difference between the third predetermined voltage and the second predetermined voltage according to the engine speed and the vehicle temperature (for example, when the second predetermined voltage is constant, the value of the third predetermined voltage is It is possible to reliably stabilize the engine rotation and recover the power generation voltage according to the power generation capacity.

  Further, the vehicle power generation control device of the present invention includes a voltage control means for controlling the excitation current of the vehicle generator so that the power generation voltage of the vehicle generator driven by the engine becomes the first set value, and the voltage An excitation current suppression control unit that suppresses an increase in excitation current when the excitation current is increased by the control unit, and a power generation voltage of the vehicle generator is lower than the first predetermined voltage during the suppression control by the excitation current suppression control unit A suppression control prohibiting means for prohibiting suppression control by the excitation current suppression control means when the voltage becomes equal to or lower than a second predetermined voltage, and a predetermined time has elapsed since the suppression control by the excitation current suppression control means was prohibited by the suppression control prohibiting means. Until then, there is provided suppression control prohibition maintaining means for maintaining prohibition of suppression control by the suppression control prohibition means when the power generation voltage of the vehicle generator becomes higher than the second predetermined voltage. To have.

  By securing a certain amount of time (predetermined time) as a time interval from prohibiting power generation suppression to releasing it, it is possible to prevent fluctuations in power generation torque that accompany frequent switching of power generation suppression. It is possible to prevent the fluctuation of the engine rotation from increasing and to stabilize the engine rotation. In addition, since a certain period of time is ensured until the prohibition state is canceled after the power generation suppression is once prohibited, the power supply voltage can be recovered.

  Moreover, it is desirable that the above-described predetermined time be equal to or longer than a time corresponding to the engine ignition control cycle. As a result, it is possible to prevent the inhibition and release of power generation suppression that is linked to the pulsation of engine rotation that occurs in synchronization with the engine ignition control cycle, and to achieve both stable engine rotation and recovery of the generated voltage. it can.

  Moreover, it is desirable to variably set the predetermined time described above based on at least one of the rotational speed and temperature of the vehicular generator. The degree of pulsation of the generated voltage (cycle and pulsation width of the voltage) changes according to the rotation speed and temperature of the vehicular generator. Therefore, by varying the predetermined time set as the minimum value of the time interval from prohibiting power generation to releasing it according to the rotation speed and temperature of the vehicular generator, the degree of pulsation of the generated voltage can be reduced. Accordingly, it is possible to reliably achieve stable engine rotation and recovery of the generated voltage.

  Moreover, it is desirable to variably set the predetermined time described above based on information sent from the external control device. As a result, the degree of voltage hysteresis can be set based on various types of information collected by the external control device, and the engine rotation can be stabilized and the generated voltage can be reliably recovered.

  Further, it is desirable that the external control device described above acquires at least one of the engine speed and the vehicle temperature, and variably sets the predetermined time based on at least one of the engine speed and the vehicle temperature. The degree of pulsation of the generated voltage (cycle and pulsation width of the voltage) changes according to the engine speed and the vehicle temperature. Therefore, by varying the predetermined time set as the minimum value of the time interval from prohibiting power generation suppression to releasing it according to the engine speed and vehicle temperature, it is ensured according to the degree of pulsation of the power generation voltage. In addition, stable engine rotation and recovery of the generated voltage can be achieved.

It is a figure which shows the structure of the vehicle electric power generation control apparatus of one Embodiment. It is a figure which shows the change of the electric power generation voltage after electric load injection at the time of idling. It is a figure which shows the change of the engine speed after electric load injection at the time of idling. It is a figure which shows the modification of the vehicle electric power generation control apparatus which detects at least one of the rotation speed of a vehicle generator, and temperature, and performs electric power generation control. It is a figure which shows the modification of the vehicle electric power generation control apparatus which performs electric power generation control based on the information sent from an external control apparatus.

  Hereinafter, a vehicle power generation control device according to an embodiment to which the present invention is applied will be described with reference to the drawings.

  FIG. 1 is a diagram illustrating a configuration of a vehicle power generation control device according to an embodiment, and also illustrates a connection state between the vehicle power generation control device and a vehicle power generator or a battery. In FIG. 1, the vehicle power generation control device 2 performs power generation control so that the voltage of the output terminal (B terminal) of the vehicle generator 1 driven by the engine becomes the adjustment voltage set value. Further, the vehicle power generation control device 2 has a ground terminal (E terminal) in addition to the B terminal. The B terminal is connected to the battery 3 and various electric loads (not shown) via a predetermined charging line. The E terminal is connected to the frame of the vehicle generator 1. In FIG. 1, the vehicle power generation control device 2 is illustrated in parallel with the vehicle generator 1, but is actually built in the vehicle generator 1.

  The vehicle generator 1 is provided for full-wave rectification of the three-phase stator winding 101 included in the stator, the excitation winding 102 for magnetizing the rotor, and the three-phase output of the stator winding 101. The rectifier circuit 103 is configured. The control of the output voltage of the vehicular generator 1 is performed by appropriately intermittently controlling the supply of the excitation current to the excitation winding 102 by the vehicular power generation control device 2.

  Next, a detailed configuration and operation of the vehicle power generation control device 2 will be described. As shown in FIG. 1, the vehicle power generation control device 2 includes an N-channel MOS-FET 201, a freewheeling diode 202, a sense resistor 203, resistors 204 and 205, a voltage control circuit 206, an excitation current suppression control circuit 207, and an excitation current suppression control. A prohibit / cancel circuit 208 and an AND circuit 209 are provided.

  The MOS-FET 201 is connected in series to the excitation winding 102, and an excitation current flows through the excitation winding 102 when it is in an on state. The freewheeling diode 202 is connected in parallel to the exciting winding 102 and recirculates the exciting current when the MOS-FET 201 is off.

  The resistors 204 and 205 constitute a voltage dividing circuit, and a voltage obtained by dividing the output voltage (generated voltage) of the vehicle generator 1 by the voltage dividing circuit is applied to the voltage control circuit 206. The voltage control circuit 206 detects the generated voltage of the vehicular generator 1 based on the voltage applied from the voltage dividing circuit, and this generated voltage becomes an adjustment voltage setting value (first predetermined voltage, for example, 14V). The exciting current of the vehicular generator 1 is controlled. For example, the voltage control circuit 206 outputs a PWM signal having an on-duty proportional to the difference between the adjustment voltage setting value and the generated voltage. The PWM signal is input to the MOS-FET 201 as an excitation drive signal via the AND circuit 209, and the MOS-FET 201 is controlled to be turned on / off.

  The excitation current suppression control circuit 207 performs power generation suppression control that gradually increases the excitation current when the voltage control circuit 206 increases the excitation current. For example, the excitation current suppression control circuit 207 takes in the output signal of the previous AND circuit 209 and outputs a power generation suppression signal having an on-duty obtained by adding a predetermined increment to the duty ratio of this signal. This power generation suppression signal is input to the AND circuit 209. Even if the on-duty of the PWM signal output from the voltage control circuit 206 suddenly increases as a large electric load is applied, the on-duty of the power generation suppression signal output from the excitation current suppression control circuit 207 is a predetermined increment. Since it increases only at a determined speed, the on-duty of the excitation drive signal input from the AND circuit 209 to the MOS-FET 201 only increases gradually, and thus power generation suppression control is performed.

  The exciting current suppression control prohibiting / releasing circuit 208 is used when the power generation voltage of the vehicle generator 1 becomes lower than the second predetermined voltage lower than the first predetermined voltage during the power generation suppression control by the excitation current suppression control circuit 207. In addition, power generation suppression control by the excitation current suppression control circuit 207 is prohibited. Further, the excitation current suppression control prohibition / cancellation circuit 208 is configured so that the power generation voltage of the vehicle generator 1 becomes higher than the second predetermined voltage after prohibiting the power generation suppression control by the excitation current suppression control circuit 207. The power generation suppression control is prohibited until the power generation voltage becomes higher than the third predetermined voltage that is higher than the predetermined voltage 2 and lower than the first predetermined voltage. When the generated voltage further increases and exceeds the third predetermined voltage, the excitation current suppression control prohibition / cancellation circuit 208 cancels the prohibition of power generation suppression control, that is, instructs the excitation current suppression control circuit to resume the generation suppression control. 207.

  The prohibition of power generation suppression control by the excitation current suppression control prohibition / cancellation circuit 208 is to send an instruction to that effect to the excitation current suppression control circuit 207 and constantly generate a power generation suppression signal output from the excitation current suppression control circuit 207. This is done by maintaining a high level. Further, the second predetermined voltage described above is set to a value equal to or lower than the open-circuit voltage of the battery 3. As a result, it is possible to prevent the battery 3 from being excessively discharged by increasing the amount of power generated when the electric load suddenly increases.

  The voltage control circuit 206 described above corresponds to voltage control means, the excitation current suppression control circuit 207 corresponds to excitation current suppression control means, and the excitation current suppression control prohibit / release circuit 208 corresponds to suppression control prohibition means and suppression control prohibition maintenance means. .

  In the vehicle power generation control device 2 of the present embodiment, when the generated voltage changes in the vicinity of the adjustment voltage set value (first predetermined voltage) and the excitation current is small, the generation suppression control by the excitation current suppression control circuit 207 is performed. The PWM signal output from the voltage control circuit 206 is not input to the MOS-FET 201 as an excitation drive signal via the AND circuit 209, and the excitation current is controlled according to the excitation drive signal.

  Further, when the generated voltage drops below the adjustment voltage set value by turning on the electric load, the on-duty of the PWM signal output from the voltage control circuit 206 increases according to the degree of the voltage drop, but the excitation current suppression control circuit 207 Since power generation suppression control is performed, the excitation current gradually increases.

  In addition, when a large electric load is applied such that the generated voltage is equal to or lower than the second set value, the excitation current suppression control inhibit / cancel circuit 208 suppresses the excitation current in order to recover this large drop in the generated voltage. The power generation suppression control by the control circuit 207 is canceled (prohibited). This power generation suppression control prohibition state is maintained until the power generation voltage exceeds the third predetermined voltage.

  FIG. 2 is a diagram showing a change in the generated voltage after the electric load is turned on during idling. In FIG. 2, the horizontal axis indicates the passage of time, and the vertical axis indicates the generated voltage. The voltage change indicated by the dotted line B indicates that the power generation suppression control is prohibited when the power generation voltage is equal to or lower than the second predetermined voltage, and the power generation suppression control prohibition is canceled when the power generation voltage exceeds the second predetermined voltage. The conventional example is shown, and is shown for comparison with the voltage change of the present invention indicated by the solid line A.

  FIG. 3 is a graph showing changes in the engine speed after the electric load is applied during idling. In FIG. 3, the horizontal axis indicates the passage of time, and the vertical axis indicates the engine speed. The engine speed change indicated by the dotted line B indicates that the power generation suppression control is prohibited when the power generation voltage is equal to or lower than the second predetermined voltage, and the power generation suppression control is prohibited when the power generation voltage exceeds the second predetermined voltage. A prior art example is shown, which is shown for comparison with the voltage change of the present invention indicated by the solid line A.

  As shown in FIGS. 2 and 3, in the vehicle power generation control device 2 of the present embodiment, the predetermined voltage (second predetermined voltage and third predetermined voltage) that is a reference for prohibiting and canceling power generation is made different. By providing voltage hysteresis, it is possible to prevent fluctuations in power generation torque due to frequent switching of whether or not power generation is suppressed, so that fluctuations in engine rotation can be prevented from increasing and engine rotation can be stabilized. It becomes possible. In addition, since a certain period of time is ensured until the prohibition state is canceled after the power generation suppression is once prohibited, the power supply voltage can be recovered.

  By the way, the difference between the above-mentioned third predetermined voltage (voltage that cancels the prohibition of power generation suppression control and resumes power generation suppression control) and the second predetermined voltage (voltage that prohibits power generation suppression control) is the ignition of the engine. It is desirable to set it larger than the fluctuation range of the generated voltage of the vehicle generator 1 corresponding to the control cycle. For example, if the rotational speed at idle of an 8-cylinder engine is 700 rpm, the ignition control period is about 10 ms (= 1 / ((700 × 8) / 60)), and the engine rotation pulsation occurs in this period. The generated voltage of the generator 1 rises and falls within a predetermined fluctuation range in this cycle. By preventing the generated voltage from exceeding the third predetermined voltage even if the generated voltage fluctuates within this fluctuation range, it is prohibited to suppress power generation linked to the engine rotation pulsation generated in synchronization with the engine ignition control cycle. And repetitive release can be prevented, and both stable engine rotation and recovery of the generated voltage can be achieved.

  Further, it is desirable that the difference between the third predetermined voltage and the second predetermined voltage described above is variably set based on at least one of the rotational speed and temperature of the vehicular generator 1. FIG. 4 is a diagram showing a modification of the vehicle power generation control device that performs power generation control by detecting at least one of the rotational speed and temperature of the vehicle generator 1. The vehicle power generation control device 2A shown in FIG. 4 is different from the vehicle power generation control device 2 shown in FIG. 1 in that a temperature sensor 210 and a rotation detection circuit 211 are added.

  The temperature sensor 210 detects the temperature of the vehicle power generation control device 2A, that is, the temperature of the vehicle power generator 1 in which the vehicle power generation control device 2A is incorporated. For example, a thermistor or a diode is used, and the temperature of the vehicular generator 1 is detected based on the both-end voltages of these elements that change depending on the temperature. The higher the temperature detected by the temperature sensor 210, the lower the power generation capability of the vehicular generator 1, and thus it is considered that the fluctuation range of the generated voltage accompanying the rotation fluctuation becomes smaller. Accordingly, the higher the temperature, the smaller the difference between the third predetermined voltage and the second predetermined voltage is set. Conversely, the lower the temperature, the larger the difference between the third predetermined voltage and the second predetermined voltage. You only have to set it. This variable setting is performed in the exciting current suppression control prohibiting / releasing circuit 208.

  The rotation detection circuit 211 detects the rotation speed (generator rotation speed) of the vehicle generator 1 by monitoring the phase voltage appearing in any phase of the stator winding 101, and the detected generator rotation speed. The voltage corresponding to is output. The lower the number of rotations detected by the rotation detection circuit 211, the lower the power generation capability of the vehicular generator 1, so the fluctuation range of the generated voltage accompanying the fluctuation in rotation is considered to be smaller. Therefore, the lower the rotation speed, the smaller the difference between the third predetermined voltage and the second predetermined voltage. On the contrary, the higher the rotation speed, the difference between the third predetermined voltage and the second predetermined voltage. Should be set larger. This variable setting is performed in the exciting current suppression control prohibiting / releasing circuit 208.

  As described above, the power generation amount of the vehicular generator 1 changes in accordance with the rotation speed and temperature, so that the fluctuation range of the generated voltage caused by the rotation fluctuation and the like also changes. Therefore, by varying the difference between the third predetermined voltage and the second predetermined voltage in accordance with the rotational speed and temperature of the vehicle generator 1 (for example, when the second predetermined voltage is constant, the third By varying the value of the predetermined voltage), it is possible to reliably achieve stable engine rotation and recovery of the generated voltage according to the power generation capacity.

  The difference between the third predetermined voltage and the second predetermined voltage described above may be variably set based on information sent from the external control device. FIG. 5 is a diagram illustrating a modification of the vehicle power generation control device that performs power generation control based on information sent from the external control device. The vehicle power generation control device 2B shown in FIG. 5 is different in that a communication control circuit 213 is added to the vehicle power generation control device 2 shown in FIG.

  The communication control circuit 213 performs bidirectional serial communication (for example, LIN communication using a LIN (Local Interconnect Network) protocol) with the external control device 4 via the C terminal (communication terminal), and the external control device. 4 periodically transmits a power generation voltage and the like, and receives information (power generation instruction signal) periodically transmitted from the external control device 4.

  In addition to the function of controlling the engine 5, the external control device 4 detects the vehicle temperature (the temperature around the engine 5 and the vehicle generator 1) using the temperature sensor 6 and determines at least one of the engine speed and the vehicle temperature. The generated power generation instruction signal is transmitted to the vehicle power generation control device 2B. In the vehicle power generation control device 2 </ b> B, the power generation instruction signal is received by the communication control circuit 213, and at least one of the engine speed and the vehicle temperature is input to the excitation current suppression control prohibit / release circuit 208. The exciting current suppression control prohibiting / releasing circuit 208 variably sets the difference between the third predetermined voltage and the second predetermined voltage based on the engine speed input from the communication control circuit 213 and the like. A specific example of the variable setting is basically the same as in the case of the vehicle power generation control device 2A shown in FIG. That is, since the vehicle temperature and the temperature of the vehicle generator 1 are correlated, if the vehicle temperature is high, the power generation capacity of the vehicle generator 1 decreases. Further, since the engine speed and the speed of the vehicular generator 1 are in a one-to-one correspondence, the power generation capacity of the vehicular generator 1 is reduced when the engine speed is low. As described above, the difference between the third predetermined voltage and the second predetermined voltage is set small with respect to the decrease in the power generation capacity. In the opposite case, the difference between the third predetermined voltage and the second predetermined voltage is set. The difference is set large. In this manner, by setting the degree of voltage hysteresis based on various information collected by the external control device 4, it is possible to reliably achieve stable engine rotation and recovery of the generated voltage according to the power generation capacity. It becomes.

  In addition, this invention is not limited to the said embodiment, A various deformation | transformation implementation is possible within the range of the summary of this invention. For example, in the above-described embodiment, the presence or absence of power generation suppression is frequently performed by providing a voltage hysteresis that makes the predetermined voltage (second predetermined voltage and third predetermined voltage) different from the prohibition and cancellation of power generation suppression differ. However, instead of having voltage hysteresis, the prohibition cannot be canceled for a predetermined time from the time when the suppression of power generation is prohibited (so that the prohibited state is maintained), and the presence or absence of power generation suppression May be prevented from frequently switching. As a basic configuration in this case, the vehicle power generation control device 2 shown in FIG. 1 can be used as it is.

  The excitation current suppression control prohibition / cancellation circuit 208 shown in FIG. 1 is configured such that the power generation voltage of the vehicle generator 1 is a second predetermined voltage until a predetermined time elapses after the power generation suppression control by the excitation current suppression control circuit 207 is prohibited. Even if it becomes higher than that, the prohibition of power generation suppression control is maintained. When the generated voltage is higher than the second predetermined voltage when the predetermined time has elapsed, the exciting current suppression control prohibition / cancellation circuit 208 cancels the prohibition of the power generation suppression control, that is, instructs to restart the power generation suppression control. This is performed for the excitation current suppression control circuit 207.

  By securing a certain amount of time (predetermined time) as a time interval from prohibiting power generation suppression to releasing it, it is possible to prevent fluctuations in power generation torque that accompany frequent switching of power generation suppression. It is possible to prevent the fluctuation of the engine rotation from increasing and to stabilize the engine rotation. In addition, since a certain period of time is ensured until the prohibition state is canceled after the power generation suppression is once prohibited, the power supply voltage can be recovered.

  Further, it is desirable that the above-mentioned predetermined time is equal to or longer than a time corresponding to the engine ignition control cycle. As a result, it is possible to prevent the inhibition and release of power generation suppression that is linked to the pulsation of engine rotation that occurs in synchronization with the engine ignition control cycle, and to achieve both stable engine rotation and recovery of the generated voltage. it can.

  Further, the predetermined time described above may be variably set based on at least one of the rotational speed and temperature of the vehicular generator 1. As a basic configuration in this case, the vehicle power generation control device 2A shown in FIG. 4 can be used as it is. The degree of pulsation of the generated voltage (cycle and pulsation width of the voltage) changes according to the rotation speed and temperature of the vehicular generator 1. Therefore, the degree of pulsation of the generated voltage is varied by varying the predetermined time set as the minimum value of the time interval from prohibiting power generation to releasing it according to the rotational speed and temperature of the vehicular generator 1. Accordingly, it is possible to reliably achieve stable engine rotation and recovery of the generated voltage.

  The predetermined time described above may be variably set based on information sent from the external control device. As a basic configuration in this case, the vehicle power generation control device 2B shown in FIG. 5 can be used as it is. As a result, it becomes possible to variably set a predetermined time as a time delay from prohibiting the power generation suppression control to canceling the prohibition based on various information collected by the external control device 4, thereby reliably rotating the engine. It is possible to stabilize the power generation and recover the generated voltage.

  Specifically, it is conceivable that at least one of the engine speed and the vehicle temperature is acquired by the external control device 4, and the predetermined time described above is variably set based on at least one of the engine speed and the vehicle temperature. The degree of pulsation of the generated voltage (cycle and pulsation width of the voltage) changes according to the engine speed and the vehicle temperature. Therefore, by varying the predetermined time set as the minimum value of the time interval from prohibiting power generation suppression to releasing it according to the engine speed and vehicle temperature, it is ensured according to the degree of pulsation of the power generation voltage. In addition, stable engine rotation and recovery of the generated voltage can be achieved.

  Further, in the above-described embodiment, the relationship with the idle state is not particularly mentioned, but the above-described power generation is performed at idle time (or at a predetermined rotation speed or less including idle time) when the engine rotation is particularly unstable. The inhibition control may be prohibited and canceled. As a result, it is possible to avoid a situation in which engine stall occurs during idling, where the engine rotation is likely to be unstable, or the power supply voltage (power generation voltage) decreases and does not recover.

  As described above, according to the present invention, by providing a voltage hysteresis that varies the predetermined voltage that is a reference for prohibition and cancellation of power generation suppression, fluctuations in power generation torque that accompany frequent switching of power generation suppression are determined. Therefore, it is possible to prevent fluctuations in engine rotation from increasing and to stabilize engine rotation. In addition, since a certain period of time is ensured until the prohibition state is canceled after the power generation suppression is once prohibited, the power supply voltage can be recovered.

DESCRIPTION OF SYMBOLS 1 Vehicle generator 2, 2A, 2B Vehicle power generation control device 3 Battery 4 External control device 5 Engine 6, 210 Temperature sensor 101 Stator winding 102 Excitation winding 103 Rectifier circuit 201 N channel MOS-FET
202 Freewheeling diode 203 Sense resistor 204, 205 Resistor 206 Voltage control circuit 207 Excitation current suppression control circuit 208 Excitation current suppression control prohibition / release circuit 209 AND circuit 211 Rotation detection circuit 213 Communication control circuit

Claims (10)

Voltage control means for controlling the excitation current of the vehicular generator so that the generated voltage of the vehicular generator driven by the engine becomes a first set value;
Excitation current suppression control means for suppressing an increase in excitation current when the excitation current is increased by the voltage control means;
During the suppression control by the excitation current suppression control means, the suppression control by the excitation current suppression control means is performed when the generated voltage of the vehicle generator becomes equal to or lower than a second predetermined voltage lower than the first predetermined voltage. Suppression control prohibiting means to prohibit,
When the power generation voltage of the vehicular generator becomes higher than the second predetermined voltage after the suppression control by the excitation current suppression control unit is prohibited by the suppression control prohibiting unit, the second predetermined voltage is exceeded. Suppression control prohibition maintaining means for maintaining prohibition of suppression control by the suppression control prohibition means until the power generation voltage of the vehicle generator becomes higher than a third predetermined voltage that is higher than the first predetermined voltage.
A vehicle power generation control device comprising: In claim 1,
The difference between the third predetermined voltage and the second predetermined voltage is set to be larger than the fluctuation range of the generated voltage of the vehicular generator corresponding to the ignition control cycle of the engine. Control device. In claim 1 or 2,
The vehicle power generation control device characterized in that a difference between the third predetermined voltage and the second predetermined voltage is variably set based on at least one of the rotational speed and temperature of the vehicle generator. In claim 1 or 2,
A power generation control device for a vehicle, wherein the difference between the third predetermined voltage and the second predetermined voltage is variably set based on information sent from an external control device. In claim 4,
The external control device acquires at least one of the engine speed and the vehicle temperature,
The vehicle power generation control device, wherein the difference between the third predetermined voltage and the second predetermined voltage is variably set based on at least one of the engine speed and the vehicle temperature. Voltage control means for controlling the excitation current of the vehicular generator so that the generated voltage of the vehicular generator driven by the engine becomes a first set value;
Excitation current suppression control means for suppressing an increase in excitation current when the excitation current is increased by the voltage control means;
During the suppression control by the excitation current suppression control means, the suppression control by the excitation current suppression control means is performed when the generated voltage of the vehicle generator becomes equal to or lower than a second predetermined voltage lower than the first predetermined voltage. Suppression control prohibiting means to prohibit,
When the generation voltage of the vehicular generator becomes higher than the second predetermined voltage until a predetermined time has elapsed from when the suppression control by the excitation current suppression control unit is prohibited by the suppression control prohibiting unit, Suppression control prohibition maintaining means for maintaining prohibition of suppression control by the suppression control prohibition means,
A vehicle power generation control device comprising: In claim 6,
The vehicular power generation control device characterized in that the predetermined time is equal to or longer than a time corresponding to an engine ignition control cycle. In claim 6 or 7,
The vehicle power generation control device, wherein the predetermined time is variably set based on at least one of a rotation speed and a temperature of the vehicle generator. In claim 6 or 7,
The power generation control device for a vehicle, wherein the predetermined time is variably set based on information sent from an external control device. In claim 9,
The external control device acquires at least one of the engine speed and the vehicle temperature,
The power generation control device for a vehicle, wherein the predetermined time is variably set based on at least one of the engine speed and the vehicle temperature.

Images