JP2021027701A - Power control device and power control method - Google Patents

Abstract

To provide a power control device and a power control method, capable of inhibiting system abnormality from being caused by excessive power generation.SOLUTION: A power control device according to an embodiment comprises a detection unit and a load control unit. The detection unit detects excessive power generation of a power generator for supplying power generated by operation of an internal combustion engine to a storage battery and a load. When excessive power generation is detected by the detection unit, the load control unit performs control of increasing an amount of power consumption in the load more than a normal amount.SELECTED DRAWING: Figure 2

Description

The present invention relates to a power control device and a power control method.

Conventionally, in a power generation system in which the driving force of an engine, which is a power source of a vehicle, is transmitted to a generator to generate electricity, there is a power control device that controls the supply of the generated power to a storage battery or an electric load. The power control device controls the amount of power generated by the generator, for example, based on the amount of charge to the storage battery and the power consumption of the electric load.

JP-A-2009-27812

However, in the prior art, for example, when excessive power generation occurs due to an abnormality of the generator, the amount of power generation exceeds the consumption of the storage battery and the electric load, the generator becomes an overvoltage / overcurrent state, and the generator fails. There was a risk that an abnormality would occur in the power generation system. Further, even if the generator is normal, for example, when traveling on a relatively long downhill, there is a risk of causing excessive power generation due to an increase in the amount of power generated by regeneration.

The present invention has been made in view of the above, and an object of the present invention is to provide a power control device and a power control method capable of suppressing the occurrence of system abnormalities due to excessive power generation.

In order to solve the above-mentioned problems and achieve the object, the power control device according to the present invention includes a detection unit and a load control unit. The detection unit detects the excess power generation of the generator that supplies the electric power generated by the operation of the internal combustion engine to the storage battery and the load. When the overpower generation is detected by the detection unit, the load control unit controls to increase the power consumption of the load more than a normal amount.

According to the present invention, it is possible to suppress the occurrence of system abnormalities due to excessive power generation.

FIG. 1A is a diagram showing an outline of a power control method according to an embodiment. FIG. 1B is a diagram showing an outline of a power control method according to an embodiment. FIG. 2 is a block diagram showing a configuration of a power control device according to an embodiment. FIG. 3 is a diagram showing a blocking process by the blocking unit. FIG. 4 is a flowchart showing a procedure of processing executed by the power control device according to the embodiment.

Hereinafter, the power control device and the power control method according to the embodiment will be described in detail with reference to the accompanying drawings. The present invention is not limited to the embodiments shown below.

First, the outline of the power control method according to the embodiment will be described with reference to FIGS. 1A and 1B. 1A and 1B are diagrams showing an outline of a power control method according to an embodiment. 1A and 1B show a power generation system S including a power control device according to an embodiment.

The power generation system S shown in FIG. 1A is, for example, a system mounted on a hybrid vehicle powered by an engine, and is a so-called mild hybrid system that assists driving the engine by a motor. In the power generation system S, the driving of the engine is assisted by rotating the motor when starting or traveling at low speed. Further, in the power generation system S, power is generated by regeneration from the engine to the generator during deceleration.

As shown in FIG. 1A, the power generation system S includes a power control device 1, an engine 10, a power transmission mechanism 11, an MG (motor generator) 12, a DCDC converter 13, a load 14, and a LiB (lithium ion battery). ) 15 and PbB (lead battery) 16.

The engine 10 is a power source for traveling, and is, for example, an internal combustion engine that uses gasoline, hydrogen, or the like as fuel. The power transmission mechanism 11 is a mechanism that transmits the driving force of the engine 10 to the MG 12. Further, the power transmission mechanism 11 transmits the rotational force of the MG 12 for assisting the driving of the engine 10 to the engine 10.

The MG 12 is a generator that supplies electric power generated by the operation of the engine 10 that is an internal combustion engine to the LiB 15 and the load 14, and is a generator including a motor (not shown). For example, during acceleration, the MG 12 rotates the motor with the electric power supplied from the LiB 15 to transmit the rotational force of the motor to the power transmission mechanism 11 to assist the driving of the engine 10. Further, the MG 12 functions as a generator during deceleration. Specifically, the MG 12 receives the driving force of the engine 10 due to the deceleration via the power transmission mechanism 11, and rotates the motor by the driving force to generate electric power. Then, the MG 12 supplies the generated electric power to the load 14 and the LiB 15.

The DCDC converter 13 transforms (steps down or boosts) the power supplied from the MG 12 and the LiB 15 and supplies the power to the load 14.

The load 14 is an electric device that consumes electric power, and examples thereof include a navigation device, audio, an air conditioner, and a wiper. Alternatively, the load 14 may be a vehicle control device that controls the vehicle, such as a PCS (Pre-crash Safety System) or an AEB (Advanced Emergency Braking System). The load 14 temporarily increases the power consumption when the MG 12 is overpowered by the control of the power control device 1, and the details will be described later.

LiB15 is, for example, a 48V storage battery. At the time of excessive power generation of MG12, LiB15 cuts off the electric circuit by turning off the relay R provided in the electric circuit between MG12 and LiB15, which will be described later.

The PbB 16 is, for example, a 12V storage battery, which supplies electric power to the load 14 and stores electric power supplied from MG 12 and LiB 15.

Here, as shown in FIG. 1A, the power generation amount of the MG 12 is controlled so as to be the total value of the charge amount of the LiB15 and the consumption amount of the load 14. That is, the MG 12 is controlled to generate electric power for charging the LiB 15 and consuming the LiB 15 in just proportion.

However, conventionally, when overpower generation occurs due to an abnormality of MG, for example, the amount of power generation exceeds the total value of the amount of charge of LiB and the amount of load consumed, so that the inside of MG becomes overvoltage / overcurrent. There was a risk of causing an abnormality in the power generation system such as an MG failure. Further, even if the MG is normal, for example, when traveling on a relatively long downhill, there is a risk of causing excessive power generation due to an increase in the amount of power generation due to regeneration.

Therefore, in the power control method according to the embodiment, when the MG 12 is excessive power generation, the power consumption of the load 14 is intentionally increased to consume the excess power.

Specifically, as shown in FIG. 1B, in the power control method according to the embodiment, first, the excess power generation of MG12 is detected (step S1). The details of the method for detecting excess power generation will be described later.

Subsequently, in the power control method according to the embodiment, when excessive power generation of the MG 12 is detected, the power consumption of the load 14 is controlled to be increased from the normal amount (step S2). The normal amount referred to here is, for example, the total power consumption of all the loads 14, and is the amount of power required for the load 14 to operate as requested by the user (user operation). Further, the normal amount may be the power consumption amount for each load 14.

As a method of increasing the power consumption of the load 14 from the normal amount, for example, there is a method of operating the load 14 which is not currently operating, a method of increasing the operating amount of the load 14 which is operating according to the user's request, and the like. .. The details of the method of increasing the power consumption of the load 14 from the normal amount will be described later.

As described above, in the power control method according to the embodiment, when the excessive power generation of the MG 12 is detected, the power consumption of the load 14 is intentionally increased, so that the charge amount of the LiB 15 and the power consumption of the load 14 are usually increased. You can consume the excess that cannot be consumed by the amount.

Therefore, according to the power control method according to the embodiment, since the excess power generation can be eliminated by consuming the excess amount, the inside of the MG 12 does not become overvoltage or overcurrent. That is, according to the power control method according to the embodiment, it is possible to suppress the occurrence of system abnormalities due to excessive power generation.

Next, the configuration of the power control device 1 according to the embodiment will be described with reference to FIG. FIG. 2 is a block diagram showing a configuration of the power control device 1 according to the embodiment. As shown in FIG. 2, the power control device 1 is connected to the MG 12, the DCDC converter 13, the load 14, and the LiB 15.

Further, the power control device 1 includes a control unit 2 and a storage unit 3. The control unit 2 includes an acquisition unit 21, a detection unit 22, a cutoff unit 23, and a load control unit 24. The storage unit 3 stores each information necessary for the control of the control unit 2, information generated by the control unit 2, and the like.

Here, the power control device 1 includes, for example, a computer having a CPU (Central Processing Unit), a ROM (Read Only Memory), a RAM (Random Access Memory), a data flash, an input / output port, and various circuits.

The CPU of the computer functions as the acquisition unit 21, the detection unit 22, the blocking unit 23, and the load control unit 24 of the control unit 2, for example, by reading and executing the program stored in the ROM.

Further, at least one or all of the acquisition unit 21, the detection unit 22, the cutoff unit 23, and the load control unit 24 of the control unit 2 are hardware such as an ASIC (Application Specific Integrated Circuit) and an FPGA (Field Programmable Gate Array). It can also be configured with.

Further, the storage unit 3 corresponds to, for example, a RAM or a data flash. The RAM and the data flash can store information of various programs and the like. The power control device 1 may acquire the above-mentioned program and various information via another computer or a portable recording medium connected by a wired or wireless network.

Next, each function of the control unit 2 (acquisition unit 21, detection unit 22, blocking unit 23, and load control unit 24) will be described.

The acquisition unit 21 acquires various types of information. For example, the acquisition unit 21 acquires the power generation amount information regarding the power generation amount from the MG 12, the charge amount information regarding the charge amount from the LiB15, and the power consumption information regarding the power consumption from the load 14. The acquisition unit 21 outputs the acquired power generation amount information, charge amount information, and power consumption information to the detection unit 22.

In addition, the acquisition unit 21 acquires the stored amount information indicating the current stored amount from the LiB15. The acquisition unit 21 outputs the acquired storage amount information to the cutoff unit 23.

The detection unit 22 detects the excess power generation of the MG12 generator. For example, the detection unit 22 detects excess power generation based on the power generation amount information, the charge amount information, and the power consumption information acquired from the acquisition unit 21.

Specifically, the detection unit 22 detects excess power generation when the power generation amount of MG 12 exceeds the total value of the charge amount of LiB15 and the power consumption of the load 14. When the detection unit 22 detects the excess power generation, the detection unit 22 notifies the cutoff unit 23 and the load control unit 24 that the excess power generation has been detected.

The blocking unit 23 controls the on / off of the relay R provided in the electric path between the MG 12 and the LiB 15. Specifically, when the detection unit 22 detects excessive power generation and the storage amount of LiB15 is equal to or higher than a predetermined threshold value, the cutoff unit 23 turns off the relay R to turn off the electric path between MG12 and LiB15. To shut off. This point will be described with reference to FIG.

FIG. 3 is a diagram showing a blocking process by the blocking unit 23. In FIG. 3, it is assumed that the stored amount of LiB15 is equal to or higher than a predetermined threshold value TH at the time of excessive power generation of MG12.

When the overpower generation of MG12 is detected and the amount of electricity stored in LiB15 is equal to or higher than a predetermined threshold value TH, the cutoff unit 23 outputs an off instruction to turn off the relay R to cut off the electric path between MG12 and LiB15.

On the other hand, the cutoff unit 23 keeps the relay R on when the stored amount of LiB15 is less than the predetermined threshold value TH. As a result, it is possible to prevent the LiB15 from being overcharged by cutting off the electric circuit when it is near full charge while charging with the electric power at the time of overcharge. Therefore, it is possible to reduce LiB failure due to overcharging and deterioration of battery performance.

Returning to FIG. 2, the load control unit 24 will be described. When the detection unit 22 detects the excessive power generation of the MG 12, the load control unit 24 controls to increase the power consumption of the load 14 more than the normal amount.

Specifically, there are the following two methods for increasing the power consumption of the load 14 from the normal amount.
(1) Newly operate the load 14 that is not currently operating (2) Increase the current operating amount of the load 14 that is operating according to the user's request.

<(1) Operate the load 14 that is not currently operating>
The load control unit 24 newly operates a load 14 that alerts the occupants of the vehicle and the surroundings, for example. Specifically, the load control unit 24 increases the power consumption of the load 14 by displaying a warning light in the instrument panel, sounding a horn, turning on a light, and turning on an interior light. ..

That is, the load control unit 24 increases the power consumption of the load 14 for notifying the occupants of the vehicle or the surroundings of the vehicle of predetermined information. As a result, it is possible to inform the occupants of the vehicle and the surroundings that excessive power generation is occurring.

In addition, the load control unit 24 increases the power consumption of the load 14 related to the comfort of the vehicle interior. Specifically, the load control unit 24 controls to cool the refrigerant of the air conditioner that is not operating. As a result, for example, the refrigerant can be cooled in advance before the occupant operates the air conditioner, so that cold air can be sent into the vehicle interior immediately after the operation. That is, the comfort of the vehicle interior can be improved.

<(2) Increase the current operating amount of the load 14 operating according to the user's request>
The load control unit 24, for example, makes the lit light brighter than the normal state, increases the volume of the horn during output, and raises the backlight brightness of the display such as navigation. That is, the load control unit 24 increases the operating amount of the load 14 more than usual when the load 14 for notifying the occupants of the vehicle and the surroundings of predetermined information is in operation. As a result, it is possible to more reliably convey attention to the occupants of the vehicle and the surroundings.

Further, for example, when the wiper is the operation name, the load control unit 24 increases the operation speed (operation interval) of the wiper, increases the air volume of the air conditioner, or blows the wind of the air conditioner to the windshield. Control may be performed to eliminate (or prevent) fogging. That is, the load control unit 24 may increase the amount of operation of the load 14 related to the comfort of the vehicle interior more than usual.

Further, the load control unit 24 discards the excess power when there is no load 14 to be controlled as described above, that is, when the excess power generation of the MG 12 is detected and there is no load 14 capable of increasing the power consumption. To do.

For example, when the refrigerant of the air conditioner has been cooled in advance by using the excess electric power as described above, the load control unit 24 reheats the cooled refrigerant and returns it to the original uncooled refrigerant. That is, by cooling the refrigerant of the air conditioner and then warming it and returning it to the uncooled refrigerant, it is possible to prevent the state of the load 14 from changing even though the excess electric power is used (that is, the electric power is discarded). It can be in a state equivalent to that).

Alternatively, the load control unit 24 may connect the electric line from the MG 12 to the ground by switching the relay, for example, so that the excess power flows to the ground and dispose of it.

Next, the procedure of the process executed by the power control device 1 according to the embodiment will be described with reference to FIG. FIG. 4 is a flowchart showing a procedure of processing executed by the power control device 1 according to the embodiment.

As shown in FIG. 4, first, the acquisition unit 21 acquires information for detecting excess power generation (step S101). Specifically, the acquisition unit 21 acquires power generation amount information from MG12, charge amount information from LiB15, and power consumption information from load 14.

Subsequently, the detection unit 22 determines whether or not the excess power generation of the MG 12 has been detected based on the information acquired by the acquisition unit 21 (step S102).

When the detection unit 22 detects the excessive power generation of the MG 12 (step S102: Yes), the acquisition unit 21 acquires the storage amount information indicating the storage amount of the LiB15 (step S103).

Subsequently, the blocking unit 23 determines whether or not the stored amount of LiB15 is equal to or higher than a predetermined threshold value (step S104).

When the amount of electricity stored in LiB15 is equal to or higher than a predetermined threshold value (step S104: Yes), the blocking unit 23 cuts off the relay R provided in the electric path between MG12 and LiB15. (Step S105).

Subsequently, the load control unit 24 controls to increase the power consumption of the load 14 from the normal amount (step S106).

Subsequently, the load control unit 24 determines whether or not there is no load 14 that increases power consumption and there is still excess power (step S107).

When there is excess power (step S107: Yes), the load control unit 24 controls to discard the excess power (step S108), and ends the process.

On the other hand, in step S102, when the excessive power generation of MG 12 is not detected (step S102: No), the load control unit 24 controls the power consumption of the load 14 with a normal amount (step S109), and ends the process.

Further, in step S104, the blocking unit 23 executes step S103 when the amount of electricity stored in LiB15 is less than the threshold value (step S104: No).

Further, in step S107, the load control unit 24 ends the process when there is no excess power (step S107: No).

As described above, the power control device 1 according to the embodiment includes a detection unit 22 and a load control unit 24. The detection unit 22 detects the excess power generation of the generator (MG12) that supplies the electric power generated by the operation of the internal combustion engine (engine 10) to the storage battery (LiB15) and the load 14. When the detection unit 22 detects excessive power generation, the load control unit 24 controls to increase the power consumption of the load 14 more than a normal amount. As a result, it is possible to suppress the occurrence of an abnormality in the power generation system S due to excessive power generation.

Further effects and variations can be easily derived by those skilled in the art. For this reason, the broader aspects of the invention are not limited to the particular details and representative embodiments expressed and described as described above. Therefore, various modifications can be made without departing from the spirit or scope of the general concept of the invention as defined by the appended claims and their equivalents.

1 Power control device 2 Control unit 3 Storage unit 10 Engine 11 Power transmission mechanism 13 DCDC converter 14 Load 21 Acquisition unit 22 Detection unit 23 Blocking unit 24 Load control unit R Relay S Power generation system

Claims (6)

A detector that detects the excess power generation of the generator that supplies the power generated by the operation of the internal combustion engine to the storage battery and load, and
A power control device including a load control unit that controls to increase the power consumption of the load more than a normal amount when the excess power generation is detected by the detection unit. When the excess power generation is detected by the detection unit and the amount of electricity stored in the storage battery is equal to or greater than a predetermined threshold value, the detection unit further includes a blocking unit that cuts off the electric circuit between the generator and the storage battery. The power control device according to claim 1. The load control unit
The power control device according to claim 1 or 2, wherein the power consumption of a load for notifying a vehicle occupant or a vehicle's surroundings of predetermined information is increased. The load control unit
The power control device according to any one of claims 1 to 3, wherein the power consumption of a load related to the comfort of a vehicle interior is increased. The load control unit
The power control device according to any one of claims 1 to 4, wherein when the overpower generation is detected by the detection unit and there is no load capable of increasing power consumption, the power is discarded. .. A detection process that detects excessive power generation by a generator that supplies the power generated by the operation of the internal combustion engine to the storage battery and load.
A power control method comprising: a load control step of controlling to increase the power consumption of the load more than a normal amount when the excess power generation is detected by the detection step.

Images