JP2014189173A - Hybrid electrically-driven vehicle - Google Patents

Abstract

A hybrid electric vehicle capable of preventing damage due to overdischarge of a battery in a hybrid electric vehicle in which a part of driving force generated by an engine can be replaced by a travel motor using a replaceable battery as a power source. provide.
When a control means 10 detects that a measured value of an internal resistance detector 11 connected to a replaceable battery 7 exceeds a predetermined threshold value, the control means 10 determines that the battery 7 has deteriorated and travels. Substitution of the driving force of the diesel engine 4 by the motor 5 is stopped, and control for charging the deteriorated battery 7 is performed.
[Selection] Figure 1

Description

  The present invention relates to a hybrid electric vehicle, and more particularly, in a hybrid electric vehicle in which a part of driving force generated by an engine can be replaced by a travel motor using a replaceable battery as a power source, to prevent damage due to overdischarge of the battery. It is related with the hybrid electric vehicle which can do.

  A hybrid electric vehicle (hereinafter referred to as “HEV”) is a type that generates a driving force by combining an engine and a traveling motor mounted on the vehicle (parallel HEV), while a driving force is generated only from the traveling motor. The engine can be broadly classified into a type (series HEV) that is directly connected to a generator and only supplies power to the traveling motor (see, for example, Patent Document 1).

  In any HEV, surplus energy during normal traveling of the vehicle and regenerative energy during braking are collected and stored as electric power in a battery that is a power source of the traveling motor.

  Among the former parallel HEVs, there is a type in which the driving force of the vehicle is generated mainly from the engine for the purpose of reducing the size and weight of the traveling motor and battery, and the traveling motor is used only for assisting the engine. . In this type of parallel HEV, when the battery performance deteriorates, the assist of the engine by the traveling motor is stopped until the battery is replaced.

  However, if the period until battery replacement is prolonged, the battery may be overdischarged due to a self-discharge phenomenon, which may lead to damage such as liquid leakage.

JP 2002-238105 A

  An object of the present invention is a hybrid electric vehicle that can prevent damage due to overdischarge of a battery in a hybrid electric vehicle in which a part of driving force generated by an engine can be replaced by a traveling motor that uses a replaceable battery as a power source. It is to provide an electric vehicle.

  The hybrid electric vehicle of the present invention that achieves the above object includes an engine and a travel motor that uses a replaceable battery as a power source, and a part of the driving force generated by the engine can be replaced by the travel motor. In the hybrid electric vehicle, the hybrid electric vehicle includes a measuring unit that measures an internal resistance of the battery, and a control unit, and the control unit is configured such that the measured value of the measuring unit exceeds a predetermined value. Is characterized in that it determines that the battery has deteriorated, stops the substitution of the driving force by the travel motor, and performs control for charging the deteriorated battery.

  In the above hybrid electric vehicle, it is desirable to charge the battery up to the rated maximum capacity in order to maximize the time until the battery is overdischarged.

  In addition, when it is determined that the battery has deteriorated, the warning means that prompts the replacement of the battery is activated, so that the battery can be replaced at an early stage to prevent damage due to overdischarge.

  According to the hybrid electric vehicle of the present invention, when the internal resistance of the battery exceeds a predetermined threshold value, the substitution of the driving force by the travel motor is stopped and the control for charging the battery is performed. Since the time until the battery is overdischarged due to the self-discharge phenomenon is extended, the battery can be prevented from being damaged due to overdischarge.

1 is a configuration diagram of a hybrid electric vehicle according to an embodiment of the present invention.

  Embodiments of the present invention will be described below with reference to the drawings.

  FIG. 1 shows a configuration of a hybrid electric vehicle according to an embodiment of the present invention.

  This hybrid electric vehicle (hereinafter referred to as “HEV”) includes a diesel engine 4 and a travel motor 5 that are connected to an output shaft 2 that transmits a driving force to a pair of left and right drive wheels 1 and 1 via a transmission 3. The travel motor 5 is provided with a replaceable battery 7 that is electrically connected through an inverter 6. Further, between the transmission 3 and the diesel engine 4, a wet multi-plate clutch 8 and the like for connecting and disconnecting the driving force are provided.

  The driving force generated by the diesel engine 4 is controlled by the ECU 9 in accordance with the running state of the HEV. Further, the supply of electric power between the traveling motor 5 and the battery 7 is controlled via the inverter 6 by the control means 10 that has received a command from the ECU 9.

  Between the battery 7 and the inverter 6, there is provided an internal resistance detector 11 that is a measuring means for measuring the internal resistance of the battery 7 from the current value inputted to and outputted from the battery 7. The measured value of the internal resistance detector 11 is monitored regularly or continuously by the control means 10 through a signal line (dotted line). The battery 7 is usually composed of a lithium ion battery. In the present embodiment, the ECU 9 and the control unit 10 are separated from each other, but the function of the control unit 10 can be assigned to the ECU 9.

  The HEV basically starts and travels by the driving force generated by the diesel engine 4, but the driving motor 5 assists the driving force in accordance with the load applied to the output shaft 2. Further, surplus energy during normal driving of the HEV and regenerative energy during braking are recovered by using the traveling motor 5 as a generator, and the battery 7 is charged through the inverter 6.

  When the control means 10 detects that the measured value of the internal resistance detector 11 exceeds a predetermined threshold value, the control means 10 determines that the battery 7 has deteriorated and travels through the inverter 6. The assist of the driving force by the motor 5 is stopped. This threshold value is determined in advance according to the specifications of the battery 7. For example, in the case of the battery 7 made of a lithium ion battery for ordinary automobiles, the threshold value is about 400 to 500 mΩ.

  Furthermore, the control means 10 stops the assist of the traveling motor 5 and at the same time activates the warning means 12 that prompts replacement of the battery 7 through the signal line. The warning means 12 is not particularly limited, and examples thereof include warning lights and alarm devices installed on the driver's seat display panel.

  In such HEV, when it is determined that the battery 7 has deteriorated due to an increase in internal resistance, the control means 10 controls the inverter 6 to charge the battery 7.

  By doing so, since the time until the battery 7 is overdischarged due to the self-discharge phenomenon is extended, the battery 7 is prevented from being damaged due to overdischarge even if the period until the replacement of the battery 7 is prolonged. can do.

  It is desirable to charge the battery 7 up to the rated maximum capacity of the battery 7. By doing so, it is possible to maximize the time until the battery 7 is overdischarged due to the self-discharge phenomenon. The rated maximum capacity of the battery 7 is a value defined in advance according to the specifications of the battery 7, and is a state in which, for example, the storage rate (SOC) of the battery 7 is 70 to 90%.

DESCRIPTION OF SYMBOLS 1 Drive wheel 2 Output shaft 3 Transmission 4 Diesel engine 5 Traveling motor 6 Inverter 7 Battery 8 Wet multi-plate clutch 9 ECU
10 Control means 11 Internal resistance detector 12 Warning means

Claims (3)

In a hybrid electric vehicle that includes an engine and a travel motor that uses a replaceable battery as a power source, and the travel motor can replace a part of the driving force generated by the engine,
The hybrid electric vehicle includes measurement means for measuring the internal resistance of the battery, and control means.
When the measured value of the measuring means exceeds a predetermined value, the control means determines that the battery has deteriorated, stops substitution of the driving force by the travel motor, and the deteriorated battery A hybrid electric vehicle characterized by performing control for charging the vehicle.   The hybrid electric vehicle according to claim 1, wherein the control unit charges the deteriorated battery to a rated maximum capacity of the battery.   The hybrid electric vehicle according to claim 1 or 2, further comprising warning means for prompting replacement of the battery, wherein the control means activates the warning means when it is determined that the battery has deteriorated.

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