Explanation Of Circuits

WARNING: This page is about a different variant/trim than selected.

The brake override system performs control to restrain the driving torque, when the accelerator pedal and brake pedal are depressed during driving. Control operating conditions and control items are shown below.

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Control operating condition

When the accelerator pedal and brake pedal are depressed
NOTE: Control may not be operated depending on the relationship between the accelerator pedal opening angle and speed.

Control items
Restraining of driving torque
NOTE:
- During the control operation, the torque requested by the accelerator pedal operation is restrained based on the amount of the brake pedal stroke.
- When the driving torque is maximally restrained with the brake pedal strongly depressed together with accelerator pedal, the operation indicator is displayed on the meter. (The displayed operation indicator allows to visually confirm that the system is operating.)
Recovery conditions
When the accelerator pedal or the brake pedal is returned

Normal Mode
In Normal Mode, switch-over of EV traveling and hybrid traveling is performed automatically according to the change of charge amount for the high voltage battery.
- When the charge amount for the high voltage battery is large, EV traveling is actively performed. However, at high load or high vehicle speed, the engine operates automatically.
- When the charge amount for the high voltage battery low, the hybrid traveling that uses the engine and motor concurrently is performed. However, if the charge amount recovers by regeneration, etc., the EV traveling is performed again.
Hybrid battery save mode
In the hybrid battery save mode, the vehicle uses the hybrid traveling actively so as not to reduce the power charged in the high voltage battery. This allows the vehicle to maintain the charged power in such a case of performing the EV traveling at destinations.
- Even when the charge amount of the high voltage battery is high, the charged power can be maintained by restraining the EV traveling and performing the hybrid traveling.
Hybrid battery charge mode
In the hybrid battery charge mode, the high voltage battery is actively charged while the vehicle is being driven. This allows to charge the battery by using the engine driving force to generate power also without depending on external charging in such a case as performing EV traveling at destinations.
- By increasing the engine load during driving, the high voltage battery is charged.
- When the high voltage battery is charged sufficiently, the mode is automatically switched to the hybrid battery save mode.

The drive start control is controlled by Hybrid vehicle control ECU assembly.

When it is judged that the accelerator pedal and shift are operated differently from usual, the driving torque is restrained and operation notice is indicated on the combination meter as necessary.

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With IG ON, Hybrid vehicle control ECU assembly provides the current to MREL terminal to turn IGCT scene relay ON. Thus, power is supplied to +B1 and +B2 terminals.

The resolver is a sensor that detects the magnetic pole position of the motor rotor. Grasping the magnetic pole position is essential in order to control the motor correctly. The resolver has a built-in stator with a magnetizing coil and two detection coils (S and C) attached. Because the rotor is oval, the gap between the stator and rotor changes as the rotor rotates. Alternating current of a constant frequency flows in the magnetizing coil, and the alternating current is output from the detection coils (S and C) according to the sensor rotor position.

Motor generator control ECU incorporated in Inverter with converter assembly detects the absolute position of the rotor based on the waveform phase and waveform height of the detection coils (S and C). Also, it is used as a speed sensor by calculating the amount of position change by CPU within a predetermined period of time.

Motor generator control ECU incorporated in Inverter with converter assembly monitors the output signals of Motor resolver and detects abnormal.

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The malfunction cause may be the high voltage system of the motor.

Check the motor internal resistance and connecting condition of the high voltage wires from the inverter to motor in order to check for open and short circuit.

The resolver is a sensor that detects the magnetic pole position of the generator rotor. Grasping the magnetic pole position is essential in order to control the generator correctly. The resolver has a built-in stator with a magnetizing coil and two detection coils (S and C) attached. Because the rotor is oval, the gap between the stator and rotor changes as the rotor rotates. Alternating current of a constant frequency flows in the magnetizing coil, and the alternating current is output from the detection coils (S and C) according to the sensor rotor position.

Motor generator control ECU incorporated in Inverter with converter assembly monitors the output signals of Generator resolver and detects abnormal.

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The malfunction cause may be GENERATOR HIGH-VOLTAGE CIRCUIT.

Check the generator internal resistance and connecting condition of the high voltage wires from the inverter to generator in order to check for open and short circuit.

Shutdown power supply to the motor by the shutdown signal from Hybrid vehicle control ECU assembly to Motor generator control ECU.

High voltage of HV battery is supplied to the inverter via the system main relay operation.

The inverter produces heat during the process of converting high voltage DC for HV battery to alternating current for the motor/generator. Therefore, the inverter is cooled by the special cooling system consisting of Inverter water pump, fan and radiator. This cooling system is independent from the engine cooling system. Hybrid vehicle control ECU assembly monitors Inverter water pump, fan and cooling system, and detects malfunctions.

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