2014 - Mazda6 - I-ELOOP

i-ELOOP [i-ELOOP]

Outline

• For improved fuel economy, electrical power is generated using kinetic energy during deceleration and retrieved as electrical energy, which decreases the amount of fuel used for supplying power.

• i-ELOOP is a Mazda-unique regenerative braking system^* that generates and stores electrical energy during deceleration. Through efficient energy regeneration, storage, and usage, fuel economy improvement is achieved while driving.

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The regenerative braking system is a mechanism for converting kinetic energy during deceleration to electrical energy and storing it for reuse. The electricity stored from the regenerative braking is re-used as power for electrical devices such as the A/C and audio, which decreases the fuel consumption amount required by the engine to supply power.

Structural View

• i-ELOOP consists mainly of the following parts.

System Wiring Diagram

Operation

• The operation aspect of i-ELOOP is as follows.

  

• The i-ELOOP operation mode varies depending on the vehicle driving conditions and the conditions of i-ELOOP-related parts.

1. Regenerative braking mode

Purpose

• During deceleration, fuel economy is improved by the generator producing electricity.

Operation condition

• During fuel-cut by release of accelerator pedal and TCC engagement

Operation content

• Generator operates at full capacity and stores electricity in the Capacitor (i-ELOOP). The voltage stored in the Capacitor (i-ELOOP) is lowered by the DC-DC converter and electrical power is supplied to the vehicle electrical devices.

2. Conventional power generation mode (no regenerative braking)

Purpose

• During constant/acceleration travel, battery stability is maintained by the power generated by the generator.

Operation condition

• During engine rotation, battery voltage is certain value or less

Operation content

• Generator operates and 12 to 25 V of electrical power is stored in the Capacitor (i-ELOOP). The voltage stored in the Capacitor (i-ELOOP) is lowered by the DC-DC converter and electrical power is supplied to the vehicle electrical devices. (Compared to regenerative braking mode, amount of power generated by generator is low.)

3. Capacitor (i-ELOOP) power supply mode

Purpose

• Electrical power is supplied to vehicle electrical devices from the Capacitor (i-ELOOP).

Operation condition

• Capacitor (i-ELOOP) voltage exceeds battery voltage.

Operation content

• The voltage stored in the Capacitor (i-ELOOP) is lowered by the DC-DC converter and electrical power is supplied to vehicle electrical devices.

4. Battery power supply mode

Purpose

• Electrical power is supplied to vehicle electrical devices from the battery.

Operation condition

• Capacitor (i-ELOOP) voltage certain value or less, or during cranking.

Operation content

• The same as on contemporary vehicles, electrical power is supplied to vehicle electrical devices from the battery.

5. By-pass mode

NOTE:

• During by-pass mode, verification is not possible using the instrument cluster indication.

• If high-capacity audio or additional electrical devices are connected, the by-pass mode may operate frequently due to the increase in the vehicle electrical load.

Purpose

• If vehicle electrical load (consumption current) exceeds 50A or more, a bypass relay within the DC-DC converter is energized to supply power generated by the generator directly to the vehicle electrical devices.

Operation condition

• Bypass mode is operating due to the following conditions:

• Vehicle electric load (current consumption) is 50 A or more

• Voltage reduction circuit in DC-DC converter is malfunctioning

• Ambient temperature is less than 0 °C {32 °F}

• Battery charge condition is less than 65%

Operation content

• Turns the bypass relay in the DC-DC converter on and the power generated by the generator is also supplied directly to the vehicle’s electrical devices.At this time, the amount of power generated by the generator is suppressed so that power can be supplied directly to the vehicle’s electrical devices.

6. Pre-charge mode

NOTE:

• If the Capacitor (i-ELOOP) continues to self-discharge (vehicle left for long periods with engine not started)/excess back-up current consumption, the pre-charge mode may operate due to the decrease in Capacitor (i-ELOOP) voltage.

• If the vehicle is jump started, leave the jumper connected until the warning message is no longer displayed.

• If vehicle is driven while the warning is displayed, a warning sound will be heard and power steering assist will be limited.

Purpose

• The Capacitor (i-ELOOP) charges for the following two reasons.

• If the Capacitor (i-ELOOP) voltage is low, the excitation current to the generator lowers and the generator may not be able to generate power.

• To supply power to the battery from the Capacitor (i-ELOOP), a higher electrical load than the battery is required.

Operation condition

• If the Capacitor (i-ELOOP) voltage is a certain value or less (stops operation when Capacitor (i-ELOOP) voltage reaches certain value or more.)

Operation content

• Depending on each type of condition, the method for charging the Capacitor (i-ELOOP) varies.

• The PCM sends a message display request signal to the instrument cluster during Capacitor (i-ELOOP) pre-charge when the engine is started.

• If the vehicle is driven while a message is displayed in the LCD, the PCM sends an i-ELOOP warning alarm sound to the instrument cluster.

• For details on the i-ELOOP warning alarm, refer to i-ELOOP warning alarm. (See i-ELOOP WARNING ALARM [i-ELOOP].)

• A message display request signal is sent for a maximum of 3 min and if the message display request condition continues for 3 minutes or more, the PCM sends a master warning light request and message display request to the instrument cluster.

7. Capacitor (i-ELOOP) power generation mode

Purpose

• Surplus power stored in the Capacitor (i-ELOOP) charges the battery.

Operation condition

• With ignition switched off and hood closed, Capacitor (i-ELOOP) voltage is certain voltage or more.

Operation content

• During normal operation, extra voltage from the capacitor is used to charge the battery. If the battery voltage is high and power cannot be supplied from the capacitor to the battery, capacitor voltage flows to the ground side.

Normal operation

When power cannot be supplied to battery

• The following are examples of the i-ELOOP operation in each mode.

  

Instrument cluster display

• The PCM sends a regenerative braking condition/regenerative power amount/Capacitor (i-ELOOP) accumulation amount from i-ELOOP to the instrument cluster.

• The instrument cluster displays information related to i-ELOOP in the LCD by the signal received from the PCM.

• The instrument cluster display can be changed using the personalization feature.

Regenerative braking power generation condition gauge

• Informs the user of the i-ELOOP operation status.

Regenerative braking power generation amount gauge

• Displays the amount of electrical power generated by regenerative braking.

Capacitor (i-ELOOP) accumulation amount gauge

• Displays the amount of electrical power stored in the Capacitor (i-ELOOP).

i-ELOOP malfunction indication

• If a malfunction occurs in an i-ELOOP-related part, the PCM sends a master warning light illumination request and a message display request in the LCD to the instrument cluster.

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