saviour stivala wrote: ↑26 May 2023, 12:06
There is no need for any rule outlawing recovery by MGU-K while under power, this as the present MGU-K recovery guidelines outlines/defines recovery by MGU-K ''energy recovered as under braking that would otherwise have gone to waste''. This eliminates design possibilities of MGU-K switching to recovery mode under throttle, and further as explained, the possibility of driver using both brake and throttle together so as MGU-K goes into recovery mode is eliminated by the brake-by-wire fail safe system.
2022 Power Unit regulations:
5.1 Definitions
5.1.5 Energy Recovery System (ERS)
A system that is designed to recover energy from the car, store that energy and make it available to propel the car and, optionally, to drive any ancillaries and actuation systems necessary for its proper function.
5.1.6 Motor Generator Unit - Kinetic (MGU-K)
The Kinetic Motor Generator Unit is the electrical machine mechanically linked to the drive train as part of the ERS.
5.3 Other Means of Propulsion and Energy Recovery
5.3.3 The MGU-K must be solely and permanently mechanically linked to the powertrain before the main clutch. This mechanical link must be of fixed speed ratio to the engine crankshaft. An in-line, passive, dissipative energy torque limitation device may be incorporated in this link which temporarily allows the speed ratio to change for the sole purpose of protecting the components from dynamic torque overshoots. This device may only act above 220Nm when referred to crankshaft speed.
The rotational speed of the MGU-K may not exceed 50,000rpm.
The mass of the MGU-K (as defined in line 12 of Appendix 3 to these regulations) may not be less than 7kg.
The power of the MGU-K may not exceed 120 kW. The maximum torque of the MGU-K may not exceed 200Nm. The torque will be referenced to the crankshaft speed and the fixed efficiency correction defined in Article 5.3.2 will be used to monitor the maximum MGU-K power and torque.
The laminate thickness of the MGU-K may not be less than 0.05mm.
The MGU-K must be fitted with a torque sensor which has been manufactured and calibrated by a FIA designated supplier to a specification determined by the FIA. The installation of the MGU-K torque sensor must be approved by the FIA.
5.6 Power unit torque demand
5.6.1 The only means by which the driver may control acceleration torque to the driven wheels is via a single foot (accelerator) pedal mounted inside the survival cell.
5.6.2 Designs which allow specific points along the accelerator pedal travel range to be identified by the driver or assist him to hold a position are not permitted.
5.6.3 At any given engine speed the driver torque demand map must be monotonically increasing for an increase in accelerator pedal position.
5.6.4 At any given accelerator pedal position and above 4,000rpm, the driver torque demand map must not have a gradient of less than – (minus) 0.045Nm/rpm.
5.13 Energy Recovery System (ERS)
5.13.1 The system will be considered shut down when no high voltage can be present on any external or accessible part of the ERS, or across any capacitor belonging to the MGU control units.
The shutdown process must take no longer than two seconds from activation.
It must be possible to shut down the ERS via the following means :
a. The switch required by Article 8.8.1.
b. The switches required by Article 8.8.2.
c. The switch or button required by Article 9.4.
5.13.2 The ERS must shut down when the FIA Standard ECU initiates an anti-stall engine shut off.
5.13.3 All cars must be fitted with two ERS status lights which:
a. Have been supplied by an FIA designated manufacturer and fitted to the car in accordance with the instructions in the Appendix to the Technical and Sporting Regulations.
b. Are in working order throughout the Competition even if the main hydraulic, pneumatic or electrical systems on the car have failed.
c. Remain powered for at least 15 minutes if the car comes to rest with its engine stopped.
d. Are marked with a “HIGH VOLTAGE” symbol according to ISO3864 of at least 30mm along the triangle side and no more than 50mm away from the lights.
5.13.4 All cars must provide signals regarding the car operating and insulation states to the FIA ADR in order to facilitate control of the ERS status lights.
5.13.5 The maximum working voltage on the car must never exceed 1000V.
5.13.6 The following elements of the power unit must be installed wholly within the survival cell:
a. ES elements as defined in lines 16 and 17 of Appendix 3 to these regulations.
b. Any DC-DC converter connected to ES HV DC bus. Includes active parts, enclosure, brackets and supports.
c. CU-K. Includes active parts, enclosure, brackets and supports.
d. CU-H. Includes active parts, enclosure, brackets and supports.
e. HV DC connections between ES and CU-K/CU-H/DC-DC converter. Includes all conductors, insulation, EMC screening, mechanical and thermal shielding.
The minimum values of volume and mass for these groups of components are 22.0 l and 31.0 kg respectively. The procedure which will be used to determine these values may be found in the Appendix to the Technical and Sporting Regulations.
I can't see anything like "'energy recovered as under braking that would otherwise have gone to waste".
The regulations only use the word "waste" in referring to "wastegate" and to a part of the fuel specifications:
16.2 Fuel definitions
Second generation bio components
"Second generation bio components are components manufactured from various types of non-food biomass, including lignocellulosic biomass, algae, agricultural residues or waste and dedicated non-food energy crops grown on marginal land unsuitable for food production. Biocomponents from food crops can be regarded as second generation only if they have already fulfilled their food purpose (e.g. waste vegetable oil because it has already been used and is no longer fit for human consumption). It includes all biocomponents falling into the RED II definition."
Perhaps you could point out where in the regulations using the MGUK to recover energy while at full throttle is forbidden, or where it states the MGUK can only recover energy under braking.
