Project: Building the Best Controller

Kingfish

100 MW
Joined
Feb 3, 2010
Messages
4,064
Location
Redmond, WA-USA, Earth, Sol, Orion–Cygnus Arm, Mil
Project Description & Status
Working Acronym: BBC
Date Launched: Proposed on Monday August 16th, 2010
Stakeholders: tbd
Current Feature Spec Version: 0.1.3

Project Description: Resolved, to create a three-part modular designed EV controller that is feature-robust, reliable, extensible, and open-sourced. The three modules are defined as Main Power Supply, Controller/Brain, and Driver/FET Circuit.

Goal: Proposed that we craft and assemble no less than 10 working units of Version 1 before EOY 2010.

Current Status: Accepting feature requests germane to the topic until Wednesday August 25th, after which teams will organize to bring the nascent challenge to fruition. In human terms: We are Newborn.

Notes: This is a live project and we expect changes and updates on a daily basis. Please check the active threads for more detailed information.

Active Threads:
Revision History: Date|Version|Description
2010.08.16|0.1.0| Proposed.
2010.08.18|0.1.1| Addendums to date.
2010.09.06|0.1.2| Began appending details. Added Common Interface and Software sections.
2010.11.18|0.1.3| MPS spec is locked down enough to consider development with Driver/FET features firming up well.


Directory:
Project Description & Status (this section)
Feature Specification
System Components & Classification
Block Diagrams
MPS – Main Power Supply
Driver/FET
MCU - Microcontroller
PCB Module Common Interface
Software
reserved 0
reserved 1

Thank you for your support!
Please direct comments to the active threads or to Kingfish.
 
This is the master Feature Quick-Specification for the BBC. The information presented here is as a working proposal, a Request for functionality, and is subject to change daily until it is locked down for development.

There are three modules, each designed to be a separate printed circuit board.

Main Power Supply:
  • Input from Battery Power, 36V to >100V, with voltage test pads
    • Q: For scoping, what is the upper limit for V & I?
    • Option to have high-charge/discharge buffer (SuperCap or Hi-C batteries) in close proximity or mounted directly on pcb.
  • 12-15V Primary Regulated PS (likely switched); this is the Main System Bus.
    • Controller/Brain PS, regulated (5V or less)
    • On/Off circuitry (cut power to Brain or Driver supply), with slow-ramp/spark suppression to extend switch life.
    • Provision Auxiliary Power for lights and accessories (may be a mix of 3.3, 4.1, 9V), possibly regulated, with optional capacitance when main power is lost. Example: Headlights still work for another hour if the main batteries loose power and you have to pedal home in the dark.
    • Optionally provision Relay Power for Delta/Wye components.
    • Scalable power output and robust trace layout to meet/exceed need.
  • Separate Charger & BMS connections/interface

Driver Circuit/FETs:
  • Direct link to Battery Bus; Location of this circuit needs to be close to the Battery for best performance
  • Power Source Isolation and quality is paramount
  • Regulated, Optically-Isolated?, 12Vor 15V? for FETS
  • Modular driving circuit to provide fast-switching/high-resolution and high-current requirements
  • Synchronous rectification
  • Manage Regeneration
  • Audibly/RF-quiet; supports either Trapezoidal or Sinusoidal waveforms
  • Supports low-to-high kV
  • PCB designed to handle 40-50A minimum out of the box, with built-in options to dramatically scale-up.
  • Flexible thermal cooling options
  • Scalable design!
  • Direct Link to associated MCU

MCU: Controller Module:
  • Low Voltage, low power demand
  • Manage low-to-high kV motors
  • Audibly quiet
  • Basic Features:
    • Throttle; ramp, resolution, delay, dual-throttle support, analog, digital
    • ebrake-Regen; minimum, maximum, resolution, dual-input support, variable, analog, digital
    • Multi-speed switching on the fly (ala 3-way)
    • Smart-Cruise; on/off, set, coast, accel/decel, one-to-many presets stored in non-volatile memory.
    • Alarm/Wheel-locking; user-configurable actions, supports various responses, including phone home
    • Reverse
    • Fully Support CA
  • Advanced Features:
    • Waveform: Trapezoidal, Sinusoidal, or possibly custom profile
    • Power Management profiles for hills and flats
    • Advanced Throttling; by current-limiting, by voltage-limiting, by phase-shifting/clocking, other?
    • Multi-motor on same drive-train support (R/C)
    • Multi-motor on multi-axis support, non-collision – or support Master-Slave/chaining for XWD systems
    • Electronic Transmission; Support Delta/Wye signal-switching
    • Auto-Configuration/Setup Wizard:
      • Sensor-Sensorless
      • Phase wiring
      • Set poles and slots
      • Core/Coreless
      • limits for V/I
  • Store multiple Battery Configurations (Commuting/Touring/Mountain-King/Race-Day)
  • System Health-Reporting
    • Event Logging, Real-Time
    • Error Codes
    • Non-Volatile memory with overwrite
    • Self-Preservation; Hi-Temp events trigger action and recovery
  • Connectivity via Bluetooth, USB

Common PCB Interface:
PCB modules share a "common interface connection" that allows for stacking and grouping of additional modules.

Software:
  • User-Programmable through .NET
    • Open Source License on Firmware and Config Wizards
    • Support for multi-language/localization
    • Multi-platform Support for Windows, Apple, Linux, Android
    • User-defined configuration parameters; a must for racers and tinkers
    • Get, Set, Backup, Restore Configuration!
    • Help Guide Online
    • Dynamic Controller Update service: Firmware/Configuration software updates linked to online notification service.
Note: The bullet heading “User-Programmable through .NET” is not part of the circuit board, but rather a set of software applications that affect hardware, usability, and customization. It is sort of like a 4th module in terms of real work, and perhaps we shall identify it as such shortly.
 
A good design spec will identify all the possible influences from a distant perspective: Scope out the boundaries, understand the complexion, and identify the roles of each part – how they interact and they affect the project as a whole. The classification is meant as a study, and target of conversation.

At present, the proposal for Version 1 of the BBC is directed at bicycles and high-powered bikes which infer motorcycles, though it has not been explicitly stated as such.

Please refer to the Glossary of EV Technology for definitions.

  • Electric Vehicle
    • Auto (4+ wheels)
    • Motorcycles
      • Motorcycle
      • Motocross
      • Moped/Scooter
      • Other: Custom, Racers
    • Bicycles
      • Performance Bike/Light Motorcycle
      • MtB & Cruisers
      • Recumbent
      • Other: Custom, Racers
    • Other: TBD
  • Battery
    • LiPo (default chemistry unless otherwise specified)
    • LiFePO4
    • NiCd
    • Nitro-Lithium: a Future product
  • Motor(s)
    • Brushed
    • Brushless
    • Broom
    • Sensored
      • HE
      • Encoder
    • Sensorless
    • Other: TBD
  • Throttle(s)
    • HE
    • POT
    • Encoder
    • Other: TBD
  • Ebrake
    • HE
    • Mechanical
    • Other: TBD
  • Controller et al
  • BMS
  • Charger
    • Portable
    • Main
    • Petrol (cheater!)
  • Auxiliary Systems
    • CA
    • iPod
    • Cop-Away: a Future product
    • Other: TBD
  • Lighting
    • Headlights
    • Taillights
    • Navigation Lights
    • Running Lights
    • Groovy lights
    • Bat Light
    • Any other damn light we can think of…
  • Alarm Systems
  • Communication
  • Audio
  • Stealth
  • Hazard & Safety
  • Repair & Resources
  • Laws
 
This is a block diagram of a typical ebike controller with standard features. The Hall-Effect sensors (HE) are optional or not present in R/C motors.

ebike-basic-block.png


High-level block diagram of the proposed 3-Module design.

3-Module-proposed.png


More diagrams will follow shortly as we flesh out the details. :)
EDIT: Images slightly updated on 2010-08-20.
 
MPS – Main Power Supply
Working Detail Spec – Proposed
Date: Submitted on 2010-08-20
Version: in sync with BCC spec

Description:
MPS supplies regulated main power from the batteries (via FET board) to the EV system, and facilitates the connectivity of the MCU and Auxiliary power for ancillary devices, including but not limited to Lighting, CA, and Alarm. The MPS Auxiliary power circuits are robust enough to provision street-legal lighting for a motorcycle* with capacity to spare for additional low-power devices.

Battery Input - Low Current:
  • Supports 17 up to 150V (general concensus)
  • Direct Battery tap from FET boards, 36W max
  • Step-Down Switched Regulation to 12V
  • HV protection on PCB layout.
Main Switch:
  • On|Off|Alarm|Aux.
  • Arc Protection circuit to extend switch life.
  • Switch may be remotely located off-board.

Health:
  • Pads for off-board location.
  • Indicator light(s) for On/Alarm/Aux.
  • Provide feedback from MCU if system error.
  • Can be wired to Main Switch LED.

Circuits:
  • Main Bus:
    • 12V Rail, 2-3A (24-36W) for Version 1 (locked).
    • Potential to scale up or stack for more capacity
    • Switching Regulated – architecture tbd
  • MCU Out: 3.3 or 5V @ 100mA minimum. Actual voltage is dependent upon MCU selection. Current maximum tbd.
  • Driver Circuit/FET Out: 12V Rail provides supply. Conditioning if any is provided on the FET board (locked).
  • Aux 0:3.3V 400mA target output, V-adj, Designed for auxiliary devices and traditional/legacy battery lighting.
  • Aux 1:3.3-4.1 3A max LED Headlamp supply, V-adj, Current controlled, upgradable. Designed for headlamps < 12V such as HP-LED light bar (Example: Cree). Optionally stuffed.
  • Aux 2: 1.5-12V, W?, V-adj, Designed for auxiliary devices and custom-voltage needs. Provisioned but Not Stuffed.

Alarm Circuit: tbd.

Packaging: tbd

Thermal Cooling: Air. Optional forced - tbd.

Notes:
  • When Switched to ON, all circuits except Alarm are active.
  • When Switched to AUX, only Aux circuits are active and the motor should be allowed to freewheel. Independent On/Off switching of AUX circuits is off-board and out of scope.
  • Each circuit to provide test pads.
  • SAFETY: Provide Discharge pads to allow safe handling of MPS PCB when troubleshooting.
  • POTs may be replaced by discrete resistors for production.
  • Does it make sense to fuse the circuits?
  • Lighting power options are as follows:
    • 12V Headlamp systems (such as the 10W x 2 Halogen) can tap directly off the 12V rail.
    • Aux 0 circuit supports taillights and running lights.
    • Aux 1 supports Multiple Hi-Powered LED Headlamps if the circuit if stuffed.
    • Aux 2 may be stuffed to support other lighting/devices such as Reverse light, Front/Rear L/R signal lights, dual license-plate lights, horn (minimally everything needed for street-legal road motorbike).
    • The Cycle Lumenator 1000 Lumen (single or dual) may require alternate power arrangements due to the 15-100V input.
    • *Support for 12V/55W headlamps would require additional components/upgrading, and is outside the scope for V1.
  • Target no-load consumption: 4W sitting static with power ON, no lights.
  • Additional capacity may be added through board stacking.
 
Still in discussion.

Quick-Spec:
  • One FET board per motor (locked).
  • Battery power connects directly to FET board (locked)
  • Robust Terminal Block for Battery Wires: Presume that multiple FET boards have pass-through battery cabling.
  • Shares Common Interface connection.
    • FET boards will have direct connection to associated MCU, with other options tbd (Tentative)
  • CA connection and Shunt sense located here (locked).
  • High Current Management should move from MPS to here (locked).
  • Arc Protection on Connect/Disconnect
  • Battery Bus Caps co-located, with Discharge methodology for safety
  • Adjustable Regen via hardware/Constant Torque? tbd
  • Charger & BMS connections moved here from MPS
  • Has the largest potential for multiple models and customization based upon system requirements
    • Support TO-247 & TO-264 devices on-board, and provision for off-board hardware devices (locked)
    • No support for TO-220 (locked)
    • Max Voltage rating for on-board components = 150 V (locked)
    • Max Current rating for on-board components = 150 A (locked)
    • 6- and 12-FET versions discussed, possibly co-developed.
 
Still in discussion.

Quick-Spec:
  • Power supplied by MPS (locked)
  • Shares Common Interface connection (locked)
    • FET boards will have direct connection to associated MCU, with other options tbd (Tentative)
  • One MCU or Master-Slave: tbd
    • May be a single unit that controls one motor, or
    • May be a single unit that controls one motor, and slaved from a Master unit, or
    • May be a single unit that controls x-number of motors
  • 2WD Target for V1 (locked)
  • Possible LED Control potential: Brightness, Flashing, Hi/Lo
  • Microprocessor Type: Currently discussing the merits of choice.
 
Still in discussion.

Briefly:
  • One common interface connection to "rule them all" :twisted: :mrgreen:
  • Sub-connections or circuit groupings in parallel are possible. Tenative considerations are:
    • Common Power Connection, isolated
    • Common Features/Signals such as Throttle, EBrake, etc.
    • Motor Phase Signals (one to many; tbd)
    • Future expansion (leave room to the right of the connectors)
  • Connector will probably follow typical 0.100-inch double-row layout convension
  • Connection between boards secured through hardware fasteners
  • Shielding/plating tbd
  • Shared Serial Interface

Quick-Spec:
  • +12V, 2/3A
  • GND, phat!
  • +5V (or 3.3?) for MCU
  • System On: Bool, default (0) = Off
  • Rev: Bool, default (0) = Forward
  • Brake: Bool, default (0) = Off. Alternative: Analog feedback input instead of Bool mated with Throttle.
  • Throttle, common (0-5V); When Brake = 1 then Throttle is progressive Brake/Regen.
  • Alarm: Bool, default (0) = Off
  • Cruise (tbd)
  • 3-Way (tbd)
 
Still in discussion. Nothing new to add at this time.
 
reserved 0
 
reserved 1
 
Back
Top