Offboard Electric Vehicle Charger

5/5/2015 KGCOE MSD P15261 Revision 4 ==KGCOE MSD P15263 Offboard Electric Vehicle Charger Joseph Droleskey, Tucker Graydon, Brian Hebbard, Christopher Liess

Pg 1 / 32 5/5/2015 KGCOE MSD P15261 Revision 4 Index

Customer Project Readiness Package (PRP) 3

Customer Requirements 7

Engineering Requirements 8

Benchmarking 10

Risk Management 12

Morphological Table 15

Functional Decomposition 15

Team Schedule 16

System Layout and Design 17

AC-DC Rectification Subsystem 20

DC-DC Control Subsystem 22

Current Control Subsystem 24

Control and Logic System 25

CAN Communication Subsystem 26

Microcontroller 28

Prototype CAD Design 30

Estimated Bill of Materials 31

References 32

Pg 2 / 32 5/5/2015 KGCOE MSD P15261 Revision 4 Multidisciplinary Senior Design Project Readiness Package

Project Title: Electric Superbike Off-board Charger Project Number: P15261 (MSD will assign this) Primary Customer: (provide name, phone EVT, Josh Jones, Wheeler Law, Derek Gutheil number, and email) Sponsor(s): (provide name, phone MSD Senior Design department number, email, and amount of support) Preferred Start Term: Spring 2015 Faculty Champion: Prof. George Slack, [email protected] (provide name and email) Other Support: Project Guide: Slack (MSD will assign this)

EVT, Josh Jones, Derek Gutheil January 2015 Prepared By Date

Pg 3 / 32 5/5/2015 KGCOE MSD P15261 Revision 4

Project Information

Overview: The RIT Electric Vehicle Team is a student run organization dedicated to promoting the viability of electric vehicles through real world demonstrations of electric drivetrains in action. The team aims to educate people on the principles of electric vehicle design by engaging students in challenging and rewarding projects that cover a wide variety of academic disciplines. The team’s main project is to design, build, and race a high performance electric motorcycle for competition in the 2015 eMotoRacing all-electric race series. The current bike is based off of the frame from a 2005 Kawasaki Ninja ZX6RR, and utilizes two Zero Z-Force 75-7 motors paired with two Sevcon Size6 controllers. In house engineering includes the design and fabrication of a battery management system, battery containment modules, structural framing for the mounting of the powertrain, as well as advanced data collection and analysis software. Based on this, the team is currently in need of a high powered charger that can charge the bike's battery pack in a reasonable amount of time.

Project Goals: The R.I.T. Electric Vehicle Team proposes a portable off-board charger for an electric super bike. In order to compete in the E-Moto Racing series, the team requires an efficient and reliable method of charging the bike's 12 Kwh battery pack. Unlike traditional battery chargers, the superbikes charger must conform to the J-1772 electric vehicle charging standard.

References: [1] http://emotoracing.com [2] http://en.wikipedia.org/wiki/SAE_J1772 [3] https://code.google.com/p/open-evse/wiki/J1772Basics [4] http://batteryuniversity.com/learn/article/charging_lithium_ion_batteries

Customer Requirements (CR): This list of customer requirements of anticipated activities. CR # Imp. Customer Need Description CR1 1 Battery connection Able to safely connect and discount battery. CR2 1 Power on / off Able to safely power on and power off charger Able to know the charging rates, state of charge, CR3 LCD Display 4 charging time, etc. CR4 3 Adjustable Able to select voltage and current

Pg 4 / 32 5/5/2015 KGCOE MSD P15261 Revision 4 CR5 1 J-1772 standard Able to implement given standard(s) Able to communicate with the Superbike's BMS CR6 Communication with the Superbike 3 via CAN Able to charge via J-1772 or 120V Wall CR7 1 Wall connection connection Every facet of the project must be well CR8 3 Documentation documented with instructions where necessary CR9 CR10

Engineering Requirements (ER):

1. Power Requirements a. The charger must be capable of charging a battery from full discharge to full charge in no more than 4 hours while using the J-1772 standard charging station b. The charger must also be capable of operating through standard 120V 15A 60Hz wall outlets. While in this low power mode, the charger must be capable of charging the battery in no more than 12 hours c. The charging system must automatically detect and switch between the low and high power modes 2. Control Requirements a. The charger must be able to output voltage and current to within 20% of the nominal values in either mode. These outputs must also be regulated to within 1% of their set values b. The charger must be able to vary voltage and current through both software and a user interface 3. Communication Requirements a. Needs to conform to the J-1772 communication protocol for use in high power mode b. During all modes of operation, the charger must be capable of communicating over CAN Constraints: Safety is of the upmost importance. It will be a factor in every aspect of the design. The batteries on the Superbike that will be charged have a large capacity, and as such, will not be readily available for testing. The Electric Vehicle Team has access to them and can provide them upon request. Most EVT members can be made available with a reasonable notice for assistance. EVT members will also be a regular part of the design process ensuring that their goals are met.

Project Deliverables: Minimum requirements:

Pg 5 / 32 5/5/2015 KGCOE MSD P15261 Revision 4 ● All design documents (e.g., concepts, analysis, detailed drawings/schematics, BOM, test results) ● working prototype ● technical paper ● poster

Additional required deliverables: ● List here, if applicable

Budget Information: List major cost items anticipated, and any special purchasing requirements from the sponsor(s).

Intellectual Property: There are no IP restrictions on this project

Customer Requirements CR # Imp. Customer Need CR1 1 Battery Connection to charger meets safety standards CR2 1 Power on / off CR3 4 LCD Display CR4 3 Adjustable Outputs CR5 1 J-1772 standard CR6 3 Communication with the Superbike CR7 1 Wall Connection CR8 3 Documentation CR9 1 Overall Design must be User Safe CR10 1 Monitoring of battery charging CR11 1 Adhering to EVT safety protocols

CR # Description CR1 Able to safely connect and disconnect battery CR2 Able to safely power on and power off charger CR3 Able to know the charging rates, state of charge, charging time, etc CR4 Able to select voltage, current CR5 Able to implement given standard(s) CR6 Able to communicate with Superbike's BMS via CAN CR7 Able to charge via J-1772 or 120V wall connection CR8 Every facet of project must be well documented with instruction where necessary CR9 The final implementation must be safe to use even for a person who has never been trained on it

CR10 The charger must monitor the battery status over CAN communication to prevent damage to battery CR11 While working on the charger and with the batteries the team must adhere to all the safety protocols the Electric Vehicle Team has in place and a member of EVT must always be present.

Pg 7 / 32 5/5/2015 KGCOE MSD P15261 Revision 4 Engineering Requirements & Specifications (revision 4)

Unit of Ma rg ina l Ide a l rqm t. # Im porta nc e S ourc e Func tion E ng r. Re quire m e nt (m e tric ) Te st (how a re you g oing to ve rify sa tisfa c tion) Me a sure Va lue Va lue S 1 1 C R 1 B a tte ry C onne c tion B oole a n N/A N/A S yste m Ve rif ica tion a ll plug s a re c onne c te d S 2 2 C R 7 C ha rg e Tim e (J-1 7 7 2 ) H rs < 4 4 0 -1 0 0 % c ha rg e te st on J-1 7 7 2 S 3 2 C R 7 C ha rg e Tim e (1 2 0 V ) H rs < 1 2 12 0 -1 0 0 % c ha rg e te st on 1 20 V S 5 4 C R 1 0 Output Volta g e R ipple Pe rc e nta g e < 5 0 Me a sure output for ripple Me a sure output sig na l for va ria nc e S 6 5 C R 1 0 Output Re g ula tion Ac c ura c y Pe rc e nta g e > 9 9 99 Rom use r se le c te d output S 7 3 C R 6 C om m unic a tions Ov e r C A N S uc c e ss Ye s Ye s Re c ie v e da ta pa c ka g e s from B MS S 8 1 C R 4 Output C urre nt (va ria ble ) A m ps 0 -6 3 0 -6 3 From obse rve d c urre nt le ve ls a t output

Some features have been omitted since they do not necessarily have engineering metrics to rate success. These features include the user interface being simple and user friendly, Certain safety implementations such as key switches and emergency stops. These are addressed in the respected subsystem documentation.

Specifications Below are the current specifications for the charger: They currently based on the XALT 63 Ah High Power LIPO Cells in a pack of 25 connected in series. The list will be continuously updated as more data becomes available.

Parameter Min Expected Max Unit Comments UnderVoltage Lockout 2.6 V Bat. Too low Charge Current 1 15 50 A Depends on Source Charge Voltage 25 50 110 V Pack Size dependent Battery Termination Voltage 4.1 V Accuracy -1 0 1 % Battery Overvoltage Threshold 0.1 V Battery Detection 2.5 2.9 4 V Battery Detection Timer 333 ms Start Charging Delay Timer 1 min Charge Complete Timer 5 min Safety Timer 2910 35 min Based on Charge Param.

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PARAMETERS Required EVT Energica Ego Charge Rate <4hrs Charge Rate <4hrs 3.5hrs Cool Rate 40deg C stability Cool Rate 40deg C stability Not Specified PWR Response 1 sec PWR Response 1 sec Not Specified Capacity 11.544 kWh Capacity 11.544 kWh 11.7 kWh Life 1200 CYCLES Life 1200 CYCLES 1200 CYCLES V/I Reg. Accuracy >99% CFM TBD 90 Output Voltage 50-60V+ 110/220V Cost <$1000 >$1000

Attached Below is a expanded graph of efficiency and voltage characteristics of other EV Chargers analyzed by EnergyStar for approval. These values will be used to compare the end product with what is on the market currently.

MSD Risk Assessment e c d o n o a y t t h i r i l r o e e p v k i e ID Risk Item Effect Cause m Action to Minimize Risk Owner L S I Describe the risk briefly What is the effect on What are the possible L* What action(s) will you take (and by Who is any or all of the project cause(s) of this risk? S when) to prevent, reduce the responsible for deliverables if the cause impact of, or transfer the risk of this following actually happens? occurring? through on mitigation? J-1772 interface The charger will not be IP restrictions/low 1 6 6 Conduct proper research into the Team unobtainable usable with J-1772 demand or supply for the ability to purchase this interface chargers unless an interface adapter is manufactured 1 in house Researching and developing a Damaged equipment, safety mechanism that shuts down injured Current regulation does the charger and electrical system 2 Over current operator/bystander not work 1 9 9 when failure is detected Team Damaged equipment, injured Software fails to detect Debugging code and perform 2 Over current operator/bystander current 1 9 9 testing Team Thorough debugging of code/firmware will be implemented, a microcontroller that can effectively communicate with Microcontroller fails to the BMS will be researched and Battery management Batteries detect a full purchased. Use test equipment to system fails to cut off the overcharge/lifecycle battery/communication ensure that the battery cells will not 3 charge decreases disconnect 3 7 21 exceed or meet 100% capacity Team 4 Input voltage detection Batteries Damaged Microcontroller/software 1 7 7 Thorough debugging of Team fails to detect input code/firmware will be voltage implemented, a microcontroller that can effectively communicate with the BMS will be researched and

purchased Implementation of redundant safety Must replace damaged Improper use, systems and procedures. Adequate equipment/increased overheating, system research and testing to validate 5 Damage to charger cost due to replacement design, short circuit 2 9 18 design Team Lack of oversight, Keep a log of desired incorrect parts ordered, items/components, assign an Not all components are replacement to damaged estimate cost to each system, and Team/Project 6 Design Over-Budget obtainable parts 2 7 14 minimize risk 5. Manager Unforeseen design Team must update/adhere to complications, Risk 5, schedule on a regular basis and Project deliverables Lack of communication maintain communication of any Project 7 Design behind schedule incomplete between team 3 5 15 possible complications or FMEA’s Manager/Team Adequate research will minimize Inadequate components risks. Having multiple concepts per within system, not subsystem/function will provide a Function must be designed to interface backup in case system is proven to 8 System function fails test corrected with other functions 2 6 12 fail. Team Add sufficient vents, fans, and heat 9 System overheats Damaged Equipment Inadequate cooling 2 6 12 sinks. Team Debugging code and perform Software does not detect testing to determine sensor is 9 System overheats Damaged Equipment temperature 1 6 6 recording accurate values Team Debugging code and perform Software does not detect testing to determine code is 10 Battery Cell Detection Damaged Batteries correct number of cells 1 6 6 recording accurate values Team Debugging code and perform Software does not detect testing to determine code is 11 Output Voltage Detection Damaged Batteries correct output voltage 1 6 6 recording accurate values Team

Likelihood scale Severity scale 1 - This cause is unlikely to happen 1 - The impact on the project is very minor. We will still meet deliverables on time and within budget, but it will cause extra work

2 - This cause could conceivably happen 4 - The impact on the project is noticeable. We will deliver reduced functionality, go over budget, or fail to meet some of our Engineering Specifications. 3 - This cause is very likely to happen 9 - The impact on the project is severe. We will not be able to deliver, or what we deliver will not meet the customer's needs.

“Importance Score” (Likelihood x Severity) – use this to guide your preference for a risk management strategy Prevent Action will be taken to prevent the cause(s) from occurring in the first place. Reduce Action will be taken to reduce the likelihood of the cause and/or the severity of the effect on the project, should the cause occur Transfer Action will be taken to transfer the risk to something else. Insurance is an example of this. You purchase an insurance policy that contractually binds an insurance company to pay for your loss in the event of accident. This transfers the financial consequences of the accident to someone else. Your car is still a wreck, of course. Accept Low importance risks may not justify any action at all. If they happen, you simply accept the consequences.

Pg 14 / 32 5/5/2015 KGCOE MSD P15261 Revision 4 Morphological Table

Functional Decomposition

Pg 15 / 32 5/5/2015 KGCOE MSD P15261 Revision 4 Team Schedule Team Joe Droleskey, Brian Hebbard, Chris Liess, Tucker Graydon, Member Role Safety Engineer Project Manger Power Engineer Comms Engineer Tasks  Prototype  Case design  Prototype  Develop for DC-DC or selection AC-DC microcontroller Voltage and  Assist in Rectification firmware MSD II Current PCB Layout  Develop  Develop Regulation, microcontroll software Safety er firmware systems  PCB Layout

Pg 16 / 32 5/5/2015 KGCOE MSD P15261 Revision 4 System Design

Subsystems Covered: 1. Power Switch & Key 6. MicroController 2. J1772 Inlet 7. CAN Bus 3. AC/DC Rectifier System 8. Emergency Systems 4. Voltage Control System 1. Relays 1. DC-DC Controller 2. J1772 Shutoff 2. Current Limiter 9. Temperature Control 3. Output 10. Programing Interface 5. User Interface

1. Power Switch and Key Both the Key and the Switch are need to turn on the overall charger system. A Master key is utilized to arm the switch to be toggled on, this is done so that no unauthorized personnel have access to the charger. The switch turns the power for the logic circuit on so that the user may begin interfacing with the charger.

2. J1772 Inlet This is the female socket for the J1772 to plug into. A pilot signal from the microcontroller is needed to engage the plug and allow it to conduct. There is a proximity pin on the line in that the logic circuit pulls its power from. This proximity line sources approximately 12v.

3. AC/DC Rectifier System Once the J1772 line has been engaged a differential phase AC current flows to the AC/DC rectifier. The current design is that of a Vienna rectifier that is known for minimal power loss over transmission. More can be read in that subsystems documentation.

4. Voltage Control System The Rectifier outputs its DC voltage to the control/regulation system. This system is comprised of 3 parts; the Voltage Regulator, the Current Limiter and the Output socket to the Battery System. The Voltage Regulator utilizes a PWM controlled buck switch converter that steps the voltage down to a selected level based on user input. This is followed by the Current Limiter which actively controls current flow based on the user input and in coordination with the voltage level of the voltage controller. This system is in place to prevent rampant over current from occurring and damaging batteries that are attached. The current limiter then directs the charge to the output port where the batteries are connected.

5. User Interface The User Interface is comprised of a LED or OMLED screen that will display the battery statistics as it charges and any user options that are available at the time. User inputs are selected by use of buttons alongside the screen.

6. Microcontroller The microcontroller in the charger will orchestrate the control systems as well as the communication protocols the the BMS on the bike. A 12 bit PIC microcontroller is currently selected and is being tested. A PIC microcontroller was selected because it has CAN drivers natively built into its architecture and allows for simple hardware interfacing with the BMS CAN line. The PIC also has 24 general GPIO pins as well as many more that can have their function changed on the fly.

7. CAN Bus The BMS CAN bus is interfaced over the built in CAN drivers in the PIC controller. The CAN transceiver

Pg 17 / 32 5/5/2015 KGCOE MSD P15261 Revision 4 hardware is still necessary to convert the signal into CAN Protocol levels. The signals that are received from the BMS are; the battery voltage per cell, the temperature of each cell, and the pressure of each cell. A handshake protocol is also in effect that regularly checks in to make sure connection is establish and no errors have occurred.

8. Emergency Systems A number of systems are in place around the charger's design that allow critical systems to be isolated and to eliminate electrical conductivity in case of an emergency situation. The largest level of isolation is in the form of a set of relays that isolate the charging lines that are within the charger. At any given moment the AC/DC rectifier and the Voltage Controller can be isolated and connections to the J1772 and batteries are severed. Research has been done and as of the first revision solid state relays are the best option. The next level of security is the Emergency Shutoff which cuts the pilot signal to the J1772 and it ceases to conduct. This is handled by the microcontroller. The most passive system in place for safety is the ignition system; no user may access the charger unless they have a master key which indicates they have been trained or are with a trained individual.

9. Temperature Control The temperature control systems monitor the temperature of the high risk systems with a thermistor. If any of the systems gets within a margin of their critical operating temperatures the microcontroller will disable the charge system and warn the user of the system overheating. A feedback system will also be in effect to control fans to circulate air around the components.

10. Programming Interface This is a female usb port by which the charger's microcontroller may be interfaced with by a computer. If for any reason the firmware on the microcontroller needs to be changed this allows for ease of access to the system.

Pg 19 / 32 5/5/2015 KGCOE MSD P15261 Revision 4 AC-DC Rectification This design is based on variant of a dual-boost rectifier, called a Vienna rectifier. It has been modified to be split phase, which is the type of power received by this charger. The main reason this particular design was selected was for the qualities listed below:

1. Switching loss reduction 2. Power factor = 0.997 3. Total efficiency = 97% 4. Tailored for Industrial/High Power Applications

Schematic Definitions ACR/ACY: These represent the incoming split-phase AC power from the J1772, 240V, or 120V power source. Gate Drive Transformer: This component turns the inverted gate bipolar transistors (IGBT) on and off in phase with the line voltage using a PWM cycle of approximately 25kHz. Q1/Q2: IGBTs used to deliver current from their respective phase to the node between C1/C2 during the ON period. C1/C2: Output (offset) capacitors of equal value. When Q1 or Q2 is on they charge linearly via the central node. The charging of these capacitors will offset +VDC and –VDC. L1/L2: Represent the input inductors of the rectifier. +(-)VDC: DC output of rectifier that connected to the DC/DC Regulation from the positive side. D1-D12: Power Diodes. Current spec is D13940 power diode.

Pg 20 / 32 5/5/2015 KGCOE MSD P15261 Revision 4 AC/DC Rectification Schematic

+ VDC 2 2 D11 D5 1 1

2 2 2 2 C1 D8 D7 D2 D1

1 Q2 1 1 Q1 1 2 2 2 2 D10 D9 D4 D3 C2 1 1 1 1 2 2 D12 D6 - VDC 1 1

Gate Driv e Transf ormer

ACR ACY 0

Pg 21 / 32 5/5/2015 KGCOE MSD P15261 Revision 4 Voltage Controller Subsystem Support Document

The current subsystem design for the voltage controller is a PWM controlled Buck Switch converter. Attached is a example circuit diagram where a simple converter is implemented. Previously voltage was attempted to be regulated utilizing a single branch motor controller however for higher voltages its effectiveness fell. The PWM controlled buck converter however can handle voltages and currents around that of the J1772 and the switching style of the converter means it has very low power loss as a regulator. Looking at the attached circuit the input (V+) is supplied from the AC/DC rectifier and is a fairly unregulated DC voltage. The control circuit voltage (VCC) is supplied from the logic power system and the PWM signal is an output if the microcontroller. The PWM signal is run through a flip flop and the PWM and ~PWM are ran to the gates of 2 power NMOS devices. The top device allows conduction of V+ through the inductor and to the batteries. When the top gate shuts off, the bottom turns on and the load goes to ground. By utilizing a PWM the load can have a voltage modulated across it that sweeps from the input voltage (100%) to 0V (0%). An ideal modulation frequency is being determined, 100-500 Hz is a good range and offers steady stage voltages, however higher switching rates have less ripple on the output and require less filtering. Other regulator designs are being pursued, but a PWM Buck Converted seems the most reliable. The Current limiter is after the Voltage Regulator and will be dynamically related to the voltage of the regulator and will have a cap to prevent over-current from damaging the components on the batteries. This component can most likely be handled by a IC from TI or Linear Technologies, it is still being researched.

The output of the PWM'd voltage can be averaged and filtered with a simple RC filter tuned to the frequency of the PWM signal.

Current Regulation

A reference voltage will be applied to a leg of a comparator while the other leg is attached to the load line. The comparator will then respond to a resistor or transistor network to modify the inbound current to the load. By being able to control the reference voltage with a digitally variable resistor the current allowed through the load can be controlled by preventing it from drawing the limit set by a controller.

Control / Logic Circuit

The main controller of the charger is currently selected to be a PIC microcontroller specifically the PIC18f46k22. This controller offers 27 analog pins and 5 registers of 8 digital IO pins. There are 7 onboard timers that can be used with up to 3 interrupt capable pins. Of the timers onboard 4 are 16 bit and 3 are 8 bit counters. There are 5 total PWM pins, this can also be expanded using gate driver chips communicating with the chip over SPI. The DRV8301 gate driver chip from TI is being considered since the EVT already has a few of them to spare. Currently the EVT CAN drivers contain 9 objects that are recognized on the system. And a total of 13 message IDs that are possible following the object. The microcontroller in the charger will act as a single node on the CAN bus and will have the capability to read any messages that are status messages or flags from the BMS.

Figure 1Pilot Signal View

Figure 2 CAN Toplology

CAN IDs and Messages

BMS_6 0xB Device IDs BMS_7 0xC GTW 0x1 BMS_8 0xD IMU 0x2 BMS_9 0xE BMS_1 0x6 BMS_10 0xF BMS_2 0x7 BMS_3 0x8 BMS_4 0x9 BMS_5 0xA Can Gateway Messages REQUEST_STOP_TRANSMIT 0x10 REQUEST_TRANSMIT_DATA 0x11 Data Sender Mes- REQUEST_NAME_FIRMWARE_VERSIONsage IDs 0x12 REQUEST_DEVICE_DATA_TYPESERROR_FLAGS 0x05 0x13 RESET_ALL_DATA_SENDERSNAME_AND_FIRM 0x06 0x20 GTW_UPDATE_NOTIFIERWARE_VERSION 0x30 GTW_UPDATE_DATADATA_TYPE 0x07 0x31 GTW_UPDATE_CHECKSUMUPDATE_CLEAR_ 0x08 0x32 TO_SEND Pin # Function/ Assignment UPDATE_CHECK- 1 MCLR / Programming SUM 0x09 2 RA0/AN0/Fan Control DATA_01 0x11 DATA_02 0x12 3 RN1/AN1/Thermocouple DATA_03 0x13 4 RN2/AN2/ Relay #1 DATA_04 0x14 5 RN3/AN3/ Relay #2 DATA_05 0x15 6 RN4/AN4/ Pilot Relay DATA_06 0x16 8 RE0/AN5/ Button #2 DATA_07 0x17 9 RE1/AN6/ Button #3 DATA_08 0x18 10 RE2/AN7/ Button #4 12 Vcc 14 RA6 / Button #5 19 SCK2/SCL2/SPI 20 SDI2/SDA2/SPI 22 SS2/SPI 25 RC6/AN18/ Display Microcontroller Pinout and Wiring 26 RC7/AN19 / Current Potentiometer 27 SD02/SPI Pg 27 / 32 28 RD5/AN25/ Button #5 29 RD6/AN26/TX2 (CAN) 30 RD7/AN27/RX2 (CAN) 32 Ground 39 PGC / Programming 40 PGD / Programming 5/5/2015 KGCOE MSD P15261 Revision 4 ated to display its integration as the control unit for the system. A pinout table can be seen below de- picting which pins are assigned each roll for the other subsystems and what they may be used for. As of the 4th revision there is 1 free Serial Protocol Interface register (SPI) to be used since the can transceiver from Linear Technology utilizes TX/RX to communicate with CAN. The other SPI register is taken up by the gate driver used to distribute the PWM signal to the fast switching power MOSFETs in the Dc/DcThe converter system can subsystem. be programed through the 3 pins noted in the diagram, these are hooked up to the PICkit which will be accessible through the exterior. 4 user input buttons and the LCD screen are accounted for. The screen chosen, a parallax screen that has built in drivers and controllers decreases the pins needed to one data in pin. One pin is reading in analog voltages from a thermocouple within the critical subsystems to detect if the system temperature rises suddenly or overheats. If this happens there is a pin utilized to turn on a set of fans to cool down the components and if an overheating error occurs the system will shut off. # of the systems major relays are shown on the diagram; 2 are the high voltage relays in the main current drawing line and one is the relay used to trigger the pilot signal to tell the J-1772 to conduct. The last pin is used to write out values to a digital potentiometer in the current limiting system which sets a voltage reference that a comparator uses to toggle the output on or off if the current reaches the threshold.

Prototype CAD Design

1. J-1772 Charging Station 2. MSD P15261 Fast Charger 3. EVT Motorcycle Battery 4. Standard J-1772 Cable 5 7 5. Emergency Shutoff Button 8 6. Key lock / Power Switch 7. OMLED Display 8. User Interface, Directional Buttons 6

Subsystem Bill of Materials (BoM)

Component Size Model Cost/unit Total Site AC-DC system Mosfet/IGBT 600 V, 50 A NGTB50N60FWG $2.38 $4.76 http://goo.gl/l954ba Diode 600 V, 50 A 512-RHRG5060_F085 $3.91 $46.92 http://goo.gl/Ovu3dB Capacitor (for Vripple) 4700 uF LLH476M125S1G5T60K $2.69 $32.25 http://goo.gl/cUUe87 Gate Driver 50kHz-100kHz PA0185NLT $3.00 $3.00 http://goo.gl/n5N8oJ

DC-DC System Power MOSFET 300V, 88A, 40m IXTH 88N30P 9.53 133.42 http://goo.gl/Gmf9yS Gate Driver 6-60V, 1.7A DRV8301 2.5 10 http://goo.gl/4y3z9p DC Relay 600VAC, 90A CWU2490 98.77 98.77 http://goo.gl/VHBCIN AC Relay 600VAC, 90A D2490 85.19 85.19 http://goo.gl/qzJ1gS J1772 Connector N/A DSIEC2f-EV32S-NC 98 98 http://goo.gl/TwhikR

Total: 512.31

Pg 31 / 32 5/5/2015 KGCOE MSD P15261 Revision 4 References

1. http://publications.lib.chalmers.se/records/fulltext/184817/184817.pdf

2. http://www.ixys.com/Documents/AppNotes/IXAN0001.pdf

3. https://www.energystar.gov/ia/products/downloads/Electric_Vehicle_Scoping_Report.pdf?0544-2a1e

4. http://www.microchip.com/wwwproducts/Devices.aspx?product=PIC18F46K22

5. https://eewiki.net/display/microcontroller/CAN+Example+-+ATmega32M1+-+STK600

6. http://www.vicorpower.com/documents/application_notes/an_ConstantCurrent.pdf

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