COMET: Spring Final Review April 21, 2014...COMET: Spring Final Review April 21, 2014 Team members: Julia Contreras-Garcia Emily Ehrle Eric James Jonathan Lumpkin Matthew McClain Megan

COMET:

Spring Final Review

April 21, 2014

Team members: Julia Contreras-Garcia Emily Ehrle Eric James Jonathan Lumpkin Matthew McClain Megan O’Sullivan Benjamin Woeste Kevin Wong

Customer: Lt. Joseph Ausserer, USAF University of Colorado Boulder

Outline • Project Overview

▫ Objectives

▫ Requirements

▫ System block diagram

• Design Description

• Test Overview

• Test Results

• Systems Engineering

• Project Management

Systems and Management

Testing Design

2

Project Overview

Models

Test Stand

Engine

Harness

Shaft

Coupler

Motor &

Controller

Power Regulator

Power Dissipater

Project Purpose and Objectives


Testing Design Project Overview

Project Description • Design and build a Power Extraction Unit (PEU) for a

JetCat P90-RXi mini-turbojet engine (shown below) that will generate 500 Watts of electrical power at 24 VDC.

• Sponsored by Air Force Research Laboratory’s Aerospace Propulsion Outreach Program (APOP)

4

Generator

Harness Engine

JetCat P90-RXi in stock configuration

Solid Works model Systems and Management


Applications • Power extraction devices could be used on variety of military and

civilian Unmanned Aerial Vehicles (UAVs)

• Additional power would replace batteries used to power avionics and/or sensors

• Power extraction unit to weigh

less than equivalent battery,

extending maximum flight time

or flight distance

5



Objectives • Level one

▫ PEU must generate power at 24 Volts DC ▫ PEU must produce this power after the engine has been running no

longer than 1 min 20 s, twice the average start up time ▫ Engine and PEU must be compatible with the WPAFB test stand

• Level two ▫ Reducing thrust by no more than 25% ▫ Increasing specific fuel consumption by no more than 50%

• Level three ▫ Adding no more than the weight than an equivalent battery pack with 30

minutes of power (8 lbs) ▫ Producing 500 W throughout the engine’s RPM operating range

• Level four ▫ PEU to be entirely external to the JetCat engine, making the most

modular solution.

• Red are not met, Green are predicted to be met

6



Design Description



Design Description

8



• Design solution overview

▫ 3-phase brushless motor to act as power generator

▫ Motor has to act as starter until engine can run by itself (~35,000 RPM)

• Critical subsystems

▫ Mechanical

Commercial coupler to connect

engine and motor shafts

Alignment harness to align shafts

▫ Electrical Control switching of motor

between startup mode and power

generation mode

Power conditioning circuitry to

convert AC signal to DC

▫ Software Data acquisition

Modeling

Detailed System Block Diagram

9

Rotor Dynamics

Engine Power Model

P90rxi Engine

Motor Controller Circuitry Motor Controller

(Phoenix 80)

Power

Regulation

Power

Dissipation

Test Stand

Shaft

coupler

Three phase 9.33-16.00Vpp 6.27-5.02 Amps

Direct Current 24 V 2.0 Amps

Motor

B40-8L-

DD

35,000-42,000 RPM 0.0487 Nm – 0.0390

2 kHz 10V PWM motor driving signal

50 Hz Servo PWM

Throttle Signal

Information used to Verify Models

Manufactured

by COMET



Critical Project Elements

10



• Generating electrical power

▫ Req. 1.0 – The design solution shall generate 500 Watts of electrical power

• Attaching motor to engine shaft to provide torque transfer

▫ Req 3.1 – The rotational energy of the main engine shaft shall supply the energy needed via a generator.

• Aligning motor shaft and engine shaft to mitigate vibrations

▫ Req. 3.4 - The design solution shall maintain the engine balance.

• Switching circuitry to force motor to start engine up and then switch to generate electricity

• Convert three phase AC power output from motor into DC power

▫ Req. 2.4 - Power generated shall be transmitted using 24 V DC.

Test Stand Engine

Harness

Shaft

Coupler

Motor &

Controller

Power Regulator

Power

Dissipater Models

Test Overview



Testing Overview: Major Tests

12



Test Stand Engine

Harness

Shaft

Coupler

Motor &

Controller

Power Regulator

Power

Dissipater Models

Test Name Category Location of Execution Completed

Engine Characterization Test Mechanical Software

Boulder Airport ✔

Low RPM Test Mechanical Electrical

Aerospace Instrument Shop ✔

Circuitry Switching Test Electrical Aerospace Instrument Shop ✔

Final System Test Mechanical Electrical Software

Boulder Bomb Squad Facility

• Completion defined as accomplishing test purpose, (e.g. verifying requirements, verifying models, verifying functionality etc.)

Engine Characterization Test • Test Purpose:

▫ Verify MATLAB Simulink engine model for stock engine configuration

▫ Provided baseline engine performance information

• Location: Boulder Airport

• Requirements Verified:

13

Req # Requirement Text

1.2.1 A method of measurement of fuel flow shall exist.

4.1.1 The test stand shall support clamps that are fitted to the engine.

4.1.2 The test stand shall have an axial load cell for means of measuring thrust.

Test Stand Engine

Harness

Shaft

Coupler

Motor &

Controller

Power Regulator

Power

Dissipater Models



Low RPM Test

14

Test Stand Engine

Harness

Shaft

Coupler

Motor &

Controller

Power Regulator

Power

Dissipater Models

• Test Purpose: ▫ Verify shaft connection for

RPM’s between 0-15,000

▫ Verify motor controller circuitry ability to drive motor

• Location: Aerospace Instrument Shop

• Requirements Verified: ▫ No direct requirements

verification, functional test only



Motor Controller to Power Regulator Circuitry Switching

15

Test Stand Engine

Harness

Shaft

Coupler

Motor &

Controller

Power Regulator

Power

Dissipater Models

• Test Purpose:

▫ Verify system can properly switch between motor driving and power generating modes

• Location: Aerospace Instrument Shop


Req #

Requirement Text

2.2.3 Power regulator shall be able to accept voltage input from generator.



Final System Test

16

Test Stand Engine

Harness

Shaft

Coupler

Motor &

Controller

Power Regulator

Power

Dissipater Models

• Test Purpose:

▫ validate entire system can perform to expected standards

• Location: Boulder Bomb Squad Facility


Req # Requirement Text

1.1 The design solution shall not decrease stock thrust by more than 25%.

1.1.1 The design solution shall not output torque high enough such that it will stall the engine.

1.2 The design solution shall not increase the thrust specific fuel consumption by more than 50%.

1.3.1 The design solution must operate above 35,000 RPM, the bottom edge of the engine idle range.

2 Power generated shall be transmitted using 24 V DC current.

3 The design solution shall be able to derive power from a JetCat P90-RXI engine.

3.1 The rotational energy of the engine shaft shall be converted into electrical energy via a generator.

3.4 The design solution shall maintain the engine balance.

4 The design solution, when integrated with the JetCat P90-RXI engine, shall interface with the test stand designed by the customer and the test stand available through CU.

4.1 The dimensions of the design solution integrated with the engine shall not exceed those shown below in Figure 2.4-1.



Final System Test

17

Test Stand Engine

Harness

Shaft Coupler

Motor &

Controller

Power Regulator

Power

Dissipater Models

Budget Subsystems Schedule Project Overview

Measurements Instrument

Output Voltage Direct DAQ input

Output Current Pololu +/- 31 A current sensor

Fuel Flow Rate Equiflow PVDF 0045 flow meter

Engine Thrust Test Stand Button Load Cell

RPM Generator output signal

Load Cell Fuel Tank

Flow Meter

DAQ Chassis

NI

92

05

NI

94

01

NI

92

34

ECU

Engine Generator

Motor Controlling

Circuitry

Voltage Rectifier

Power Dissipater

Current

Voltage

Relays

~30 ft

LabVIEW

Boulder Bomb Squad Dugout

DAQ USB cable

Earth Berm

USB Webcam

Repeater

RPM 35,000 to ~56,000

Test Results



Engine Characterization

19

Test Stand Engine

Harness

Shaft

Coupler

Motor &

Controller

Power Regulator

Power

Dissipater Models



• Acquired average thrust and average fuel flow rate vs. RPM for the P90-RXi engine

• Baseline data for later performance effect analysis

Coupling System

20

Test Stand Engine

Harness

Shaft

Coupler

Motor &

Controller

Power Regulator

Power

Dissipater Models

Req # Requirement Text Verified by:

3.1.2 Connection shall be secure from 0 to 60,000 RPM Coupler torque test

3.3.1 Electric motor and engine shafts shall be held in alignment so the shafts are not offset by >0.15 mm (0.0059 inches) and 1.5°

Coupling system integration/inspection



Coupling System

• Commercial-off-the-shelf coupler rated to operate at 42,000 RPM, above idle speed (35,000)

▫ Shafts began slipping in coupler at 0.7 Nm

Max engine torque of 0.193 Nm

Factor of safety (FOS) of 3.63

Uncertainty in measurement, ~0.01 Nm

Uncertainty does not affect meeting the requirement

• Coupler limits engine operational range

▫ Coupling method from original design would operate over larger part of operational range

▫ To fulfill all original design requirements, new coupler or coupling method would be required

21

Test Stand Engine

Harness

Shaft

Coupler

Motor &

Controller

Power Regulator

Power

Dissipater Models


3.1.2 Connection shall be secure from 0 to 60,000 RPM Coupler torque test



• Alignment Harness

▫ Precision milled for predicted offset of 0.0005” from milling accuracy

Reduced during assembly due to human inaccuracies

▫ Max measured offset between shafts of 0.0034”, for FOS of 1.74

Uncertainty of 0.001” from caliper accuracy

Even with max error, still within requirement range with FOS of 1.34

▫ Angular offset was 0.16°, for factor of safety of 9.4

Uncertainty of 0.23°, from 0.01” measuring inaccuracy

Even with max error, have FOS of 3.85

Coupling System

22

Test Stand Engine

Harness

Shaft

Coupler

Motor &

Controller

Power Regulator

Power

Dissipater Models




3.3.1 Electric motor and engine shafts shall be held in alignment so the shafts are not offset by >0.15 mm (0.0059 inches) and 1.5°

Coupling system integration/inspection

Motor to be used as Starter/Generator

23

Test Stand Engine

Harness

Shaft

Coupler

Motor &

Controller

Power Regulator

Power

Dissipater Models


1.0 PEU shall generate electrical power. Full-system test

1.3 PEU must operate above 35,000 RPM, the lower edge of the engine idle range. Full-system test

• New motor controller selected after original was shorted

▫ Selected based upon availability and functionality (from Aerospace Electronics shop)



Parameter Required Phoenix 80

Current 15A 80A

Speed (2 pole) 35,000 210,000

Voltage 16V 24V

New Motor Controller System Circuitry

24

Test Stand Engine

Harness

Shaft

Coupler

Motor &

Controller Power

Regulator

Power

Dissipater Models

PWM generator

Averaging Circuit

Summing amplifier

Timing chip

comparator

Relays Power



End of motor control circuit comparison

25

Test Stand Engine

Harness

Shaft

Coupler

Motor &

Controller

Power Regulator

Power

Dissipater Models



Frequency: Model: 49.8 Hz Measured: 48.9 Hz Error: 1.84% Amplitude: Model: 5V Measured: 4.94 V Error: 1.2% Duty Cycle: Model: 5.8 % Measured: 6.0 % Error: 3.45%

Power Regulation

26


2 Power generated shall be transmitted at 24 VDC Full-system test

2.2.1 Power regulator shall keep the max ripple below 2.4V Power reg. funct. test

2.2.3 Power regulator shall accept voltage input from generator Motor Controlling-Power Regulating switching test

2.2.4 Power regulator shall accept input frequencies of 1750 - 6250 Hz Full-system test

Test Stand Engine

Harness

Shaft

Coupler

Motor &

Controller

Power Regulator

Power

Dissipater Models

To Ground

• 50 Watt DC-DC regulator outputs 24 Volts ▫ Generator Voltage

drives power limitation

• Voltage ripple of 0.5 Vpp

Bridge Rectifier Smoothing Capacitor DC-DC Regulator

8.05-14.72 V Peaks

24 Volts 0.5 Volt Ripple

3-phase 9.33-16V

8.05-14.72 V ~0.4 Volt Ripple



Power Regulation: Rectifier

27

Test Stand Engine

Harness

Shaft

Coupler

Motor &

Controller

Power Regulator

Power

Dissipater Models

• Test in two parts due to limitations of function generator

• 6 Vpp input from 3 synchronized signal generators



Power Regulation: Rectifier

28

Test Stand Engine

Harness

Shaft

Coupler

Motor &

Controller

Power Regulator

Power

Dissipater Models

• Slightly higher voltage drop than expected

▫ Expect regulator turn on at 39,000 instead of 37,800 RPM



Expected Measured

Voltage drop 1.28 V 1.6 V

Voltage between input and ground Voltage at input to DC-DC regulator

Power Regulation: Regulator

29

Test Stand Engine

Harness

Shaft

Coupler

Motor &

Controller

Power Regulator

Power

Dissipater Models

• Test in two parts due to limitations of function generator

• Used DC power supply to provide voltage input

• Output loaded with power dissipater



Power Regulation: Regulator

30

Test Stand Engine

Harness

Shaft

Coupler

Motor &

Controller

Power Regulator

Power

Dissipater Models

• Voltage output fails original objective of 24-28V output

▫ Output will be corrected before demonstration to Air Force in Late May



Required Expected Measured Error

Voltage 24-28 V 24.0 V 23.8 V 0.8%

Ripple 2.4 V 0.24 V 0.24 V 0.2%

Power (Goal) 500 W

48 W 47.95 0.1%

• Power output fails original objective of 500Watts

▫ Due to lack of COTS regulators capable of boosting 9V to 24V at 500W

▫ Insufficient time to design custom regulator

DC-DC regulator output

Low RPM Test

31

Test Stand Engine

Harness

Shaft

Coupler

Motor &

Controller

Power Regulator

Power

Dissipater Models



• Verified the motor controller circuitry controls the ESC

• Verified the ESC can smoothly commutate to motor from 0-15,000 RPM

• Verified coupler was able to transmit torque between engine and motor

Measured BLDC motor driving signal from Oscilloscope

BLDC motor droving signal from motor control theory application note

Motor Controller to Power Regulator Switching Test Results

32

Test Stand Engine

Harness

Shaft

Coupler

Motor &

Controller

Power Regulator

Power

Dissipater Models

• Verified circuitry could switch between the motor controller side and the power regulator side

• Picture shows oscilloscope probing on the power regulator side



Motor Controller being used to drive motor

Input to Power Regulator

Shows Relays Switched Expected result seen, signal went from 0V to 5.4V

Power Dissipation

• A 2 ohm and 10 ohm resistors dissipate the 48 Watts generated

▫ Measure voltage drop across resistor to verify 24 Volt output of DC-DC regulator

▫ Current sensor used in conjunction to verify power output matches predictions

33

Test Stand Engine

Harness

Shaft

Coupler

Motor &

Controller

Power Regulator

Power

Dissipater Models


2.3 A board shall be created to verify the power output of the power regulation system. Power dissipation functionality test



• A buffer op amp has been added since TRR to make the voltage divider’s impedance compatible with DAQ measurements

Power Dissipation: Results

34

Test Stand Engine

Harness

Shaft

Coupler

Motor &

Controller

Power Regulator

Power

Dissipater Models

• Dissipater used to verify power output of system

▫ Uncertainty is 1.2% of expected system power



Max Uncertainty

Voltage 0.04 V

Current 0.03 A

Power 0.58 W

Engine Model Predictions

35

Test Stand Engine

Harness

Shaft

Coupler

Motor &

Controller

Power Regulator

Power

Dissipater Models

Engine Model (no-load) predictions: Verified Engine Model (load) predictions: To be Tested • Predictions from model indicate requirements will

be met. • Predictions will be verified during Full System Test


1.1 Not decrease stock thrust by >25% Full-system test

1.2 Not increase stock thrust specific fuel consumption by >50%

Full-system test

3 Derive electrical power from a JetCat P90-RXI engine at 24 V DC.

Full-system test



Final System Test: Status

36

Test Stand Engine

Harness

Shaft Coupler

Motor &

Controller

Power Regulator

Power

Dissipater Models

• Currently having problems starting the engine with the integrated design solution ▫ Error: Engine fails due to a temperature bound error

• Cause has been narrowed down to 3 possibilities: 1. Extra fuel forced into system is increasing temperature

2. Engine’s exhaust gas temperature thermocouple is malfunctioning

3. Reduced mass flow due to inlet impedance is causing overheating

• Next Steps: ▫ Iterative testing with decreasing fuel input to see when temperature drops

enough for engine to run

▫ Iterative testing of changing EGT thermocouple position in exit flow

▫ Reduce RPM engine needs to reach to run



Overall Project Results

37

Test Stand Engine

Harness

Shaft Coupler

Motor &

Controller

Power Regulator

Power

Dissipater Models

• Did not achieve customer’s original goal of 500W power generation over the operational range of the engine

▫ Had to take off-ramp design solution due to supply chain problems

▫ Original design was modeled and predicted to achieve customer’s goals

▫ 48 Watts predicted

• When these predictions are verified by final system test, the results can be scaled up to original design goals



Parameter Expected Required

Output Voltage

24 V 24-28V

Thrust Reduction

8-10%


38

Test Stand Engine

Harness

Shaft Coupler

Motor &

Controller

Power Regulator

Power

Dissipater Models

• Original design would have been able to satisfy all functional requirements ▫ Original starter motor/generator would have produced 18V at ~60,000

RPM

▫ Original Power Generating range was 60,000-112,000 RPM, ~55% of engine operational range

▫ Original DC-DC regulator in Power Regulator Subsystem required 18V to begin generating 500W of power.

▫ Custom coupler could be ordered that would operate up to 100,000 RPM, increasing the operational range



System Engineering



Systems Engineering Summary

40

• Define project objectives ▫ Customer-defined requirements ▫ Produce 500W at 24VDC

• Define system requirements ▫ System-level requirements ▫ Minimize impacts on stock system mass,

thrust, specific fuel consumption

• Concept generation and selection ▫ Trade studies and analyses

• Preliminary engineering design ▫ Off-ramps: Lower RPM starter generator,

lower rated coupler, passive signal conditioning

• Component and subsystem testing ▫ Electrical subsystem: Power regulation and

signal conditioning ▫ Mechanical subsystem: Generator

alignment harness, coupling system

• Integration testing • Full-system testing



Work Breakdown Structure

Lessons Learned

41

• Plan for supply chain failures ▫ JetCat not providing original motor ▫ Set hard dates for taking off-ramps ▫ Set margins for other unexpected delays

• Outcome of project has strong dependency on understanding of the schedule ▫ Major milestone: Receive JetCat motor ▫ Electrical: Could not measure signals without

motor ▫ Mechanical: Could not begin manufacturing of

alignment harness



Systems Engineering Issues

42

• Interface and communication with suppliers of critical project elements

▫ Poor/lack of communication from JetCat

▫ No updates about the status of motor

▫ Never received motor from Germany

• Many design changes throughout spring semester

▫ Catch-up from lack of design in the fall

▫ Constant changes to subsystem/integration tests

▫ Devise and plan for contingency off-ramp plans



Project Management



Project Management Summary

44

• Goal: to help the design process operate as smoothly as possible ▫ Understanding of project as a whole ▫ Allocate help where it is needed most ▫ Be aware of schedule and if project is on track or

not

• Key project management lessons learned ▫ Allow more time margins ▫ Do not rely on suppliers/JetCat ▫ Budgets can cause significant delays in project

Obtaining parts sooner would have given more time margins at the end of the project



Budget

45

• Large variation in budget due to team taking off ramp

• Significant over runs of cost in testing area offset by drops in cost of generator and alignment harness



$0.00

$500.00

$1,000.00

$1,500.00

$2,000.00

$2,500.00

$3,000.00

Expected Vs. Actual Expenditures Predicted Cost

Actual Cost

Major Differences in Cost

Total Over budget $1,051.15

Engine $321.00

Other

Broken ECU $591.50

Broken GoJett GSU $184.99

Testing

Flow Meter inserts $60.66

Custom ECU Cable $168.49

Lab Battery Charger $209.99

New Test Stand Battery $86.99

Hours Direct Cost Total Cost

Fall 1,327 $41,475 $124,425

Spring (As of 4/18/14)

1,916 $59,866 $179,597

Total 3,243 $101,341 $304,022

Total project funds spent: $6155.86

Questions?



Backup Slides




48

Test Stand Engine

Harness

Shaft Coupler

Motor &

Controller

Power Regulator

Power

Dissipater Models

• Requirements not verified: ▫ Requirements specific to original 500W generation system



Req #

Requirement Text Reason for Non-verification

1 The design solution shall generate 500 W of electrical power.

Off-ramp design solution not designed to produce 500W

1.3 The design solution shall generate the required power while the engine is operating between 35,000 and 125,000 RPM

The “required power” refers to 500W, which the off-ramp design solution would not be able to produce

2.2.2 Power regulator shall be able to supply 21 Amps. 21 amps is from the 500W design solution

3.2

The generator shall be designed such that the torque from the JetCat P90-RXI engine is sufficient input to generate 500 W at the lowest operational rotation rate, 35,000


3.5

The design solution shall begin to generate 500 W after the engine has been running for one minute and 20 seconds, twice the start up time of the engine.


Engine Test Fire Set Up

49

Test Stand Engine

Harness

Shaft

Coupler

Motor &

Controller

Power Regulator

Power

Dissipater Models

Req #

Requirement Text Verified by

1.2.1 A method of measurement of fuel flow shall exist.

Inspection

4 The design solution, shall interface with the test stand designed by the customer

Final Demonstration at WPAFB

4.1.1 The test stand shall support clamps that are fitted to the engine.

Inspection

4.1.2 The test stand shall have an axial load cell for means of measuring thrust up to 25 lbs.

Inspection

Test Stand

unscrew

unscrew

Pull off

unscrew

50

Coupling System: Additional Tests • Coupler torque test

▫ Test if threaded engine shaft has enough surface area to make a secure connection to coupler

▫ Insert engine shaft into coupler and apply known torque using lever arm and known weight

▫ Find torque at which shaft slips in coupling

▫ If torque reaches 1 Nm (10x greater than expected torque of 0.1 Nm), test will stop without testing to failure

▫ Extra coupling purchased in case coupler is marred during test

▫ If slip occurs before 1 Nm, shaft will be inserted into other side of coupler and adhesive will be used to fill thread gaps

▫ Torque will be applied and measured again after adhesive sets

• Stiffness test ▫ Verify designed harness system is stiffer than stock system

▫ Hang weight from stock starter

▫ Measure displacement

▫ Calculate displacement expected from designed system using and substituting the force from the physical test

51

Test Stand Engine

Harness

Shaft

Coupler

Motor &

Controller

Power Regulator

Power

Dissipater Models


Shaft Coupler

Engine shaft simulator

Lever arm

Known weight, added incrementally

Stock starter

displacement

Known weight

Low RPM Test: Additional Details

52

Test Stand Engine

Harness

Shaft

Coupler

Motor &

Controller

Power Regulator

Power

Dissipater Models

Measurements Instrument Sampling Rate & expected output

Purpose of Measurement

Shaft RPM Engine Ground Support Unit

~1 Hz 0-6,000 RPM

DATA NOT BEING RECORDED Meant as a display of current RPM, not a data recording device. If resonant frequency found the RPM will be recorded by hand.

Frequency Response

PCB +/- 2300 g accelerometer

~25kHz 0-2 g’s

Monitoring vibrations during the test will help reveal any shaft misalignments past the tolerances of the shaft coupler. Measurements will either verify that no natural modes are excited and shafts are aligned or show high amplitude vibrations due to shaft misalignment

Purpose: To ensure shaft connections are stable to ~6,000 RPM Facility: Senior Projects Room or Buseman Advanced concepts lab

Motor Controlling to Power Regulator Switching Test: Additional Details

53

Test Stand Engine

Harness

Shaft

Coupler

Motor &

Controller

Power Regulator

Power

Dissipater Models



Purpose of Measurement

Voltage into Power Regulator

Multimeter N/a 0-1.6 V

DATA NOT BEING RECORDED Measurement is to prove that the relays are switching to the power regulator circuitry. Voltage from 6,000RPM is not high enough to pass the DC-DC regulator

See Low RPM Test additional details slide for other measurements

Purpose: To ensure the relays can successfully and properly switch between the motor controlling circuitry and the power regulating circuitry Facility: Buseman Advanced concepts lab

Power Regulator Functionality Test: Additional Details

54


Purpose: To verify the power regulator is working properly Facility: Tim May’s Electronics Lab The Signal: 3-phase sinusoidal wave, 120o phase shift between each sine wave during the test voltage will vary between 9.33-16V to simulate generator signal at 35,000-60,000 RPM

120o 240o 0o

+V

-V

Test Stand Engine

Harness

Shaft

Coupler

Motor &

Controller

Power Regulator

Power

Dissipater Models

The Function Generators: Three function generators will be used to simulate this signal. All 3 will be synced using the built in syncing channel, then function generator 2 will have a 120o phase shift and function generator 3 will have a 240o phase shift

Power Dissipater functionality Test: Additional Details

55

Test Stand Engine

Harness

Shaft

Coupler

Motor &

Controller

Power Regulator

Power

Dissipater Models



Output Voltage Direct DAQ input 5 Hz 5-24 V

Output Current Pololu +/- 31 A current sensor

5 Hz 0-5 V (corresponding to 0-2 A)

Purpose: to verify the power dissipation system can dissipate at least 50W of power. Functionality includes the current and voltage sensors as well as the labview VI to read and record current, voltage, and power. Facility: Trudy’s Electronics Lab

Selection of New Starter/Generator

56

Test Stand Engine

Harness

Shaft

Coupler

Motor &

Controller

Power Regulator

Power

Dissipater Models


To

rq

ue

(m

Nm

)

Angular Velocity (rad/sec)

Motor Torque/Speed Curve (0,63.13)

(2932.15,0)

Current Starter

𝐾𝑒𝑚𝑓 =𝑉

𝑟𝑎𝑑/𝑠=

𝑁𝑚

𝐴=

0.06313

28= 0.0023

𝑁𝑚

𝐴

𝑉𝑒𝑚𝑓 = ω𝐾𝑒𝑚𝑓 = 628.32 0.0023 = 1.42𝑉

𝑅1 = 𝑉𝑜𝑝𝑝𝑒𝑟𝑎𝑡𝑖𝑛𝑔

𝐴𝑠𝑡𝑎𝑙𝑙=

6

28.08= .214Ω

𝑉𝑎𝑝𝑝𝑙𝑖𝑒𝑑

+

-

I

𝑉𝑒𝑚𝑓

𝑉𝑑𝑟𝑜𝑝 𝑎𝑐𝑟𝑜𝑠𝑠 𝑅1 = 3.24𝑡𝑒𝑠𝑡 − 𝑉𝑒𝑚𝑓 = 1.82𝑉

𝑉 = 𝐼𝑅 → 𝐼 =𝑉

𝑅=

1.82

.214= 8.52𝐴

28.08A

0.85A

τ𝑚 = 𝐾𝑇𝐼 = 0.0023 8.52 = 0.02𝑁𝑚

𝐼 =τ𝑚𝐾𝑇

=0.02

0.0025= 8𝐴 + 2.3𝐴 = 10.3𝐴

𝐹𝑂𝑆 = 𝑚𝑜𝑡𝑜𝑟 𝑜𝑝𝑝𝑒𝑟𝑎𝑡𝑖𝑛𝑔 𝑐𝑢𝑟𝑟𝑒𝑛𝑡

𝑚𝑜𝑡𝑜𝑟 𝑐𝑢𝑟𝑟𝑒𝑛𝑡=

45

10.3= 4.37

Motor Controller System Circuitry at TRR

57

Test Stand Engine

Harness

Shaft

Coupler

Motor &

Controller Power

Regulator

Power

Dissipater Models

PWM generator

Averaging Circuit

Summing amplifier

Timing chip

comparator

Relays Power



Engine: Main Tests

58

Test Stand Engine

Harness

Shaft

Coupler

Motor &

Controller

Power Regulator

Power

Dissipater Models


Stock Engine Characterization: Completed Measured engine fuel flow rate, thrust, and frequency response over operational range Data used to validate MATLAB Engine Model and Rotor Dynamics Calculations, also provided baseline performance

Engine

Test Stand

LabView VI

Load Cell

Fuel Tank

DAQ Chassis

NI

92

05

NI

94

01

NI

92

34

ACC

Quantity Results

Max Speed 131,000 RPM

Max Speed During Startup

53,000 RPM

Thrust at Max Speed 19.8 lbs

Max Fuel Flow ~330 mL/min

Max Temperature 725°C

Full System Test

59

Test Stand Engine

Harness

Shaft Coupler

Motor &

Controller

Power Regulator

Power

Dissipater Models


Req # Requirement

1.1 The design solution shall not decrease stock thrust by more than 25%

1.2 The design solution shall not increase the thrust specific fuel consumption by more than 50%

1.3.1 The design solution must operate above 35,000 RPM, the bottom edge of the engine idle range.

2 Power generated shall be transmitted using 24 V DC current

3 The design solution shall be able to derive power from a JetCat P90-RXI engine.

3.1 The rotational energy of the engine shaft shall be converted into electrical energy via a generator.

4 The design solution, when integrated with the JetCat P90-RXI engine, shall interface with the test stand designed by the customer and the test stand available through CU.

4.1 The dimensions of the design solution and engine shall not exceed those shown below in Figure 2.4-1.

Facility: Boulder Bomb Squad Test Duration: 2.5 hours (1 hour travel & set-up, 30 min testing, 1 hour pack up & travel ) Equipment: Test Stand Assembly, Fuel Flow Sensor, Load Cell, Accelerometer, Design solution

Travel

60


• Currently $500 shortfall on travel for available team members ▫ Have funds to take 5 team members and Dr. Starkey

Item Cost Quantity Subtotal

Airfare $350 round trip 7 people $ 2,450.00

Hotel rooms $120 per night 2 nights, 3 people per room* $ 840.00

Per diem $56 per day 8 people, 3 days $ 1,176.00

Rental Car $125 per day for van 3 days $ 375.00

Total $4,841.00

Available $4,359.00

Itinerary Day Activity May 20 Travel to Dayton, OH. May 21 Demonstrate project May 22 Participate in group poster session and return

to Boulder, CO.

Travel Roster Name Role Dr. Ryan Starkey Team Advisor Matt McClain Project Manager Megan O’Sullivan Test Engineer Ben Woeste Safety Officer Jon Lumpkin Electrical Lead Kevin Wong System Engineer Eric James (Tenative) Software Lead

* Considerations have been made to give separate rooms to the men and women of the team; additionally the team’s advisor has been given his own single room

Load Cell for Full System Tests • Measurement

Specialties FX1901 Compression Load Cell

• Measurement Range: 0-10 lbf

• Excitation Voltage: 5 VDC

• Accuracy: 15% of span

61

Documents

COMET: Spring Final Review April 21, 2014...COMET: Spring Final Review April 21, 2014 Team members: Julia Contreras-Garcia Emily Ehrle Eric James Jonathan Lumpkin Matthew McClain Megan