GE IC3645SR4U404N2, IC3645SP4U400N3 Solid-State Reversing, More Features with Fewer Components

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BASIC OPERATION AND FEATURES

SX TRANSISTOR CONTROL

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following description provides a brief introduction to examples of some of these features.

Section 1. 2 Solid-State Reversing

The direction of armature rotation on a shunt motor is determined by the direction in which current flows through the field windings. Because of the of the shunt motor field only typically requires about 10% of the armature current at full torque, it is normally cost effective to replace the double-pole, double-throw reversing contactor with a low power transistor H-Bridge circuit (Figure 4).

armature, the motor performance curve can be maximized through proper control application.

Section 1. 4 More Features with Fewer Components

Field weakening with a series wound motor is accomplished by placing a resistor in parallel with the field winding of the motor. Bypassing some of the current flowing in the field into the resistor causes the field current to be less, or weakened. With the field weakened, the motor speed will increase, giving the effect of “overdrive”. To change the “overdrive speed”, it is necessary to change

LINE POS

FUSE

CAP

Q2

A1 +

ARM A2 -

Q1

Q3

F1

Q4

Q5

F2

Q6

the resistor value. In a separately excited motor, independent control of the field current provides for infinite adjustments of “overdrive” levels, between motor base speed and maximum weak field. The desirability of this feature is enhanced by the elimination of the contactor and resistor required for field weakening with a series motor.

With a separately excited motor, overhauling speed limit, or downhill speed, will also be more constant. By its nature, the shunt motor will try to maintain a constant speed downhill. This characteristic can be enhanced by increasing the field strength with the control. Overhauling load control works in just the opposite way of field weakening, armature rotation

NEG

Figure 4

By energizing the transistors in pairs, current can be made to flow in either direction in the field. The armature control circuit typically operates at 12KHZ to 15KHZ, a frequency range normally above human hearing. This high frequency coupled with the elimination of directional contactors, provides very quiet vehicle operation. The field control circuits typically operate at 2 KHZ.

The line contactor is normally the only contactor required for the shunt motor traction circuit. This contactor is used for both pre-charge of the line capacitors and for emergency shut down of the motor circuit, in case of problems that would cause a full motor torque condition. The line can be energized and de-energized by the various logic combinations of the vehicle, i.e. activate on key, seat or start switch closure, and de-energize on time out of idle vehicle. Again, these options add to the quiet operation of the vehicle.

Section 1. 3 Flexible System Application

Because the shunt motor controller has the ability to control both the armature and field circuits independently, the system can normally be adjusted for maximum system efficiencies at certain operating parameters. Generally speaking, with the ability of independent field and

slows with the increase of current in the field.

Regenerative braking (braking energy returned to the battery) may be accomplished completely with solid-state technology. The main advantage of regenerative braking is increased motor life. Motor current is reduced by 50% or more during braking while maintaining the same braking torque as electrical braking with a diode clamp around the armature. The lower current translates into longer brush life and reduced motor heating. Solid state regenerative braking also eliminates a power diode, current sensor and contactor from the circuit.

For GE, the future is now as we make available a new generation of electric traction motor systems for electric vehicles having separately excited DC shunt motors and controls. Features that were once thought to be only available on future AC or brushless DC technology vehicles systems are now achievable and affordable.

January 2000

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Contents Installation and Operation Table of Contents 41-45 20-4046-52 57-62Motor Characteristics Basic Operation and FeaturesSolid-State Reversing More Features with Fewer ComponentsFlexible System Application Slows with the increase of current in the field1.c Control Acceleration 1.b Creep Speed2 Current Limit 3.c Pedal Position Plug Braking4.b Speed Limits 6 Steer Pump Contactor Time Delay4.c Proportional Operation for Dual Motor Vehicles 5 Ramp Operation 5a Ramp Start7 On-Board Coil Drivers & Internal Coil Suppression Diagnostics 1 Systems DiagnosticsSystem Protective Override 1 Static Return to Off SRO 2 Accelerator Volts Hold Off4 Battery Discharge Indication BDI 3.a Maintenance Alert & Speed Limit3 Hourmeter Readings 4.a Internal Resistance CompensationBasic Operation and Features Argument Outline DRAWINGS, Elementary Drawings and INPUTS/OUTPUTSPart Number Outline SX-3 and SR-3 Package Size Drawings and INPUTS/OUTPUTS Section DRAWINGS, Elementary Drawings and INPUTS/OUTPUTS ControlPIN Connections to Main Plug 23 PIN and Y Plug 12 PINDiagnostic Status Codes Medium-Power Signals Level MP High-Level Signals Level H2.d. High Power Signals Level HP Cable Spacing Guidelines328A1777G1 CleanerReconnect plugs General Troubleshooting Instructions Traction Control Codes No seat switch or deadman switchTraction Status CodeDescription of Status Cause of Status Indication Reverse directional switch is closed onDirection selected Start switch fails to closeAccelerator depressed with no KEY Negative Same time Directional switches are closed atBoth the forward and reverse Initial key switch closure Start switch closed on power up afterDischarged battery Forward direction Motor field current is high on start upReverse direction Motor field current is too high during Volts DC Power supply is less than 10 voltsRun mode Traction Controller Slave/auxiliary control Open thermal protector TP or Transistor over temperatureLow Motor armature offset voltage is tooArmature transistor did not turn off ProperlyLook Ahead test for A2 volts less Than 12% of battery voltsArmature transistor did not turn on Contactor closes Motor field current is too low duringCapacitor volts are low before the line Line driver input P2-17 is less Controller motor current sensorInput too low during running Description Armature transistor limit Armature current exceedsVerify connection between the master control P21 Traction Status Code Symptom TMM Status Codes TemperatureSteer Plug P5 pump is shorted to positive Plug P8 pump is shorted to positive Corrective Actions TROUBLE-SHOOTING Diagram YES Possible Cause SymptomPump Open thermal protector TP1 or Transistor is over temperaturePump Controller motor current No power to pump motorSensor input is missing Control rangePower Transistor Q1 did not turn on Power Transistor Q1 did notTurn off properly With no pump contactor, controlContactor closes Capacitor volts are low after the lineCheck Controller motor currentSensor input voltage polarity Voltage at capacitor 1C is less than Volts Battery voltage is less thanTMM7A TMM7A Outline Drawings 3 TMM Pump Control ConnectionsSTART-UP Display Sequence Adjustable FeaturesRemarks Accessing Stored Status Codes With GE HandsetAction Function Function 10 Field Current for Regen Battery volts Set units Battery VoltsInternal Resistance Compensation Function 16 Stall Trip Point with % ON-TIME PushFunction 26 Base Ratio Function 19 Maintenance Code Tens and Units Hours SETFunction 25 Monitor Function 28 Stored Status Code Count Pointer Push Function 49 Mode 1 Field Weakening Start PushFunction 51 Mode 1 MAX Armature % on Function 55 Mode 2 MAX Armature % on Function 52 Mode 2 Armature Controlled AccelerationFunction 57 Mode 3 Field Weakening Start Function 59 Mode 3 MAX Armature % onField Current Summary of Current Limit AdjustmentsFunction 16 Speed / Torque Compensation Function Current LimitFunction 14 not Applicable Function 48 Mode 1 Controlled Acceleration Push Speed / Torque Compensation Table Voltage SettingFunction 49 Mode 1 Speed Limit 2 SL2 Push Function 50 Mode 1 Speed Limit 3 SL3Function 54 Mode 2 Speed Limit 3 SL3 Function 53 Mode 2 Speed Limit 2 SL2Function 55 not Applicable Function 59 not ApplicableApplication Dash DisplaysStandard Dash Displays ConnectionsOutline Drawings Start-Up Display SequenceOperation Turn Angle Potentiometer InstallationSetup Degree Potentiometer for Steer Angle Input Degree Potentiometer Left Right Restrictions Function RS-232 Memory MAP TablesTraction Control Reset to Zero Only Stored Status Code #6 Reset to Zero Only Stored Status Code #5Reset to Zero Only HoursTens/Ones Reset to Zero Only HoursThou/HunReset to Zero Only Dash Display CA-1 Dash Display FWS-1 Reset to Zero Only Stored Status Code #16None Dash Display Ratio2-1 None
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