1. Dynamo Bed & Frame Design
Bed & Rrame
n Natural Frequency Beyond Operating Range
n Custom Designed with Epoxy Filled Cavities
n Isolation Pads – No Special Floor Required
n Axial Jack Screw Adjustment
n Consistent Alignment to Dynamometer
n Natural Frequency Beyond Operating Range
n Universal Adapter Plate
n Axial Jack Screw Adjustment
n Integrated Fluid Manifolds, Guarding
n Alignment Features to EMotor Housing
Safety
n Safety box has been built covering all rotating parts.
Fluid Conditioner Design
n Achieving Temperature Extremes, Ramp Rates
n Control of Flow and Pressure
n Operator Safety (Hot and Cold Fluid)
n Temperature Range -30°C to +120°C
n Rate of Change
Ø 20°C/minute-Heating
Ø 10°C/minute-Cooling
n Accommodates Specimen Motor Losses
n Return to Safe Condition for Cell maintenance (relief valves)
n All Stainless Tanks, Piping, Fittings
n High/Low Flow Settings for Hot & Cold ATF
n Integrated Flow, Pressure, Temperature for Measurement and PID
n Dedicated Return Pump from E-Motor Sump
Battery Simulation Design
n Fast Transient Response to Dynamic Events
n Regeneration of Power
n Remote programming from TAS
n Shielding/Noise Mitigation DC Cables
n High Frequency & Power Motor Drive Signals
n Data Acquisition & Control Signals
HEV/EV Motor Test Cell Block Diagram
2. Principle design of the test-bench
The design of the test-bench is composed of a high-speed inverter-driven induction motor as a load and a torquemeter specially designed for this speed level. In addition, a controlled cooling system is applied to guarantee certain operating points during the measurements. The principle set-up is shown in the block diagram below (figure ).
3. Motor
These custom-wound AC induction motors can produce an amazing amount of power and torque at excellent levels of efficiency. Some of the benefits of an AC induction motor are a longer power band, higher RPM, regenerative braking, and easy reversing. They do not require contactor pre-charge resistors or diodes
n The load and test motors are a high-speed AC induction squirrel cage design.
n The load motor is used as a shaft speed controller with the purpose of absorbing and delivering shaft power to and from the motor under test.
n Cooling is accomplished by a closed loop circulating oil bath and a heat exchanger.
n The oil circulates, cools, and filters prior to returning to the motor.
n The grid couplings provide three degrees of freedom to compensate misalignment along the dynamometer shaft.
n Each shaft terminates onto a Spicer universal joint connected to the output shaft of the motor.
n Angular misalignment is handled mainly by the Spicer U
-joints and end-float is absorbed within the Falk coupling.
n In addition to this limitation, maximum speed of the entire test-bench
n The bearings of this component have to be supplied by an external oil-reservoir.
n The induction motor itself is supplied by a frequency inverter and control unit.
n The induction motor has
n maximum speed of max n10,000rpm ,
n field weakening range of 2:1.
n maximum torque is max T = 30Nm.
4 Linear Power amplifier
n This linear amplifier is used to drive the test motors in addition to an inverter supply.
n The reference value input realized by setting the system parameters by analogue input (e.g. potentiometer) or by digital input (e.g. keyboard or bus).
n The bus used in our set-up is the USB or CAN-bus.
n Power Connection
n Cooling Hoses Accessible
n Dual Processor
This hardware and software feature takes high performance digital signal processor (DSP) and adds a second processor that is dedicated to doing the engine simulation and vector control.
By dedicating a processor to these tasks, software update rates of 20 kHz can be achieved, giving a significantly better reproduction of an actual engine torque pulse.
n Inertia Simulation
With the inertia of an internal combustion engine being significantly smaller than a typical AC motor, the drive uses inertia simulation to cancel out the additional inertia of the motor so that the motor inertia appears to be the same as the internal combustion engine that is being simulated.
n Four-Quadrant Operation
The drive has full four-quadrant operation with the ability to limit or block operation in any of the quadrants. Additionally, the drive has the capability to limit power for both motoring and regenerating modes.
n Auto Tuning
The drive features full automatic tuning capabilities that can be operated from either a remote terminal or the drive’s built-in keypad. After entering the motor nameplate data, the auto-tuning algorithm automatically identifies the additional parameters for operating the attached motor and configures itself for operation
5 RPM / Torque Transducer
n The motor shaft torque and speed inputs are connected to the controller to measure total mechanical power and motor efficiency.
n The torque/speed transducer is a non-contact strain gauge that measures the mechanical deformation of a solid shaft connecting the two motors.
n The torque is calibrated to measure shaft torque in inch-pounds from a transducer designed for a full scale torque.
n The closed-loop control region (torque or speed control can be selected) is limited to a maximum speed of 10,000min-1.
6 Control electronics and control panel
n The dynamometer control panel provides manual control of the load and test motor.
n This interface gives the operator visual feedbac k on the state of the inverter, control over the contactors, and immediate control of torque and speed.
n Provides two safety shutdown options - Automatic/ Manual
n Designed to drive opto-coupler circuits located on the inverters.
n The software driver to read out the torque values has been realized with the software package LabView.
EV Motor Dynamometer
The HEV/EV Motor Test Cell is composed of Dynamometer(load motor), Test motor , Liquid and oil cooler and DAS System with controller. This test cell holds true for industrial drives (e.g. ev or hev motor, drives) as well as for other applications (e.g. gear, transmission, industrial pumps or vacuum cleaner). For such applications this test-bench has been designed and realized that features extremely high torque and rotational speed
