List and Location of Components on the DriveLab Board

Each 3-phase inverter uses MOSFETs as switching devices. The 3-phase outputs for both inverters are identified as A1, B1 and C1 for Inverter 1 and A2, B2 and C2 for Inverter 2. The power supply for the 3-phase bridge drivers for the inverters is derived from the DC bus through a flyback converter (A-2). The inverters are driven by 3-phase bridge drivers (IR2133). The PWM inputs are isolated before being fed to the drivers. See the following figure.

+/-12V signal supply is required for the isolated analog signals (outputs of the DriveLab box). Switch S90 (C-2) controls the signal power to the board. The green LED D70 (C-2) indicates if the supply is available to the board or not. Fuses F90 (C-2) and F95 (B-2) provide protection for the +12V and -12V supplies respectively.

The board has over-current protection for each inverter. An over-current fault on inverter 1 is indicated by the red LED labeled MOTOR FAULT 1 and an over-current fault on inverter 2 is indicated by the red LED labeled MOTOR FAULT 2.

Probe points are provided to observe the inverter quantities. BNC connector VOLT DC (B-4) is provided to probe the DC bus voltage. Note that the scaling factor of the DC bus input voltage is 1/10. See the following figure.

LEM sensors are used to measure the output current of the inverters. Only phase A and phase B currents are available. The phase C current can then be calculated using the current relationship Ia+Ib+Ic = 0, assuming that there is no neutral connection for the motors. The calibration of the current sensor is such that for a 1A current flowing through the current sensor, the voltage output is 0.5V (scaling factor of ½). See the following figures.

See below for an exhaustive list of the DriveLab board components and their location.

DriveLab Board Chart