Stepper motor driver faults and troubleshooting methods - Database & Sql Blog Articles

Single chip microcomputer STM32L151CCU6

The principle of stepper motor driver is that the operation of stepper motor must be driven by an electronic device. This device is a stepper motor driver, which converts the pulse signal from the control system into the angular displacement of the stepper motor, or: control system Each time a pulse signal is sent, the stepper motor is rotated by one step angle by the driver. Therefore, the speed of the stepper motor is proportional to the frequency of the pulse signal. If the stepper motor driver fails, it will affect the normal use of the stepper motor. Below we use some examples to illustrate the troubleshooting of the stepper motor driver.
Fault phenomenon Once the stepper motor driver is started, the external fuse of the drive is burned and the device cannot be operated. During the inspection, the maintenance personnel found that a power tube was damaged, but because there was no data, it could not figure out the function of the tube. It thought that it was a power-driven front push, and replaced it with a power tube. After power-on, the insurance was burned again. The tube on it is also damaged.
After the maintenance engineer checks, the initial analysis is correct, that is, the fuse is repeatedly blown, the drive must have an abnormally large current, and a power tube is detected to be damaged. But the effect on the tube is not clear. In fact, the tube is a stepping motor power supply driving tube, and the stepping motor is a high voltage starting, and thus has to withstand high voltage and large current. Static inspection, in the circuit of the pulse ring distributor, the resistance of the power supply to the ground is small, but there is no short circuit. According to the number of components in the line and its power consumption, the resistance of the power supply to the ground should not be so small, so it is suspected that the components in the line are damaged.
Power check, found that a chip is abnormally hot. After the power is turned off, the power supply pin of the chip is cut off, and the static check and the increase of the power supply to the ground should be normal. The resistance of the chip to ground is measured to be small. Check the model number of the chip, which is a non-standard model, which is not found in many manuals. After line analysis, it was confirmed to be the main component in the board: a ring pulse distributor.
In order to further confirm the problem of the chip, firstly, the stepping motor power supply driving tube with the same withstand voltage and current power is replaced, the power supply pin of the chip is restored, and the winding of each step of the stepping motor is replaced by a light-emitting diode circuit. After the power is turned on, the light-emitting diodes are all bright, that is, the windings are all energized, which is not in accordance with the line requirements, and the input step pulse does not respond, so it is confirmed that the chip is damaged. However, the chip does not exist on the market. In the case where the space inside the driver housing allows, a ring pulse generator is designed by using a combination line, that is, a combination of a d-flip-flop and a NAND gate existing on the hand, to make a small print. On the board, the original chip is removed and the small printed board is mounted on the pads of the original chip through the leads. The LED is still used as the analog load. After the power is turned on, the stepping pulse is applied to sequentially emit light in the phase sequence. Remove the simulated load, access the host, power on, and the device is operating normally.