There are two types of inverter shutdown.

One form is called "free parking.". As the name implies, it is to quickly "power off" the motor, so that the motor can slide and stop by its own inertia force (off2 stop);

Another form is called "brake stop.". There are many ways to stop the car. For example, off1 stop is to stop at a certain slope deceleration, or off3 "emergency brake" stop (according to the limit braking capacity of the motor).

Second, the means of braking and stopping are: DC braking (that is, a certain amount of direct current is applied to the electricity); dynamic braking (using resistance to dissipate energy); hybrid braking (DC braking + dynamic braking); feedback braking (injecting the power generation current into the power grid); mechanical braking with holding brake.

Parking is divided into ramp parking and free parking (fast parking is also ramp parking, but the ramp wave is steep).

There are also mechanical braking (such as holding brake), energy consumption braking (braking resistance, reverse braking, DC braking, etc.), feedback braking, etc. Whether the brake is required depends on the running state of the motor. When the required stopping time is less than the free stopping time, the brake is required; sometimes the brake is required when the motor is in normal operation, such as when the hook is lowered.

In the drive system composed of power grid inverter motor load, energy can be transmitted in two directions. When the motor is in the motor working mode, the electrical energy is transferred from the grid to the motor through the frequency converter, which is converted into mechanical energy to drive the load, so the load has kinetic energy or potential energy; when the load releases these energy to change the motion state, the motor is driven by the load and enters the generator working mode, which converts the mechanical energy into electrical energy and feeds back to the front converter. These feedback energy is called regenerative braking energy, which can be fed back to the grid through the inverter, or consumed in the braking resistance on the DC bus of the inverter (energy consumption braking).

Where braking energy is generated

1. Heavy load lowering process of lifting equipment

2. Fast deceleration process of large inertia load