New energy forklift power system controller

 The origins of forklifts can be traced back to 1917. After more than 100 years of development, forklifts, as the main mechanized loading and unloading, stacking and short-distance transportation tools, liberate people from heavy primitive human handling. Forklifts are widely used in factories, warehouses, ports, stations and other industrial and logistics fields around the world, becoming an indispensable part of the national economy.

In recent years, the global forklift market has shown an upward trend. In 2021, the global sales of forklifts hit a record of 2.34 million units, a year-on-year increase of 47.89%. Among them, China's forklift sales reached 1.1 million units, a year-on-year increase of 37.4%, becoming the world's largest forklift producer and consumer market.

With the vigorous development of the new energy industry, new energy forklifts with batteries as the power source have become the future development direction of the industry. In 2021, China's new energy forklift sales will reach 657,800 units, a year-on-year increase of 60.33%, and will continue to maintain rapid growth in the future.

Compared with traditional internal combustion forklifts, new energy forklifts further optimize the performance of forklifts, with the advantages of high energy conversion efficiency, low noise, no exhaust emissions, and convenient control. In addition, the new energy forklift is small, flexible and easy to operate, and is more suitable for occasions with high requirements for environmental conditions, such as workshops, warehouses, automatic storage systems and large supermarkets. The development of new energy electric forklifts will bring more convenience and environmental benefits to the forklift industry

Today I will share with you a simple way to measure the power module of the controller. This method is suitable for all AC controllers.

DC series electric motor plays a key role in forklift driving and operation, and its control mainly covers starting, speed regulation, reversal and braking. These control methods are designed to meet the changing needs of forklift trucks while driving and operating.

Commutation control of series excited DC motors

The DC series motor used in the electric forklift depends on the adjustment of the electromagnetic torque for the change of its rotation direction.

According to the formula of electromagnetic torque T=KφI, we can find that the direction of electromagnetic torque can be changed by changing the direction of armature current I or magnetic flux φ; However, changing the direction of the armature current and magnetic field cannot change the direction of the electromagnetic torque. Therefore, the reversal of the series motor is often achieved by a reversing switch or other electrical equipment, which reverses or replaces the armature or excitation winding. In practical applications, the armature reverse connection method or the excitation winding reverse connection method is often used, instead of the replacement excitation winding method.

In the electric forklift power unit, when the forward contactor is closed, the motor is in a forward rotation state; Whereas, when the reverse contactor is closed, the motor is reversed. By changing the direction of the armature current or excitation current, or by changing the polarity of the excitation winding, the commutation control of the motor is realized. However, the use of two sets of excitation windings with opposite windings will lead to a complex structure and an increase in the volume of the motor, so the first two methods are more commonly used in practical applications.