Application of Powtran Technology PI500-L in Port Gantry Cranes-POWTRAN-Engaged in intelligent motor control products

Language

Home

Return to list

Application of Powtran Technology PI500-L in Port Gantry Cranes

2019-11-05

A crane is a multi-action lifting device that can vertically lift and horizontally move heavy objects within a specified range. It is also known as an overhead crane, traveling crane, or hoist. A bridge crane spans across large factory workshops, warehouses, railway freight yards, port terminals, and other similar facilities. The overhead crane runs longitudinally along tracks mounted on elevated supports on either side, allowing it to fully utilize the space beneath the bridge structure for lifting and transporting goods without being obstructed by ground-level equipment. It is the most widely used and commonly found type of lifting equipment. A key characteristic of lifting equipment is its intermittent operation: during each work cycle, the mechanisms responsible for loading, transporting, and unloading alternate their functions. Due to the rapid development of modern logistics, cranes have seen increasingly widespread adoption and growth in the market.

As variable-frequency drive (VFD) technology continues to mature, VFDs have become widely adopted in the lifting industry. Based on market demand and taking into account the unique characteristics of the lifting industry, Powtran Technology has specially developed the PI500L VFD—a model specifically designed for lifting applications—on the basis of its PI500 current vector VFD. The PI500L is tailored for the lifting and hoisting sector, employing internationally advanced vector control technology to meet the industry’s stringent requirements for safety, stability, reliability, and efficiency. It is primarily used in lifting machinery found in ports, mining equipment, industrial and mining enterprises, and construction machinery.

I. The PI500-L has the following features:
1. Power range: 0.4 kW to 800 kW
2. Braking Sequence Logic Control
3. Comprehensive motor self-learning function
4. Master-Slave Control Synchronization Technology
5. Comprehensive RS485 communication functionality
6. The control circuit power supply and the main power supply can be controlled independently.
7. Motor control and switching function for Group 2
8. Pre-excitation and start-up pre-torque compensation function
9. Current vector control technology achieves 150% torque output at 0.5 Hz (without PG control).
10. Rich peripheral interfaces and powerful protection features

II. On-site Application Examples:

2.1. On-site Equipment Condition

2.2. On-site application images:

III. Application Summary:

The Powtran Technology PI500L series frequency converters are specially developed for the lifting industry, tailored to its unique characteristics. This frequency converter features excellent low-frequency starting torque, strong current surge capability, comprehensive timing control functions, and a wide speed regulation range with full power ratings. It not only enables soft start and soft stop functions for motors but also incorporates a variety of sophisticated and reliable protection features that safeguard both the motor and the frequency converter, thereby reducing the impact on the power grid and connected equipment. With a standard Modbus RTU communication protocol, it facilitates remote control by users, ensuring reliable and safe system operation.

IV. More Cases

Currently, building hoists widely adopt variable-frequency control to replace traditional power-frequency control, resulting in smoother system operation and significantly enhanced safety and comfort of the equipment. At the same time, this approach reduces the system’s failure rate, boosts production efficiency, and lowers equipment maintenance costs.

Advantages of the plan:

The hoist at Hefei employs two braking systems simultaneously: mechanical braking and DC braking. The advantage of DC braking lies in its rapid response and adjustable braking torque. By combining the strengths of these two systems, the hoist’s safety performance is further enhanced.

An electric hoist is a specialized lifting device installed on overhead cranes and gantry cranes. It features a compact size, light weight, simple operation, and ease of use, making it widely employed in industrial and mining enterprises, warehouses, docks, and other similar locations.

Advantages of the plan:

This type of crane has been retrofitted with a variable-frequency drive to enable stepless speed regulation, thereby resolving the longstanding issue of inability to adjust the crane’s speed during operation. To reduce equipment costs, the main hook and trolley of the electric hoist crane share a single variable-frequency drive. The trolley and main hook are mechanically and electrically interlocked to ensure that they cannot operate simultaneously.

Tower cranes are the most commonly used lifting equipment on construction sites, employed to hoist construction materials such as reinforcing steel bars, wooden formwork, concrete, and steel pipes. A tower crane essentially consists of three main components: lifting, luffing, and slewing.

Advantages of the plan:

The lifting, slewing, and luffing mechanisms adopt variable-frequency stepless speed regulation with soft start and soft stop features, which enhance the overall machine performance and extend the service life of the machinery. The frequency converter controlling the slewing function employs eddy-current braking, thereby improving the safety and reliability of the tower crane control system.

None!