Source for Application of CHV100 in Slewing Control to Tower Cranes manufacturers at Shenzhen INVT Electric Co., Ltd.. Find a quality supplier or manufacturer of Application of CHV100 in Slewing Control to Tower Cranes from China

At present, tower cranes have found wider and wider application in the building industry, such as ordinary multi-storey buildings, real estate projects, high-rise buildings, large railway projects, bridge projects, power projects, and water conservancy projects. Computer-aided design (CAD), microelectronic technology and program-controlled language control technology have found wide application in tower cranes. Where, the use of inverter for the control of the lift mechanism, slewing mechanism and trolley-jib mechanism is a development tendency.

 

The slewing mechanism features greater inertia impact. Excessive start may lead to greater impact, so excessively fast stop and reversal are forbidden; otherwise, the operation may not be steady and the mechanism may also be damaged. A better solution is to use variable frequency speed regulation to implement steady start. Furthermore, with the inverter control, the system control will be simpler, and the system will be provided with multiple protection measures, so that the system is more safe and reliable.
n Variable Control Solution for Tower Cranes

Shanxi Engineering Machinery Factory is professional manufacturer specialized in the production of building cranes (tower cranes). Previously, universal inverters (V/F control) were used. However, excessively low-frequency torque of the machine caused serious jitter of the rotating arm of the crane during start.

 

Presently, the application of INVT CHV100-004-4 (six-pole 3 KW three-phase asynchronous motor) high-performance vector inverter can perfectly solve the above problem. The electric wiring diagram is as follows:

 

 

 

 

Figure 5 Circuit Diagram of Tower Crane Inverter Control System

During reconstruction, no brake resistor was added at the initial stage, and the advance angle of the rotating arm was too large upon stop (40 Hz, lifting one-ton weight). During the start, once in a while jitter occurred to the rotating arm, since the output torque was insufficient upon start (the motor once stopped upon start). However, when it could not stop normally, the driver of the tower crane made reverse operation habitually, and the inverter often jumped to OU2.

 

Later, a brake resistor two times the standard (power) was added, and after the stop parameters of the inverter were optimized, the advance angle of the rotating arm did not reach 20 degrees due to inertia (40 Hz, lifting one-ton weight), which obviously had reached the national standard for building cranes.

 

Such phenomena as stop and jitter never occurred to the motor by means of changing the acceleration/deceleration time and increasing the start torque and start frequency.

P0.01   1          Terminal command channel

P0.03   5          Multi-step operation setting

P0.11   7.0         Acceleration time

P0.12   15        Deceleration time

P1.01   4.0         Start frequency of direct start

P1.02   0.1         Start frequency hold time

P1.05   1          S-curve type acceleration/deceleration mode

P1.06   20        Start segment proportion of the S curve: 20%;

P1.07   20        End segment proportion of the S curve: 20%;

P1.08   0          Free stop

P3.00   30        Speed loop proportion gain;

P5.00   1          HDI1 is digital input

P5.02   1          Forward operation of terminal S1;

P5.03   2          Reverse operation of terminal S2;

P5.04   16        Multi-step speed terminal 1

P5.05   17          Multi-step speed terminal 2

P5.06   18          Multi-step speed terminal 3

P5.07   7            HDI1 terminal fault reset;

P8.16   3            Number of automatic fault reset operations: 10

PA.04   60.0       Low-speed step

PA.06   80.0       Medium-speed step

PA.10   100.0    High-speed step

For other details, refer to Operating Instructions for CHV Series Vector Inverters.

The slewing mechanism of a tower crane has higher inertia impact and excessively fast start may cause greater impact, so if excessively fast stop and reverse operations are conducted, the system may operate unsteadily or even stop, and in serious cases, the mechanism may also be damaged. Therefore, to solve the above problem, please select the INVT CHV inverters with excellent torque characteristics, configure brake resistors of higher power, and set the appropriate acceleration/deceleration time and start/stop mode.