1. System Overview Grab Hoist is essentially a general purpose crane system, so the scenario described in this case is equally applicable to a general purpose crane system. The lifting mechanisms of traditional cranes and the motors of large and small vehicle traveling mechanisms are all driven by a wire-wound motor. Since wire-wound motors have resistors in the rotor circuit, the mechanical characteristics of the motor become soft, and the energy consumption is large and the efficiency is low. The speed fluctuation is large and the speed regulation is graded, especially the wire-wound motor has low protection level. In some large-scale open-air lifting equipment, the wire-wound motor is vulnerable to environmental erosion and is prone to failure.
Therefore, in recent years, with the development of frequency converter technology, the speed regulation performance of the inverter has been increasing; at the same time, with the increase in the use of the inverter, the cost of using the inverter is greatly reduced. In recent years, the application of frequency converters in cranes has become increasingly widespread. However, due to the special nature of the crane lifting mechanism load, higher requirements have been put forward for the inverter used in the lifting mechanism. For example, in order to avoid the weight falling due to its own weight when the heavy object is lifted at a low speed in the air, the starting torque and low-speed torque of the frequency converter must be large enough, and the frequency converter should have the function of pre-establishing a magnetic field for the motor, so that the mechanical hold After the gate is opened, the motor can quickly output the torque to ensure that the weight can be raised in time.
The crane mentioned in this case is a lifting device of a garbage transfer station in Wuxi Yiduo Environmental Protection Co., Ltd. The original crane was an Yaskawa G7 inverter. After the inverter was damaged, it was used because it was expensive. The Taiwan Youkang YD5160 inverter, commissioned by technical personnel, the crane has achieved the original performance, stable and reliable operation, no jitter at low frequency and high frequency. Reduce the customer's investment and improve the customer's economic benefits.
Second, the system configuration converter: YD5160-T4 high-performance universal vector inverter voltage: 380VAC; current: 302A; control mode: open-loop VF master switch: three-speed switch
Third, the system function and principle to enhance the control of the organization, using a multi-speed control mode, so that the lifting mechanism in the start, run, stop with a smooth conversion process, to avoid the impact of the lifting stage, so that the hoist operation is stable, safe, reliable.
The wiring diagram of the system is as follows.
The default function of multi-function terminals 5 and 6 is multi-speed command 1 and 2, and the corresponding segment speed is as follows.
Terminal 5 Terminal 6 selected speed
OFF OFF D1-01
ON OFF D1-02
OFF ON D1-03
ON ON D1-04

Related parameters please refer to parameter setting section

See figure (a)

Brake control:
The brake control plays an important role in the safety of the hoist. Generally, the brake is opened when the inverter has a certain frequency output, so that the crane can be prevented from sliding when the brake is opened. The multi-function output terminal of Unicon's inverter has a frequency reach output function, and this function can be used to delay opening the brake.
The working sequence diagram is as follows.
See figure (b)

Multi-function output terminal 9-10, set to 5, the function of this terminal is the frequency arrival output. When the output frequency reaches the frequency set by parameter L4-01, terminal 9-10 closes and the control brake opens. Generally, L4-01 is set to 3~5Hz. When the brake is opened, the inverter has a certain frequency output to the motor to ensure that the motor has enough output torque when the brake is open to prevent the weight from falling.
Parameter L4-01 is the detection frequency value. L4-02 is a hysteresis. It can make different frequencies detected when starting and stopping to open or close the brake at different frequency points. If closed-loop control is used, adjust the F1-11 parameter (deceleration delay detection time too long) during debugging to prevent the brake from opening and reporting excessive speed deviation alarm.
Alarm Output:
Alarm, terminals 18 and 20 are closed, output alarm signal, use this signal to make the inverter close the brake in alarm shutdown to prevent the crane from falling.

Fourth, the main parameters
A1-02 0 No PG/VF control
B1-01 Speed ​​of 0 segment 1 is given by the operator
B2-01 0 DC braking start frequency during deceleration and stop
B2-03 1 DC braking time at starting
C1-01 3 Acceleration time
C1-02 3 Deceleration time
C1-09 2 Emergency stop time
D1-01 9 speed 1
D1-02 25 speed 2
D1-03 47 Speed ​​3
E1-01 380 output voltage
E1-03 9 VF Curve Selection
E2-01 204 Rated motor current
E2-02 1.5 Motor Slip Rating
E2-03 90.2 No-load current of motor
E2-08 0.102 Setting of Core Saturation Coefficient at 75% Magnetic Flux
E2-11 110 Motor Power*
H2-01 5 Frequency Detection 2
H3-05 1F does not use analog input
L3-04 0 Deceleration stall prevention function: invalid
L4-01 2.3 Detection Frequency
L4-02 0.5 Detection Frequency Range
L6-01 4 Over-torque detection 1: Detection/detection of cut-off output during operation
L6-03 3 Time to detect 1 moment
L6-04 4 Over-torque detection 2: Detection/detection of cut-off output during operation
L6-05 250 Detection value of over torque 2
L6-06 3 Time to detect 2 moments
L8-05 1 Phase loss protection effective
L8-07 1 Phase loss protection is effective when output current is less than 5% of rated current

V. Conclusion The frequency converter is used on this crane for a period of time. The customer reflects that the equipment is running smoothly. The start, stop, acceleration and deceleration are smooth and stable. The starting current is small and the noise is low. The crane can completely replace the Yaskawa G5 or G7 inverter. Device.