Energy-saving control system of rubber-tyred container gantry crane

Abstract

An energy-saving control system of rubber-tyred container gantry crane, wherein the diesel engine-electric generator set is controlled to stop when the crane is idle, and a storage device is utilized to supply power to an auxiliary system of the crane, the system comprises: a monitor unit, a charger, a super capacitor, a capacitor monitor module and an inverter. A charge signal is transmitted by the monitor unit when the crane being at an idle state is decided, the charge signal is received by the capacitor monitor module thereby a charge start signal is transmitted to control the charging of the super capacitor by the charger; the diesel engine-electric generator set is controlled to stop or to slow down when the super capacitor has been fully charged being detected by the monitor unit, the super capacitor is used for supplying the power to the auxiliary system of the crane, the direct current of the super capacitor is converted by the inverter to alternating current for supplying the auxiliary system. The energy-saving control system allows RTG to turn off the diesel engine-electric generator set and to implement the operation intermittently, the oil-saving rate of the entire RTG can reach above 40%.

Description

BRIEF DESCRIPTION OF DRAWINGS

The specific embodiments of the invention will be described by incorporating the following drawings, wherein:

FIG. 1 is a principle diagram of an embodiment of an energy-saving control system of the rubber-tyred container gantry crane of the invention;

FIG. 2 is an operation panel schematic diagram of an embodiment of an energy-saving control system of the rubber-tyred container gantry crane of the invention; and

FIG. 3 is a structural schematic diagram of a static state switch of the embodiment as shown in FIG. 1.

Claims

1. An energy-saving control system of rubber-tyred container gantry crane, wherein the energy-saving control system controls the diesel engine-electric generator set to stop when the crane is idle, and supplies power on line to an auxiliary system of the crane by utilizing an energy storage device, said energy-saving control system comprising: a super capacitor, for applying the energy stored during the running period of the diesel engine-electric generator set to supply power to the auxiliary system of the crane when the diesel engine-electric generator set is stopped;an inverter, connecting to the super capacitor and the auxiliary system, for converting the direct current of said the super capacitor to an alternating current for supplying the auxiliary system;a capacitor monitor module for generating a charge start signal when a charge signal is received or the voltage of the super capacitor is detected to be lower than a first predetermined value;a charger, being supplied by the diesel engine-electric generator set, for receiving the charge start signal and charging the super capacitor; anda monitor unit, for deciding the crane being at an idle state and transmitting the charge signal to the capacitor monitor module, and for controlling the diesel engine-electric generator set to stop or to slow down when it detects the super capacitor has been fully charged; after stopping or slowing down the diesel engine-electric generator set, the monitor unit controls the diesel engine-electric generator set to start or to operate at full speed when it detects the voltage of the super capacitor is lower than the first predetermined value.

2. The system of claim 1, wherein the monitor unit decides the crane being at an idle state in response to an idle signal, which is generated by an energy-saving button disposed on the operation panel of the crane.

3. The system of claim 1, wherein the monitor unit decides the crane being at an idle state upon no operation of the operation handle of the crane for a predetermined period, and generates the charge signal.

4. The system of claim 1, wherein the monitor unit controls the diesel engine-electric generator set to start or at full speed in response to a recovery signal, which is generated by a recovery button disposed on the operation panel of the crane.

5. The system of claim 1, wherein further comprises a static state switch, the super capacitor and the diesel engine-electric generator set are connected to the inverter via the static state switch, and the static state switch is controlled by the monitor unit; when one of the super capacitor and the diesel engine-electric generator set can not supply power, the static state switch will turn to the other.

6. The system of claim 1, wherein the static state switch is composed of a switching relay and a bi-directional thyristor being connected in parallel to the normal open contacts of the static state switch, the switching relay and bi-directional thyristor are controlled by the monitor unit.

7. The system of claim 1, wherein further comprises a first contactor, the super capacitor is connected to the charger via the first contactor, and the first contactor is controlled by the capacitor monitor module.

8. The system of claim 7, wherein the capacitor monitor module is supplied by the diesel engine-electric generator set; when the capacitor monitor module obtains the power supply it detects that the voltage of the super capacitor is higher than the second predetermined value and it causes the first contactor to be closed, when the capacitor monitor module fails to obtain the power supply, it causes the first contactor to be opened.

9. The system of claim 1, wherein further comprises a second contactor, the super capacitor is connected to the inverter via the second contactor, and the second contactor is controlled by the first contactor and a self-lock switch disposed in the monitor unit; when the first contactor and/or self-lock switch are closed, the second contactor is closed.

10. The system of claim 9, wherein the self-lock switch is closed when the closing of the second contactor caused by attraction is detected by the monitor unit, the self-lock switch is opened when the voltage of the super capacitor detected by the monitor unit is lower than a third predetermined value.