CN-121984063-A - Wharf crane feedback electric energy collection and load peak value suppression system

CN121984063ACN 121984063 ACN121984063 ACN 121984063ACN-121984063-A

Abstract

The invention discloses a wharf crane electric energy feedback collection and load peak suppression system, and relates to the technical field of wharf power supply and distribution and energy management. The quay crane includes a quay container crane (quay bridge), a track or a tire container gantry crane (gantry crane), and the like, and is hereinafter referred to as a crane. The system acquires instantaneous power, average power, peak duration and power growth rate of a wharf power station in real time, feeds back power and electric energy to a crane, capacity and charge-discharge parameters of an energy storage device and power quality indexes of a power grid, calculates peak impact index, feedback absorption coefficient, peak-valley switching coefficient and harmonic suppression coefficient respectively, compares and analyzes the peak impact index, the feedback absorption coefficient, the peak-valley switching coefficient and the harmonic suppression coefficient with a preset threshold value to generate corresponding strategies, synthesizes results of each module, uniformly schedules the energy storage device, and realizes power fluctuation compensation and stable output through a smooth scheduling strategy, so that an operation mechanism is constructed. The invention can effectively inhibit instantaneous peak power of the wharf power station, improve feedback energy consumption capability, optimize peak-valley scheduling economy, improve electric energy quality and improve safety, stability and energy efficiency of system operation.

Inventors

CHEN CHAOHUI
GUO YUPING
YANG ZHIMIN
ZHAO WEI
ZHENG YUJUN

Assignees

厦门自贸片区港务电力有限公司

Dates

Publication Date: 20260505
Application Date: 20251229

Claims (10)

1. The feedback electric energy collection and load peak suppression system of the wharf crane is characterized by comprising six core parts of a data acquisition module, a peak power monitoring module, a feedback energy absorption module, a peak-valley scheduling module, an electric energy quality optimization module and a power balance control module, wherein the modules are mutually cooperated to form a complete electric energy management and control system, and the specific steps are as follows: ① The data acquisition module is used for acquiring the instantaneous power demand Pinst, the average power Pavg, the peak duration Teak and the power growth rate Rp of the wharf power station to establish a first data set, acquiring the crane feedback power pre, the feedback duration Trec, the total feedback electric energy Erec and the real-time power consumption demand Pload to establish a second data set, acquiring the power grid peak Gu Dianjia Cpeak, cvalley, the energy storage capacity Cbat, the charge and discharge efficiency and the charge and discharge time periods Tchg and Tdis to establish a third data set, acquiring the harmonic content Hmeas, the voltage fluctuation rate Vfluc, the power factor PF and the power grid stability index Sgrid and establishing a fourth data set; ② The peak power monitoring module is used for extracting data of the first data set, calculating and obtaining a peak impact index PCI, comparing and analyzing with a peak impact threshold Pth, judging whether the running state of the wharf power station is stable or not, judging whether the risk of peak impact exists or not, and giving a corresponding strategy if the risk of peak impact exists; ③ The feedback energy absorption module is used for extracting data of the second data set, calculating and obtaining a feedback absorption coefficient RAI, comparing and analyzing with a feedback absorption threshold Rth, judging whether the current feedback energy absorption condition meets the load operation requirement or not, and giving a corresponding strategy if the current feedback energy absorption condition does not meet the load operation requirement; ④ The peak-valley scheduling module is used for extracting data of the third data set, calculating and obtaining a peak-valley switching coefficient PVI, comparing and analyzing with a switching threshold Vth, judging whether the scheduling conditions are met, and giving a scheduling strategy if the scheduling conditions are met; ⑤ The power quality optimization module is used for extracting data of the fourth data set, calculating and obtaining a harmonic suppression coefficient HSI, comparing and analyzing with a harmonic suppression threshold Hth, judging whether the power quality is qualified or not, and giving a corresponding strategy if the power quality is unqualified; ⑥ And the power balance control module is used for carrying out peak value monitoring, feedback absorption, peak-valley scheduling and output results of the power quality optimization module and carrying out uniform scheduling on the energy storage device. The module is characterized in that current/power fluctuation at the power grid side is detected in real time through an electric power flexible regulation mechanism, a smooth scheduling strategy is utilized for instantaneous power compensation, when the peak power demand of the external power grid is detected to be suddenly increased, the energy of a storage battery is immediately called for quick filling, the input power of the power grid is stabilized in a set range, or the storage battery is fully loaded and output when the demand exceeds a threshold value so as to reduce the load of the power grid, and when the power demand falls back to a valley value, surplus energy is absorbed for storage for standby. Through the high-frequency charge-discharge cycle, the storage battery serves as a dynamic energy buffer pool, so that the peak power demand of a power station on an external power grid is effectively limited, severe fluctuation is stabilized, frequency disturbance is avoided from impacting the power grid, the problem of high fluctuation load is solved, and the power grid dependence is reduced. Meanwhile, the module can also solve the feedback electric energy pouring problem, and combines peak Gu Jiacha strategy and residual electricity storage, so that the overall energy consumption cost is obviously reduced, and the multi-objective cooperation of operation stability and economy is realized.
2. The quay crane feedback electric energy collection and load peak suppression system according to claim 1, wherein the data acquisition module comprises a first acquisition unit, a second acquisition unit, a third acquisition unit and a fourth acquisition unit; the first acquisition unit is used for installing a current transformer and a voltage transformer at a wire inlet cabinet of a wharf center transformer substation and accessing an intelligent electric energy meter of a three-phase instantaneous active power transmitter to acquire an instantaneous power demand Pinst in real time; the method comprises the steps of installing a three-phase digital power transmitter with a functional meter on a distribution bus in a wharf power station, counting and outputting average power Pavg, configuring a timestamp recorder at a power acquisition end of an incoming line cabinet, recording the starting time and the ending time of a power peak value, obtaining the duration Teak of the peak power, installing a high-resolution power transmitter on a transformer side or a main bus, obtaining the change rate of the power along with time, obtaining the power increase rate Rp, and establishing the power increase rate Rp as a first data set; The second acquisition unit is used for installing a bidirectional power transmitter of a bidirectional electric energy meter at the output end of a quay bridge regenerative braking loop or a feedback inverter, acquiring instantaneous feedback active power Prec in real time, recording feedback start-stop time and calculating feedback duration Trec by configuring event timer PLC time base records on the feedback inverter, acquiring total feedback electric energy Erec fed back in the current period by connecting an electric energy metering device in parallel at the feedback side, acquiring and summarizing real-time power consumption requirements Pload of the quay at the current moment by installing a shunt intelligent ammeter at the power distribution side/each main load inlet of the quay, and establishing a second data set; the third acquisition unit is used for acquiring peak-to-valley electricity price Cpeak and valley-to-valley electricity price Cvalley of the power grid in peak-to-valley period in the power station energy management system, acquiring capacity Cbat of the energy storage device by installing capacity monitoring equipment on the body of the energy storage device, and acquiring charging and discharging efficiency of the energy storage by installing efficiency monitoring equipment on the side of the energy storage converter Collecting a charging period Tchg and a discharging period Tdis through the running log record of the inverter, and establishing the charging period Tchg and the discharging period Tdis as a third data set; The fourth acquisition unit is used for installing an electric energy quality analyzer and a harmonic analyzer on a main bus to measure and output harmonic content Hmeas, acquiring output voltage fluctuation Vfluc by installing a voltage transient and electric energy quality analyzer on a bus voltage monitoring point, acquiring a power factor PF by using a three-phase electric energy meter with a power factor measurement function in a power distribution cabinet, acquiring a power grid stability index Sgrid by accessing a harbor distribution network automation platform at a power grid dispatching interface, and establishing the power grid stability index as a fourth data set.
3. The quay crane feedback power collection and load peak suppression system according to claim 1, wherein the peak power monitoring module comprises a first calculation unit and a first analysis unit; The first calculating unit is configured to extract an instantaneous power requirement Pinst, an average power Pavg, a peak power duration Tpeak and a power growth rate Rp of the first data set, and calculate and obtain a peak impact index PCI after dimensionless processing.
4. A quay crane feedback power harvesting and load peak suppression system according to claim 3, wherein the first analysis unit is configured to preset a peak impact threshold Pth, and compare and analyze the peak impact index PCI with the peak impact threshold Pth, and obtain a first evaluation result includes: When the peak impact index PCI is less than or equal to the peak impact threshold Pth, the operation state of the wharf power load is stable, the risk of peak impact is avoided, and the monitoring is continued; when the peak impact index PCI > the peak impact threshold Pth, the operation state of the wharf power station is unstable, the risk of peak impact exists, a first early warning instruction is triggered, a first strategy is generated, namely, the peak reduction instruction is directly issued, an energy storage device is driven to discharge, compensation electric energy is provided for a power grid, the instantaneous peak value is reduced, and a control result is transmitted to a power balance control module as an input signal.
5. The quay crane feedback electric energy collection and load peak suppression system according to claim 1, wherein the feedback energy absorption module comprises a second calculation unit and a second analysis unit; The second calculation unit is configured to extract the time feedback active power Prec, the feedback duration Trec, the total amount of feedback electric energy Erec, and the real-time power consumption requirement Pload of the wharf of the second data set, and calculate and obtain the feedback absorption coefficient RAI after dimensionless processing.
6. The dock crane feedback power collection and load peak suppression system according to claim 5, wherein the second analysis unit is configured to preset a feedback absorption threshold Rth, compare and analyze a feedback absorption coefficient RAI with the feedback absorption threshold Rth, and obtain a second evaluation result, where the second evaluation result includes: When the feedback absorption coefficient RAI is less than or equal to the feedback absorption threshold Rth, the current feedback energy consumption condition accords with the load operation requirement, and the adjustment is not carried out, so that the monitoring is continuously carried out; when the feedback absorption coefficient RAI > feedback absorption threshold Rth, the current feedback energy absorption condition is not in accordance with the load operation requirement, namely the feedback energy exceeds the current load absorption range, a second early warning instruction is triggered, a second strategy is generated, namely a feedback energy storage instruction is directly issued, an energy storage device is driven to enter an absorption mode, redundant feedback energy is stored and released when the demand peaks, and an operation state result is transmitted to a power balance control module.
7. The quay crane feedback electric energy collection and load peak suppression system according to claim 1, wherein the peak-to-valley scheduling module comprises a third calculation unit and a third analysis unit; the third calculation unit is used for extracting the peak electricity price Cpeak, the valley electricity price Cvalley, the capacity Cbat of the energy storage device and the energy storage charging and discharging efficiency of the power grid of the third data set And after dimensionless processing, calculating and obtaining a peak-to-valley switching coefficient PVI in a charging period Tchg and a discharging period Tdis.
8. The dock crane feedback power collection and load peak suppression system according to claim 7, wherein the third analysis unit is configured to preset a switching threshold Vth, compare and analyze a peak-to-valley switching coefficient PVI with the switching threshold Vth, and obtain a third evaluation result, where the third evaluation result includes: When the peak-to-valley switching coefficient PVI is less than or equal to the switching threshold Vth, the scheduling condition is not met, the existing operation mode is maintained, and the monitoring is continued; When the peak-to-valley switching coefficient PVI > switches the threshold Vth, the peak-to-valley switching coefficient PVI > meets the scheduling condition, a third early warning instruction is triggered, and a peak-to-valley switching scheduling strategy is generated, namely, a peak clipping and valley filling strategy of low-price electricity charging at night and peak discharging at daytime is executed, so that the overall electricity cost of the wharf power station is reduced, and a scheduling result is transmitted to the power balance control module.
9. The quay crane feedback power harvesting and load peak suppression system according to claim 1, wherein the power quality optimization module comprises a fourth calculation unit and a fourth analysis unit; The fourth calculation unit is configured to extract harmonic content Hmeas, output voltage fluctuation ratio Vfluc, power factor PF and grid stability index Sgrid of the fourth data set, combine a reference harmonic limit value Href allowed by a grid standard, and calculate and obtain a harmonic suppression coefficient HSI after dimensionless processing; The fourth analysis unit is configured to preset a harmonic suppression threshold Hth, compare and analyze a harmonic suppression coefficient HSI with the harmonic suppression threshold Hth, and obtain a fourth evaluation result, where the obtaining a fourth evaluation result includes: When the harmonic suppression coefficient HSI is more than or equal to the harmonic suppression threshold Hth, the electric energy quality is qualified, the current power grid voltage and the harmonic level are in a stable range, adjustment is not needed, and continuous monitoring is performed; when the harmonic suppression coefficient HSI is smaller than the harmonic suppression threshold Hth, the power quality is unqualified, the risk exists in case of exceeding voltage fluctuation, a fourth early warning instruction is triggered, the system issues a harmonic compensation and voltage stabilization instruction, an energy storage grid-connected adjusting function is called, a harmonic absorption and voltage stabilization strategy is executed, the power quality of a wharf power grid is improved, and an optimization result is transmitted to a power balance control module.
10. The system for collecting feedback electric energy and suppressing peak load of wharf crane according to claim 9, wherein the power balance control module is configured to integrate the operation results of the peak power monitoring module, the feedback energy absorbing module, the peak-valley scheduling module and the power quality optimizing module to perform unified scheduling and coordinated control on the energy storage device, and when any module outputs the control result, the power balance control module receives and fuses the result to perform a smooth scheduling strategy according to a real-time power operation state, and the power balance control module includes triggering short-time energy compensation when power fluctuation is too fast and releasing part of energy storage when power is continuously low so as to ensure smooth output of power demand of the power station, thereby realizing a centralized closed-loop operation mechanism of monitoring-decision-instruction-execution-feedback-balance.

Description

Wharf crane feedback electric energy collection and load peak value suppression system Technical Field The invention relates to the technical field of wharf power supply and distribution and energy management, in particular to a wharf crane feedback electric energy collection and load peak suppression system. Background With the continuous improvement of global port automation and electrification level, electric driving modes are commonly adopted in the operation process of wharf equipment such as cranes and the like. The equipment can generate obvious electric power impact and energy fluctuation under the working conditions of start-stop, acceleration, braking and the like, and a typical impact load curve is formed. Especially when a plurality of devices are operated in a centralized manner, the following problems are liable to arise: The main electric equipment of the wharf is a quay container crane (quay bridge), a track or a tire container gantry crane (gantry crane) and the like, the equipment has high power, the load characteristic is a gravitational potential energy load, power is consumed during rising, and power is generated and fed back during falling. And the lifting of the cranes can not cooperate with each other, and the cranes run randomly. If the power consumption is very high when ascending at the same time, a large grid power is needed, and if the power consumption is very high when descending at the same time, the feedback energy is also huge. Therefore, enough overload allowance needs to be reserved in the wharf power utilization design, so that a plurality of cranes can operate within the allowable capacity range, and no power failure is caused. Most of the prior art solutions are developed to solve a single problem, for example, peak reduction is performed only by an energy storage device, or energy recovery is performed only by using partial feedback energy, and no integrated and synergetic comprehensive solution is formed. Under a complex wharf power grid operation scene, an overall system architecture capable of realizing multi-source data acquisition, state monitoring, intelligent judgment, strategy execution, centralized equalization and closed loop feedback is lacking. Disclosure of Invention Aiming at the defects of the prior art, the invention provides a feedback electric energy collection and load peak suppression system of a quay crane, which aims to solve the problems in the background art. The system comprises a data acquisition module, a peak power monitoring module, a feedback energy absorption module, a peak-valley scheduling module, an electric energy quality optimization module and a power balance control module. The data acquisition module is used for acquiring the instantaneous power demand Pinst, the average power Pavg, the peak duration Teak and the power growth rate Rp of the wharf power station to establish a first data set, acquiring the crane feedback power pre, the feedback duration Trec, the total feedback electric energy Erec and the real-time power consumption demand Pload to establish a second data set, acquiring the power grid peak Gu Dianjia Cpeak, cvalley, the energy storage capacity Cbat, the charge and discharge efficiency and the charge and discharge time periods Tchg and Tdis to establish a third data set, acquiring the harmonic content Hmeas, the voltage fluctuation rate Vfluc, the power factor PF and the power grid stability index Sgrid and establishing a fourth data set; The peak power monitoring module is used for extracting data of the first data set, calculating and obtaining a peak impact index PCI, comparing and analyzing with a peak impact threshold Pth, judging whether the running state of the wharf power station is stable or not, judging whether the risk of peak impact exists or not, and giving a corresponding strategy if the risk of peak impact exists; the feedback energy absorption module is used for extracting data of the second data set, calculating and obtaining a feedback absorption coefficient RAI, comparing and analyzing with a feedback absorption threshold Rth, judging whether the current feedback energy absorption condition meets the load operation requirement or not, and giving a corresponding strategy if the current feedback energy absorption condition does not meet the load operation requirement; The peak-valley scheduling module is used for extracting data of the third data set, calculating and obtaining a peak-valley switching coefficient PVI, comparing and analyzing with a switching threshold Vth, judging whether the scheduling conditions are met, and giving a scheduling strategy if the scheduling conditions are met; The power quality optimization module is used for extracting data of the fourth data set, calculating and obtaining a harmonic suppression coefficient HSI, comparing and analyzing with a harmonic suppression threshold Hth, judging whether the power quality is qualified or not, and giving a corresponding strateg