Energy storage buffer control method for elevator group control system and elevator group control system

Abstract

The application discloses an energy storage buffer control method for an elevator group control system and the elevator group control system, and relates to the technical field of intelligent elevators, and comprises the following steps: acquiring the inter-floor energy balance degree of a building and the health state of the energy storage device; switching between a normal control mode, a decay adaptation mode and an emergency aggregation mode according to the inter-floor energy balance degree of the building and the health state of the energy storage device; acquiring the temperature of a lithium battery cell and voltage balance, and generating a control instruction for charging and discharging actions of the energy storage device according to the switched mode, the temperature of the cell and the voltage balance. The application realizes intelligent state sensing and mode switching, so that the system can prolong the service life of the energy storage device and improve the reliability and emergency guarantee capacity.

Description

Technical Field

[0001] This invention relates to the field of intelligent elevator technology, and in particular to an energy storage buffer control method and an elevator group control system for use in elevator group control systems. Background Technology

[0002] With the increasing prevalence of green buildings and off-grid applications, independent energy systems employing "energy storage batteries + multiple elevators" have become an important solution. In such systems, the DC buses of multiple elevators are typically connected in parallel and linked to a shared energy storage device to recycle regenerated electrical energy and maintain system voltage stability. Existing conventional control strategies usually set fixed operating parameters for the energy storage system, such as a fixed state-of-charge operating range and fixed charge / discharge voltage thresholds.

[0003] This model reveals significant drawbacks in actual operation: the power fluctuations of the elevator group are drastic and random, causing the energy storage batteries to undergo frequent deep charging and discharging to balance energy, severely shortening their cycle life and making them high-cost loss components of the system; fixed parameters cannot adapt to the declining health state of the batteries as they are used, and if aging batteries continue to operate according to the original settings, their performance degradation will be accelerated, and in emergency scenarios such as power outages, the actual usable capacity is insufficient to reliably guarantee critical safety functions such as elevator entrapment rescue. Therefore, existing solutions cannot resolve the core contradiction between "long-life operation" and "high-reliability emergency response" in energy storage systems. Summary of the Invention

[0004] The main objective of this invention is to provide an energy storage buffer control method and an elevator group control system for elevator group control systems. This aims to solve the contradiction between the severely shortened lifespan and insufficient emergency support capabilities of energy storage systems equipped for elevator groups in environments without a power grid or with a weak power grid, due to unreasonable operating modes.

[0005] To achieve the above objectives, this invention proposes an energy storage buffer control method for a group control system of elevators. The group control system of elevators includes an energy storage device and multiple elevators. The energy storage device is electrically connected to a common DC bus of the multiple elevators. The method includes: To obtain the energy balance of building stairwells and the health status of energy storage devices; Based on the energy balance of the building's stairwells and the health status of the energy storage devices, the system switches between normal control mode, attenuation adaptation mode, and emergency aggregation mode. The system acquires the temperature and voltage balance of the lithium battery cells and generates control commands for the charging and discharging of the energy storage device based on the switched mode, cell temperature, and voltage balance.

[0006] Furthermore, the health status is characterized by the degree of cycle life degradation of the energy storage device and / or the highest temperature of the battery cell.

[0007] Furthermore, the method also includes setting charge and discharge action thresholds associated with the common DC bus voltage, the charge and discharge action thresholds including a charging action voltage threshold higher than the bus rated voltage and a discharging action voltage threshold lower than the bus rated voltage.

[0008] Furthermore, when the system is operating in normal control mode, the methods include: A first state-of-charge target operating range is set for the energy storage device, and a first charging action voltage threshold and a first discharging action voltage threshold are set for the common DC bus. When the energy balance in the elevator shaft is detected to be out of balance and exceeds the preset threshold, if the real-time voltage of the common DC bus exceeds the first charging action voltage threshold, the energy storage device is controlled to perform a charging action. If the real-time voltage is lower than the first discharge action voltage threshold, the energy storage device is controlled to perform a discharge action.

[0009] Furthermore, the switching between modes also includes: when the cycle life decay indicated by the health status exceeds a preset decay threshold, switching to decay adaptation mode; In the attenuation adaptation mode, the target operating range of the energy storage device's state of charge is narrowed from the first target operating range to the second target operating range; the first charging action voltage threshold is increased, and / or the first discharging action voltage threshold is decreased.

[0010] Furthermore, compared to the first state of charge target operating range, the upper limit of the second state of charge target operating range is lowered and / or the lower limit is raised.

[0011] Furthermore, the generation of control commands also includes: The charging and discharging thresholds are dynamically adjusted based on the cell temperature. When the cell temperature exceeds the preset safe temperature, the discharge action voltage threshold is increased and / or the charging action voltage threshold is decreased to limit the charging and discharging power of the energy storage device.

[0012] Furthermore, the generation of control commands also includes the use of segmented power control: When the operating status parameters exceed the charging and discharging action threshold but do not reach the first critical value, the energy storage device is controlled to charge and discharge at the first power level. When the operating status parameters exceed the first critical value but do not reach the second critical value, charging and discharging are performed at the second power level, which is higher than the first power level. When the operating status parameters exceed the second critical value, charging and discharging are performed at the maximum safe power level.

[0013] Furthermore, switching between modes also includes: When a preset emergency scenario is detected, switch to emergency aggregation mode; In emergency aggregation mode, all elevators are controlled to aggregate the regenerative power generated during their operation to a common DC bus, and the aggregated power is preferentially allocated to elevators performing emergency rescue missions.

[0014] The present invention also proposes an energy group control system for an elevator, characterized in that the system includes: a multi-agent scheduling layer, a multi-dimensional perception layer, a simplified energy storage buffer layer, a loss feedback layer, and an elevator; A multi-dimensional perception layer is used to collect real-time data on pedestrian flow within the building, the operating status of multiple elevators, and the energy storage status of energy storage devices. The multi-agent scheduling layer is used to construct each elevator as an independent agent based on passenger flow data, operation status data and energy storage status data. Through collaborative decision-making among independent agents, roles are dynamically assigned to each elevator and scheduling instructions are generated to schedule the electrical energy generated by elevators in regenerative power generation mode to elevators in electric operation mode. A minimalist energy storage buffer layer is used to implement an energy storage buffer control method for elevator group control systems. When the energy balance between the elevators in the regenerative power generation mode and the electric operation mode exceeds the preset threshold for dynamic adjustment, charging and discharging are initiated. The loss feedback layer is used to monitor the loss data of the core components of each elevator in real time and feed it back to the multi-agent scheduling layer. Based on the loss data, the multi-agent scheduling layer introduces loss constraints when allocating roles and generating scheduling instructions.

[0015] This invention enables the system to extend its energy storage lifespan and improve its reliability and emergency response capabilities through intelligent state perception and mode switching. Furthermore, in the event of a grid outage and insufficient energy storage, an emergency energy aggregation mechanism can prioritize the use of all elevator regenerated power for rescue operations, fundamentally resolving the core contradiction between short energy storage lifespan and unreliable emergency response in grid-free scenarios. Attached Figure Description

[0016] The accompanying drawings, which are incorporated in and form part of this specification, illustrate embodiments consistent with the invention and, together with the description, serve to explain the principles of the invention.

[0017] To more clearly illustrate the technical solutions in the embodiments of the present invention or the prior art, the drawings used in the description of the embodiments or the prior art will be briefly introduced below. Obviously, for those skilled in the art, other drawings can be obtained based on these drawings without creative effort.

[0018] Figure 1 This is a schematic flowchart illustrating the energy storage buffer control method for a group control system of elevators according to the present invention. Figure 2 This is a schematic diagram of the modular structure of the elevator energy group control system.

[0019] The objectives, features, and advantages of this invention will be further explained in conjunction with the embodiments and with reference to the accompanying drawings. Detailed Implementation

[0020] It should be understood that the specific embodiments described herein are merely illustrative of the technical solutions of the present invention and are not intended to limit the present invention.

[0021] To better understand the technical solution of the present invention, a detailed description will be provided below in conjunction with the accompanying drawings and specific embodiments.

[0022] like Figure 1 As shown, Figure 1 This is a schematic flowchart of the energy storage buffer control method for elevator group control system provided by the present invention.

[0023] This invention proposes an energy storage buffer control method for a group control system of elevators. The group control system of elevators includes an energy storage device and multiple elevators. The energy storage device is electrically connected to a common DC bus of the multiple elevators. The method includes: S10, obtain the energy balance of the building's stairwells and the health status of the energy storage devices; The acquisition of energy balance within the elevator shaft relies on real-time monitoring of the system's energy flow by a multi-dimensional sensing layer. This sensing layer synchronously collects the DC-side current of each elevator inverter connected to the common DC bus at a sampling frequency of no less than 100Hz, and monitors the real-time voltage of the common DC bus. Based on this data, the central control unit calculates the product of the sum of the currents of all elevators at the same moment and the bus voltage to obtain the real-time net power value of the system. The sign and amplitude of this net power value directly and dynamically reflect the instantaneous supply and demand relationship of power generation and consumption among the elevators in the building, thus constituting the core quantitative indicator of energy balance within the elevator shaft.

[0024] Meanwhile, the health status of the energy storage device is continuously monitored and evaluated through its built-in battery management system. The energy storage device is, for example, a 200kWh / 700VDC lithium iron phosphate battery pack, which integrates a complete sensor network: including high-precision Hall sensors (sampling frequency not less than 10Hz) for monitoring the total voltage and current of the battery pack, acquisition harnesses for synchronously acquiring the voltage of all series-connected cells to achieve equalization analysis, and a distributed array of temperature sensors. Based on this, the battery management system adopts a fusion strategy using the ampere-hour integration method as the primary method and the open-circuit voltage method for periodic calibration to estimate a real-time state of charge (SOC) value with a resolution of 1%. By analyzing complete charge-discharge segments during historical operation, the system calculates the current actual usable capacity of the battery, compares it with the rated capacity, and derives a quantified health status value, which corely characterizes the degree of cycle life degradation (e.g., SOH = 75%). Real-time SOC, SOH, maximum cell temperature, and voltage equalization data are reported to the central control unit in real time via a communication bus.

[0025] S20 switches between normal control mode, attenuation adaptation mode and emergency aggregation mode based on the energy balance of the building's stairwells and the health status of the energy storage device. In this embodiment, the system is in normal control mode by default for most of its normal operation time. In this mode, the system sets the first state of charge target operating range ([30%, 70%) when SOH≥80% and narrows it to [35%, 65%] when 60%≤SOH<80%). Based on the preset mapping relationship (for example, when SOH≥80%, the target operating range of SOC is set to [30%, 70%]; when SOH≥80%, it is narrowed to [35%, 65%]), and sets the corresponding first charging action voltage threshold and first discharging action voltage threshold for the energy storage device in combination with the current SOH (e.g., 75%).

[0026] When the health status (e.g., SOH) of the energy storage device is detected to decrease and exceed a preset degradation threshold (e.g., from 80% to 60%), the system automatically switches from normal control mode to degradation adaptation mode. In this mode, the core of the control strategy shifts to protecting the aging battery. Key actions include: further narrowing the target SOC operating range from the aforementioned first range (e.g., narrowing it to [40%, 60%]); and simultaneously increasing the charging action voltage threshold and / or decreasing the discharging action voltage threshold based on pre-stored dynamic adjustment rules, thereby relaxing the voltage conditions for triggering energy storage actions and reducing its operating frequency.

[0027] When the multi-dimensional perception layer detects a preset emergency scenario (e.g., power outage and energy storage SOC below the minimum safety threshold, or receiving an elevator entrapment rescue command), the system immediately switches to the highest priority emergency aggregation mode. The core objective of this mode is to ensure critical safety functions; strategically, it ignores optimization of energy storage lifespan and instead mobilizes the energy resources of the entire system.

[0028] S30 acquires the temperature and voltage balance of the lithium battery cells, and generates control commands for the charging and discharging of the energy storage device based on the switched mode, cell temperature and voltage balance.

[0029] In this embodiment, the highest cell temperature and voltage balance data of the energy storage device are continuously obtained from the battery management system. Based on the current mode, these safety parameters and bus status are combined to generate the final control command.

[0030] In normal control mode or attenuation adaptation mode: the real-time voltage of the common DC bus is continuously compared with the charging and discharging action threshold of the current mode. If the bus voltage exceeds the charging threshold, a charging command is generated; if it is lower than the discharging threshold, a discharging command is generated; if it is between the two, a standby command is generated. While generating the above commands, the cell temperature is simultaneously determined. If the maximum temperature exceeds the preset safe temperature (e.g., 45℃), the charging and discharging action threshold is dynamically corrected (e.g., increasing the discharging threshold), thereby generating correction commands that limit charging and discharging power or prohibit operation to prevent thermal runaway. When executing charging and discharging actions, a segmented power control strategy is further used to generate commands of different power levels based on the degree to which the bus voltage deviates from the threshold. For example, when the voltage exceeds the threshold but does not reach the first critical value, a "low power charging / discharging" command is generated; when it exceeds the first critical value but does not reach the second critical value, a "medium power charging / discharging" command is generated; when it severely exceeds the threshold, a "maximum safe power charging / discharging" command is generated.

[0031] In emergency aggregation mode, the logic for generating control commands undergoes a fundamental change: the highest priority scheduling command is sent to all elevator frequency converters, forcing them to enter the "energy contribution" state to maximize the aggregation of regenerated power to the common DC bus; power-oriented distribution commands are generated to ensure that all power collected by the bus is supplied to elevators performing emergency rescue missions preferentially and continuously; the bus voltage and energy storage status are continuously monitored, and if necessary, commands are generated to cut off non-critical loads to ensure the stability of rescue energy supply.

[0032] like Figure 2 As shown, Figure 2 This is a schematic diagram of the modular structure of the elevator energy group control system.

[0033] Reference Figure 2The present invention also proposes an elevator energy group control system, comprising: a multi-agent scheduling layer 10, a multi-dimensional perception layer 20, a simplified energy storage buffer layer 30, a loss feedback layer 40, and an elevator 50, wherein each layer forms a real-time data closed loop. The multi-dimensional perception layer 20 is used to collect real-time data on pedestrian flow in the building, the operating status data of multiple elevators 50, and the energy storage status data of the energy storage device 31. The multi-agent scheduling layer 10 is used to construct each elevator 50 as an independent intelligent agent based on passenger flow data, operation status data and energy storage status data. The core control unit 11 of the multi-agent scheduling layer 10 controls the collaborative decision-making among the intelligent agents, dynamically assigns roles to each elevator 50 and generates scheduling instructions, so that the electrical energy generated by the elevator 50 in the regenerative power generation mode is preferentially scheduled to the elevator 50 in the electric operation mode. The minimalist energy storage buffer layer 30 includes an energy storage device 31, which is used to initiate charging and discharging for buffering only when the energy supply and demand imbalance between the regenerative power generation mode and the electric operation mode exceeds a preset threshold for dynamic adjustment. The loss feedback layer 40 is used to monitor the loss data of the core components of each elevator 50 in real time and feed it back to the multi-agent scheduling layer 10 so as to allocate roles and scheduling instructions based on loss constraints.

[0034] The above are only some embodiments of the present invention and do not limit the patent scope of the present invention. All equivalent structural transformations made under the technical concept of the present invention using the contents of the present invention specification and drawings, or direct / indirect applications in other related technical fields, are included within the patent protection scope of the present invention.

Claims

1. An energy storage buffer control method for a group control system of elevators, characterized in that, The elevator group control system includes an energy storage device and multiple elevators. The energy storage device is electrically connected to a common DC bus of the multiple elevators. The method includes: Obtain the energy balance of the building's stairwells and the health status of the energy storage device; Based on the energy balance of the building's stairwells and the health status of the energy storage device, the system switches between normal control mode, attenuation adaptation mode, and emergency aggregation mode. The temperature and voltage balance of the lithium battery cells are obtained, and control commands for charging and discharging the energy storage device are generated based on the switched mode, the cell temperature, and the voltage balance.

2. The method according to claim 1, characterized in that, The health status is characterized by the degree of cycle life decay of the energy storage device and / or the highest temperature of the battery cell.

3. The method according to claim 1, characterized in that, The method further includes setting charge and discharge action thresholds associated with the common DC bus voltage, the charge and discharge action thresholds including a charging action voltage threshold higher than the bus rated voltage and a discharging action voltage threshold lower than the bus rated voltage.

4. The energy storage buffer control method for a group control system of elevators according to claim 1, characterized in that, When the system is operating in the normal control mode, the method includes: A first state-of-charge target operating range is set for the energy storage device, and a first charging action voltage threshold and a first discharging action voltage threshold are set for the common DC bus. When the energy balance imbalance in the elevator shaft exceeds a preset threshold, if the real-time voltage of the common DC bus exceeds the first charging action voltage threshold, the energy storage device is controlled to perform a charging action. If the real-time voltage is lower than the first discharge action voltage threshold, then the energy storage device is controlled to perform a discharge action.

5. The method according to claim 4, characterized in that, The switching between modes also includes: when the degree of cycle life decay indicated by the health status exceeds a preset decay threshold, switching to decay adaptation mode; In the attenuation adaptation mode, the target operating range of the state of charge of the energy storage device is narrowed from the first target operating range of the state of charge to the second target operating range of the state of charge; the first charging action voltage threshold is increased, and / or the first discharging action voltage threshold is decreased.

6. The method according to claim 5, characterized in that, Compared to the first state of charge target operating range, the upper limit of the second state of charge target operating range is lower and / or the lower limit is higher.

7. The method according to claim 3, characterized in that, The generation control instructions also include: The charging and discharging threshold is dynamically adjusted based on the cell temperature. When the cell temperature exceeds a preset safe temperature, the discharge action voltage threshold is increased and / or the charging action voltage threshold is decreased to limit the charging and discharging power of the energy storage device.

8. The method according to claim 3, characterized in that, The generated control commands also include segmented power control: When the operating status parameter exceeds the charging / discharging action threshold but does not reach the first critical value, the energy storage device is controlled to charge and discharge at the first power level. When the operating status parameter exceeds the first critical value but does not reach the second critical value, charging and discharging are performed at a second power level higher than the first power level. When the operating status parameter exceeds the second critical value, charging and discharging are performed at the maximum safe power level.

9. The method according to claim 1, characterized in that, The switching between modes also includes: When a preset emergency scenario is detected, switch to emergency aggregation mode; In the emergency aggregation mode, all elevators are controlled to aggregate the regenerative power generated during their operation to the common DC bus, and the aggregated power is preferentially allocated to elevators performing emergency rescue tasks.

10. An energy group control system for elevators, characterized in that, The system includes: a multi-agent scheduling layer, a multi-dimensional perception layer, a simplified energy storage buffer layer, a loss feedback layer, and an elevator; A multi-dimensional perception layer is used to collect real-time data on pedestrian flow within the building, the operating status of multiple elevators, and the energy storage status of energy storage devices. The multi-agent scheduling layer is used to construct each elevator as an independent agent based on the pedestrian flow data, operation status data and energy storage status data, and dynamically assign roles to each elevator and generate scheduling instructions through collaborative decision-making among the independent agents, so as to schedule the electrical energy generated by the elevator in the regenerative power generation mode to the elevator in the electric operation mode. A minimalist energy storage buffer layer is used to perform the method as described in any one of claims 1-9, initiating charging and discharging when the energy imbalance between the regenerative power generation mode and the electric operation mode exceeds a preset threshold for dynamic adjustment; The loss feedback layer is used to monitor the loss data of the core components of each elevator in real time and feed it back to the multi-agent scheduling layer. Based on the loss data, the multi-agent scheduling layer introduces loss constraints when allocating roles and generating scheduling instructions.

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