Energy-saving control system and method for battery dynamic adaptation

Abstract

The invention discloses an energy-saving control system and method for battery dynamic adaptation, and relates to the technical field of batteries, and the system comprises a DC output interface which is used for being connected with DC buses of N frequency converters; a power-type battery pack; the switching circuit is connected between the power type battery pack and the direct current output interface, and the switching circuit has a charging mode and a discharging mode; and the management unit is electrically connected with the switching circuit and is used for controlling the switching circuit to execute a charging mode or a discharging mode. Connection between the battery and the direct-current bus is achieved through the switching circuit, a single-loop and same-loop independent control structure and double-battery-pack cooperation are combined, the charging and discharging modes are flexibly switched, the energy utilization rate and the regeneration and recovery efficiency are improved, the hardware, maintenance and operation energy consumption cost is reduced, and the system is suitable for multi-elevator scenes.

Description

Technical Field

[0001] This invention relates to the field of battery technology, and in particular to an energy-saving control system and method for dynamic battery adaptation. Background Technology

[0002] Elevators, as vertical transportation tools in modern buildings, consume enormous amounts of energy during operation. This is especially true in scenarios where multiple elevators coexist, where the dynamic energy changes caused by frequent starts, stops, and braking are even more significant. During elevator operation, the motor generates a large amount of regenerative electrical energy when descending under heavy load or ascending under light load. If this energy cannot be effectively recovered and utilized, it will be dissipated as heat through the braking resistor, resulting in energy waste.

[0003] Currently, for energy management and energy-saving technologies in multi-elevator systems, the industry generally adopts energy feedback or energy storage solutions based on DC / DC converters. A typical solution involves connecting a DC / DC converter between the inverter's DC bus and the energy storage unit, and / or between the DC bus and the power grid. The DC / DC converter performs voltage conversion and power regulation to achieve the storage, reuse, or feedback of regenerative energy to the power grid.

[0004] However, these schemes using DC / DC converters have the following inherent drawbacks: energy needs to be converted twice through the DC / DC stage, resulting in significant conversion losses and reducing the overall energy efficiency of the system; DC / DC converters require additional power switches, inductors, capacitors, and heat dissipation devices, increasing system cost, size, and weight; the control strategy of bidirectional DC / DC is complex and has a high risk of failure, requiring additional protection circuits to improve reliability, further increasing system complexity and maintenance costs. Summary of the Invention

[0005] The main objective of this invention is to provide an energy-saving control system and method for dynamic battery adaptation, aiming to solve the core defects of existing energy management technologies in multi-elevator scenarios, which generally rely on DC / DC converters to achieve two-level energy regulation, resulting in low energy utilization, high maintenance costs, and high system complexity, and are unable to adapt to the dynamic operation of multiple elevators.

[0006] To achieve the above objectives, this invention proposes a battery dynamic adaptation energy-saving control system. The system includes: a DC output interface for connecting to the DC buses of N frequency converters respectively; a power battery pack; a switching circuit connected between the power battery pack and the DC output interface, the switching circuit having a charging mode and a discharging mode, used to control the power supplied to the DC output interface to output to the power battery pack to charge the power battery pack when executing the charging mode; and to control the power battery pack to output power to the DC output interface when executing the discharging mode to drive the load after inverter conversion by the frequency converter; and a management unit electrically connected to the switching circuit for controlling the switching circuit to execute the charging mode or the discharging mode.

[0007] Furthermore, the power battery pack has a positive terminal and a negative terminal, the DC output interface has a positive connection terminal and a negative connection terminal, and the switching circuit includes a first switching circuit and an input-output commutation circuit. The first switching circuit is connected between the positive terminal and the positive connection terminal of the power battery pack, and the input-output commutation circuit is connected between the negative terminal and the negative connection terminal of the power battery pack. The first switching circuit is used to close in discharge mode to form a discharge circuit, and to remain closed or open in charging mode. The input / output commutation circuit is used to form a unidirectional charging path in charging mode to allow electrical energy to flow unidirectionally into the power battery pack from the DC output interface, and to form a discharging path in discharging mode to allow electrical energy to flow out of the power battery pack to the DC output interface.

[0008] Furthermore, the system also includes: The first monitoring unit is electrically connected to the power battery pack and the management unit, and is used to monitor the voltage, temperature and status information of the power battery pack and send it to the management unit. The management unit is used to monitor the voltage, temperature, and status information of the power battery pack.

[0009] Furthermore, the first switching circuit includes a first electronic switch and a second electronic switch, which are connected in series between the positive terminal of the power battery pack and the positive connection terminal of the DC output interface. The input / output commutation circuit includes a first switching transistor and a first diode; the anode of the first diode is connected to the negative terminal of the power battery pack, and the cathode of the first diode is connected to the negative terminal of the DC output interface; the first switching transistor is connected in parallel with the first diode, and the controlled terminal of the first switching transistor is connected to the management unit. Specifically, the management unit controls the switching circuit to execute the charging mode by controlling the first switching transistor to turn off and controlling the first electronic switch and the second electronic switch to close, so that electrical energy flows from the DC output interface to the power battery pack through the first diode. The management unit controls the switching circuit to execute the discharge mode. Specifically, the management unit controls the first switching transistor to close, and controls the first electronic switch and the second electronic switch to close, so that the first diode is bypassed, and electrical energy flows from the power battery pack to the DC output interface through the first switching transistor.

[0010] Furthermore, the input / output commutation circuit includes a charging branch and a discharging branch; The charging circuit includes a charging switch and a charging diode connected in series. The anode of the charging diode is connected to the negative terminal of the power battery pack, the cathode of the charging diode is connected to one end of the charging switch, the other end of the charging switch is connected to the negative terminal of the DC output interface, and the controlled terminal of the charging switch is connected to the management unit. The discharge branch includes a discharge switch and a discharge diode connected in series. The cathode of the discharge diode is connected to the negative terminal of the DC output interface, the anode of the discharge diode is connected to one end of the discharge switch, the other end of the discharge switch is connected to the negative terminal of the power battery pack, and the controlled terminal of the discharge switch is connected to the management unit. The management unit controls the switching circuit to execute the charging mode. Specifically, the management unit controls the charging switch to close and controls the discharging switch to open, so that electrical energy flows from the DC output interface to the power battery pack through the charging branch. The management unit controls the switching circuit to execute the discharge mode. Specifically, the management unit controls the discharge switch to close and controls the charging switch to open, so that electrical energy flows from the power battery pack to the DC output interface through the discharge branch.

[0011] Furthermore, the system also includes: Energy-type battery packs, and energy-type battery packs connected in parallel with power-type battery packs; The second switching transistor is connected in series in the access circuit of the energy-type battery pack; The second monitoring unit is electrically connected to the energy-type battery pack and the management unit, and is used to monitor the status information of the energy-type battery pack. The management unit is also used to control the on / off state of the second switching transistor according to the status information of the energy-type battery pack, so as to schedule the energy-type battery pack to enter or exit the switching circuit.

[0012] Furthermore, the system also includes: Energy-type battery packs, and energy-type battery packs connected in parallel with power-type battery packs; The third switch is connected in series in the access circuit of the energy-type battery pack; The second monitoring unit is electrically connected to the energy-type battery pack and the management unit, and is used to monitor the status information of the energy-type battery pack. The management unit is also used to control the on / off state of the third switch based on the status information of the energy-type battery pack, so as to schedule the energy-type battery pack to enter or exit the switching circuit.

[0013] Furthermore, the management unit is also used to control the switching circuit and the second or third switch transistor according to the status of the power battery pack and the energy battery pack, so that the system switches between the following operating modes: safety protection mode, power battery pack single source power supply mode, energy battery pack single source power supply mode and dual-pack cooperative mode.

[0014] Furthermore, the management unit is also used for: When the system is in safety protection mode, the management unit controls the first switching circuit and the second or third switching transistor to disconnect, thereby cutting off the connection between the power battery pack and the energy battery pack and the DC output interface. When the system is in the single-source power supply mode of the power battery pack, the management unit controls the second or third switch to disconnect to isolate the energy battery pack, and controls the switching circuit to allow the power battery pack to charge or discharge independently. When the system is in the single-source power supply mode of the energy type battery pack, the management unit controls the second or third switch to close to connect the energy type battery pack, and controls the switching circuit to allow the energy type battery pack to charge the power type battery pack or discharge to the DC output interface alone. When the system is in dual-group collaborative mode, the management unit controls the second or third switch to close and controls the switching circuit to schedule the power battery pack and the energy battery pack to charge or discharge in coordination.

[0015] The present invention also proposes an energy-saving control method for dynamic battery adaptation, comprising: monitoring the system status through a management unit; When the charging conditions are met, the control switching circuit enters the charging mode: the input-output commutation circuit is configured to form a unidirectional charging path, so that electrical energy flows from the DC output interface to the power battery pack. When the discharge conditions are met, the control switching circuit enters the discharge mode: the first switching circuit is closed, and the input-output commutation circuit is configured to form a discharge path, so that electrical energy flows from the power battery pack to the DC output interface.

[0016] This invention connects the battery to the DC bus by switching circuits, and combines independent control structures for single-circuit and same-circuit circuits with the collaboration of dual battery packs to flexibly switch charging and discharging modes, improve energy utilization and regeneration efficiency, reduce hardware, maintenance and operating energy costs, and is suitable for multiple elevator scenarios. Attached Figure Description

[0017] 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.

[0018] 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.

[0019] Figure 1 This is a circuit diagram of a first embodiment of the energy-saving control system for dynamic battery adaptation of the present invention. Figure 2 This is a battery state transition diagram for a first embodiment of the energy-saving control system for dynamic battery adaptation of the present invention. Figure 3 This is a circuit diagram of a second embodiment of the energy-saving control system for dynamic battery adaptation of the present invention. Figure 4 This is a circuit diagram illustrating the mode switching between the energy-type battery pack and the power-type battery pack in Embodiment 2 of the energy-saving control system for dynamic battery adaptation of the present invention. Figure 5 This is a circuit diagram of a third embodiment of the energy-saving control system for dynamic battery adaptation of the present invention. Figure 6 The circuit diagram is for Embodiment 4 of the energy-saving control system for dynamic battery adaptation of the present invention; 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] The multi-elevator energy-saving control system includes: a DC output interface for connecting to the DC buses of N frequency converters respectively; a power battery pack; a switching circuit connected between the power battery pack and the DC output interface, which has charging and discharging modes. In charging mode, the switching circuit controls the power supplied to the DC output interface to charge the power battery pack; in discharging mode, it controls the power battery pack to output power to the DC output interface to drive the load after inverter conversion; and a management unit electrically connected to the switching circuit to control the switching circuit to execute either charging or discharging mode.

[0023] In existing multi-elevator scenarios, energy management technologies generally rely on DC / DC converters to achieve two-level energy regulation. This has core drawbacks such as low energy utilization, high maintenance costs, and high system complexity, and cannot meet the energy requirements and economic demands of dynamic operation of multiple elevators.

[0024] This invention connects the battery to the DC bus via a switching circuit. Combined with a single-circuit / same-circuit independent control structure and dual-battery pack collaboration, it flexibly switches between charging and discharging modes, improves energy utilization and regeneration efficiency, reduces hardware, maintenance and operating energy costs, and is suitable for multiple elevator yards.

[0025] Example 1 Based on this, this application proposes a battery dynamic adaptation energy-saving control system according to the first embodiment, such as... Figure 1 As shown, Figure 1 This is a circuit diagram of a first embodiment of the energy-saving control system for dynamic battery adaptation of the present invention.

[0026] The energy-saving control system for dynamic battery adaptation proposed in this application includes: a DC output interface for connecting to the DC buses of N frequency converters respectively; Power-type battery packs; The switching circuit is connected between the power battery pack and the DC output interface. The switching circuit has a charging mode and a discharging mode. When the charging mode is executed, it controls the power output of the DC output interface to the power battery pack to charge the power battery pack. When the discharging mode is executed, it controls the power battery pack to output power to the DC output interface to drive the load after the inverter is inverted. The management unit is electrically connected to the switching circuit and is used to control the switching circuit to execute charging mode or discharging mode.

[0027] Furthermore, in this example, the power battery pack has a positive terminal and a negative terminal, the DC output interface has a positive connection terminal and a negative connection terminal, and the switching circuit includes a first switching circuit and an input-output commutation circuit. The first switching circuit is connected between the positive terminal and the positive connection terminal of the power battery pack, and the input-output commutation circuit is connected between the negative terminal and the negative connection terminal of the power battery pack. The first switching circuit is used to close in discharge mode to form a discharge circuit, and to remain closed or open in charging mode. The input / output commutation circuit is used to form a unidirectional charging path in charging mode to allow electrical energy to flow unidirectionally into the power battery pack from the DC output interface, and to form a discharging path in discharging mode to allow electrical energy to flow out of the power battery pack to the DC output interface.

[0028] Furthermore, in this embodiment, the management unit integrates an energy-saving management unit and a monitoring unit.

[0029] Furthermore, the single-loop power-type energy-saving control system of this embodiment corresponds to Figure 1 The topology, components, and selections are as follows: Power Battery Pack: A power battery pack is selected. Monitoring Unit: A circuit board integrating temperature and voltage acquisition modules is used to monitor the temperature, individual cell voltage, and terminal voltage of the power battery pack in real time, and output overvoltage, undervoltage, and overtemperature alarm signals. Switch Ks: An IGBT semiconductor switch with a rated voltage of 1200V and a rated current of 20A is used to control the connection state of diode D1; Switches K1~Kn: Electromagnetic mechanical switches with a rated voltage of 500V and a rated current of 12A are used to control the DC bus switching of the frequency converter for N elevators. In this embodiment, N=2, corresponding to motor 1 and motor 2. Diode D1: A fast recovery diode with a withstand voltage of 1200V and a rated current of 30A, with unidirectional conduction from the negative terminal of the battery to the motor side. Energy Management Unit: An industrial-grade circuit board integrating CAN communication is used to collect DC bus voltage, loop current, and elevator operating status signals in real time, and to realize charging and discharging strategy control and safety protection.

[0030] Furthermore, in this embodiment, the functions and circuit connections of each component are as follows: The power battery pack serves as the energy storage core, matching the regenerative energy recovery during elevator braking and the auxiliary power supply requirements during operation through rapid charging and discharging. The monitoring unit is electrically connected to the power battery pack, uploading temperature, voltage, and alarm information to the energy management unit in real time. The energy management unit then dynamically adjusts the charging and discharging strategy to ensure capacitor safety.

[0031] The positive terminal of the power battery pack is directly connected to the common positive terminal of the DC bus of N frequency converters; the negative terminal of the power battery pack is connected to the common negative terminal of the DC bus D1 with the anode facing the negative terminal of the capacitor after being connected in series with the switch Ks and diode D1 in sequence; the DC bus of each elevator frequency converter is connected to the above common DC bus through the corresponding switch K1~Kn. In this embodiment, motor 1 corresponds to K1 and motor 2 corresponds to K2; the monitoring unit and the energy-saving management unit communicate through the CAN bus to realize data interaction.

[0032] The control logic in this embodiment is based on Figure 2 The state transition diagram is shown below: In this embodiment, the initialization phase is as follows: After the system is powered on, the energy-saving management unit first detects the working status of its own hardware, monitoring unit, and switching transistor, and simultaneously collects the voltage (V_cap), temperature (T_cap), and DC bus voltage (V_bus) of the power battery pack: If V_cap∈[360V,440V], T_cap<60℃, and there is no emergency stop or fire alarm, it is determined to be in a fault-free state and enters standby mode; in this embodiment, if both units are in maintenance state, K1 and K2 are disconnected and the system enters shutdown mode.

[0033] In this embodiment, in standby mode, the energy-saving management unit detects charging and discharging signals and alarms: if it detects an elevator braking signal or the motor is in a power generation state and there is no charging alarm, for example, V_cap<440V, T_cap<60℃, it switches to charging mode; if it detects an elevator running signal, the motor is in a power consumption state or there is no discharging alarm, for example, V_cap>360V, T_cap<60℃, it switches to discharging mode.

[0034] In this embodiment, the workflow in charging mode includes: the energy management unit detects that V_bus-V_cap > the differential voltage threshold and the capacitor is in a depleted state, for example, V_cap < 400V and the charge < 90%, and disconnects the switch Ks; due to the unidirectional conductivity of D1, the regenerative energy generated by elevator braking is fed back to the energy storage through the DC bus to D1 and D1 to the power battery pack; wherein the differential voltage threshold in this embodiment is 5V; In this embodiment, during the charging process, when V_cap≥400V and the charge ≥90%, the capacitor is in a normal state, Ks is closed to cut off D1, and it is ready to enter the discharge mode.

[0035] In this embodiment, the discharge mode workflow includes: when the energy-saving management unit detects that V_cap - V_bus > the differential voltage threshold and the capacitor is in a normal state, it keeps Ks closed. Furthermore, the power battery pack supplies power to the elevator motor via the DC bus; when V_cap≤360V (charge ≤20%, lower threshold), Ks is disconnected, D1 is reverse-cut off, the capacitor stops discharging, and damage due to power depletion is avoided.

[0036] Furthermore, in this embodiment, the switching logic between charging mode and discharging mode is as follows: In charging mode, if an elevator running signal is detected and the discharging condition is met, the system directly switches to discharging mode; in discharging mode, if an elevator braking signal is detected and the charging condition is met, the system directly switches to charging mode; in charging / discharging mode, if all elevator standby signals are detected, the system returns to standby mode.

[0037] In this embodiment, when the first elevator brakes, the energy management unit detects the power generation signal of motor 1, disconnects Ks, turns on D1, and the regenerated energy is stored in the power battery pack via the DC bus. In this embodiment, when the voltage of the power battery pack reaches 400V, Ks is closed. If the second elevator is in operation at this time, the power battery pack supplies power to the second elevator through the DC bus. In this embodiment, when the voltage of the power battery pack drops to 360V, Ks is disconnected to stop discharging and prevent the capacitor from being depleted.

[0038] The system in this embodiment achieves a regenerative energy recovery rate of ≥85% and reduces elevator operating energy consumption by more than 15% through the coordinated control of a single-loop topology and switching transistors and diodes.

[0039] Example 2 This application proposes a second embodiment of a battery dynamic adaptation energy-saving control system, such as... Figure 3 As shown, Figure 3 This is a circuit diagram of a second embodiment of the energy-saving control system for dynamic battery adaptation of the present invention.

[0040] This embodiment adds an energy-type battery pack and supporting components to the single-loop power system of Embodiment 1. The specific selection is as follows: The original components include: the power-type battery pack, monitoring unit 1, switch Ks1, diode D1, switches K1~Kn, and energy-saving management unit used in Embodiment 1; The new components include: energy-type battery pack, monitoring unit 2, and switch Ks2: The energy-type battery pack is a lithium iron phosphate battery pack, which is suitable for long-term energy storage requirements; Monitoring unit 2: adopts a monitoring circuit board with integrated BMS to collect information such as voltage, capacity, temperature, and SOC of the energy-type battery pack in real time; Switch Ks2: is an IGBT switch to control the loop connection of the energy-type battery pack.

[0041] The circuit topology in this embodiment is an extension of the single-loop power type, and the specific connection is as follows: In this embodiment, the main circuit topology is as follows: the energy-type battery pack and the power-type battery pack are connected in parallel, and their positive terminals are connected to the common positive terminal of the DC bus of N elevator frequency converters; After the negative terminal of the energy-type battery pack is connected in series with the switch Ks2, it is connected to the negative terminal circuit of the power-type battery pack, i.e., the input terminal of Ks1; the rest of the circuit is the same as in Example 1. In this embodiment, the control loop is connected as follows: the monitoring unit 2 is electrically connected to the energy-type battery pack and communicates with the energy-saving management unit via the RS485 bus to upload battery status information; the GPIO pin of the energy-saving management unit is connected to the gate of Ks2 through the driving circuit to control its on / off state.

[0042] In this embodiment, the functions of each component are as follows: Energy-type battery pack: used to provide energy support for the continuous operation of the elevator or peak-valley arbitrage, making up for the deficiency of insufficient energy storage time of power-type battery pack; Monitoring Unit 2: Used to monitor the voltage, capacity, temperature, and alarm information of the energy-type battery pack, dynamically adjust its charging and discharging strategy, ensure battery safety, and extend its lifespan; Switch Ks2: Used to control whether the energy-type battery pack is connected to the circuit by switching it on and off, and to disconnect it to isolate the battery pack in case of failure; Energy-saving management unit: A new dual-battery-pack collaborative control module has been added to monitor the status of power-type and energy-type battery packs in real time and schedule their charging and discharging behavior.

[0043] In this embodiment, the control method and state transition are as follows: The control logic of this embodiment is based on Figure 2 The state transition diagram has been updated, and a new dual-battery pack collaborative strategy has been added. In this embodiment, the initialization phase is as follows: after the system is powered on, the energy management unit simultaneously detects the status of the power battery pack and the energy battery pack; if both types of battery packs meet the requirements of "voltage ∈ [360V, 440V], temperature < 60℃", and there is no emergency stop or fire alarm, then the system enters the standby mode; if all elevators are under maintenance, K1~Kn and Ks2 are disconnected, and the system enters the shutdown mode.

[0044] In this embodiment, in standby mode, the switching mode is based on elevator status and battery alarm.

[0045] In this embodiment, the process of switching from standby mode to charging mode is as follows: when an elevator braking signal is detected and there is no charging alarm, Ks1 is disconnected, and regenerative energy is used to charge the two types of battery packs through D1. The process of switching from standby mode to discharge mode is as follows: when the elevator operation signal is detected and there is no discharge alarm, Ks1 is closed, and both types of battery packs discharge to the DC bus together.

[0046] In this embodiment, the method of dual battery pack collaborative control is as follows: when the voltage of the power battery pack is less than or equal to the first voltage threshold of the power battery pack, Ks2 is closed, the energy battery pack replenishes the power battery pack, and the elevator is powered at the same time. When the voltage of the energy type battery pack is less than or equal to the first voltage threshold of the energy type battery pack, Ks2 is disconnected, and the power type battery pack provides power from a single source while simultaneously charging the energy type battery pack with regenerative energy. In this embodiment, the modes of the energy-type battery pack and the power-type battery pack include: safety protection mode, power-type battery pack single-source power supply operation mode, energy-type battery pack single-source power supply operation mode, and dual-pack collaborative mode.

[0047] like Figure 4 As shown, Figure 4 This is a circuit diagram illustrating the mode switching between the energy-type battery pack and the power-type battery pack in Embodiment 2 of the energy-saving control system for dynamic battery adaptation of the present invention. The specific judgment logic for mode switching between the energy-type battery pack and the power-type battery pack includes: When both the energy-type battery pack and the power-type battery pack are in a low-voltage state, the system switches to safety protection mode.

[0048] The specific control process for switching to the safety protection mode is as follows: the energy-saving management unit disconnects the switching transistors Ks1 and Ks2, cuts off the connection between the dual battery pack and the DC bus; it issues an audible and visual alarm, sends a battery undervoltage signal to the elevator control cabinet, and the system is powered only by the power grid, while recording the fault status; after manual charging until the dual battery pack returns to normal, the protection mode is deactivated.

[0049] When the power battery pack is in normal operation and the energy battery pack is in low voltage operation, it switches to the single-source power supply mode of the power battery pack. The specific control process for switching to the single-source power supply mode of the power battery pack is as follows: disconnect Ks2 to isolate the energy battery pack; in standby mode, if a charging signal is detected, disconnect Ks1 and use diode D1 to preferentially charge the energy battery pack until it returns to normal; if a discharge signal is detected or the elevator is running, close Ks1 and the power battery pack supplies power to the elevator alone, while continuously monitoring the status of the energy battery pack. After it returns to normal, switch to the dual-pack collaborative mode.

[0050] When the energy-type battery pack is in normal condition and the power-type battery pack is in low-voltage condition, the system switches to a single-source power supply mode for the energy-type battery pack. The specific control process for switching to the single-source power supply mode for the power-type battery pack is as follows: close Ks2 to connect the energy-type battery pack to the circuit; open Ks1 to use the energy-type battery pack to replenish the power-type battery pack; after replenishment, keep Ks2 closed and enter the dual-pack collaborative mode.

[0051] When both battery packs are in normal condition, the system switches to dual-pack collaborative mode.

[0052] In one embodiment, the dual-group collaborative mode divides electricity prices into low, medium, and high electricity prices. The division methods include symmetrical segmentation and proportional segmentation. Specifically, the symmetrical segmentation method is as follows: let the highest electricity price of the day be Ph, the lowest electricity price be Pl, let k = Ph / Pl > 1, the current electricity price be P, and the electricity price coefficient r = P / Pl, then r ∈ [1, k]. The lower limit of the flat segment = 1 + d, the upper limit of the flat segment = kd (d is the offset, 0 < d < (k + 1) / 2), with r ∈ [1, 1 + d) as the valley segment, i.e., the low electricity price period; r ∈ [1 + d, kd) as the flat segment, i.e., the period with moderate electricity prices; and r ∈ [kd, k] as the peak segment, i.e., the period with high electricity prices.

[0053] The specific proportional division method is as follows: Let the highest electricity price of the day be Ph, the lowest electricity price be Pl, let k = Ph / Pl > 1, the current electricity price be P, and the electricity price coefficient r = P / Pl, then r ∈ [1, k]; the valley: flat: peak = "1: a: 1" interval length ratio allocation, a is the flat segment length coefficient (a ≥ 1), calculate the flat segment lower limit = 1 + (k - 1) / (2 + a), flat segment upper limit = k - (k - 1) / (2 + a), ensure that the lengths of the three segments meet the set ratio, then r ∈ [1, 1 + (k - 1) / (2 + a)] is the valley segment, that is, the low electricity price period; r ∈ [1 + (k - 1) / (2 + a), k - (k - 1) / (2 + a)] is the flat segment, that is, the electricity price period; r ∈ [k - (k - 1) / (2 + a), k] is the peak segment, that is, the high electricity price period.

[0054] Off-peak (low electricity price) charging and energy storage: When grid electricity prices are low, the system controls both power-type and energy-type battery packs to draw power from the grid simultaneously. Among them, the energy-type battery packs serve as the "main energy storage units," prioritizing the full storage of low-priced electricity; while the power-type battery packs supplement energy storage and maintain their own basic power capacity to ensure that they can respond to sudden power demands at any time.

[0055] Peak-hour (high electricity price) discharge arbitrage: When grid electricity prices rise to their peak, power purchases from the grid cease. At this time, energy-type battery packs act as the "main discharge unit," supplying power to external loads, such as factories, commercial buildings, or the grid, to obtain revenue from higher electricity prices; power-type battery packs focus on providing instantaneous power support, avoiding the lifespan loss of energy-type batteries due to frequent charging and discharging, while ensuring power supply stability.

[0056] Flexible allocation during off-peak hours (when electricity prices are moderate): The operating status of the dual battery packs is dynamically adjusted based on real-time electricity prices and load demand. If the electricity price is close to off-peak hours, the battery packs can be recharged; if it is close to peak hours, the battery packs will be used first to minimize the need for purchasing high-priced electricity.

[0057] In one embodiment, the specific control process for switching to the dual-group collaborative mode is as follows: during off-peak hours (low electricity price periods, such as 0:00-8:00): Ks2 is closed and Ks1 is opened, controlling the dual battery groups to be charged synchronously from the grid and elevator regenerated energy; among them, the energy-type battery group serves as the main energy storage unit, maintaining basic power to respond to sudden power demands.

[0058] Peak hours (high electricity price periods, such as 8:00-22:00): Close Ks2 and Ks1 to stop purchasing electricity from the grid; the energy-type battery pack serves as the main discharge unit, supplying power to the elevator or external loads to obtain high electricity revenue; the power-type battery pack focuses on providing instantaneous power support for elevator start-up and shutdown, avoiding the energy-type battery pack's lifespan loss due to frequent charging and discharging.

[0059] During off-peak hours (mid-price periods, such as 22:00-24:00): If the electricity price is close to the off-peak period, recharge the energy-type battery pack to full capacity; if the electricity price is close to the peak period, prioritize the use of dual battery packs to reduce the purchase of high-priced electricity.

[0060] In one embodiment, two elevators in an office building operate for an average of 12 hours per day. The collaborative control process is as follows: Off-peak period (0:00-8:00): The elevators are in a low-load state with less regenerative energy, and the system controls the dual battery packs to charge from the grid.

[0061] Peak hours (8:00-18:00): The elevator operates under high load. The system stops purchasing electricity from the grid. Energy-type battery packs supply power to external loads (such as factories and commercial buildings) or the grid in reverse to obtain high-priced electricity revenue. Power-type battery packs respond to the instantaneous power of elevator braking or starting.

[0062] Peak hours (18:00-22:00): Electricity price drops to 0.8 yuan / kWh, and the system is recharged to full capacity for energy-type battery packs to reserve energy for the next day's peak hours.

[0063] If the power battery pack drops to a low voltage state due to frequent charging and discharging, the system automatically switches to the energy-type single-source mode, and the energy battery pack replenishes the power, ensuring the elevator operates normally without any downtime.

[0064] Example 3 This application proposes a third embodiment of a battery dynamic adaptation energy-saving control method, such as... Figure 5 As shown, Figure 5 This is a circuit diagram of Embodiment 3 of the energy-saving control system for dynamic battery adaptation of the present invention.

[0065] This embodiment uses a co-loop topology with independent charging and discharging branches, as shown in the following connection: The main circuit topology is as follows: the positive terminal of the power battery pack is connected to the common terminal of the positive DC bus of N elevator frequency converters; The negative terminal of the power battery pack is divided into two independent branches, including a charging branch and a discharging branch. The charging branch consists of a charging switch (Kc) and a charging diode (D1) connected in series and connected to the common terminal of the negative terminal of the DC bus. The discharging branch consists of a discharging switch (Kd) and a discharging diode (D2) connected in series and connected to the common terminal of the negative terminal of the DC bus. The DC bus of the inverter of each elevator is connected to the above-mentioned common DC bus through the corresponding switches K1~Kn. In this embodiment, motor 1 corresponds to K1 and motor 2 corresponds to K2.

[0066] The control loop connection method is as follows: the energy-saving management unit is connected to the gates of Kc and Kd respectively through the drive circuit to realize independent on-off control; the charging branch and the discharging branch are connected in series with current sensors, and the output terminal is connected to the management unit to monitor the branch current in real time; the monitoring unit communicates with the energy-saving management unit through the CAN bus to upload the status information of the power battery pack.

[0067] The control logic in this embodiment is based on Figure 2 The state transition diagram is as follows: In this embodiment, the initialization phase is as follows: After the system is powered on, the energy-saving management unit performs a self-test on the hardware and collects the voltage (V_cap), temperature (T_cap), and DC bus voltage (V_bus) of the power battery pack: If V_cap∈[360V,440V], T_cap<60℃ and there is no emergency stop / fire alarm, it enters the standby mode; if all N elevators are under maintenance, K1~Kn are disconnected and the system enters the shutdown mode.

[0068] In this embodiment, in standby mode, the switching mode is based on elevator status and battery alarm.

[0069] In this embodiment, the process of switching from standby mode to charging mode is as follows: when the elevator braking signal is detected and there is no charging alarm, control Kc to close and Kd to open: the elevator regenerative energy is charged through the DC bus, Kc, D1 and the power battery pack.

[0070] In this embodiment, the process of switching from standby mode to discharge mode is as follows: when the elevator operation signal is detected and there is no discharge alarm, control Kd to close and Kc to open: the power battery pack discharges through Kd, D2 and DC bus path to supply power to the elevator.

[0071] In this embodiment, the direct switching method between charging mode, discharging mode, and standby mode is as follows: In charging or discharging mode, if a mode signal is detected from the other party, such as a running signal detected during charging, the switching transistor state is directly switched to complete the mode conversion; if a standby signal is detected, Kc and Kd are disconnected, and the system returns to standby mode; if the charging branch fails, Kc is disconnected, and only the discharging branch is kept running; if the discharging branch fails, Kd is disconnected, and only the charging branch is kept running, thus achieving fault tolerance.

[0072] Example 4 like Figure 6 As shown, Figure 6 This is a circuit diagram of Embodiment 4 of the energy-saving control system for dynamic battery adaptation of the present invention.

[0073] The circuit topology in this embodiment is an extension of the same-loop power type, and the specific connection is as follows: Main circuit topology: The energy-type battery pack ESS and the power-type battery pack are connected in parallel, and their positive terminals are connected to the common positive terminal of the DC bus of N elevator frequency converters; the negative terminal of the energy-type battery pack is connected to the negative circuit of the power-type battery pack after being connected in series with the switch Ks2, and the negative circuit of the power-type battery pack is the input terminal of Kc and Kd. The remaining circuitry is consistent with that in Embodiment 3; In this embodiment, the control loop is connected as follows: Monitoring unit 2 is electrically connected to the energy-type battery pack and communicates with the energy-saving management unit via RS485 bus to upload battery status; the energy-saving management unit is connected to the gate of Ks2 through a drive circuit to control its on / off state.

[0074] In this embodiment, the control method and the state transition method are as follows: The initialization and basic state transition conditions are as follows: After the system is powered on, the energy management unit simultaneously detects the status of the power battery pack and the energy battery pack: If both types of battery packs meet the conditions of "voltage ∈ [360V, 440V], temperature < 60℃" and there is no alarm, the system enters standby mode; If all elevators are under maintenance, disconnect K1~Kn and Ks2 to enter shutdown mode; In standby mode, the charging mode or discharging mode is switched based on the elevator status and alarm signal, which is the same as the branch control logic in Example 3. At the same time, the connection of the energy type battery pack is controlled by Ks2.

[0075] In this embodiment, the logic for determining the mode of the energy-type battery pack and the power-type battery pack is the same as in embodiment 2.

[0076] The above description is only a part of the embodiments of the present invention and does 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. A battery dynamic adaptation energy-saving control system, characterized in that, The system includes: DC output interface, used to connect to the DC bus of N frequency converters respectively; Power-type battery packs; A switching circuit is connected between the power battery pack and the DC output interface. The switching circuit has a charging mode and a discharging mode. When the charging mode is executed, the power supply connected to the DC output interface is controlled to be output to the power battery pack to charge the power battery pack. When the discharging mode is executed, the power battery pack is controlled to output power to the DC output interface to drive the load after the frequency converter inverts the power supply. A management unit, electrically connected to the switching circuit, is used to control the switching circuit to execute a charging mode or a discharging mode.

2. The energy-saving control system according to claim 1, characterized in that, The power battery pack has a positive terminal and a negative terminal, the DC output interface has a positive connection terminal and a negative connection terminal, and the switching circuit includes a first switching circuit and an input-output commutation circuit. The first switching circuit is connected between the positive terminal and the positive connection terminal of the power battery pack, and the input-output commutation circuit is connected between the negative terminal and the negative connection terminal of the power battery pack. The first switching circuit is used to close in the discharge mode to form a discharge circuit, and to remain closed or open in the charging mode. The input / output commutation circuit is used to form a unidirectional charging path in the charging mode to allow electrical energy to flow unidirectionally into the power battery pack from the DC output interface, and to form a discharging path in the discharging mode to allow electrical energy to flow out of the power battery pack to the DC output interface.

3. The energy-saving control system according to claim 2, characterized in that, The system also includes: The first monitoring unit is electrically connected to the power battery pack and the management unit, and is used to monitor the voltage, temperature and status information of the power battery pack and send it to the management unit. The management unit is used to determine the voltage, temperature, and status information of the power battery pack.

4. The energy-saving control system according to claim 3, characterized in that, The first switching circuit includes a first electronic switch and a second electronic switch, which are connected in series between the positive terminal of the power battery pack and the positive connection terminal of the DC output interface. The input / output commutation circuit includes a first switching transistor and a first diode; the anode of the first diode is connected to the negative terminal of the power battery pack, and the cathode of the first diode is connected to the negative terminal of the DC output interface; the first switching transistor is connected in parallel with the first diode, and the controlled terminal of the first switching transistor is connected to the management unit. Specifically, the management unit controls the switching circuit to execute the charging mode by controlling the first switching transistor to turn off and controlling the first electronic switch and the second electronic switch to close, so that electrical energy flows from the DC output interface to the power battery pack through the first diode. The management unit controls the switching circuit to execute the discharge mode by controlling the first switch to close, and controlling the first electronic switch and the second electronic switch to close, so that the first diode is bypassed, and electrical energy flows from the power battery pack to the DC output interface through the first switch.

5. The energy-saving control system according to claim 3, characterized in that, The input / output commutation circuit includes a charging branch and a discharging branch; The charging branch includes a charging switch and a charging diode connected in series. The anode of the charging diode is connected to the negative terminal of the power battery pack, the cathode of the charging diode is connected to one end of the charging switch, the other end of the charging switch is connected to the negative terminal of the DC output interface, and the controlled terminal of the charging switch is connected to the management unit. The discharge branch includes a discharge switch and a discharge diode connected in series. The cathode of the discharge diode is connected to the negative terminal of the DC output interface, the anode of the discharge diode is connected to one end of the discharge switch, the other end of the discharge switch is connected to the negative terminal of the power battery pack, and the controlled terminal of the discharge switch is connected to the management unit. The management unit controls the switching circuit to execute the charging mode, specifically by the management unit controlling the charging switch to close and the discharging switch to open, so that electrical energy flows from the DC output interface to the power battery pack through the charging branch. The management unit controls the switching circuit to execute the discharge mode. Specifically, the management unit controls the discharge switch to close and controls the charging switch to open, so that electrical energy flows from the power battery pack to the DC output interface through the discharge branch.

6. The energy-saving control system according to claim 4, characterized in that, The system also includes: An energy-type battery pack, wherein the energy-type battery pack is connected in parallel with the power-type battery pack; The second switch is connected in series in the access circuit of the energy-type battery pack; The second monitoring unit is electrically connected to the energy-type battery pack and the management unit, and is used to monitor the status information of the energy-type battery pack; wherein, the management unit is also used to control the on / off state of the second switching transistor according to the status information of the energy-type battery pack, so as to schedule the energy-type battery pack to enter or exit the switching circuit.

7. The energy-saving control system according to claim 5, characterized in that, The system also includes: An energy-type battery pack, wherein the energy-type battery pack is connected in parallel with the power-type battery pack; The third switch is connected in series in the access circuit of the energy-type battery pack; The second monitoring unit is electrically connected to the energy-type battery pack and the management unit, and is used to monitor the status information of the energy-type battery pack; The management unit is further configured to control the on / off state of the third switch based on the status information of the energy-type battery pack, so as to schedule the energy-type battery pack to access or exit the switching circuit.

8. The energy-saving control system according to claim 6 or 7, characterized in that, The management unit is also used to control the switching circuit and the second or third switch according to the state of the power battery pack and the energy battery pack, so that the system switches between the following operating modes: safety protection mode, power battery pack single-source power supply mode, energy battery pack single-source power supply mode and dual-pack collaborative mode.

9. The energy-saving control system according to claim 8, characterized in that, The management unit is also used for: When the system is in the safety protection mode, the management unit controls the first switching circuit and the second or third switching transistor to disconnect, thereby cutting off the connection between the power battery pack and the energy battery pack and the DC output interface. When the system is in the single-source power supply mode of the power battery pack, the management unit controls the second or third switch to disconnect to isolate the energy battery pack, and controls the switching circuit to allow the power battery pack to charge or discharge independently. When the system is in the single-source power supply mode of the energy type battery pack, the management unit controls the second or third switch to close to connect to the energy type battery pack, and controls the switching circuit to allow the energy type battery pack to charge the power type battery pack or discharge to the DC output interface alone. When the system is in the dual-group collaborative mode, the management unit controls the second or third switch to close and controls the switching circuit to schedule the power battery pack and the energy battery pack to charge or discharge in coordination.

10. A battery dynamic adaptation energy-saving control method, applied to the energy-saving control system as described in any one of claims 2 to 9, characterized in that, include: The system status is monitored through the management unit; When the charging conditions are met, the switching circuit is controlled to enter the charging mode: the input-output commutation circuit is configured to form a unidirectional charging path, so that electrical energy flows from the DC output interface to the power battery pack. When the discharge conditions are met, the switching circuit is controlled to enter the discharge mode: the first switching circuit is closed, and the input-output commutation circuit is configured to form a discharge path, so that electrical energy flows from the power battery pack to the DC output interface.

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