Elevator battery energy storage power supply device

Abstract

The utility model discloses an elevator battery energy storage power supply device, comprising: a charger, an elevator drive unit, a battery stack, a variable structure switch, and an overcurrent protection unit. The elevator battery energy storage power supply device can charge the battery energy storage power supply device when the city power grid is at a valley electricity price, and use the battery energy storage power supply device to provide energy to the elevator when the city power grid is at a peak electricity price. The elevator battery energy storage power supply device can also store the electricity generated by the elevator traction machine in the power generation state into the battery energy storage power supply device, and can also store low-priced electricity in the battery stack during the valley period of the power grid.

Description

Technical Field

[0001] The embodiments of the utility model relate to a power electronic conversion technology and a battery energy storage technology, and in particular to the fields of converters, battery energy storage, elevator drives, etc. Background Art

[0002] Elevators are both ancient and young means of transporting people, providing vertical transportation services for humans. Based on the development of various technologies, especially power electronics technology, elevators have made great improvements in control and rideability. With the increasing requirements for energy conservation and emission reduction in modern society, people have begun to focus on the energy conservation of elevator operation. By adding energy storage devices to the elevator drive link, elevator energy conservation can be achieved to a certain extent. When the weight of the elevator car side is greater than the weight of the counterweight side, the elevator traction machine is working in a power generation state when it is descending, and its electric energy flows back to the DC bus through the drive converter. Traditional elevators consume this part of energy by connecting a brake resistor in parallel, otherwise the DC bus voltage will increase, causing accidents. The principle of the elevator energy storage device is to connect an energy storage device in parallel to the DC bus, which stores the electric energy output by the traction machine instead of using a brake resistor to consume it. The energy stored in the energy storage device is returned to the DC bus at an appropriate time, and in this way the elevator operates in an energy-saving manner.

[0003] Due to the complex working conditions of elevators and energy storage devices, the elevators rise and fall, the car load conditions change unpredictably, and the state of charge (SOC) of the energy storage device changes dynamically with the working time. The complex working conditions make it difficult to determine the working state of the elevator energy storage device, which makes it difficult to control. In addition, the current research on adding energy storage devices to elevators only focuses on the energy storage devices of a single elevator. In fact, with the trend of large-scale and high-rise buildings, the situation of multiple elevators in one building is the mainstream trend. If each elevator is equipped with a set of energy storage devices, it is obviously not able to adapt to the development and progress of the times. Utility Model Content

[0004] The embodiment of the utility model proposes an inverter device and a control method thereof, which can store the electric energy generated by the traction machine when it is in a power generation state in a battery stack, and can also store low-cost electric energy in the battery stack during the off-peak period of the power grid.

[0005] The utility model discloses an elevator battery energy storage power supply device, comprising:

[0006] Battery charger;

[0007] Elevator drive unit;

[0008] Battery stack;

[0009] Variable structure switch;

[0010] Overcurrent protection unit;

[0011] in:

[0012] The elevator drive unit includes a voltage sensor, a current sensor and n frequency converters, each frequency converter drives a traction machine; the frequency converter input terminals are respectively connected to the city grid to obtain electric energy from the city grid; the frequency converter is provided with a DC bus, and the DC bus is connected in parallel with the common bus of the elevator drive unit;

[0013] The charger provides charging current to the battery stack; the battery stack has a + terminal and a - terminal, and the + terminal and the - terminal of the battery stack are respectively connected to the + terminal and the - terminal of the common bus of the elevator drive unit through the variable structure switch and the overcurrent protector;

[0014] The variable structure switch is controlled according to the state of the municipal power grid and the peak and valley electricity price time;

[0015] The variable structure switch is controlled according to the voltage and current sensor of the elevator drive unit;

[0016] The overcurrent protection unit is activated when the current of the elevator drive unit exceeds a set threshold value, and disconnects the battery stack from the common bus.

[0017] The variable structure switch includes a first switch, a second switch, a current limiting resistor, and a circuit breaker; the circuit breaker includes third and fourth switch contacts; the first switch is connected in series with the current limiting resistor and in parallel with the second switch, and one end of the first switch is connected to the + end of the battery stack, and the other end is connected to one end of the third switch contact connected to the circuit breaker; the other end of the third switch contact of the circuit breaker is connected to the + end of the common bus of the elevator drive unit, and one end of the fourth switch contact of the circuit breaker is connected to the - end of the battery stack, and the other end is connected to the - end of the common bus of the elevator drive unit.

[0018] The battery stack includes a battery management system and m battery modules. The battery modules are connected in series, the + end of the first battery module is the + end of the battery stack, and the - end of the last battery module is the - end of the battery stack.

[0019] The battery module includes a battery module management system and k single cells, each of which is connected in series, the + end of the first single cell is the + end of the battery module, and the - end of the last single cell is the - end of the battery module.

[0020] The single cell is composed of a positive electrode, a separator, a negative electrode, a polyoxymethylene solid electrolyte and packaging materials. The polyoxymethylene solid electrolyte is formed by injecting an electrolyte containing trioxymethylene into a battery cell and solidifying it in situ in the battery cell at 20-60°C. The polyoxymethylene in the polyoxymethylene solid electrolyte has a special micro-nano structure, which can confine the electrolyte inside the micro-nano structure and prevent it from flowing freely.

[0021] In the solid-state lithium-ion battery and sodium-ion battery containing polyoxymethylene, there is no freely flowing liquid electrolyte in the battery core.

[0022] The structure change rule of the first switch, the second switch, the current limiting resistor, the third and fourth switch contacts of the variable structure switch is:

[0023] When the common bus voltage of the elevator drive unit is higher than the battery stack voltage, the circuit breaker is turned on, the third and fourth switch contacts are energized, the first switch is turned on, the current is limited by the current limiting resistor, and the common bus voltage decreases over time. When the common bus voltage is equal to the battery stack voltage, the first switch is disconnected, the second switch is turned on, the battery stack is directly connected to the common bus, and the common bus charges the battery stack;

[0024] When the common bus voltage of the elevator drive unit is lower than the battery stack voltage, the circuit breaker is turned on, the third and fourth switch contacts are energized, the first switch is turned on, the current is limited by the current limiting resistor, and the common bus voltage rises over time. When the common bus voltage is equal to the battery stack voltage, the first switch is disconnected and the second switch is turned on. The battery stack is directly connected to the common bus, and the battery stack provides electrical energy for the elevator drive unit.

[0025] When the mains power grid is in the off-peak power supply period, the charger charges the battery stack, and the elevator drive unit is supplied with power by the mains power grid; when the mains power grid is in the peak power supply period, the charger stops charging the battery stack, and the elevator drive unit is supplied with power by the battery stack instead.

[0026] The battery stack voltage is consistent with the common bus voltage of the elevator drive unit.

[0027] The elevator battery energy storage and power supply device also includes a remote communication unit. BRIEF DESCRIPTION OF THE DRAWINGS

[0028] Figure 1 This is a schematic diagram of a first application example of an elevator battery energy storage and power supply device of the utility model;

[0029] Figure 2 This is a schematic diagram of the variable structure switch structure of the utility model;

[0030] Figure 3 This is a schematic diagram of the battery stack structure of the utility model;

[0031] Figure 4 This is the structural intention of the battery module of the utility model;

[0032] Figure 5 This is a schematic diagram of the current limiting mode of the variable structure switch of the utility model;

[0033] Figure 6 This is a schematic diagram of the conduction mode of the variable structure switch of the utility model;

[0034] Figure 7 This is a schematic diagram of the change of the voltage of the common bus when the battery stack of the utility model supplies power to the common bus and the variable structure switch is in the current limiting mode;

[0035] Figure 8 This is a schematic diagram of the change in voltage of the common bus bar when the utility model traction machine generates electricity and the common bus bar charges the battery stack, and the variable structure switch is in the current limiting mode;

[0036] Fig. 9 This is a schematic diagram of a second application example of an elevator battery energy storage and power supply device of the utility model. DETAILED DESCRIPTION

[0037] In order to make the purpose, technical solution and advantages of the embodiments of the present application clearer, the technical solution in the embodiments of the present application will be clearly and completely described below in conjunction with the drawings in the embodiments of the present application. Obviously, the described embodiments are part of the embodiments of the present application, not all of the embodiments. Based on the embodiments in the present application, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of this application.

[0038] It should be noted that when a component is said to be "fixed to" another component, it can be directly on another component or there can be a central component. When a component is said to be "connected to" another component, it can be directly connected to another component or there can be a central component at the same time.

[0039] Unless otherwise defined, all technical and scientific terms used herein have the same meaning as those commonly understood by those skilled in the art to which this application belongs. The terms used herein in the specification of this application are only for the purpose of describing specific embodiments and are not intended to limit this application. The term "and / or" used herein includes any and all combinations of one or more of the related listed items.

[0040] In order to at least partially solve the problems existing in the prior art, for example, how to solve the problem of difficulty in controlling the charging of the battery stack by the power grid or the traction machine. The embodiment of the utility model provides an elevator battery energy storage and power supply device, wherein the elevator battery energy storage and power supply device comprises:

[0041] Battery charger;

[0042] Elevator drive unit;

[0043] Battery stack;

[0044] Variable structure switch;

[0045] Overcurrent protection unit;

[0046] in:

[0047] The elevator drive unit includes a voltage sensor, a current sensor and n frequency converters, each frequency converter drives a traction machine; the frequency converter input terminals are respectively connected to the city grid to obtain electric energy from the city grid; the frequency converter is provided with a DC bus, and the DC bus is connected in parallel with the common bus of the elevator drive unit;

[0048] The charger provides charging current to the battery stack; the battery stack has a + terminal and a - terminal, and the + terminal and the - terminal of the battery stack are respectively connected to the + terminal and the - terminal of the common bus of the elevator drive unit through the variable structure switch and the overcurrent protector;

[0049] The variable structure switch is controlled according to the state of the municipal power grid and the peak and valley electricity price time;

[0050] The variable structure switch is controlled according to the voltage and current sensor of the elevator drive unit;

[0051] The overcurrent protection unit is activated when the current of the elevator drive unit exceeds a set threshold value, and disconnects the battery stack from the common bus.

[0052] The variable structure switch includes a first switch, a second switch, a current limiting resistor, and a circuit breaker; the circuit breaker includes third and fourth switch contacts; the first switch is connected in series with the current limiting resistor and in parallel with the second switch, and one end of the first switch is connected to the + end of the battery stack, and the other end is connected to one end of the third switch contact connected to the circuit breaker; the other end of the third switch contact of the circuit breaker is connected to the + end of the common bus of the elevator drive unit, and one end of the fourth switch contact of the circuit breaker is connected to the - end of the battery stack, and the other end is connected to the - end of the common bus of the elevator drive unit.

[0053] The battery stack includes a battery management system and m battery modules. The battery modules are connected in series, the + end of the first battery module is the + end of the battery stack, and the - end of the last battery module is the - end of the battery stack.

[0054] The battery module includes a battery module management system and k single cells, each of which is connected in series, the + end of the first single cell is the + end of the battery module, and the - end of the last single cell is the - end of the battery module.

[0055] The monomer battery is a solid-state lithium-ion battery and a sodium-ion battery containing polyformaldehyde. The solid-state lithium-ion battery and the sodium-ion battery containing polyformaldehyde are composed of a positive electrode, a separator, a negative electrode, a polyformaldehyde solid electrolyte and a packaging material. The polyformaldehyde solid electrolyte is formed by injecting an electrolyte containing trioxymethylene into a battery cell and solidifying it in situ in the battery cell at 20-60°C.

[0056] The structure change rule of the first switch, the second switch, the current limiting resistor, the third and fourth switch contacts of the variable structure switch is:

[0057] When the common bus voltage of the elevator drive unit is higher than the battery stack voltage, the circuit breaker is turned on, the third and fourth switch contacts are energized, the first switch is turned on, the current is limited by the current limiting resistor, and the common bus voltage decreases over time. When the common bus voltage is equal to the battery stack voltage, the first switch is disconnected, the second switch is turned on, the battery stack is directly connected to the common bus, and the common bus charges the battery stack.

[0058] When the common bus voltage of the elevator drive unit is lower than the battery stack voltage, the circuit breaker is turned on, the third and fourth switch contacts are energized, the first switch is turned on, the current is limited by the current limiting resistor, and the common bus voltage rises over time. When the common bus voltage is equal to the battery stack voltage, the first switch is disconnected and the second switch is turned on. The battery stack is directly connected to the common bus, and the battery stack provides electrical energy for the elevator drive unit.

[0059] When the mains power grid is in the off-peak power supply period, the charger charges the battery stack, and the elevator drive unit is supplied with power by the mains power grid; when the mains power grid is in the peak power supply period, the charger stops charging the battery stack, and the elevator drive unit is supplied with power by the battery stack instead.

[0060] The battery stack voltage is consistent with the common bus voltage of the elevator drive unit.

[0061] The elevator battery energy storage and power supply device also includes a remote communication unit.

[0062] Figure 1 This is a schematic diagram of a first application example of an elevator battery energy storage and power supply device of the utility model. Figure 1The elevator battery energy storage and power supply device comprises a charger 1, an elevator drive unit 2, a battery stack 3, a variable structure switch 4, and an overcurrent protection unit 5.

[0063] The charger 1 uses the industrial frequency AC power of the city power grid to charge the battery stack 3. The + end of the battery stack 3 is connected to the + end of the common bus of the elevator drive unit 2 through the variable structure switch 4 and the overcurrent protection unit 5, and the - end of the battery stack 3 is connected to the - end of the common bus of the elevator drive unit 2 through the variable structure switch 4 and the overcurrent protection unit 5.

[0064] The elevator drive unit 2 includes n frequency converters 21, each of which drives a traction machine. The frequency converter includes a +DC bus terminal and a -DC bus terminal, and all the +DC bus terminals and -DC bus terminals of the frequency converters are respectively connected to the + terminal and the - terminal of the common bus. The elevator drive unit 2 includes a plurality of voltage sensors 22 and current sensors 23 for detecting the working condition of the elevator drive unit, and the outputs of the voltage sensors 22 and current sensors 23 can be used to control the variable structure switch 4. The city power grid provides power to the frequency converter.

[0065] Figure 2 This is a schematic diagram of the variable structure switch structure of the utility model. Figure 2 , the variable structure switch includes a first switch 41, a second switch 42, a current limiting resistor 43, and a circuit breaker 44. The circuit breaker 44 includes a third switch contact 441 and a fourth switch contact 442. After the first switch 41 is connected in series with the current limiting resistor 43 and in parallel with the second switch 42, one end is connected to the battery stack 3+ end, and the other end is connected to one end of the third switch contact 441 of the circuit breaker. The other end of the third switch contact 441 of the circuit breaker is connected to the common bus + end of the elevator drive unit. One end of the fourth switch contact 442 of the circuit breaker is connected to the battery stack 3- end, and the other end is connected to the common bus - end of the elevator drive unit 2.

[0066] Figure 3 This is a schematic diagram of the structure of the battery stack 3 of the utility model. Figure 3 The battery stack 3 includes a battery management system 31 and m battery modules 32. The battery modules 32 are connected in series, the + end of the first battery module is the + end of the battery stack, and the - end of the last battery module is the - end of the battery stack.

[0067] Figure 4 This is the battery module structure of the utility model. Figure 4 As shown, the battery module 32 includes a battery module management system 321 and k single cells 322. Each single cell is connected in series, the + end of the first single cell is the + end of the battery module 32, and the - end of the last single cell is the - end of the battery module 32.

[0068] Figure 5 It is a schematic diagram of the current limiting mode of the variable structure switch 4 of the utility model. Figure 6 This is a schematic diagram of the conduction mode of the variable structure switch of the utility model. Figure 7 This is a schematic diagram of the common bus voltage change when the battery stack 3 of the utility model is in the common bus power supply working condition and the variable structure switch is in the current limiting mode. Figure 5 As shown, during the variable structure switch current limiting mode, the circuit breaker 44 is turned on, the third switch contact 441 and the fourth switch contact 442 are energized, and the first switch 41 is turned on. The current is limited by the current limiting resistor 43, and the common bus voltage is as follows: Figure 7 When the common bus voltage is equal to the battery stack voltage, the variable structure switch 4 enters the state as shown in FIG. Figure 6 During the variable structure switch conduction mode, the first switch 41 is disconnected, the second switch 42 is turned on, the battery stack is directly connected to the common bus, and the battery stack provides power for the elevator drive unit.

[0069] Figure 8 The diagram is a schematic diagram of the common bus voltage change when the traction machine generates electricity and the common bus charges the battery stack, and the variable structure switch is in the current limiting mode. When the common bus voltage is higher than the battery stack voltage, the circuit breaker 44 is turned on, and the third switch contact 441 and the fourth switch contact 442 are turned on. When the first switch 41 is turned on, the variable structure switch enters the state as shown in FIG. Figure 5 The current limiting mode is shown in Figure 2. Figure 8 As shown, the current is limited by the current limiting resistor 43, and the common bus voltage decreases over time. When the common bus voltage is equal to the battery stack voltage, the first switch is disconnected, the second switch is turned on, and the variable structure switch 4 enters the state as shown in FIG. Figure 6 The battery stack is directly connected to the common bus bar, and the common bus bar charges the battery stack.

[0070] Fig. 9 This is a schematic diagram of the second application of an elevator battery energy storage power supply device of the utility model. The second application example of the elevator battery energy storage power supply device is based on the first application example of the elevator battery energy storage power supply device, and a remote communication unit is added. The remote communication unit can send the real-time working condition of the elevator battery energy storage power supply device to the upper control system, or the upper control system can issue instructions to the elevator battery energy storage power supply device.

[0071] A person of ordinary skill in the art can understand that: all or part of the steps of implementing the above method embodiment can be completed by hardware related to program instructions, and the aforementioned program can be stored in a computer-readable storage medium. When the program is executed, it executes the steps of the above method embodiment; and the aforementioned storage medium includes (but is not limited to): read-only memory (ROM), random access memory (RAM), magnetic disk or optical disk, etc., various media that can store program codes.

[0072] Finally, it should be noted that the above embodiments are only used to illustrate the technical solutions of the present application, rather than to limit it. Although the present application has been described in detail with reference to the aforementioned embodiments, those skilled in the art should understand that they can still modify the technical solutions described in the aforementioned embodiments, or replace some or all of the technical features therein with equivalents. However, these modifications or replacements do not cause the essence of the corresponding technical solutions to deviate from the scope of the technical solutions of the embodiments of the present application.

Claims

1. An elevator battery energy storage power supply device, characterized in that: include: Battery charger; Elevator drive unit; Battery stack; Variable structure switch; Overcurrent protection unit; in: The elevator drive unit includes a voltage sensor, a current sensor and n frequency converters, each frequency converter drives a traction machine; the frequency converter input terminals are respectively connected to the city grid to obtain electric energy from the city grid; the frequency converter is provided with a DC bus, and the DC bus is connected in parallel with the common bus of the elevator drive unit; The charger provides charging current to the battery stack; the battery stack has a + terminal and a - terminal, and the + terminal and the - terminal of the battery stack are respectively connected to the + terminal and the - terminal of the common bus of the elevator drive unit through the variable structure switch and the overcurrent protector; The variable structure switch is controlled according to the state of the municipal power grid and the peak and valley electricity price time; The variable structure switch is controlled according to the voltage and current sensor of the elevator drive unit; The overcurrent protection unit is activated when the current of the elevator drive unit exceeds a set threshold value, and disconnects the battery stack from the common bus.

2. An elevator battery energy storage power supply device according to claim 1, characterized in that: The variable structure switch includes a first switch, a second switch, a current limiting resistor, and a circuit breaker; the circuit breaker includes third and fourth switch contacts; the first switch is connected in series with the current limiting resistor and in parallel with the second switch, and one end of the first switch is connected to the + end of the battery stack, and the other end is connected to one end of the third switch contact connected to the circuit breaker; the other end of the third switch contact of the circuit breaker is connected to the + end of the common bus of the elevator drive unit, and one end of the fourth switch contact of the circuit breaker is connected to the - end of the battery stack, and the other end is connected to the - end of the common bus of the elevator drive unit.

3. An elevator battery energy storage power supply device according to claim 1, characterized in that: The battery stack includes a battery management system and m battery modules. The battery modules are connected in series, the + end of the first battery module is the + end of the battery stack, and the - end of the last battery module is the - end of the battery stack.

4. An elevator battery energy storage power supply device according to claim 3, characterized in that: The battery module includes a battery module management system and k single cells, each of which is connected in series, the + end of the first single cell is the + end of the battery module, and the - end of the last single cell is the - end of the battery module.

5. The elevator battery energy storage power supply device according to claim 1, characterized in that: When the mains power grid is in the off-peak power supply period, the charger charges the battery stack, and the elevator drive unit is supplied with power by the mains power grid; when the mains power grid is in the peak power supply period, the charger stops charging the battery stack, and the elevator drive unit is supplied with power by the battery stack instead.

6. An elevator battery energy storage power supply device according to claim 1, characterized in that: The battery stack voltage is consistent with the common bus voltage of the elevator drive unit.

7. An elevator battery energy storage power supply device according to claim 1, characterized in that: The elevator battery energy storage and power supply device comprises a remote communication unit.

8. An elevator battery energy storage power supply device according to claim 4, characterized in that: The single cell is a solid-state lithium-ion battery and a sodium-ion battery containing polyoxymethylene, and there is no freely flowing electrolyte in the battery core.

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