Flywheel energy storage and saving system

Abstract

The invention relates to the technical field of flywheel energy storage, in particular to a flywheel energy storage and saving system which comprises a flywheel system, a power system, a capacitor system, a control system and a motor system, the power system is connected with the control system, the capacitor system and the motor system, the capacitor system is connected with the motor system, and the motor system is connected with the flywheel system. The flywheel system is connected with the control system; when the load is connected, the control system judges the size of the load. If the load is close to the maximum power of the inverter, an alternating-current power supply is connected to the flywheel system to maintain the inertia of the flywheel system, after the load is connected and the flywheel system reaches the rotating speed of normal work, the control system needs to cut off the direct power supply relation between the power supply system and the motor system, and the capacitor system is switched according to an instruction of the control system; energy is provided for a flywheel system to maintain the rotating speed, and long-time continuous keeping of flywheel kinetic energy is achieved.

Description

Technical Field

[0001] The invention relates to the technical field of flywheel energy storage, and in particular to a flywheel energy storage energy-saving system. Background Art

[0002] The flywheel energy storage and energy-saving system is mainly based on the principle of flywheel energy storage technology. It realizes the input, storage and output of electrical energy through the mutual conversion and storage between electrical energy and the mechanical kinetic energy of a high-speed rotating flywheel.

[0003] The flywheel energy storage system mainly includes the flywheel body, bearing system, electric / generator, power converter and vacuum chamber. In the energy storage stage, the external electrical energy is converted by the power converter to drive the motor to run, and the motor drives the flywheel rotor to accelerate until it reaches a certain set speed. In the process of accelerating the flywheel, the flywheel stores energy in the form of kinetic energy, completing the energy storage process of converting electrical energy into mechanical kinetic energy. In the energy release stage, the motor is used as a generator, and the high-speed rotating flywheel drives the motor to generate electricity. The power converter outputs the current and voltage suitable for the load, completing the energy release process of converting mechanical kinetic energy into electrical energy.

[0004] However, the flywheel energy storage system has a self-discharge phenomenon, that is, after stopping charging, the energy in the flywheel will be exhausted within a few to dozens of hours. This is because during the rotation of the flywheel, even without external load, it will gradually slow down due to internal friction and slight influence of the external environment, resulting in the flywheel kinetic energy not being able to be maintained for a long time. Summary of the invention

[0005] The purpose of the present invention is to provide a flywheel energy storage and energy-saving system, which solves the problem that the flywheel kinetic energy cannot be maintained for a long time in the flywheel energy storage system.

[0006] To achieve the above-mentioned object, the present invention provides a flywheel energy storage and energy-saving system, comprising a flywheel system, a power supply system, a capacitor system, a control system and a motor system;

[0007] The power supply system is connected to the control system, the capacitor system and the motor system respectively, the capacitor system is connected to the motor system, the motor system is connected to the flywheel system, and the flywheel system is connected to the control system;

[0008] The power supply system is used to supply power to the control system and the motor system, and to charge and supply power to the capacitor system;

[0009] The capacitor system is used to supply power to the motor system under the control of the control system, and to charge the motor system when there is surplus electric energy, and to store electric energy to compensate for the electric energy generated by the motor system when the system load suddenly increases;

[0010] The motor system is used to provide kinetic energy for the flywheel system, guide the flywheel to reach a normal working speed range, and output electrical energy to the outside when the flywheel is in normal working state;

[0011] The flywheel system is used to maintain the operation of the entire system;

[0012] The control system is used to detect the state of the flywheel system, control the power supply system to charge and cut off the capacitor system, control the capacitor system to supply and cut off the motor system, control the power supply system to supply and cut off the motor system, and monitor the temperature state and inverter system overload.

[0013] Wherein, the flywheel energy storage and energy-saving system further comprises a sensor component, and the sensor component is connected to the control system;

[0014] The sensor assembly is used to provide a rotation speed signal, a protection signal and a charging state signal of the capacitor system to the control system.

[0015] Wherein, the flywheel energy storage and energy-saving system further comprises a mechanical mechanism, and the mechanical mechanism is connected to the flywheel system;

[0016] The mechanical mechanism is used to physically support the entire system, and transfer part of the generated kinetic energy to the flywheel system for energy storage, and transfer part to the spring energy storage mechanism for spring energy storage, and distribute the kinetic energy sequentially to each spring energy storage mechanism through the crankshaft mechanism.

[0017] Wherein, the flywheel energy storage and energy-saving system further includes an inverter system, and the inverter system is connected to the motor system;

[0018] The inverter system is used to convert direct current into alternating current for output.

[0019] Wherein, the flywheel energy storage and energy-saving system further comprises a load system, and the load system is respectively connected to the inverter system and the control system;

[0020] The load system is used to use the electric energy provided by the motor system to work according to a predetermined function.

[0021] A flywheel energy storage and energy-saving system of the present invention, when the voltage of the capacitor system is lower than the rated voltage, the control system controls the power supply system to charge the capacitor system. The control system judges by the charging voltage signal of the capacitor system. When the maximum voltage of the capacitor system is the rated voltage specified by the capacitor, the control system controls the power supply system to cut off the power and stop charging the capacitor system. The flywheel system starts and the system switches to hot standby. After the capacitor system is fully charged, the control system connects the capacitor system to the motor system to provide it with electrical energy, and the motor system starts to rotate to provide the flywheel system with a moment of inertia from weak to strong. When the flywheel system reaches the lower limit threshold of the normal operating speed, the control system stops the capacitor system from supplying power to the motor system. At the same time, the control system controls the power supply system to charge the capacitor system. At this time, the flywheel system and the mechanical mechanism (mainly the spring mechanism) have completed the preparation of the initial kinetic energy, and the control system connects the inverter system to put the entire energy storage system in a hot standby state or a working state. When the load is connected, the control system needs to complete the judgment of the load size. If the load is lightweight, the electric energy can be directly transmitted to the load through the inverter without the need for the control system to operate. If the load is close to the maximum power of the inverter, the control system will connect the AC power supply to the flywheel system after completing the judgment to maintain the inertia of the flywheel system and prevent the reverse torque caused by the load on the motor system from causing the flywheel system to stop or get stuck. After the load is connected, when the flywheel system reaches the normal operating speed, the control system must cut off the direct power supply relationship of the power supply system to the motor system, and switch to the capacitor system to provide energy for the flywheel system to maintain the speed in accordance with the instructions of the control system, so as to achieve long-term continuous maintenance of the flywheel kinetic energy. BRIEF DESCRIPTION OF THE DRAWINGS

[0022] In order to more clearly illustrate the embodiments of the present application or the technical solutions in the prior art, the drawings required for use in the embodiments or the description of the prior art are briefly introduced below.

[0023] Figure 1 It is a principle block diagram of the flywheel energy storage and energy-saving system of the first embodiment of the present invention.

[0024] In the figure: 101 - flywheel system, 102 - power supply system, 103 - capacitor system, 104 - control system, 105 - motor system, 106 - mechanical mechanism, 107 - inverter system, 108 - load system. DETAILED DESCRIPTION

[0025] Embodiments of the present invention are described in detail below. Examples of the embodiments are shown in the accompanying drawings. The embodiments described below with reference to the accompanying drawings are exemplary and are intended to be used to explain the present invention, but should not be construed as limiting the present invention.

[0026] The first embodiment of the present application is:

[0027] See also Figure 1 ,in, Figure 1 The present invention provides a flywheel energy storage and energy saving system, which includes a flywheel system 101, a power supply system 102, a capacitor system 103, a control system 104, a motor system 105, a sensor assembly, a mechanical mechanism 106, an inverter system 107 and a load system 108.

[0028] According to this specific embodiment, the power supply system 102 is connected to the control system 104, the capacitor system 103 and the motor system 105 respectively, the capacitor system 103 is connected to the motor system 105, the motor system 105 is connected to the flywheel system 101, and the flywheel system 101 is connected to the control system 104;

[0029] The power supply system 102 is used to supply power to the control system 104 and the motor system 105, and to charge and supply power to the capacitor system 103;

[0030] The capacitor system 103 is used to supply power to the motor system 105 under the control of the control system 104, and to charge the motor system 105 when there is surplus electric energy, and to store electric energy to compensate for the electric energy generated by the motor system 105 when the system load suddenly increases;

[0031] The motor system 105 is used to provide kinetic energy to the flywheel system 101, guide the flywheel to reach a normal working speed range, and output electrical energy to the outside when the flywheel is in a normal working state;

[0032] The flywheel system 101 is used to maintain the operation of the entire system;

[0033] The control system 104 is used to detect the state of the flywheel system 101, control the power supply system 102 to charge and cut off the capacitor system 103, control the capacitor system 103 to supply and cut off the motor system 105, control the power supply system 102 to supply and cut off the motor system 105, and monitor the temperature state and overload of the inverter system 107.

[0034] The power supply system 102 is a power supply with high conversion efficiency, and the capacitor system 103 is a super capacitor, or a super capacitor group. Since the super capacitor has the ability to store and discharge electric energy, the super capacitor group is the best solution. The motor system 105 is a brushless DC motor, which can be one motor or multiple motors. The reason for selecting a brushless DC motor is that it can quickly have a very high working speed, can drive the flywheel or flywheel group to rotate, and after the control system 104 receives the speed signal, if the speed is lower than the threshold, its power supply will be turned on to maintain the design speed of the flywheel. The power supply here can be the power provided by the super capacitor or the super capacitor group, or it can be the power provided by the power supply under the action of the control system 104. The flywheel system 101 can be a single flywheel or a flywheel group composed of multiple flywheels. To maintain a certain kinetic energy, the flywheel must have enough mass to support it. The inertia is directly proportional to the mass of the flywheel system 101 and proportional to the square of the radius of the flywheel group.

[0035] Wherein, the sensor assembly is connected to the control system 104;

[0036] The sensor assembly is used to provide a rotation speed signal, a protection signal and a charging state signal of the capacitor system 103 to the control system 104 .

[0037] The sensor components mainly include a rotation speed sensor, a temperature window sensor, and a voltage and current detection circuit.

[0038] Secondly, the mechanical mechanism 106 is connected to the flywheel system 101;

[0039] The mechanical mechanism 106 is used to physically support the entire system, and transfer part of the generated kinetic energy to the flywheel system 101 for energy storage, and transfer part to the spring energy storage mechanism for spring energy storage, and distribute the kinetic energy sequentially to each spring energy storage mechanism through the crankshaft mechanism.

[0040] The mechanical mechanism 106 is a rotating shaft passing through the flywheel mass, a crankshaft attached to the rotating shaft, bearings or passive magnets (permanent magnets) for reducing friction, a spring mechanism for storing kinetic energy, and an exoskeleton structure supporting the entire system. The spring mechanism acts on the crankshaft of the flywheel shaft and stores the kinetic energy transmitted by the flywheel due to inertia by compressing and stretching the spring on the same straight line.

[0041] At the same time, the inverter system 107 is connected to the motor system 105;

[0042] The inverter system 107 is used to convert direct current into alternating current for output.

[0043] In order to achieve the conversion of DC into AC and transfer as much electric energy as possible to the load system 108, the present solution requires that the inverter system 107 has a high efficiency in converting DC into AC and consumes less power.

[0044] In addition, the load system 108 is connected to the inverter system 107 and the control system 104 respectively;

[0045] The load system 108 is used to use the electric energy provided by the motor system 105 to work according to a predetermined function.

[0046] The load system 108 is a load whose total power is smaller than the motor power.

[0047] Using a flywheel energy storage and energy saving system of this embodiment, after the power supply system 102 is powered on, it will give priority to powering the control system 104. The control system 104 detects the voltage of the capacitor system 103, the speed of the flywheel system 101, and the ambient temperature in sequence. After the detection is completed, the work is as follows:

[0048] When the voltage of the capacitor system 103 is lower than the rated voltage, the control system 104 controls the power system 102 to charge the capacitor system 103. The control system 104 makes a judgment based on the signal fed back by the sensor assembly. When the maximum voltage of the capacitor system 103 is the rated voltage specified by the capacitor, the control system 104 controls the power system 102 to cut off the power and stop charging the capacitor system 103.

[0049] After the capacitor is charged, the control system 104 connects the capacitor system 103 to the motor system 105 to provide it with electrical energy. The motor system 105 starts to rotate, providing the flywheel system 101 with a moment of inertia from weak to strong. When the flywheel system 101 reaches above the lower limit threshold of the normal operating speed, the control system 104 stops the capacitor system 103 from supplying power to the motor system 105. At the same time, the control system 104 controls the power supply system 102 to charge the capacitor system 103. At this time, the flywheel system 101 and the mechanical mechanism 106 (mainly the spring mechanism) have completed the preparation of the initial kinetic energy, and the control system 104 connects the inverter system 107 to put the entire energy storage system in a hot standby state or a working state.

[0050] When a load is connected, the control system 104 needs to make a judgment on the load size. If the load is lightweight, the electric energy can be directly transmitted to the load through the inverter without the need for the control system 104 to operate. If the load is close to the maximum power of the inverter, the control system 104 connects the AC power supply to the flywheel system 101 after making the judgment to maintain the inertia of the flywheel system 101 and prevent the motor system 105 from stopping or getting stuck due to the reverse torque caused by the load.

[0051] After the load is connected and the flywheel system 101 reaches the normal operating speed, the control system 104 must cut off the direct power supply relationship between the power supply system 102 and the motor system 105, and the capacitor system 103 will provide energy for the flywheel system 101 to maintain the speed according to the instructions of the control system 104, so as to achieve long-term continuous maintenance of the flywheel kinetic energy.

[0052] Simple and efficient, with low failure rate, it is suitable as a general solution for flywheel energy storage. It is widely used for energy saving in electric vehicle charging stations, air conditioning units, metallurgical industry ore smelting, and other high-power consumption industries.

[0053] What is disclosed above is only one or more preferred embodiments of the present application, and cannot be used to limit the scope of rights of the present application. Ordinary technicians in this field can understand that all or part of the processes of implementing the above embodiments and equivalent changes made according to the claims of the present application are still within the scope covered by the present application.

Claims

1. A flywheel energy storage and energy-saving system, comprising a flywheel system, characterized in that: It also includes power supply system, capacitor system, control system and motor system; The power supply system is connected to the control system, the capacitor system and the motor system respectively, the capacitor system is connected to the motor system, the motor system is connected to the flywheel system, and the flywheel system is connected to the control system; The power supply system is used to supply power to the control system and the motor system, and to charge and supply power to the capacitor system; The capacitor system is used to supply power to the motor system under the control of the control system, and to charge the motor system when there is surplus electric energy, and to store electric energy to compensate for the electric energy generated by the motor system when the system load suddenly increases; The motor system is used to provide kinetic energy for the flywheel system, guide the flywheel to reach a normal working speed range, and output electrical energy to the outside when the flywheel is in normal working state; The flywheel system is used to maintain the operation of the entire system; The control system is used to detect the state of the flywheel system, control the power supply system to charge and cut off the capacitor system, control the capacitor system to supply and cut off the motor system, control the power supply system to supply and cut off the motor system, and monitor the temperature state and inverter system overload.

2. The flywheel energy storage and energy saving system according to claim 1, characterized in that: The flywheel energy storage and energy saving system further comprises a sensor component, and the sensor component is connected to the control system; The sensor assembly is used to provide a rotation speed signal, a protection signal and a charging state signal of the capacitor system to the control system.

3. The flywheel energy storage and energy saving system according to claim 2, characterized in that: The flywheel energy storage and energy-saving system further comprises a mechanical mechanism, which is connected to the flywheel system; The mechanical mechanism is used to physically support the entire system, and transfer part of the generated kinetic energy to the flywheel system for energy storage, and transfer part to the spring energy storage mechanism for spring energy storage, and distribute the kinetic energy sequentially to each spring energy storage mechanism through the crankshaft mechanism.

4. The flywheel energy storage and energy saving system according to claim 3, characterized in that: The flywheel energy storage and energy saving system further comprises an inverter system, and the inverter system is connected to the motor system; The inverter system is used to convert direct current into alternating current for output.

5. The flywheel energy storage and energy saving system according to claim 4, characterized in that: The flywheel energy storage and energy-saving system further comprises a load system, which is connected to the inverter system and the control system respectively; The load system is used to use the electric energy provided by the motor system to work according to a predetermined function.

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