Flywheel test system

Abstract

The invention discloses a flywheel test system. The flywheel test system comprises a flywheel system, a power grid simulation device, a measurement device, a control device and a switch device. Wherein the flywheel system is connected with the switch device, and the switch device is connected with the power grid simulation device; the control device is used for controlling a switch in the switch device to be switched on or switched off, adjusting power grid parameters of the power grid simulation device, performing state switching among a plurality of operation states on the flywheel system, and controlling the measurement device to measure measurement parameters of measurement points; and obtaining a test result of the flywheel system according to the measurement parameters. Therefore, the flywheel system can be switched among a plurality of operation states, so that the operation state of the flywheel system is matched with the test of the flywheel system, the automatic test of the flywheel system can be realized, and the test efficiency of the flywheel system can be improved.

Description

Technical Field

[0001] The invention relates to the field of energy technology, and in particular to a flywheel testing system. Background Art

[0002] At present, flywheel energy storage technology is a kind of energy storage technology that stores energy in the form of kinetic energy. It has the advantages of fast climbing ability, high energy conversion efficiency, long service life, and easy installation. It has been widely used in the energy field. In related technologies, flywheel testing is mostly carried out manually, which has the problem of low testing efficiency. Summary of the invention

[0003] The present invention aims to solve one of the technical problems in the above-mentioned technology at least to some extent.

[0004] To this end, one object of the present invention is to propose a flywheel testing system that can switch the flywheel system among multiple operating states, so that the operating state of the flywheel system matches the test of the flywheel system, and realize automated testing of the flywheel system, which helps to improve the testing efficiency of the flywheel system.

[0005] The first aspect of the present invention proposes a flywheel testing system, comprising: a flywheel system, a power grid simulation device, a measuring device, a control device and a switching device; wherein the flywheel system is connected to the switching device, and the switching device is connected to the power grid simulation device; the control device is used to control the closing or opening of the switch in the switching device, and adjust the power grid parameters of the power grid simulation device, and switch the state of the flywheel system within multiple operating states, and control the measuring device to measure the measurement parameters of the measuring point, and obtain the test results of the flywheel system according to the measurement parameters.

[0006] The flywheel test system of the embodiment of the present invention includes a flywheel system, a power grid simulation device, a measuring device, a control device and a switch device, wherein the control device is used to control the switch in the switch device to close or open, and adjust the power grid parameters of the power grid simulation device, and switch the state of the flywheel system within multiple operating states, and control the measuring device to measure the measurement parameters of the measurement point, and obtain the test results of the flywheel system according to the measurement parameters. Thus, the state of the flywheel system can be switched within multiple operating states, so that the operating state of the flywheel system matches the test of the flywheel system, and the automatic test of the flywheel system can be realized, which helps to improve the test efficiency of the flywheel system.

[0007] In addition, the flywheel testing system proposed in the above embodiment of the present invention may also have the following additional technical features:

[0008] In one embodiment of the present invention, when the flywheel system is subjected to a grid adaptability test, the control system is also used to control the operating state of the flywheel system to switch to a discharge state; when the flywheel system is subjected to an overload test, the control system is also used to control the operating state of the flywheel system to switch to a hot standby state.

[0009] In one embodiment of the present invention, the switching device includes a first switch and a second switch, the first end of the first switch is connected to the flywheel system, the second end of the first switch is connected to the first end of the second switch, and the second end of the second switch is connected to the power grid simulation device.

[0010] In one embodiment of the present invention, when the flywheel system is subjected to a no-load test, the control device is also used to control the first switch to be opened, and the second switch to be closed; when the flywheel system is subjected to a load test, the control device is also used to control the first switch and the second switch to be closed.

[0011] In one embodiment of the present invention, the flywheel testing system further includes: a load device; the switch device further includes a third switch, the first end of the third switch is connected to the second end of the first switch, and the second end of the third switch is connected to the load device.

[0012] In one embodiment of the present invention, when an unplanned island protection test is performed on the flywheel system, the control device is also used to control the first switch, the second switch, and the third switch to close, and control the load device to operate in a charging state and / or a discharging state.

[0013] In one embodiment of the present invention, the flywheel system includes a flywheel rotor, a speed change device and a phase regulator, the flywheel rotor is transmission-connected to the speed change device, the speed change device is transmission-connected to the phase regulator, the phase regulator is connected to the power grid simulation device, and the speed of the speed change device is maintained at a set speed.

[0014] In one embodiment of the present invention, the flywheel system includes a flywheel rotor and a doubly-fed asynchronous generator, the doubly-fed asynchronous generator includes a generator stator, a generator rotor and a frequency converter, the flywheel rotor is transmission-connected to the generator rotor, the generator rotor is connected to the power grid simulation device through the frequency converter, the generator stator is connected to the power grid simulation device, and the magnetic field speed of the generator stator is maintained at a set speed.

[0015] In one embodiment of the present invention, the flywheel system includes a flywheel rotor, a speed change device and a doubly fed asynchronous generator, the doubly fed asynchronous generator includes a generator stator, a generator rotor and a frequency converter, the flywheel rotor is transmission-connected to the generator rotor through the speed change device, the generator rotor is connected to the power grid simulation device through the frequency converter, the generator stator is connected to the power grid simulation device, and the magnetic field speed of the generator stator is maintained at a set speed.

[0016] In one embodiment of the present invention, the flywheel system further comprises an electric motor, which is drivingly connected to the flywheel rotor.

[0017] Additional aspects and advantages of the present invention will be given in part in the following description and in part will be obvious from the following description, or will be learned through practice of the present invention. BRIEF DESCRIPTION OF THE DRAWINGS

[0018] The above and / or additional aspects and advantages of the present invention will become apparent and easily understood from the following description of the embodiments in conjunction with the accompanying drawings, in which:

[0019] Figure 1 A schematic diagram of the structure of a flywheel testing system according to an embodiment of the present invention;

[0020] Figure 2 is a schematic structural diagram of a flywheel testing system according to another embodiment of the present invention;

[0021] Figure 3 A schematic diagram of the structure of a flywheel system according to an embodiment of the present invention;

[0022] Figure 4 is a schematic structural diagram of a flywheel system according to another embodiment of the present invention;

[0023] Figure 5 is a schematic structural diagram of a flywheel system according to another embodiment of the present invention;

[0024] Figure 6 is a schematic structural diagram of a flywheel system according to another embodiment of the present invention;

[0025] Figure 7 is a schematic structural diagram of a flywheel system according to another embodiment of the present invention;

[0026] Figure 8 Schematic diagram of the structure of a flywheel system according to another embodiment of the present invention. DETAILED DESCRIPTION

[0027] Embodiments of the present invention are described in detail below, examples of which are shown in the accompanying drawings, wherein the same or similar reference numerals throughout represent the same or similar elements or elements having the same or similar functions. The embodiments described below with reference to the accompanying drawings are exemplary and are intended to be used to explain the present invention, and should not be construed as limiting the present invention.

[0028] The flywheel testing system according to an embodiment of the present invention is described below with reference to the accompanying drawings.

[0029] Figure 1 Schematic diagram of the structure of a flywheel testing system according to an embodiment of the present invention.

[0030] like Figure 1 As shown, the flywheel test system 100 of the embodiment of the present invention comprises a flywheel system 200, a power grid simulation device 1, a measuring device 2, a control device 3 and a switch device 4. The flywheel system 200 is connected to the switch device 4, and the switch device 4 is connected to the power grid simulation device 1.

[0031] It should be noted that the power grid simulation device 1 is not a real power grid, but a device for simulating a power grid.

[0032] It should be noted that the measuring device 2 is used to measure the measuring parameters of the measuring points, and there are no excessive restrictions on the measuring points and measuring parameters. For example, the measuring points include but are not limited to the input end, output end, grid connection point, output end of the power grid simulation device 1, etc. of the flywheel system 200, and the measuring parameters include but are not limited to voltage, current, frequency, active power, reactive power, power factor, response time, etc. The measuring device 2 includes but is not limited to voltage sensors, current sensors, power sensors, timers, etc.

[0033] It should be noted that the control device 3 can control the flywheel system 200, the power grid simulation device 1, the measuring device 2, and the switch device 4. For example, the control device 3 can be respectively connected to the flywheel system 200, the power grid simulation device 1, the measuring device 2, and the switch device 4 for data transmission, and there is no excessive limitation on the communication method. For example, the communication connection may include wireless communication, wired communication, etc.

[0034] In one embodiment, Figure 1 As shown, the control device 3 is connected to the flywheel system 200 via a communication line 61 , the control device 3 is connected to the power grid simulation device 1 via a communication line 62 , the control device 3 is connected to the measuring device 2 via a communication line 63 , and the control device 3 is connected to the switching device 4 via a communication line 64 .

[0035] The control device 3 is used to control the closing or opening of the switch in the switching device 4, adjust the grid parameters of the grid simulation device 1, switch the state of the flywheel system 200 among multiple operating states, control the measuring device 2 to measure the measurement parameters of the measuring point, and obtain the test results of the flywheel system 200 according to the measurement parameters.

[0036] It should be noted that there are not too many restrictions on grid parameters. For example, grid parameters include but are not limited to grid voltage, grid frequency, grid power factor, harmonic value on the AC side, three-phase voltage imbalance, interharmonic value, etc.

[0037] It should be noted that the flywheel system 200 may have multiple operating states, and there are no excessive restrictions on the operating states. For example, the operating states include but are not limited to a discharge state, a charge state, a hot standby state, a standby state, a shutdown state, and the like.

[0038] When the operating state of the flywheel system 200 is the discharge state, the rotation speed of the flywheel rotor in the flywheel system 200 decreases, and the flywheel rotor releases kinetic energy.

[0039] When the operating state of the flywheel system 200 is the charging state, the rotation speed of the flywheel rotor in the flywheel system 200 increases, and the flywheel rotor stores kinetic energy.

[0040] When the operating state of the flywheel system 200 is the standby state, the flywheel system 200 runs at no load, does not absorb electric energy from the power grid simulation device 1 , and does not output electric energy to the power grid simulation device 1 .

[0041] In one embodiment, the control device 3 can obtain the test mode of the flywheel system 200 based on the test category of the flywheel system 200, control the closing or opening of the switch in the switch device 4 based on the test mode, adjust the grid parameters of the grid simulation device 1 based on the test mode, and switch the flywheel system 200 between multiple operating states based on the test mode, and control the measuring device 2 to measure the measurement parameters of the measuring point based on the test mode, and obtain the test results of the flywheel system 200 according to the measurement parameters.

[0042] It is understandable that different test categories may correspond to different test methods. For example, a mapping relationship or mapping table between test categories and test methods may be established in advance. After obtaining the test category, the mapping relationship or mapping table may be queried to obtain the test method mapped to the test category as the test method of the flywheel system 200. It should be noted that there are no excessive restrictions on the mapping relationship or mapping table, and the mapping relationship or mapping table may be pre-set in the storage space of the control device 3.

[0043] It should be noted that there are no excessive restrictions on the test categories of the flywheel system 200. For example, the test categories of the flywheel system 200 include at least one of the following:

[0044] Test 1: Grid adaptability test, including but not limited to frequency adaptability test, voltage adaptability test, power quality adaptability test, etc.

[0045] Test 2: Power control test, including but not limited to active power regulation capability test, reactive power regulation capability test, power factor regulation capability test, etc. Among them, the active power regulation capability test includes active power increase capability test and active power reduction capability test, and the reactive power regulation capability test includes reactive power regulation capability test under maximum inductive reactive power condition and reactive power regulation capability test under maximum capacitive reactive power condition.

[0046] Test 3: Overload test.

[0047] Test 4: Fault ride-through test, including but not limited to low voltage ride-through test and high voltage ride-through test under no-load conditions, low voltage ride-through test and high voltage ride-through test under load conditions, etc.

[0048] Test 5: Power quality test, including but not limited to three-phase voltage unbalance test, harmonic test, DC component test, etc.

[0049] Test 6: Energy storage response test, including but not limited to charge and discharge response time test, charge and discharge adjustment time test, charge and discharge conversion time test, etc. Among them, the charge and discharge conversion time test includes charge to discharge conversion time test and discharge to charge conversion time test.

[0050] Test 7: Energy efficiency test, including but not limited to rated energy test, rated energy conversion efficiency test, etc. Among them, the rated energy test includes rated charging energy test and rated discharging energy test.

[0051] Test 8: One frequency modulation test.

[0052] Test 9: Moment of inertia test, including but not limited to the moment of inertia test under high power output conditions and the moment of inertia test under low power output conditions.

[0053] Test 10, communication test.

[0054] Test 11: Protection function test, including but not limited to network-related protection function test, unplanned island protection function test, etc.

[0055] In summary, the flywheel test system of the embodiment of the present invention includes a flywheel system, a power grid simulation device, a measuring device, a control device and a switch device, wherein the control device is used to control the switch in the switch device to close or open, and adjust the power grid parameters of the power grid simulation device, and switch the state of the flywheel system within multiple operating states, and control the measuring device to measure the measurement parameters of the measurement point, and obtain the test results of the flywheel system according to the measurement parameters. Thus, the state of the flywheel system can be switched within multiple operating states, so that the operating state of the flywheel system matches the test of the flywheel system, and the automated test of the flywheel system can be realized, which helps to improve the test efficiency of the flywheel system.

[0056] On the basis of any of the above embodiments, when the flywheel system 200 is subjected to a grid adaptability test, the control system 3 is further used to control the operating state of the flywheel system 200 to switch to a discharging state.

[0057] When the flywheel system 200 is subjected to an overload test, the control system 3 is also used to control the operating state of the flywheel system 200 to switch to a hot standby state.

[0058] It is understandable that, under other test categories of the flywheel system 200, for example, when the power factor regulation capability of the flywheel system 200 is tested, the control system 3 is also used to control the operating state of the flywheel system 200 to switch to a discharge state and / or a charge state.

[0059] Based on any of the above embodiments, Figure 2 As shown, the switch device 4 includes a first switch 41 and a second switch 42. The first end of the first switch 41 is connected to the flywheel system 200, the second end of the first switch 41 is connected to the first end of the second switch 42, and the second end of the second switch 42 is connected to the power grid simulation device 1.

[0060] It should be noted that there are no excessive limitations on the first switch 41 and the second switch 42. For example, the first switch 41 and the second switch 42 include but are not limited to MOSFET (Metal-Oxide-Semiconductor Field-Effect Transistor) and IGBT (Insulated Gate Bipolar Transistor).

[0061] In one embodiment, when the flywheel system 200 is subjected to a no-load test, the control device 3 is further configured to control the first switch 41 to be opened, and control the second switch 42 to be closed.

[0062] When the flywheel system 200 is subjected to a load test, the control device 3 is further used to control the first switch 41 and the second switch 42 to be closed.

[0063] It is understandable that under other test categories of the flywheel system 200, for example, when the flywheel system 200 is subjected to a grid adaptability test, a power control test, an overload test, or a power quality test, the control system 3 is also used to control the first switch 41 and the second switch 42 to close.

[0064] Based on any of the above embodiments, Figure 2 As shown, the flywheel test system 100 further includes a load device 5 . The switch device 4 further includes a third switch 43 , a first end of the third switch 43 is connected to a second end of the first switch 41 , and a second end of the third switch 43 is connected to the load device 5 .

[0065] It should be noted that the load device 5 is used to consume the extra active energy of the flywheel system 200 and / or the power grid simulation device 1 to balance the circuit. There is no excessive limitation on the load device 5. For example, the load device 5 may include an RLC load device, wherein the RLC load device is a device integrating resistance, inductance, and capacitance.

[0066] It should be noted that the control device 3 can control the load device 5. For example, the control device 3 can be connected to the load device 5 for communication to perform data transmission. Figure 2 As shown, the control device 3 and the load device 5 are connected via a communication line 65 .

[0067] In one embodiment, when an unplanned island protection test is performed on the flywheel system 200, the control device 3 is also used to control the first switch 41, the second switch 42, and the third switch 43 to close, and control the load device 5 to operate in a charging state and / or a discharging state.

[0068] It should be noted that there are no excessive limitations on the structure of the flywheel system 200 .

[0069] In one embodiment, Figure 3 As shown, the flywheel system 200 includes a flywheel rotor 111, a speed change device 20 and a phase regulator 30. The flywheel rotor 111 is connected to the speed change device 20, the speed change device 20 is connected to the phase regulator 30, the phase regulator 30 is connected to the power grid simulation device 1, and the speed of the speed change device 20 is maintained at a set speed.

[0070] In one embodiment, Figure 3As shown, the flywheel rotor 111 is arranged on the flywheel device 10, the flywheel rotor 111 is connected to the speed change device 20 through the transmission shaft 41, and the speed change device 20 is connected to the phase shifter 30 through the transmission shaft 42. It can be understood that the transmission shaft 41 is the input shaft of the speed change device 20, and the transmission shaft 42 is the output shaft of the speed change device 20.

[0071] In one embodiment, Figure 3 As shown, the speed change device 20 includes an input end 211 and an output end 212, the flywheel rotor 111 is connected to the input end 211 by transmission, and the output end 212 is connected to the phase regulator 30 by transmission. For example, the flywheel rotor 111 is connected to the input end 211 by a transmission shaft 41, and the output end 212 is connected to the phase regulator 30 by a transmission shaft 42.

[0072] It should be noted that no excessive limitations are imposed on the speed change device 20 and the phase regulator 30 .

[0073] In one embodiment, the transmission ratio of the transmission device 20 may be a fixed value, or the transmission ratio may be adjustable.

[0074] In one embodiment, the speed transmission device 20 includes but is not limited to a continuously variable speed transmission device, a permanent magnet speed transmission device, a hydraulic speed transmission device, a magnetorheological fluid device, a gear transmission speed transmission device, a magnetic coupling speed transmission device, a speed transmission device with adjustable speed difference, and a doubly fed asynchronous adjustable speed transmission device.

[0075] It should be noted that there are no excessive restrictions on the set speed. For example, the set speed is 3000 rpm (revolutions per minute).

[0076] In one embodiment, Figure 4 As shown, the flywheel system 200 of the embodiment of the present invention further includes an electric motor 112 , which is transmission-connected to the flywheel rotor 111 .

[0077] In one embodiment, Figure 4 As shown, the electric motor 112 is connected to the flywheel rotor 111 via a transmission shaft 41 .

[0078] In one embodiment, Figure 5 As shown, the flywheel system 200 of the embodiment of the present invention includes a flywheel rotor 111 and a doubly-fed asynchronous generator 40. The doubly-fed asynchronous generator 40 includes a generator stator, a generator rotor and a frequency converter 33. The flywheel rotor 111 is transmission-connected to the generator rotor. The generator rotor is connected to the power grid simulation device 1 through the frequency converter 33, and the generator stator is connected to the power grid simulation device 1.

[0079] In one embodiment, Figure 5 As shown, the flywheel rotor 111 is connected to the double-fed asynchronous generator 40 via a transmission shaft 41 .

[0080] It should be noted that there are no excessive restrictions on the double-fed asynchronous generator 40 and the inverter 33. For example, the inverter 33 may include a bidirectional back-to-back IGBT (Insulated Gate Bipolar Transistor) voltage source converter.

[0081] In one embodiment, Figure 6 As shown, the flywheel system 100 of the embodiment of the present invention further includes an electric motor 112 , which is transmission-connected to the flywheel rotor 111 .

[0082] In one embodiment, Figure 6 As shown, the electric motor 112 is connected to the flywheel rotor 111 via a transmission shaft 41 .

[0083] In one embodiment, Figure 7 As shown, the flywheel system 200 of the embodiment of the present invention includes a flywheel rotor 111, a speed change device 20 and a doubly fed asynchronous generator 40. The doubly fed asynchronous generator 40 includes a generator stator, a generator rotor and a frequency converter 33. The flywheel rotor 111 is transmission-connected to the generator rotor through the speed change device 20. The generator rotor is connected to the power grid simulation device 1 through the frequency converter 33. The generator stator is connected to the power grid simulation device 1.

[0084] In one embodiment, Figure 7 As shown, the flywheel rotor 111 is connected to the speed change device 20 via a transmission shaft 41, and the speed change device 20 is connected to the double-fed asynchronous generator 40 via a transmission shaft 42. It can be understood that the transmission shaft 41 is the input shaft of the speed change device 20, and the transmission shaft 42 is the output shaft of the speed change device 20.

[0085] In one embodiment, Figure 8 As shown, the flywheel system 200 of the embodiment of the present invention further includes an electric motor 112 , which is transmission-connected to the flywheel rotor 111 .

[0086] In one embodiment, Figure 8 As shown, the electric motor 112 is connected to the flywheel rotor 111 via a transmission shaft 41 .

[0087] It should be noted that Figures 3 to 8 The power grid simulation device 1 is omitted. Figures 3 to 8 The flywheel system shown is only an example of the flywheel system in the embodiment of the present invention, and is not a limitation of the flywheel system in the embodiment of the present invention.

[0088] In the description of the present invention, it should be understood that the terms "center", "longitudinal", "lateral", "length", "width", "thickness", "up", "down", "front", "back", "left", "right", "vertical", "horizontal", "top", "bottom", "inside", "outside", "clockwise", "counterclockwise", "axial", "radial", "circumferential" and the like indicate orientations or positional relationships based on the orientations or positional relationships shown in the accompanying drawings, and are only for the convenience of describing the present invention and simplifying the description, and do not indicate or imply that the referred device or element must have a specific orientation, be constructed and operated in a specific orientation, and therefore should not be understood as limiting the present invention.

[0089] In addition, the terms "first" and "second" are used for descriptive purposes only and should not be understood as indicating or implying relative importance or implicitly indicating the number of the indicated technical features. Therefore, the features defined as "first" and "second" may explicitly or implicitly include one or more of the features. In the description of the present invention, the meaning of "plurality" is two or more, unless otherwise clearly and specifically defined.

[0090] In the present invention, unless otherwise clearly specified and limited, the terms "installed", "connected", "connected", "fixed" and the like should be understood in a broad sense, for example, it can be a fixed connection, a detachable connection, or an integral connection; it can be a mechanical connection or an electrical connection; it can be a direct connection or an indirect connection through an intermediate medium, it can be the internal connection of two elements or the interaction relationship between two elements. For ordinary technicians in this field, the specific meanings of the above terms in the present invention can be understood according to specific circumstances.

[0091] In the present invention, unless otherwise clearly specified and limited, a first feature being "above" or "below" a second feature may mean that the first and second features are in direct contact, or the first and second features are in indirect contact through an intermediate medium. Moreover, a first feature being "above", "above" or "above" a second feature may mean that the first feature is directly above or obliquely above the second feature, or simply means that the first feature is higher in level than the second feature. A first feature being "below", "below" or "below" a second feature may mean that the first feature is directly below or obliquely below the second feature, or simply means that the first feature is lower in level than the second feature.

[0092] In the description of this specification, the description with reference to the terms "one embodiment", "some embodiments", "example", "specific example", or "some examples" etc. means that the specific features, structures, materials or characteristics described in conjunction with the embodiment or example are included in at least one embodiment or example of the present invention. In this specification, the schematic representations of the above terms do not necessarily refer to the same embodiment or example. Moreover, the specific features, structures, materials or characteristics described may be combined in any one or more embodiments or examples in a suitable manner. In addition, those skilled in the art may combine and combine the different embodiments or examples described in this specification and the features of the different embodiments or examples, without contradiction.

[0093] Although the embodiments of the present invention have been shown and described above, it is to be understood that the above embodiments are exemplary and are not to be construed as limitations of the present invention. A person skilled in the art may change, modify, replace and vary the above embodiments within the scope of the present invention.

Claims

1. A flywheel testing system, characterized in that: include: Flywheel system, power grid simulation device, measuring device, control device and switch device; wherein, The flywheel system is connected to the switch device, and the switch device is connected to the power grid simulation device; The control device is used to control the closing or opening of the switch in the switching device, adjust the grid parameters of the grid simulation device, switch the state of the flywheel system among multiple operating states, control the measuring device to measure the measurement parameters of the measuring point, and obtain the test results of the flywheel system based on the measurement parameters.

2. The flywheel testing system according to claim 1, characterized in that: In the case of performing a grid adaptability test on the flywheel system, the control system is further used to control the operating state of the flywheel system to switch to a discharge state; In the case of an overload test on the flywheel system, the control system is also used to control the operating state of the flywheel system to switch to a hot standby state.

3. The flywheel testing system according to claim 1, characterized in that: The switch device includes a first switch and a second switch. The first end of the first switch is connected to the flywheel system, the second end of the first switch is connected to the first end of the second switch, and the second end of the second switch is connected to the power grid simulation device.

4. The flywheel testing system according to claim 3, characterized in that: When the flywheel system is subjected to a no-load test, the control device is further used to control the first switch to be opened and the second switch to be closed; When a load test is performed on the flywheel system, the control device is further used to control the first switch and the second switch to be closed.

5. The flywheel testing system according to claim 3, characterized in that: Also includes: Load device; The switch device further includes a third switch, a first end of the third switch is connected to the second end of the first switch, and a second end of the third switch is connected to the load device.

6. The flywheel testing system according to claim 5, characterized in that: In the case of an unplanned island protection test on the flywheel system, the control device is also used to control the first switch, the second switch, and the third switch to close, and control the load device to operate in a charging state and / or a discharging state.

7. The flywheel testing system according to claim 1, characterized in that: The flywheel system includes a flywheel rotor, a speed change device and a phase regulator. The flywheel rotor is connected to the speed change device in a transmission manner. The speed change device is connected to the phase regulator in a transmission manner. The phase regulator is connected to the power grid simulation device. The speed of the speed change device is maintained at a set speed.

8. The flywheel testing system according to claim 1, characterized in that: The flywheel system includes a flywheel rotor and a doubly-fed asynchronous generator, the doubly-fed asynchronous generator includes a generator stator, a generator rotor and a frequency converter, the flywheel rotor is drivingly connected to the generator rotor, the generator rotor is connected to the power grid simulation device through the frequency converter, the generator stator is connected to the power grid simulation device, and the magnetic field speed of the generator stator is maintained at a set speed.

9. The flywheel testing system according to claim 1, characterized in that: The flywheel system includes a flywheel rotor, a speed change device and a doubly fed asynchronous generator, the doubly fed asynchronous generator includes a generator stator, a generator rotor and a frequency converter, the flywheel rotor is drivingly connected to the generator rotor through the speed change device, the generator rotor is connected to the power grid simulation device through the frequency converter, the generator stator is connected to the power grid simulation device, and the magnetic field speed of the generator stator is maintained at a set speed.

10. The flywheel testing system according to any one of claims 7 to 9, characterized in that: The flywheel system also includes an electric motor, which is drivingly connected to the flywheel rotor.

Images