Frequency converter control system, control method and device thereof and storage medium

Abstract

The invention discloses a control method and device of a frequency converter control system, the frequency converter control system, a storage medium and a computer program product, in the frequency converter control system, a switching power supply is used for controlling starting of a frequency converter and is also used for supplying power to a secondary loop; the method comprises the following steps: before the frequency converter is started, at least n secondary loops are in a power-on state; controlling the frequency converter to start; and if the frequency converter cannot be started, controlling the power supply time sequence of the n secondary circuits in the power supply state, so that the frequency converter is successfully started. According to the scheme, by controlling the power supply time sequence of the secondary loop, the switching power supply has enough power margin to control starting of the frequency converter, the frequency converter starting failure caused by insufficient instant power required by frequency converter closing is avoided, and the operation reliability of the frequency converter is improved.

Description

Technical Field

[0001] The present invention belongs to the technical field of frequency converters, and in particular relates to a control method and device for a frequency converter control system, a frequency converter control system, a storage medium and a computer program product. Background Art

[0002] The magnetic levitation variable frequency centrifugal chiller is a low-noise, low-starting current, energy-saving and efficient central air conditioner. The magnetic levitation inverter is used to drive and control the compressor and is an important core component of the entire unit. The magnetic levitation inverter is a power electronic control device that controls the AC motor by changing the motor's working power frequency. It is mainly composed of rectifier, filter, switching power supply, inverter, secondary measurement module, brake unit, drive unit, detection unit, microprocessor unit and other components. Therefore, in order to ensure the normal operation of the inverter and prevent the occurrence of some safety accidents, it is necessary to reasonably design the control and working mode of the magnetic levitation inverter control system.

[0003] The secondary load inside the inverter of the magnetic levitation variable frequency centrifugal chiller is powered by an external separately configured switching power supply. The secondary load includes the main control unit, circuit breaker, fan, contactor, etc. Before the unit starts normally, the secondary load part inside the inverter is in operation or standby state. The inverter closing operation is also powered by the switching power supply. When designing the inverter and controller, in order to consider the space volume and cost, it is often necessary to reduce the configuration of components, resulting in a reduction in the power provided by the switching power supply. The inverter startup failure may occur due to insufficient power margin provided by the switching power supply.

[0004] The above contents are only used to assist in understanding the technical solution of the present invention and do not constitute an admission that the above contents are prior art. Summary of the invention

[0005] The object of the present invention is to provide a control method, device, inverter control system, storage medium and computer program product for an inverter control system to solve the problem of inverter startup failure caused by insufficient power margin provided by a switching power supply in related schemes, so as to achieve the effect of controlling the startup of the inverter by controlling the power supply timing of the secondary circuit so that the switching power supply has sufficient power margin to control the startup of the inverter, avoiding the inverter startup failure caused by insufficient instantaneous power required for closing the inverter, and improving the operating reliability of the inverter.

[0006] The present invention provides a control method for a frequency converter control system, the frequency converter control system comprising a frequency converter, a switching power supply, and at least one secondary circuit; the switching power supply is used to control the start-up of the frequency converter and is also used to supply power to the secondary circuit; the method comprises: before the frequency converter is started, at least n of the secondary circuits are in a power-on state, n≥1; controlling the start-up of the frequency converter; judging whether the frequency converter cannot be started; if the frequency converter cannot be started, controlling the power supply timing of the n secondary circuits in the power-on state to successfully start the frequency converter.

[0007] In some embodiments, determining whether the inverter cannot start includes: after the inverter fails to start for the first time, re-controlling the inverter to start until the number of times the inverter is controlled to start reaches a preset number; if the inverter still fails to start after the number of times the inverter is controlled to start reaches a preset number, it is determined that the inverter cannot start.

[0008] In some embodiments, controlling the power supply timing of the n secondary circuits in the energized state so that the inverter starts successfully includes: controlling one of the n secondary circuits in the energized state to be powered off; controlling the inverter to start, and determining whether the inverter cannot start; if the inverter cannot start, controlling another secondary circuit in the n secondary circuits in the energized state to be powered off until the inverter starts successfully.

[0009] In some implementations, the further embodiment includes: after the frequency converter is successfully started, controlling the de-energized secondary circuit among the n secondary circuits to be powered on.

[0010] In some implementations, the method further includes: when all the n secondary circuits in the energized state are powered off, if the inverter cannot be started, a prompt message indicating that the inverter does not meet the startup conditions is issued.

[0011] Matching the above method, the present invention provides a control device of a frequency converter control system on the other hand, the frequency converter control system includes a frequency converter, a switching power supply, and at least one secondary circuit; the switching power supply is used to control the start-up of the frequency converter, and is also used to power the secondary circuit; the device includes: a control module, configured to ensure that at least n secondary circuits are in a power-on state before the frequency converter is started, n≥1; control the start-up of the frequency converter; a start detection module, configured to determine whether the frequency converter cannot be started; the control module is also configured to control the power supply timing of the n secondary circuits in the power-on state if the frequency converter cannot be started, so that the frequency converter can be successfully started.

[0012] In some embodiments, the startup detection module determines whether the inverter cannot start, including: after the inverter fails to start for the first time, re-controlling the inverter to start until the number of times the inverter is controlled to start reaches a preset number of times; if the inverter still fails to start after the number of times the inverter is controlled to start reaches a preset number of times, it is determined that the inverter cannot start.

[0013] In some embodiments, the control module controls the power supply timing of the n secondary circuits in the power-on state so that the inverter starts successfully, including: controlling one of the n secondary circuits in the power-on state to be powered off; controlling the inverter to start and determining whether the inverter cannot start; if the inverter cannot start, controlling another secondary circuit in the n secondary circuits in the power-on state to be powered off until the inverter starts successfully.

[0014] In some implementations, the control module is further configured to control the powered-off secondary circuit among the n secondary circuits to be powered on after the inverter is successfully started.

[0015] In some embodiments, the control module is further configured to issue a prompt message indicating that the inverter does not meet the startup conditions if the inverter cannot be started when all the n secondary circuits in the energized state are powered off.

[0016] Matching the above device, the present invention provides a frequency converter control system on another aspect, including: the control device of the frequency converter control system described above.

[0017] Matching the above method, the present invention provides a storage medium on another aspect, wherein the storage medium includes a stored program, wherein when the program is running, the device where the storage medium is located is controlled to execute the control method of the inverter control system described above.

[0018] Matching the above method, the present invention provides a computer program product on another aspect, wherein the computer program product includes a computer program, and when the computer program product is processed and executed, the steps of the control method of the inverter control system are implemented.

[0019] In the scheme of the present invention, in the inverter control system, the switching power supply is used to control the inverter startup and also to power the secondary circuit; before the inverter is started, at least n secondary circuits are in a powered state; at this time, the inverter is controlled to start; if the inverter cannot start, the power supply sequence of the n secondary circuits in the power supply state is controlled to successfully start the inverter. Thus, by controlling the power supply sequence of the secondary circuits, the switching power supply has sufficient power margin to control the inverter startup, avoiding the inverter startup failure caused by insufficient instantaneous power required for the inverter to close, and improving the operating reliability of the inverter.

[0020] Other features and advantages of the present invention will be set forth in the description which follows, and in part will be apparent from the description, or may be learned by practice of the present invention.

[0021] The technical solution of the present invention is further described in detail below through the accompanying drawings and embodiments. BRIEF DESCRIPTION OF THE DRAWINGS

[0022] Figure 1 A flow chart of an embodiment of a control method of a frequency converter control system of the present invention;

[0023] Figure 2 A schematic structural diagram of an embodiment of a control device of a frequency converter control system of the present invention;

[0024] Figure 3 is a system topology diagram of the frequency converter control system of the present invention;

[0025] Figure 4 A topological diagram of a switching power supply in a frequency converter control system of the present invention;

[0026] Figure 5 It is a flow chart of another embodiment of the control method of the frequency converter control system of the present invention.

[0027] In conjunction with the accompanying drawings, the reference numerals in the embodiments of the present invention are as follows:

[0028] 102-control module; 104-start detection module. DETAILED DESCRIPTION

[0029] In order to make the purpose, technical solution and advantages of the present invention clearer, the technical solution of the present invention will be clearly and completely described below in conjunction with the specific embodiments of the present invention and the corresponding drawings. Obviously, the described embodiments are only part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without making creative work are within the scope of protection of the present invention.

[0030] In order to make the power of the switching power supply meet the instantaneous power required for the inverter to close, the relevant scheme changes the configuration of the switching power supply and uses larger components to enable the switching power supply to have higher power. However, this will increase the development cost and equipment size, and cannot meet the space volume and cost requirements of the magnetic levitation frequency conversion unit.

[0031] Therefore, this scheme provides a control method for a frequency converter control system, which can successfully close the frequency converter without changing the configuration of the switching power supply, avoiding the failure of the frequency converter to start due to insufficient power margin of the switching power supply. There is no need to use larger components, which reduces the development cost of the frequency converter and makes the equipment size meet the design requirements.

[0032] According to an embodiment of the present invention, a control method of a frequency converter control system is provided, wherein the frequency converter control system comprises a frequency converter, a switching power supply, and at least one secondary circuit. The secondary circuit is a secondary load, and the switching power supply is used to control the start-up of the frequency converter and also to supply power to the secondary circuit.

[0033] The structure of the inverter control system is as follows Figure 3 As shown, the frequency converter includes a rectifier unit and an inverter unit, and a bus capacitor is arranged between the two busbars of the rectifier unit and the inverter unit. When the circuit breaker QF1 is in a closed state, the 380V three-phase AC power flows into the frequency converter after passing through the circuit breaker QF1 for rectification and inversion, and then the frequency converter transmits the processed three-phase power to the motor load in the system. The system also has multiple secondary loads, which are also powered by the 380V three-phase AC power, and the access point is located before the circuit breaker QF1. When the circuit breaker QF2 is in a closed state, the 380V three-phase AC power passes through the circuit breaker QF2 and the switching power supply and is transmitted to the secondary load. The secondary loads are arranged in parallel, and each branch where the secondary load is located is provided with relays KA1~KA4, which are used to control the power on and off of the secondary load. The system is also provided with a main control unit and a touch screen, which can display the current load status and the switching power supply status, and interact with the user, and the main control unit can control the power on and off of the secondary load.

[0034] Among them, the structure of the switching power supply is as follows Figure 4 As shown, the input side of the switching power supply is connected to two phases of the 380V three-phase AC power, and the output side is connected to the secondary load. The switching power supply includes a filter unit, a voltage conversion unit, an overcurrent and overvoltage detection unit, a protection unit, and a switch module, which can provide protection when the input three-phase power has overcurrent, overvoltage, etc., to prevent damage to the secondary load. The switching power supply also provides the required power for the inverter to close and power on. If the switching power supply provides more power to the secondary load, it may not be able to meet the power required for closing the circuit breaker QF1, resulting in failure of the inverter to start.

[0035] like Figure 1 The flow chart of an embodiment of the method of the present invention is shown in FIG. The control method of the frequency converter control system may include: steps S110 to S130.

[0036] In step S110, before the frequency converter is started, at least n secondary circuits are in a powered-on state, n≥1; and the frequency converter is controlled to start.

[0037] Before the inverter is started, the important components in the unit must be fully started before the unit can start normally. That is, before the inverter is started, some secondary circuits are already in the energized working state. The way to control the inverter startup is to control the circuit breaker QF1 to close. If the closing is successful, the inverter will start successfully.

[0038] In step S120, it is determined whether the inverter cannot be started.

[0039] When the inverter is started, the secondary circuit in the energized state consumes a certain amount of power from the switching power supply. The inverter's power margin is insufficient, which may cause the inverter to fail to start normally.

[0040] In some embodiments, in step S120, the specific process of determining whether the inverter cannot start includes: after the inverter fails to start for the first time, re-controlling the inverter to start until the number of times the inverter is controlled to start reaches a preset number of times; if the inverter still fails to start after the number of times the inverter is controlled to start reaches a preset number of times, it is determined that the inverter cannot start.

[0041] When the inverter is started, the main control unit needs to send a control command for the closing operation to the circuit breaker QF1. The closing operation is powered by the switching power supply, and the instantaneous power required for closing the circuit breaker QF1 is large. Closing only once may not necessarily succeed, so the main control unit will send multiple control commands for closing operations to the circuit breaker QF1. When the power of the switching power supply is insufficient, even if the number of closing times reaches the preset number, the circuit breaker QF1 still cannot be successfully closed. At this time, the switching power supply will send an instantaneous power overload fault to the main control unit, thinking that the inverter cannot be started.

[0042] In step S130, if the frequency converter cannot be started, the power supply sequence of the n secondary circuits in the power-on state is controlled to enable the frequency converter to be successfully started.

[0043] The power supply sequence of the secondary circuit refers to the time sequence of powering different secondary circuits, that is, controlling the power off and on of the secondary circuits in a certain sequence, so as to meet the instantaneous power required for closing the inverter and enable the inverter to start successfully.

[0044] By controlling the power supply sequence of the secondary circuit when the power margin of the switching power supply is insufficient, the power margin of the switching power supply is indirectly increased to meet the instantaneous power required by other loads (circuit breaker QF1), avoiding the failure of the inverter to start due to insufficient instantaneous power required for closing the circuit breaker, and improving the operating reliability of the inverter. At the same time, it can reduce the selection of components for the switching power supply, and components with large power supply can be omitted when designing the control system, saving development costs.

[0045] In some embodiments, in step S130, the specific process of controlling the power supply timing of the n secondary circuits in the power-on state so that the inverter can be successfully started includes: controlling one of the n secondary circuits in the power-on state to be powered off; controlling the inverter to start, and determining whether the inverter cannot start; if the inverter cannot start, controlling another secondary circuit in the n secondary circuits in the power-on state to be powered off until the inverter is successfully started.

[0046] When the inverter fails to start successfully due to insufficient power of the switching power supply, the main control unit starts to unload the secondary circuit, reducing the power required by the secondary circuit, so that the switching power supply has more power margin to successfully close the circuit breaker QF1. Specifically, Figure 3 As shown, after the main control unit determines that the inverter cannot start, it first disconnects relay KA1, load 1 stops working, and the power margin of the switching power supply is increased. At this time, the circuit breaker QF1 is closed to start the inverter. If the inverter still cannot start normally, it is considered that the power margin of the switching power supply is still insufficient. At this time, the relay KA2 is disconnected, load 2 stops working, and the power margin is further increased. At this time, the circuit breaker QF1 is closed to start the inverter. If the inverter still cannot start normally, the relays KA3 and KA4 are opened in this way, and loads 3 and 4 are stopped, so that the inverter starts successfully.

[0047] In some implementations, the further embodiment includes: after the frequency converter is successfully started, controlling the de-energized secondary circuit among the n secondary circuits to be powered on.

[0048] After disconnecting the relay of the secondary circuit, if the inverter starts successfully, the disconnected relay will be closed again after the inverter completes the startup, and the corresponding secondary load will be powered on again. Then the main control unit sends a start-up instruction to the unit, and the unit can start normally.

[0049] In some implementations, the method further includes: when all the n secondary circuits in the energized state are powered off, if the inverter cannot be started, a prompt message indicating that the inverter does not meet the startup conditions is issued.

[0050] After all secondary loads are disconnected, the power of the switching power supply is only used to control the closing of the circuit breaker QF1. If it still cannot be closed successfully, it may be that the device selection is inappropriate. At this time, the main control unit sends a fault message to the unit that the inverter has not been closed successfully and does not meet the startup conditions.

[0051] Figure 5 FIG. 1 is a flow chart of another embodiment of a control method for a frequency converter control system of the present invention. Figure 5 As shown, the method includes:

[0052] Step 1: Before the inverter is powered on, the switching power supply draws power from the input copper busbar and outputs the corresponding voltage to close the relays KA1 to KA4 of the secondary loads. At this time, loads 1 to 4 are powered on.

[0053] Step 2: The main control unit executes the start-up command of the inverter, controls the inverter to start, and determines whether the power margin of the switching power supply meets the required power of the inverter to start (the instantaneous power when the circuit breaker QF1 is closed). If the power margin of the switching power supply meets the required power of the inverter to start, the inverter can start normally, and a signal that the unit can be turned on is sent to the touch screen; if the power margin of the switching power supply does not meet the required power of the inverter to start, it is considered that the inverter cannot start normally, and step 3 is executed at this time.

[0054] Step 3, close relay KA1, the control unit controls the inverter to start again, if the inverter can start, a signal that the unit can be started is sent to the touch screen, if the inverter still cannot start, close relay KA2, the control unit controls the inverter to start again, if the inverter can start, a signal that the unit can be started is sent to the touch screen, if the inverter still cannot start, close relay KA3, the control unit controls the inverter to start again, if the inverter can start, a signal that the unit can be started is sent to the touch screen, if the inverter still cannot start, close relay KA4, the control unit controls the inverter to start again, if the inverter can start, a signal that the unit can be started is sent to the touch screen, if the inverter still cannot start, a fault message is sent that the inverter has not been successfully closed and does not have the conditions for starting.

[0055] According to the technical solution of this embodiment, in the inverter control system, the switching power supply is used to control the inverter startup and also to supply power to the secondary circuit; before the inverter is started, at least n secondary circuits are in the power-on state; at this time, the inverter is controlled to start; if the inverter cannot start, the power supply sequence of the n secondary circuits in the power supply state is controlled to successfully start the inverter. Thus, by controlling the power supply sequence of the secondary circuits, the switching power supply has sufficient power margin to control the inverter startup, avoiding the inverter startup failure due to insufficient instantaneous power required for the inverter to close the switch, and improving the operating reliability of the inverter.

[0056] According to an embodiment of the present invention, a control device for a frequency converter control system corresponding to a control method for a frequency converter control system is also provided. The frequency converter control system includes a frequency converter, a switching power supply, and at least one secondary circuit. The secondary circuit is a secondary load, and the switching power supply is used to control the start-up of the frequency converter and also to supply power to the secondary circuit.

[0057] The structure of the inverter control system is as follows Figure 3 As shown, the frequency converter includes a rectifier unit and an inverter unit, and a bus capacitor is arranged between the two busbars of the rectifier unit and the inverter unit. When the circuit breaker QF1 is in a closed state, the 380V three-phase AC power flows into the frequency converter after passing through the circuit breaker QF1 for rectification and inversion, and then the frequency converter transmits the processed three-phase power to the motor load in the system. The system also has multiple secondary loads, which are also powered by the 380V three-phase AC power, and the access point is located before the circuit breaker QF1. When the circuit breaker QF2 is in a closed state, the 380V three-phase AC power passes through the circuit breaker QF2 and the switching power supply and is transmitted to the secondary load. The secondary loads are arranged in parallel, and each branch where the secondary load is located is provided with relays KA1~KA4, which are used to control the power on and off of the secondary load. The system is also provided with a main control unit and a touch screen, which can display the current load status and the switching power supply status, and interact with the user, and the main control unit can control the power on and off of the secondary load.

[0058] Among them, the structure of the switching power supply is as follows Figure 4 As shown, the input side of the switching power supply is connected to two phases of the 380V three-phase AC power, and the output side is connected to the secondary load. The switching power supply includes a filter unit, a voltage conversion unit, an overcurrent and overvoltage detection unit, a protection unit, and a switch module, which can provide protection when the input three-phase power has overcurrent, overvoltage, etc., to prevent damage to the secondary load. The switching power supply also provides the required power for the inverter to close and power on. If the switching power supply provides more power to the secondary load, it may not be able to meet the power required for closing the circuit breaker QF1, resulting in failure of the inverter to start.

[0059] See also Figure 2 The control device of the frequency converter control system may include: a control module 102 and a start detection module 104 .

[0060] The control module 102 is configured to control the start of the frequency converter to ensure that at least n of the secondary circuits are powered on before the frequency converter is started, where n≥1; and to control the start of the frequency converter.

[0061] Before the inverter is started, the important components in the unit must be fully started before the unit can start normally. That is, before the inverter is started, some secondary circuits are already in the energized working state. The way to control the inverter startup is to control the circuit breaker QF1 to close. If the closing is successful, the inverter will start successfully.

[0062] The startup detection module 104 is configured to determine whether the inverter cannot be started.

[0063] When the inverter is started, the secondary circuit in the energized state consumes a certain amount of power from the switching power supply. The inverter's power margin is insufficient, which may cause the inverter to fail to start normally.

[0064] In some embodiments, the specific process of starting the detection module 104 to determine whether the inverter cannot start includes: after the inverter fails to start for the first time, re-controlling the inverter to start until the number of times the inverter is controlled to start reaches a preset number of times; if the inverter still fails to start after the number of times the inverter is controlled to start reaches the preset number of times, it is determined that the inverter cannot start.

[0065] When the inverter is started, the main control unit needs to send a control command for the closing operation to the circuit breaker QF1. The closing operation is powered by the switching power supply, and the instantaneous power required for closing the circuit breaker QF1 is large. Closing only once may not necessarily succeed, so the main control unit will send multiple control commands for closing operations to the circuit breaker QF1. When the power of the switching power supply is insufficient, even if the number of closing times reaches the preset number, the circuit breaker QF1 still cannot be successfully closed. At this time, the switching power supply will send an instantaneous power overload fault to the main control unit, thinking that the inverter cannot be started.

[0066] The control module 102 is further configured to control the power supply sequence of the n secondary circuits in the energized state if the frequency converter fails to start, so that the frequency converter can be successfully started.

[0067] The power supply sequence of the secondary circuit refers to the time sequence of powering different secondary circuits, that is, controlling the power off and on of the secondary circuits in a certain sequence, so as to meet the instantaneous power required for closing the inverter and enable the inverter to start successfully.

[0068] By controlling the power supply sequence of the secondary circuit when the power margin of the switching power supply is insufficient, the power margin of the switching power supply is indirectly increased to meet the instantaneous power required by other loads (circuit breaker QF1), avoiding the failure of the inverter to start due to insufficient instantaneous power required for closing the circuit breaker, and improving the operating reliability of the inverter. At the same time, it can reduce the selection of components for the switching power supply, and components with large power supply can be omitted when designing the control system, saving development costs.

[0069] In some embodiments, the control module 102 controls the power supply timing of the n secondary circuits in the power-on state to enable the specific process of the inverter to start successfully, including: among the n secondary circuits in the power-on state, controlling one of the secondary circuits to be powered off; controlling the inverter to start, and determining whether the inverter cannot start; if the inverter cannot start, then controlling another secondary circuit in the n secondary circuits in the power-on state to be powered off until the inverter starts successfully.

[0070] When the inverter fails to start successfully due to insufficient power of the switching power supply, the main control unit starts to unload the secondary circuit, reducing the power required by the secondary circuit, so that the switching power supply has more power margin to successfully close the circuit breaker QF1. Specifically, Figure 3 As shown, after the main control unit determines that the inverter cannot start, it first disconnects relay KA1, load 1 stops working, and the power margin of the switching power supply is increased. At this time, the circuit breaker QF1 is closed to start the inverter. If the inverter still cannot start normally, it is considered that the power margin of the switching power supply is still insufficient. At this time, the relay KA2 is disconnected, load 2 stops working, and the power margin is further increased. At this time, the circuit breaker QF1 is closed to start the inverter. If the inverter still cannot start normally, the relays KA3 and KA4 are opened in this way, and loads 3 and 4 are stopped, so that the inverter starts successfully.

[0071] In some implementations, the control module 102 is further configured to control the powered-off secondary circuit among the n secondary circuits to be powered on after the inverter is successfully started.

[0072] After disconnecting the relay of the secondary circuit, if the inverter starts successfully, the disconnected relay will be closed again after the inverter completes the startup, and the corresponding secondary load will be powered on again. Then the main control unit sends a start-up instruction to the unit, and the unit can start normally.

[0073] In some implementations, the control module 102 is further configured to issue a prompt message indicating that the inverter does not meet the startup conditions if the inverter cannot be started when all the n secondary circuits in the energized state are powered off.

[0074] After all secondary loads are disconnected, the power of the switching power supply is only used to control the closing of the circuit breaker QF1. If it still cannot be closed successfully, it may be that the device selection is inappropriate. At this time, the main control unit sends a fault message to the unit that the inverter has not been closed successfully and does not meet the startup conditions.

[0075] Figure 5 FIG. 1 is a flow chart of another embodiment of a control method for a frequency converter control system of the present invention. Figure 5As shown, the method includes:

[0076] Step 1: Before the inverter is powered on, the switching power supply draws power from the input copper busbar and outputs the corresponding voltage to close the relays KA1 to KA4 of the secondary loads. At this time, loads 1 to 4 are powered on.

[0077] Step 2: The main control unit executes the start-up command of the inverter, controls the inverter to start, and determines whether the power margin of the switching power supply meets the required power of the inverter to start (the instantaneous power when the circuit breaker QF1 is closed). If the power margin of the switching power supply meets the required power of the inverter to start, the inverter can start normally, and a signal that the unit can be turned on is sent to the touch screen; if the power margin of the switching power supply does not meet the required power of the inverter to start, it is considered that the inverter cannot start normally, and step 3 is executed at this time.

[0078] Step 3, close relay KA1, the control unit controls the inverter to start again, if the inverter can start, a signal that the unit can be started is sent to the touch screen, if the inverter still cannot start, close relay KA2, the control unit controls the inverter to start again, if the inverter can start, a signal that the unit can be started is sent to the touch screen, if the inverter still cannot start, close relay KA3, the control unit controls the inverter to start again, if the inverter can start, a signal that the unit can be started is sent to the touch screen, if the inverter still cannot start, close relay KA4, the control unit controls the inverter to start again, if the inverter can start, a signal that the unit can be started is sent to the touch screen, if the inverter still cannot start, a fault message is sent that the inverter has not been successfully closed and does not have the conditions for starting.

[0079] Since the processing and functions implemented by the device of this embodiment basically correspond to the embodiments, principles and examples of the aforementioned method, for the details not fully described in this embodiment, please refer to the relevant descriptions in the aforementioned embodiments, and no further elaboration will be made here.

[0080] According to the technical solution of the present invention, in the inverter control system, the switching power supply is used to control the inverter startup and also to supply power to the secondary circuit; before the inverter is started, at least n secondary circuits are in the power-on state; at this time, the inverter is controlled to start; if the inverter cannot start, the power supply sequence of the n secondary circuits in the power supply state is controlled to successfully start the inverter. Thus, by controlling the power supply sequence of the secondary circuits, the switching power supply has sufficient power margin to control the inverter startup, avoiding the inverter startup failure caused by insufficient instantaneous power required for the inverter to close, and improving the operating reliability of the inverter.

[0081] According to an embodiment of the present invention, a frequency converter control system corresponding to a control device of the frequency converter control system is also provided. The frequency converter control system may include: the control device of the frequency converter control system described above.

[0082] Since the processing and functions implemented by the inverter control system of this embodiment basically correspond to the embodiments, principles and examples of the aforementioned device, for the details not fully described in this embodiment, please refer to the relevant descriptions in the aforementioned embodiments and will not be repeated here.

[0083] According to the technical solution of the present invention, in the inverter control system, the switching power supply is used to control the inverter startup and also to supply power to the secondary circuit; before the inverter is started, at least n secondary circuits are in the power-on state; at this time, the inverter is controlled to start; if the inverter cannot start, the power supply sequence of the n secondary circuits in the power supply state is controlled to successfully start the inverter. Thus, by controlling the power supply sequence of the secondary circuits, the switching power supply has sufficient power margin to control the inverter startup, avoiding the inverter startup failure caused by insufficient instantaneous power required for the inverter to close, and improving the operating reliability of the inverter.

[0084] According to an embodiment of the present invention, a storage medium corresponding to a control method of a frequency converter control system is also provided, wherein the storage medium includes a stored program, wherein when the program is running, the device where the storage medium is located is controlled to execute the control method of the frequency converter control system described above.

[0085] Since the processing and functions implemented by the storage medium of this embodiment basically correspond to the embodiments, principles and examples of the aforementioned method, for the details not fully described in this embodiment, please refer to the relevant descriptions in the aforementioned embodiments, and no further elaboration will be made here.

[0086] According to the technical solution of the present invention, in the inverter control system, the switching power supply is used to control the inverter startup and also to supply power to the secondary circuit; before the inverter is started, at least n secondary circuits are in the power-on state; at this time, the inverter is controlled to start; if the inverter cannot start, the power supply sequence of the n secondary circuits in the power supply state is controlled to successfully start the inverter. Thus, by controlling the power supply sequence of the secondary circuits, the switching power supply has sufficient power margin to control the inverter startup, avoiding the inverter startup failure caused by insufficient instantaneous power required for the inverter to close, and improving the operating reliability of the inverter.

[0087] According to an embodiment of the present invention, a computer program product corresponding to the control method of the inverter control system is also provided. The computer program product includes a computer program. When the computer program product is processed and executed, the steps of the control method of the inverter control system are implemented.

[0088] Since the processing and functions implemented by the computer program product of this embodiment basically correspond to the embodiments, principles and examples of the aforementioned method, for the details not fully described in this embodiment, please refer to the relevant descriptions in the aforementioned embodiments and will not be repeated here.

[0089] According to the technical solution of the present invention, in the inverter control system, the switching power supply is used to control the inverter startup and also to supply power to the secondary circuit; before the inverter is started, at least n secondary circuits are in the power-on state; at this time, the inverter is controlled to start; if the inverter cannot start, the power supply sequence of the n secondary circuits in the power supply state is controlled to successfully start the inverter. Thus, by controlling the power supply sequence of the secondary circuits, the switching power supply has sufficient power margin to control the inverter startup, avoiding the inverter startup failure caused by insufficient instantaneous power required for the inverter to close, and improving the operating reliability of the inverter.

[0090] In summary, it is easy for those skilled in the art to understand that, under the premise of no conflict, the above-mentioned advantageous methods can be freely combined and superimposed.

[0091] The above description is only an embodiment of the present invention and is not intended to limit the present invention. For those skilled in the art, the present invention may have various modifications and variations. Any modification, equivalent substitution, improvement, etc. made within the spirit and principle of the present invention shall be included in the scope of the claims of the present invention.

Claims

1. A control method for a frequency converter control system, characterized in that: The inverter control system includes an inverter, a switching power supply, and at least one secondary circuit; the switching power supply is used to control the start-up of the inverter and also to supply power to the secondary circuit; The method comprises: Before the frequency converter is started, at least n of the secondary circuits are in a powered-on state, where n≥1; controlling the frequency converter to start; Determining whether the inverter cannot be started; If the frequency converter cannot be started, the power supply sequence of the n secondary circuits in the power-on state is controlled to enable the frequency converter to be successfully started.

2. The control method of the frequency converter control system according to claim 1, characterized in that: Determining whether the inverter cannot be started includes: After the inverter fails to start for the first time, re-control the inverter to start until the number of times the inverter is controlled to start reaches a preset number; If the frequency converter still fails to start after the number of times the frequency converter is controlled to start reaches a preset number, it is determined that the frequency converter cannot be started.

3. The control method of the frequency converter control system according to claim 1 or 2, characterized in that: Controlling the power supply timing of the n secondary circuits in the power-on state so that the inverter starts successfully includes: Among the n secondary circuits in a powered-on state, controlling one of the secondary circuits to be powered-off; Controlling the inverter to start, and determining whether the inverter cannot start; If the frequency converter cannot be started, then among the n secondary circuits in the energized state, another secondary circuit is controlled to be de-energized until the frequency converter is successfully started.

4. The control method of the frequency converter control system according to claim 3, characterized in that: Also includes: After the frequency converter is successfully started, the secondary circuit that is powered off among the n secondary circuits is controlled to be powered on.

5. The control method of the frequency converter control system according to claim 3, characterized in that: Also includes: In the case that the n secondary circuits in the energized state are all powered off, if the frequency converter cannot be started, a prompt message is issued indicating that the frequency converter does not meet the startup conditions.

6. A control device for a frequency converter control system, characterized in that: The inverter control system includes an inverter, a switching power supply, and at least one secondary circuit; the switching power supply is used to control the start-up of the inverter and also to supply power to the secondary circuit; The device comprises: The control module is configured to control the start of the frequency converter so that at least n of the secondary circuits are powered on before the frequency converter is started, where n≥1; and control the start of the frequency converter; A startup detection module is configured to determine whether the frequency converter cannot be started; The control module is further configured to control the power supply sequence of the n secondary circuits in the energized state if the frequency converter fails to start, so that the frequency converter can be successfully started.

7. The control device of the frequency converter control system according to claim 6, characterized in that: The startup detection module determines whether the inverter cannot be started, including: After the inverter fails to start for the first time, re-control the inverter to start until the number of times the inverter is controlled to start reaches a preset number; If the frequency converter still fails to start after the number of times the frequency converter is controlled to start reaches a preset number, it is determined that the frequency converter cannot be started.

8. A frequency converter control system, characterized in that: include: A control device for a frequency converter control system as claimed in claim 6 or 7.

9. A storage medium, characterized in that: The storage medium includes a stored program, wherein when the program is executed, the device where the storage medium is located is controlled to execute the control method of the frequency converter control system according to any one of claims 1 to 5.

10. A computer program product, comprising a computer program, characterized in that When the computer program is executed by a processor, the steps of the method according to any one of claims 1 to 5 are implemented.

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