Output Synchronization Compensation and Operation Switching Regulation Method and Device for an Elevator Multi-Channel Frequency Converter

Abstract

The present invention discloses an output synchronization compensation and operation switching adjustment method for multiple inverters in an elevator system, which can monitor and adjust the input and output signals of each inverter to achieve output synchronization at the edges of adaptively parallel-connected multiple inverters. The method mainly includes: an output synchronization compensation method, that is, through an output voltage and current acquisition module combined with a synchronization compensation adjustment module, parameters such as time delay, rise and fall times from the self-signal output end to the execution end at the same position in each inverter are obtained, signal differences are judged, and an optimal output compensation scheme is obtained through an algorithm to achieve output signal synchronization; an operation switching adjustment method, that is, by using the module to sample the time points when each phase is completely turned off during the phase-interchange process during the operation of the inverter, and based on this, combined with a safe switching time margin, the opening time points of the switching devices that are continuously turned on during commutation are adjusted to reduce the commutation dead time of the inverter and improve the smoothness of the output current curve of the inverter.

Description

Technical Field

[0001] The present invention relates to the technical field of elevator operation control, and in particular to an output synchronous compensation and operation switching adjustment method and device for a multi-channel elevator frequency converter. Background Art

[0002] In current ultra-high-speed elevators, multiple groups of frequency converters are often connected in parallel to ensure sufficient current load capacity. However, due to the individual differences of the switching devices of the frequency converters, it is often impossible to ensure the output edge synchronization of the parallel signals of multiple switching devices in the loop. Mostly, manual adjustment is used to adjust the output of the multi-frequency converter system. However, the adjustment is difficult, and the synchronization after adjustment is poor, resulting in circulating current in the system, increasing the heat consumption of the frequency converter, and consuming a large amount of man-hours. In addition, the dead time set by the elevator system program for the frequency converter is a fixed value with a large tolerance and cannot be adjusted independently, and the ripple of the output current curve of the frequency converter is large. Summary of the Invention

[0003] Aiming at the deficiencies of the prior art, the purpose of the present invention is to provide an output synchronous compensation and operation switching adjustment method and device for a multi-channel elevator frequency converter, which can add an adjustment module / system to realize the output synchronization of the edges of adaptively parallel-connected multi-frequency converters. At the same time, this method can also be applied to sample the output voltage of the frequency converter to obtain the dead time during commutation, and adjust the dead time of multiple groups of frequency converters in real time, and set an appropriate switching time margin, so as to improve the smoothness of the system output current curve.

[0004] The technical solution adopted by the present invention to achieve its purpose is: an output synchronous compensation and operation switching adjustment method for a multi-channel elevator frequency converter, which is used to control the input and output states of the frequency converter, and can monitor the driving signals of each phase of each power module of each frequency converter and output them to the driving end of the power module after adjustment, including the following steps:

[0005] Step S1, an output synchronous compensation method, which combines an output voltage and current acquisition module with a synchronous compensation adjustment module to obtain parameters such as the time delay, rise and fall time, etc. from the signal output end to the execution end of the corresponding phase in each frequency converter, judges the transmission differences of each signal, and obtains an optimal output compensation scheme through an algorithm to improve the consistency of the switching characteristic parameters, so as to realize the synchronization of the output signals;

[0006] Step S2: Run the switching adjustment method. Use the output voltage and current acquisition module to sample the time points when each phase is completely turned off during the phase - to - phase switching process of the frequency converter during operation. Based on this, combined with a safe switching time margin, adjust the opening time point of the switching device that is continuously turned on during commutation; according to the turn - off time of the upper bridge arm of a certain phase during commutation, adjust the opening time of the corresponding lower bridge arm of this phase, reduce the commutation dead - time of the frequency converter, and improve the smoothness of the output current curve of the frequency converter; conversely, when the lower bridge arm is turned off and then the upper bridge arm is turned on, it is the same principle.

[0007] Furthermore, the output synchronization compensation method can perform real - time system adjustment according to the parameter information of the output signals collected.

[0008] Furthermore, the operation switching adjustment method can determine the actual commutation switching time of the corresponding frequency converter through the identified commutation time and signal state of the frequency converter, and accordingly complete the phase - time adjustment of the control signal of the corresponding output frequency converter, and at the same time achieve closed - loop feedback.

[0009] Furthermore, an output synchronization compensation and operation switching adjustment method for a multi - path frequency converter of an elevator can improve the signal synchronization of a multi - frequency - converter elevator system, but does not limit the introduction position of the synchronization compensation and dead - time adjustment module involved in this method, that is, this module can be placed at the front end of the drive unit, the front end of the IGBT module, or the system - related position of a similar frequency - converter - associated unit.

[0010] Furthermore, the multi - path frequency converter is three or more groups of frequency converters.

[0011] Furthermore, an output synchronization compensation and operation switching adjustment device for a multi - path frequency converter of an elevator includes:

[0012] A synchronization compensation and dead - time adjustment module, used to synchronize and adjust the control signals of each phase of the frequency converter;

[0013] An output voltage and current signal acquisition module, used to acquire the high - speed signals of the output voltage and current of the controlled frequency converter, and can be controlled according to the number of controller units to be paralleled;

[0014] A display device, used to display the synchronization situation of the output signals of each phase when manual adjustment of the drive module constants is required at the back end.

[0015] The beneficial effects of the present invention:

[0016] The present invention can monitor and adjust the input and output signals of each frequency converter to achieve output synchronization at the edge of self - adaptive multi - frequency - converter parallel connection. The method mainly includes: an output synchronization compensation method, that is, through an output voltage and current acquisition module combined with a synchronization compensation adjustment module, parameters such as the time delay, rise and fall times from the self - signal output end to the execution end at the same position in each frequency converter are obtained, the signal differences are judged, and an optimal output compensation scheme is obtained through an algorithm to achieve output signal synchronization; an operation switching adjustment method, that is, by using the output voltage and current acquisition module to sample the time points when each phase is completely turned off during the phase - to - phase switching process during the operation of the frequency converter, and accordingly, combined with a safe switching time margin, the opening time points of the switching devices that are continuously turned on during commutation are adjusted to reduce the commutation dead - time of the frequency converter and improve the smoothness of the output current curve of the frequency converter. BRIEF DESCRIPTION OF THE DRAWINGS

[0017] Figure 1 It is a system block diagram of the output synchronization compensation and operation switching adjustment method for the elevator multi - frequency converter according to the embodiment of the present invention;

[0018] Figure 2 It is an example diagram before and after the implementation of the output synchronization compensation method;

[0019] Figure 3 It is an example diagram before and after the implementation of the operation switching adjustment method.

[0020] Description of the reference numerals:

[0021] 1 - control unit; 2 - synchronization compensation and dead - time adjustment module; 3 - drive unit; 4 - IGBT module; 5 - output voltage and current signal acquisition module; 6 - elevator traction machine. DETAILED DESCRIPTION OF THE EMBODIMENTS

[0022] The present invention will be described in detail below in conjunction with the drawings and specific embodiments. Here, the schematic embodiments and descriptions of the present invention are used to explain the present invention, but do not limit the present invention.

[0023] It should be noted that all directional indications (such as up, down, left, right, front, back, upper end, lower end, top, bottom...) in the embodiments of the present invention are only used to explain the relative position relationship and movement conditions between components in a specific posture (as shown in the drawings). If the specific posture changes, the directional indications will also change accordingly.

[0024] In the present invention, unless otherwise clearly specified or limited, the term "connection" shall be understood in a broad sense. For example, "connection" may be a fixed connection, a detachable connection, or an integral one; it may be a mechanical connection or an electrical connection; it may be directly connected or indirectly connected through an intermediate medium, and it may be the communication inside two components or the interaction relationship between two components, unless otherwise clearly limited. For those of ordinary skill in the art, the specific meaning of the above terms in the present invention can be understood according to specific circumstances.

[0025] In addition, in the present invention, descriptions such as "first", "second", etc. are only for descriptive purposes and cannot be understood as indicating or implying their relative importance or implicitly indicating the quantity of the indicated technical features. Thus, the features defined with "first" and "second" may explicitly or implicitly include at least one of such features; in addition, the technical solutions between various embodiments can be combined with each other, but it must be based on the fact that those of ordinary skill in the art can implement it. When the combination of technical solutions is contradictory or cannot be implemented, it should be considered that such a combination of technical solutions does not exist and is not within the protection scope required by the present invention.

[0026] An output synchronization compensation and operation switching adjustment method for an elevator multi-channel frequency converter, which is used to control the input and output states of the frequency converter, can monitor the driving signals of each phase of each power module of the frequency converter and adjust and output them to the driving end of the power module, and includes the following steps:

[0027] Step S1, output synchronization compensation method: By combining an output voltage and current acquisition module with a synchronization compensation adjustment module, parameters such as the time delay, rise and fall time, etc. from the signal output end to the execution end of the corresponding phase in each channel of the frequency converter are obtained, the transmission differences of each channel of signals are judged, and the optimal output compensation scheme is obtained through an algorithm to improve the consistency of the switching characteristic parameters so as to realize the synchronization of the output signals.

[0028] Step S2, operation switching adjustment method: Use the output voltage and current acquisition module to sample the time points when each phase is completely turned off during the phase-to-phase switching process during the operation of the frequency converter, and accordingly, in combination with a safe switching time margin, adjust the opening time points of the switching devices that are continuously turned on during commutation; according to the turn-off time of the upper bridge arm of a certain phase during commutation, adjust the opening time of the corresponding lower bridge arm of this phase to reduce the commutation dead time of the frequency converter and improve the smoothness of the output current curve of the frequency converter; conversely, when the lower bridge arm is turned off and then the upper bridge arm is turned on, it is the same.

[0029] Specifically, in the solution of this embodiment, the output synchronization compensation method can perform real-time system adjustment according to the parameter information of each output signal collected.

[0030] Specifically, in the solution of this embodiment, the operation switching adjustment method can determine the actual commutation switching time of the corresponding frequency converter based on the recognized commutation time and signal state of the frequency converter, and accordingly complete the phase time adjustment of the control signal output by the corresponding frequency converter, and at the same time realize closed-loop feedback.

[0031] Specifically, in the solution of this embodiment, a method for output synchronization compensation and operation switching adjustment of a multi-channel frequency converter for an elevator can improve the signal synchronization of a multi-frequency converter elevator system, but does not limit the introduction position of the synchronization compensation and dead-time adjustment module involved in this method, that is, this module can be placed at the front end of the drive unit, the front end of the IGBT module or the system-related position of a similar frequency converter-related unit.

[0032] Specifically, in the solution of this embodiment, the multi-channel frequency converter is more than three groups of frequency converters.

[0033] Specifically, in the solution of this embodiment, a device for output synchronization compensation and operation switching adjustment of a multi-channel frequency converter for an elevator includes:

[0034] A synchronization compensation and dead-time adjustment module for synchronizing and adjusting the control signals of each phase of the frequency converter;

[0035] An output voltage and current signal acquisition module for acquiring high-speed signals of the output voltage and current of the controlled frequency converter and can be controlled according to the number of controller units to be paralleled;

[0036] A display device for displaying the synchronization situation of the output signals of each phase (including the rising edge) when manual adjustment of the drive module constants is required at the back end.

[0037] Embodiment: Please refer to Figure 1 , exemplarily, the conventional control operation part in the elevator system is mainly composed of a control unit 1, a drive unit 3, an IGBT module 4, and an elevator traction machine 6. The method for output synchronization compensation and operation switching adjustment of the multi-channel frequency converter for an elevator described in this patent embodiment mainly adds a synchronization compensation and dead-time adjustment module 2 and an output voltage and current signal acquisition module 4.

[0038] In one embodiment, there are three parallel frequency converters, denoted by A, B, and C, refer to Figure 2 . The input-output delay times of the upper bridge arms of the U phase of each frequency converter are different, that is, tAup≠tBup≠tCup. Then, through the synchronization compensation method described in this patent, tAup≈tBup≈tCup can be achieved. The same applies to the upper and lower bridge arms of other phases; if the input-output signal curves of the same-position bridge arms of each frequency converter are different, this method can also be used for adjustment.

[0039] In one embodiment, there are three parallel frequency converters, denoted by A, B, and C, refer toFigure 3 After it is detected that the upper arm of phase U of frequency converter A is completely turned off, the time points for the successive turn-on of the lower arms of phase U of frequency converters A, B, and C can be adjusted to make the turn-on moments as synchronous as possible.

[0040] Compared with other existing technologies, the present invention:

[0041] The present invention can realize the monitoring and adjustment of the input and output signals of each frequency converter, and achieve the output synchronization at the edge of the parallel connection of multiple frequency converters with self-adaptability. The method mainly includes: an output synchronization compensation method, that is, by combining an output voltage and current acquisition module with a synchronization compensation adjustment module, parameters such as the time delay, rise and fall times, etc. from the self-signal output end to the execution end at the same position in each frequency converter are obtained, the signal differences are judged, and the optimal output compensation scheme is obtained through an algorithm to realize the synchronization of the output signals; an operation switching adjustment method, that is, the output voltage and current acquisition module samples the time points when each phase is completely turned off during the phase-to-phase switching process during the operation of the frequency converter, and based on this, combined with a safe switching time margin, the opening time points of the switching devices that are successively turned on during commutation are adjusted to reduce the commutation dead time of the frequency converter and improve the smoothness of the output current curve of the frequency converter.

[0042] The technical solutions provided by the embodiments of the present invention have been introduced in detail above. Specific examples are used in this article to elaborate on the principles and implementation manners of the embodiments of the present invention. The descriptions of the above embodiments are only applicable to help understand the principles of the embodiments of the present invention; at the same time, for those of ordinary skill in the art, according to the embodiments of the present invention, there will be changes in the specific implementation manners and application scopes. In summary, the content of this specification should not be construed as a limitation to the present invention.

Claims

1. A method for output synchronization compensation and operation switching regulation of an elevator multi-channel frequency converter, which is used to control the input and output states of the frequency converter, is characterized in that Monitor the drive signals of each phase of the power module of each frequency converter and output the adjusted signals to the drive end of the power module, including the following steps: Step S1: Output the synchronous compensation method. By combining the output voltage and current acquisition module with the synchronous compensation adjustment module, obtain the parameters of the time delay and rise / fall time from the signal output end to the execution end of the corresponding phase in each frequency converter, judge the transmission differences of each signal, and obtain the optimal output compensation scheme through an algorithm to improve the consistency of the switching characteristic parameters and achieve the synchronization of the output signals. Step S2: Run the switching adjustment method. Use the output voltage and current acquisition module to sample the time points when each phase is completely turned off during the phase change process in the operation of the frequency converter, and accordingly, in combination with a safe switching time margin, adjust the opening time points of the switching devices that are continuously turned on during commutation; according to the turn-off time of the upper bridge arm of a certain phase during commutation, adjust the opening time of the corresponding lower bridge arm of this phase to reduce the commutation dead time of the frequency converter and improve the smoothness of the output current curve of the frequency converter; conversely, the same applies when the lower bridge arm is turned off and then the upper bridge arm is turned on. For the output synchronous compensation method, perform real-time system adjustment according to the parameter information of each output signal collected. For the operation switching adjustment method, determine the actual commutation switching time of the corresponding frequency converter based on the identified commutation time and signal state of the frequency converter, and accordingly complete the phase time adjustment of the control signal of the corresponding output frequency converter, and at the same time achieve closed-loop feedback.

2. A method for output synchronization compensation and operation switching adjustment of a multi-channel elevator frequency converter according to claim 1, characterized in that: The multi-channel frequency converters are three or more groups of frequency converters.

3. An output synchronization compensation and operation switching adjustment device for an elevator multi-channel frequency converter that implements the method according to any one of claims 1-2, characterized in that, It includes: A synchronous compensation and dead time adjustment module for synchronizing and adjusting the control signals of each phase of the frequency converter. The synchronous compensation and dead time adjustment module is placed at the front end of the drive unit, the front end of the IGBT module or other system-related positions of the frequency converter-related units. An output voltage and current signal acquisition module for acquiring the high-speed signals of the output voltage and current of the controlled frequency converter and controlling according to the number of controllers to be paralleled. A display device for displaying the synchronization status of the output signals of each phase when manual adjustment of the drive module constants is required at the backend.

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