WO2007085346A1

WO2007085346A1 - Method for storing operational status data of an electric motor and electric motor for carrying out such a method

Info

Publication number: WO2007085346A1
Application number: PCT/EP2007/000182
Authority: WO
Inventors: Heinz-Georg Wassenhoven; Nour-Eddine Baboul; Sven Meerkamp; Dirk Brakensiek; Norbert Coenen
Original assignee: Oerlikon Textile Gmbh & Co. Kg
Priority date: 2006-01-27
Filing date: 2007-01-11
Publication date: 2007-08-02
Also published as: DE102006003890A1

Abstract

The invention relates to a method for storing operational status data of an electric motor (1), comprising a processor (4) for control thereof and a non-volatile memory (7), said non-volatile memory having a flash memory (7) embodiment which may be overwrite or sector erased and which is divided into several memory sectors (11, 12, 13, 14) for the loading of a control programme and the recording of error codes for the electric motor (1) which characterise the operational status data, at least two memory sectors (11, 12) serving for the storage of the error codes. According to the invention, the recording of operational status data of an electric motor with a contactless armature is achieved by a circular writing of the memory sectors (11, 12), wherein erasing a memory sector (11, 12) to continue the writing is first carried out after the complete writing of all memory sectors (11, 12).

Description

Description :

Method for storing operating state data of an electric motor and an electric motor for carrying out such a method

The invention relates to a method for storing operating state data of an electric motor according to the preamble of claim 1 and to an electric motor according to the preamble of claim 9.

From DE 196 39 500 Al a control device for an electromotive drive a door is known which comprises a microprocessor device and a memory device. The memory device also has a nonvolatile memory in the form of a rewritable flash ROM in addition to a volatile memory. The Flash-ROM is used to store operating parameters, necessary for the operation of the microprocessor sequence programs, as well as the deposit of customer-specific data, such as door end positions, door speed or error messages to be displayed. These data are usually only determined when the door is put into operation or entered by an operator. To store new data, the data already stored in the flash ROM is first transferred to the volatile memory. Subsequently, the content of the flash ROM is erased by the application of a voltage pulse. It is also possible to delete individual memory sectors. Subsequently, the cached content of the volatile memory together with the newly acquired or entered data is written back to one or more of the memory sectors. A disadvantage of this method proves that a continuous detection of operating state data of the electric motor, which allow the derivation of a fault history, does not occur. In addition, in the event of a failure of the operating voltage during the writing process, a complete loss of data may occur because, according to the method, the data is buffered in the volatile memory.

From EP 1 181 757 B1 a method for operating an electric motor is known, to which a microprocessor or microcontroller for executing program routines and a non-volatile memory in the form of an EEPROM or flash ROM ¹ s are associated with the storage of to be detected Operating state data when an error occurs. In this case, the operating state data are checked at intervals and optionally stored if predetermined criteria are met. In this method, the data volume to be recorded is recorded timed. This procedure has the disadvantage that a continuous gapless recording of operating state data in the event of a fault is not possible. The occurrence of a fault during the timing interval is not taken into account, so that in case of failure of the electric motor, the cause may not be determined.

The object of the present invention is to provide a method which enables the sequential acquisition of operating state data over the entire service life of the electric motor, wherein an error history can be derived from the data stored in each case, and to provide an electric motor which enables a simple and cost-effective implementation of the method allows.

This object is achieved with regard to the method by the characterizing features of claim 1. Regarding the Electric motor, the object is achieved by the characterizing features of claim 9.

Advantageous embodiments of the invention are the subject of the dependent claims.

According to claim 1 it is provided that the deletion of a memory sector for the continuation of the storage is carried out only after the complete description of all memory sectors. As a result, the stored error codes of at least one memory sector are available until the complete description of all other memory sectors, since the other memory sector is only deleted when this status is reached. Thus, at least the content of a memory sector can be read out for analysis, in the best case the content of all memory sectors is available. Due to the complete detection of the error codes, a consideration of the history of the electric motor is possible within the scope of the stored data, which allow conclusions about operating state data of the electric motor at the time of failure, the fault events of the electric motor or fault events of a driven by the electric motor component or device, the Operating state of the electric motor influence, represent. In particular when acquiring operating state data of an electric motor with contactless rotor or rotor, the data volume occurring from the current operating state representing data is very large, since the control of such electric motors compared to electric motors with conventionally mounted runners, that is, runners who are not stored non-contact, unequal is more complicated. This includes, above all, the necessary control and regulation effort to transfer the non-contact rotor to its suspended position and to keep it in operation during operation. Also, the number of influences that cause a negative impact can lead the non-contact storage is larger compared to conventionally mounted runners. The data volume to be processed would exhaust the number of maximum possible erase cycles very quickly, whereby long-term data acquisition is not guaranteed.

In addition, the method according to the invention has the advantage over the prior art that the number of erase cycles to be performed is reduced, which are necessary for the detection of the error codes, without having to restrict the acquisition of data during the detection, as in the method according to FIG EP 1 181 757 B1 is the case. If an update of the data to that in the

If the number of write and erase cycles required for updating would cause the number of write and erase cycles specified by the manufacturers to be exceeded, the number of write and erase cycles specified by the manufacturers would be exceeded. In general, the number of guaranteed write and erase cycles of flash memory is specified as approximately 10,000. The lifetime of the flash memory is thus greatly reduced by the procedure described in DE 196 39 500 A1, since the data stored in a memory sector is always erased to allow a rewriting of the memory sectors with updated data.

In particular, the deletion of a memory sector may be performed circularly in the order of its complete writing. In this way, a chronological analysis of the stored error codes is possible in case of failure of the electric motor.

Preferably, a stored in the memory sectors control routine for writing and storing the operating state data writing on at least one of the two

-A- Memory sectors accessed, temporarily outsourced to a volatile memory. In this way, it is ensured that the execution of the control routine, the limited amount of memory space of the volatile memory (RAM) is occupied only for the period of error code detection, and is otherwise available only to the control program of the electric motor.

In a preferred embodiment of the method according to the invention, the processor can be converted into a secure drive state for carrying out a writing access to the flash memory. In this drive state, the processor is released from all control tasks related to the electric motor for the period of data acquisition. This ensures that the processor at this time does not perform any other tasks within the framework of the control of the electric motor, which can prevent or at least alter the detection of the acquired operating state data. In order to avoid that the processor dwells in this state because of an error during the storage process, a time limitation of the operating data acquisition routine to be performed may be provided. After the time limit has been exceeded, the processor is automatically returned to the state in which it can perceive its control functions, regardless of the result and / or completion of the storage process.

Advantageously, a counter implemented in the flash memory can be incremented each time the processor is reset. This is to document the number of resets of the processor. The respective status of the counter is stored in the flash memory each time an error code is entered and stored. As a result, the reason for the termination of the control program can be documented, which led to a reset. Cause of the termination of the control program, for example, the Restart a higher-level control of the electric motor. In this way, it can be determined by means of incrementing the counter during the evaluation whether the time between two detected and stored error codes has been continuously recorded, that is, whether a reset of the control program has taken place between the logging of two error codes.

In addition, each time the counter is incremented, the data stored in the volatile memory may be transferred to the flash memory. This process is used for continuous data backup.

In particular, the operating hours of the electric motor can be detected in the flash memory. The operating hours counter can be realized as a real-time detection from the date of commissioning of the electric motor. This allows the assessment of occurring errors in terms of their quantity within a certain period of time. Likewise, the number of operating hours of the electric motor can be used to decide whether a repair is useful or not.

As an alternative to real-time detection, a relative time-dependent detection can be undertaken for the respective time of commissioning or recommissioning of the electric motor.

Furthermore, event times can be assigned to the acquired operating state data. Thus, starting from the initial startup or according to the alternative embodiment, the time period in which the operating state data or the corresponding one is derived can be derived from the last restart of the processor or the electric motor Error codes were detected. The event times make it possible to draw conclusions about the frequency of occurrence of a specific operating state.

According to claim 9, it is proposed that the processor is set up to control the writing and erasing of the memory sectors, such that the erasure of a memory sector for the continuation of the memory is carried out only after the complete description of all memory sectors.

In this case, the processor can in turn be integrated into the electric motor. This has the advantage that the error codes stored in the flash memory during operation of the electric motor are not lost during the removal thereof or the component driven by the electric motor together with the electric motor, but are accessible to a subsequent analysis. Preferably, the processor is arranged inside a housing enclosing the electric motor.

Furthermore, the electric motor can be connectable to an external data processing device, by means of which the at least two memory sectors serving to store the error codes can be read out. This allows for an analysis of the relevant electric motor in the installed state of the component in the device. On the other hand, the electric motor can be removed and fed separately to an analysis, without relying on the accessibility of data stored in the device. Alternatively, the read-out of the memory sectors or the query of the operating state data can be remote, for example via a local network or the Internet, to which the electric motor indirectly via a machine on which the electric motor is used, or can be connected directly. The reading or the query is done via a Communication channel which is connected directly to the control device of the electric motor drive and / or via a higher-level control unit of a workstation and / or the machine.

In particular, the electric motor may have an operating hours counter to allow a chronological analysis of the error codes occurring and to allow conclusions about the total operating time of the electric motor, which can be used as a criterion for performing any necessary repair.

The present invention will be explained in more detail with reference to a block diagram schematically illustrated in the drawing of the electric motor according to the invention.

1 shows a schematic representation of a block diagram of an electric motor 1 with a non-contact rotor, which is associated with a control device 2, which is integrated into the electric motor 1. Preferably, the arrangement is provided in the interior of a housing enclosing the electric motor 1, not shown. The control device 2 comprises a control electronics 3 and a processor 4. In the processor 4 are an analog / digital converter 5, a volatile memory 6 (RAM), a non-volatile memory in the form of a flash memory 7 and a flash interface 8, which is the communication between the volatile memory 6 (RAM) and the flash memory 7, and a communication module 9 (UART - universal asynchronous receiver and transmitter) integrated. The communication module 9 can be implemented as an independent chip of the control device 2 or as a partial function in the processor 4. The in-processor flash memory 7 is composed of a plurality of memory sectors 11, 12, 13, 14 which permanently store a control program and store error codes characterizing the operating condition data, the error events of the electric motor 1, or failure events of a component or device driven by the electric motor 1, which affect the operating state of the electric motor 1, represent serve. The number of memory sectors may also be greater than that of the described embodiment, depending on the flash memory 7 used. In this case, a division of the memory sectors 11, 12, 13, 14 serving in the deposit of the control program application sectors 13, 14 and at least two contiguous error memory sectors 11, 12. The storage of the control program or the storage of error codes serving memory sectors 11, 12, 13 14 of the flash memory 7 are only sectorally erasable, but allow a sequential description of the individual memory sectors 11, 12, 13, 14. The deletion and the description of the application sectors 13, 14 takes place only in case of need for a necessary replacement of the control program.

About the control electronics 3 generated by the processed in the processor 4 control program commands that are to change the operating state of the electric motor 1, implemented and forwarded to the electric motor 1. In the reverse direction, the operating state data that can be detected by the electric motor 1 are either forwarded directly to the control program or converted by the A / D converter 5 into corresponding signals that can be processed by the control program.

If an error event is diagnosed on the basis of the acquired operating state data by the control program, the error code uniquely characterizing this fault event is stored in one of the memory sector 11, 12 stored. For this purpose, the error code is forwarded by means of a control routine via the flash interface 8 to the memory sector 11, 12. In order to prevent an arbitrary write in one of the two memory sectors 11, 12, a logic 10 is provided, which performs the control of the write and erase operations. The logic 10 upstream of the flash memory 7 controls the data flow to be stored in the memory sectors 11, 12 and also monitors the degree of capacity utilization of the memory sectors 11, 12.

To describe the memory sectors 11, 12, the processor 4 is temporarily transferred to a safe drive state in which it can not perform any other tasks in the context of the control of the electric motor 1, which could prevent or at least alter the detection of the detected operating state data. The control routine executing the write operation is transferred from one of the memory sectors 13, 14 into the volatile memory 6 for the duration of the write operation.

Describing and deleting the memory sectors 11, 12 is circular. First, 12 error codes are stored by the logic 10 only in one of the two memory sectors 11, until its storage capacity is exhausted. Following this, the still unwritten memory sector 12 will be described. When the capacity limit of the second memory sector 12 is reached, the first memory sector 11 which has been described first is completely erased by the logic 10 in order to be described successively again following the erasure operation. Only when the memory sector 11 has been completely filled again with data in the form of error codes, the subsequent memory sector 12 is also deleted and described again. This ensures that at least the last recorded error codes can be read out when it is too an interruption of the power supply at the time of deletion or after deletion comes.

By way of example, the operating state data to be detected are explained on the basis of an electric motor 1 whose rotor is preferably magnetically mounted. The electric motor 1 can be designed as a drive of a component of a device, as described by way of example in the cited prior art. For example, the detection of the rotational speed is relevant for such an electric motor 1 in order to detect an overshoot or undershoot of the rotational speed on the basis of limit values. Likewise, the monitoring of the voltage curve during operation of the electric motor 1 and the magnetic bearing is an important criterion. Furthermore, the cases in which the rotor does not lift off the bearings or when impermissible current values occur in the coil of the magnetic bearing during acceleration, during braking or during stationary operation of the electric motor 1 are particularly relevant in the case of magnetic bearing. Further operating states to be detected can be predetermined as a function of the use of the electric motor 1 according to the invention as a drive of a component by means of corresponding component-specific criteria.

In order to visualize the data stored in the memory sectors 11, 12, they can be transmitted via the communication module 9 to an internal bus system of a device whose component to be driven by the electric motor 1 according to the invention is part of the device or to an external data processing device. For this purpose, the processor can be connected to a bus system of the external data processing device in order to transmit the data to be evaluated. Regardless of these types of data transmission and evaluation, the use of the in-processor flash memory 7 as memory enables the expansion of the electric motor 1 from the device to read this directly, without having to resort to this or having to connect a corresponding data processing device to the device.

The error codes characterizing the operating state data are assigned corresponding error event times which enable a chronological analysis of the operating states of the electric motor 1 which have occurred in the event of a fault. For this purpose, an operating hours counter is implemented in the electric motor 1, which assigns an event time in the form of a time stamp to each fault event. The operating hours counter can be realized as a real-time detection from the date of commissioning of the electric motor 1. Alternatively, a relative, on the respective time of commissioning or recommissioning of the electric motor 1 Abstellende timing be made. Thus, starting from the last restart of the processor 4 or of the electric motor 1, the period in which the operating state data or the corresponding error codes were detected can be derived.

Since situations may arise during the operation of the electric motor 1 that necessitate a reset of the control program, a counter is implemented in the flash memory 7, which is incremented at each reset. The current count is logged by the processor 4 and stored in the respective memory sector to be described 11, 12 together with the error code to be logged. In this way it can be determined during the evaluation whether a reset of the control program has taken place between two logged error codes.

Claims

Claims:

A method of storing operating state data of an electric motor (1) comprising a processor (4) serving as its controller and a nonvolatile memory (7), the nonvolatile memory being implemented as a write and sector erasable flash memory (7) is subdivided into a plurality of memory sectors (11, 12, 13, 14) for storing a control program and detecting operating mode data characterizing error codes of the electric motor (1), that at least two memory sectors (11, 12) store the data Serve error codes, wherein the memory sectors (11, 12) - are described circularly,

characterized,

in that for the purpose of detecting operating state data of an electric motor with a non-contact rotor, the erasure of a memory sector (11, 12) to continue the storage is carried out only after the complete description of all memory sectors (11, 12).

2. The method according to claim 1, characterized in that the deletion of a memory sector (11, 12) is performed circularly in the order of their complete writing.

3. The method according to any one of claims 1 or 2, characterized in that in the memory sectors (13, 14) stored control routine, the writing access to the detection and storage of the error codes on one of the at least two memory sectors (11, 12), temporarily in a volatile memory (6) is outsourced.

4. The method according to any one of claims 1 to 3, characterized in that the processor (4) for performing a write access to the flash memory (7) is converted into a secure drive status.

5. The method according to any one of claims 1 to 4, characterized in that in the flash memory (7) implemented counter is incremented at each reset of the processor (4).

6. The method according to claim 5, characterized in that at each increment of the counter in the volatile memory (6) located data in the flash memory (7) are transferred.

7. The method according to any one of claims 1 to 6, characterized in that in the flash memory (7) the operating hours of the electric motor (1) are detected.

8. The method according to any one of claims 1 to 7, characterized in that the detected operating state data event times are assigned.

9. Electric motor (1) for carrying out a method according to one of claims 1 to 8, comprising a control of the electric motor (1) serving processor (4) and in the processor (4) integrated non-volatile memory (7), wherein the non-volatile memory (7) the deposit and execution of a control program and the detection of operating state data of the electric motor (1) that serves at least two circular writable

Memory sectors (11, 12) of the non-volatile memory (7) are provided for storing error status codes characterizing the operating status data,

characterized,

the processor (4) is set up to control the writing and erasing of the memory sectors (11, 12), such that the erasure of a memory sector (11, 12) to continue the memory will take place only after the complete description of all the memory sectors (11, 12) is carried out.

10. Electric motor (1) according to claim 9, characterized in that the processor (4) in turn is integrated in the electric motor (1).

11. Electric motor (1) according to any one of claims 9 or 10, characterized in that the electric motor (1) is connectable to a data processing device, by means of which at least two of the storage of error codes serving memory sectors (11, 12) are read out.

12. Electric motor (1) according to one of claims 9 to 11, characterized in that the electric motor (1) has an operating hours counter.