JPH06261593A - Motor control device - Google Patents

Abstract

PURPOSE:To automatically set data when a control board is replaced by a method wherein data in a nonvolatile memory inside the control board is compared with data in an external memory and, when there exists a difference, the data in the nonvolatile memory is replaced by the data in the external memory. CONSTITUTION:When a control power supply 7 is turned on, data in a nonvolatile memory 42 inside a control board is compared with data in an external memory 8. When there exists a difference, the data in the external memory 8 is transferred to the control board 4 and it is replaced by the data in the nonvolatile memory 42. When the control power supply 7 is turned off, the present time of a clock 44 is recorded in the nonvolatile memory 42. The service-interruption time is judged from the time when a service interruption is restored. When the service-interruption time is a prescribed time or higher, the same processing is performed. When the service-interruption time is within the prescribed time, an operation is restarted immediately by using the data in the nonvolatile memory 42 inside the control board 4 under a condition that an operating signal is input. Thereby, when the control board is replaced, the data can be set automatically.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention comprises a power conversion circuit for converting electric power into electric power of arbitrary voltage and frequency to control the electric motor at a variable speed, and a control circuit for controlling the electric power conversion circuit. Related to the electric motor control unit that digitized the control, it is possible to restart the control circuit immediately after the momentary power failure by distinguishing between normal control power on / off and momentary power failure without backing up the control power source. The present invention relates to an electric motor control device capable of automatically identifying the exchange of substrates when copying, and transferring the set constant without human intervention.

[0002]

2. Description of the Related Art In recent motor control devices, digitalization of control has progressed and performance has been improved, but problems specific to digital control devices have also arisen.

That is, the first problem is that the control power supply required for the control circuit is more important, and the cost of the control power supply in the device is higher, and the second is the momentary power failure. On the other hand, high-speed digital control is extremely weak and it is necessary to back up the control power supply so that the motor control device does not go down. Third, if the above backup is not done, recovery from an instantaneous power failure This is because the subsequent digital control circuit is reset and requires a long period of initialization (initialization) before the normal operation can be performed again, during which the rotation speed of the electric motor is greatly reduced.

Further, although adjustment like an analog control device is no longer required, it is generally necessary to set data for digital control in a memory, and when the control board is replaced, it is troublesome to reload it. One of the problems is that it is costly and burdens the user. Hereinafter, these problems will be described with reference to specific examples.

FIG. 3 is a block diagram showing a configuration example of a conventional electric motor control device of this type. In FIG. 3, 1 is an AC power source, 2 is a motor to be controlled, 3 is a semiconductor, a capacitor, a reactor, etc.
A power conversion circuit for converting the electric power of a frequency into variable speed control of the electric motor, 4 a control board for controlling the electric power conversion circuit 3, 5 an electric motor rotation sensor for detecting the rotational speed of the electric motor 2, and 6 an electric motor 2 Is a sensor for detecting the current voltage and the like, and 7 is a control power supply for supplying power to the control board 4.

In the control circuit 4, 41 is a control CPU, 42 is a non-volatile memory for recording control programs and setting constants, 43 is RAM for temporarily storing control variables, and 44 is a clock. , 45 is a battery for backing up the clock 44, 46 is a power control circuit for directly controlling the power conversion circuit 3, 47 is a sensor interface for detecting the voltage and current of the electric motor 2 and the power conversion circuit 3, and 48 is a human being as described above. It is a man-machine interface that writes and modifies configuration constants, and these are common components.

As the non-volatile memory 42, a battery-backed CMOS static RA is used.
M, EEPROM, mask ROM, etc. are common. In addition, the power control circuit 46, the sensor interface 4
7. The man-machine interface 48 constitutes an input / output device.

In such an electric motor control device, even if a short-time power failure (instantaneous power failure) occurs, if the device is not stopped and the operation is to be continued, the control power supply 7 is in the power failure period. It is common to back up. It is unrealistic to back up to the AC power supply 1, and it is common to make the control power supply 7 an uninterruptible power supply by a battery or, as shown in FIG. However, either method will increase the cost of the control power supply 7.

On the other hand, if the control power supply 7 is not backed up, the CPU 41 stops almost at the same time as the occurrence of the power failure, and it becomes necessary to initialize the entire control board 4 after the power is restored. Generally, it takes a considerable time (0.1 seconds to several seconds) to initialize the digital control circuit, and the motor control device cannot be controlled for a period longer than the power failure period (power failure period + initialization time). Becomes Therefore, there is an inconvenience that the rotation speed of the electric motor 2 is reduced more than necessary. Furthermore, when the power supply is turned on without backing up the control power supply 7, it is technically difficult to identify whether the power supply is on by normal operation or after power off due to a power failure.

Also, the control board 4 may be damaged for some reason.
When replacing the above, it is necessary to prepare a spare board to which the set constants are input for all control devices, or to copy the above set constants to the spare board. It is necessary to input the data by using the man-machine interface 48 or auxiliaryly input the data by using a personal computer or a memory card. Whichever method is used, when the control board 4 is replaced, it is difficult for the board itself to identify it, and a human needs to perform some operation, which takes time and effort.

[0011]

As described above, in the motor control device adopting the digital control, if the control power supply is backed up against an instantaneous power failure, the cost of the control power supply increases, and the control If the power supply is not backed up, the control circuit cannot be restarted immediately when the power is restored, and the problem that the number of rotations of the motor decreases more than necessary, and the problem that normal control power on / off and instantaneous power failure cannot be distinguished, Furthermore, when the control board is replaced for some reason such as a failure, it is necessary for a person to perform some operation in order to input data, which takes time and labor.

An object of the present invention is to distinguish between normal control power on / off and momentary power failure without backing up the control power source, to restart the control circuit immediately after the momentary power failure, and to replace the control board when replacing the board. An object of the present invention is to provide an extremely reliable electric motor control device capable of automatically identifying exchanges and transferring the set constants without human intervention.

[0013]

In order to achieve the above object, an electric power conversion circuit for converting electric power into electric power of an arbitrary voltage and frequency to control an electric motor at a variable speed, and a control for controlling the electric power conversion circuit. In a motor control device composed of a circuit,

First, in the invention described in claim 1, a control CPU, a non-volatile memory in which data such as setting constants are recorded, a RAM in which control variables are temporarily recorded,
A clock and other input / output devices, at least one control board connected to the CPU, and a non-volatile memory that can be disconnected / connected independently of the control board.
From an external memory that records data such as setting constants,
The above control circuit is configured, and when the control power supply for supplying power to the control circuit is turned on, it is determined whether or not there is a difference between the data in the non-volatile memory in the control board and the data in the external memory, If there is a difference, a means for transferring the data in the external memory into the control board and replacing the data in the non-volatile memory in the control board is provided.

Further, in the invention described in claim 2, a control CPU, a non-volatile memory in which data such as setting constants are recorded, a RAM in which control variables are temporarily recorded,
A clock and other input / output devices, at least one control board connected to the CPU, and a non-volatile memory that can be disconnected / connected independently of the control board.
From an external memory that records data such as setting constants,
When the control power supply that configures the control circuit and supplies power to the control circuit is turned off, the current time of the clock in the control board is recorded in the non-volatile memory, and the power failure time starts from the time when the control power supply is turned on next time. If, as a result, the power failure time is longer than the predetermined time, when the control power is turned on, the data in the nonvolatile memory in the control board and the data in the external memory are compared to see if there is a difference between them. If there is a difference, transfer the data in the external memory to the control board and replace it with the data in the non-volatile memory in the control board.If the power failure time is within the predetermined time, A means for immediately restarting the operation is provided on condition that the operation signal is input by using the data in the nonvolatile memory.

[0016]

Therefore, in the motor controller of the present invention,
Data such as setting constants are input in advance to an external memory provided independently of the control board.

When the control power supply is turned on, the data in the nonvolatile memory in the control board is compared with the data in the external memory,
It is determined whether or not there is a difference between the two, and if there is a difference, it is identified that the control board has been replaced, and the data in the non-volatile memory in the control board is replaced with the data in the external memory. As a result, when replacing the control board,
Substrate replacement can be automatically identified and the set constant can be transferred without human intervention.

Also, when the control power supply is turned on, the power failure time is confirmed by a clock, and if it is judged that there is an instantaneous power failure, data such as setting constants are not compared, and the initialization operation is minimized. , Is immediately restarted.

Thus, it is possible to distinguish between the normal control power on / off and the momentary power failure and to restart the control circuit immediately after the momentary power failure without backing up the control power source.

[0020]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS An embodiment of the present invention will be described in detail below with reference to the drawings.

FIG. 1 is a block diagram showing a configuration example of an electric motor control device according to the present invention. The same parts as those in FIG. 3 are designated by the same reference numerals, and the description thereof will be omitted. Only different parts will be described here. That is, in FIG. 1, the control power supply 7 is the same as that described in FIG. 3, but no backup or the like is necessary.

Further, an external memory 8 which can be arbitrarily connected and disconnected is provided independently of the control board 4. It is necessary to use a non-volatile memory 81 as the external memory 8. This non-volatile memory 81, like the non-volatile memory 42 in the control board 4, is a battery-backed CMOS static RAM, EEPROM,
A mask ROM or the like is common. Further, in the non-volatile memory 42 in the control board 4, the following control programs are recorded in addition to the control programs described above.

That is, when the control power supply 7 is turned on, the data in the non-volatile memory 42 in the control board 4 and the data in the external memory 8 are compared to determine whether there is a difference between them.
If there is a difference, the data in the external memory 8 is transferred to the control board 4
The control program which is transferred to the inside and is replaced with the data in the non-volatile memory 42 in the control board 4, and the current time of the clock 44 in the control board 4 is recorded in the non-volatile memory 42 when the control power supply 7 is turned off. When the control power supply 7 is turned on, the power outage time is determined from the time when the control power supply 7 is turned on.
The data in the non-volatile memory 42 inside is compared with the data in the external memory 8 to determine whether there is a difference between them, and if there is a difference, the data in the external memory 8 is transferred to the control board 4. The data is replaced with the data in the nonvolatile memory 42 in the control board 4, and when the power failure time is within a predetermined time, the operation is immediately restarted using the data in the nonvolatile memory 42 in the control board 4 as a condition for inputting the operation signal. It is recorded as a control program that does. Next, the operation of the electric motor control device of the present embodiment configured as described above will be described.

The setting constants are previously input to the external memory 8. That is, in general, the setting constant is
Information for distinguishing the electric motor 2 and the power conversion circuit 3 from other electric motors and the power conversion circuit is included. Specifically, the rated capacity (KW) of the electric motor 2, the rated current and the rated capacity of the power conversion circuit, the control gain that determines the control response of the current and the rotational speed, and the like. The data in the external memory 8 always corresponds to 1: 1 with the power conversion circuit 3, and if there are a plurality of motor control devices, prepare the same number of external memories 8.

When the control board 4 is replaced, the external memory 8 is not replaced and is attached to a new control board 4, and then the control power supply 7 is turned on. Then, the new control board 4
In the CPU 41, when the control power supply 7 is turned on, first, the setting constants recorded in the nonvolatile memory 42 in the control board 4 and
The set constant recorded in the nonvolatile memory 81 in the external memory 8 is compared. As a result, if there is a difference between the two, it is identified that the control board 4 has been replaced, and the setting constant of the non-volatile memory 42 in the control board 4 is corrected with the setting constant on the external memory 8 side being positive. It This operation is automatically performed when the control power supply 7 is turned on, without human intervention.

On the other hand, the problem here is to distinguish between the normal control power supply 7 being turned on and the control power supply 7 being turned on with the restoration of power after the momentary power failure. Usually, when an instantaneous power failure occurs,
The electric motor control device is required to restart the operation immediately after the power is restored. If the restart of the operation is delayed due to the data comparison with the external memory 8 as described above, the electric motor 2
The number of rotations of will decrease, which may cause a problem. Therefore, the time period during which the control power supply 7 is off, that is, the power failure time is measured by the clock 44.

That is, when the control power supply 7 is turned off,
The current time is immediately recorded in the nonvolatile memory 42, and the power failure time is determined from the time when the control power supply 7 is turned on next time. Generally, the momentary power failure is about 10ms to 1s,
Within this time, the minimum necessary initialization operation is performed to restart the operation immediately. Specifically, it includes resetting the power control circuit 46 and the sensor interface 47 in the control board 4. Since the control board 4 cannot be replaced in such a short time,
Data comparison with the external memory 8 described above is not performed.

FIG. 2 is a flow chart showing the operation contents. That is, as shown in FIG. 2, immediately after the control power supply 7 is turned on, the current time is checked to determine whether the power failure time is within a predetermined time. This predetermined time is generally the maximum value of the time determined to be the momentary power failure time.

As a result, if the power failure time is within a predetermined time, it is determined that an instantaneous power failure has occurred, the control board 4 is initialized as described above so that it can operate normally, and the operation signal is input. The control circuit is immediately started and the operation is restarted on the condition that the operation is performed.

If the power failure time exceeds a predetermined time, it is judged that the normal control power supply 7 is turned on, and the setting constant of the external memory 8 and the nonvolatile memory 42 in the control board 4 are determined.
The setting constant of is compared. As a result of this comparison, if there is a difference between the two data, it is determined that the control board 4 has been replaced, and it is first checked whether the correct control board 4 is mounted, and then the setting constant of the external memory 8 is set to the control board. After being transferred to the non-volatile memory 42 in the control circuit 4, the control board 4 is initialized. Here, in general, the initialization operation is
Both the hardware and the software are included, and particularly, the initialization of the hardware is such that the setting is performed only once according to the power conversion circuit 3 (for example, the gain of the current detection sensor 6 is set to the power conversion circuit). The initialization operation of adjusting according to the rated current of 3) is included. If there is no difference between the two data, it is determined that the normal control power supply 7 without the replacement of the control board 4 is turned on, and the normal initialization operation of the control board 4 is performed.

As described above, in this embodiment, the electric power is converted into electric power of arbitrary voltage and frequency to control the electric motor 2 at a variable speed, and the control circuit for controlling the electric power conversion circuit 3. In the electric motor control device composed of, a control CPU 41, a non-volatile memory 42 for recording data such as setting constants, a RAM 43 for temporarily recording control variables, a clock 44, a battery 45, and other input devices. At least one control board 4 including output devices 46, 47, 48 connected to the CPU 41, and a non-volatile memory 81 that can be arbitrarily disconnected / connected independently of the control board 4.
The external memory 8 for storing data such as setting constants constitutes the above control circuit, and when the control power supply 7 for supplying electric power to the control circuit is turned on, the data in the non-volatile memory 42 in the control board 4 is turned on. And the data in the external memory 8 are compared to determine whether or not there is a difference between them, and if there is a difference, the data in the external memory 8 is transferred to the control board 4 and the nonvolatile memory in the control board 4 is transferred. 42, and when the control power supply 7 is turned off, the current time of the clock in the control board 4 is recorded in the non-volatile memory 42, and then the control power supply 7
The power failure time is determined from the time when the power is turned on, and if the power failure time is more than the predetermined time as a result, when the control power supply 7 is turned on, the data in the nonvolatile memory 42 in the control board 4 and the data in the external memory 8 are turned on. Is compared to determine whether or not there is a difference between them, and if there is a difference, the data in the external memory 8 is transferred to the control board 4 and replaced with the data in the non-volatile memory 42 in the control board 4. When the power failure time is within a predetermined time, the data is stored in the non-volatile memory 42 in the control board 4 and the operation is immediately restarted on condition that the operation signal is input.

Therefore, data such as setting constants are input in advance to the external memory 8 provided independently of the control board 4, and when the control power supply 7 is turned on, the data of the nonvolatile memory 42 in the control board 4 is stored. The data in the external memory 8 is compared to determine whether there is a difference between the two. If there is a difference, it is identified that the control board 4 has been replaced, and the nonvolatile memory in the control board 4 is identified. The data in 42 is replaced with the data in the external memory 8. Thus, when the control board 4 is replaced, it is possible to automatically identify the replacement of the board and transfer the set constant without human intervention.

Also, when the control power supply 7 is turned on, the power outage time is confirmed by the clock 44, and if it is determined that there is an instantaneous power outage, data such as setting constants are not compared, and the initialization operation is minimized. And it is restarted immediately.

This makes it possible to distinguish between normal control power on / off and momentary power failure and to restart the control circuit immediately after the momentary power failure without backing up the control power source 7. The present invention is not limited to the above embodiment, but can be implemented in the same manner as described below.

(A) In the above embodiment, the case where two control programs are recorded in addition to the original control program in the non-volatile memory 42 in the control board 4 has been described. Of these two control programs, Either one of the control programs may be recorded.

(B) In the above embodiment, the case where the clock 44 in the control board 4 is backed up by the battery 45 has been described. However, the clock 44 does not always have to keep time, and after the control power is cut off by a capacitor or the like. If the time can be measured for several seconds or more, the present invention can be similarly applied.

[0037]

As described above, according to the present invention, a non-volatile memory which can be arbitrarily disconnected / connected independently of the control board is provided, and an external memory for recording data such as setting constants is provided. When the control power supply that supplies power to the control circuit is turned on, the data in the non-volatile memory in the control board is compared with the data in the external memory to determine whether there is a difference between them, and if there is a difference, A means for transferring the data in the external memory into the control board to replace the data in the non-volatile memory in the control board is provided, and when the control power supply for supplying power to the control circuit is turned off, the current time of the clock in the control board is set. It is recorded in the non-volatile memory, and the power failure time is judged from the time when the control power supply is turned on next time. As a result, if the power failure time is more than a predetermined time, the nonvolatile power in the control board is stored when the control power supply is turned on. Note And the data in the external memory are compared to determine whether there is a difference between them, and if there is a difference, the data in the external memory is transferred to the control board and stored in the non-volatile memory in the control board. When the power failure time is within a predetermined time by replacing with the data, it is equipped with a means to restart the operation immediately by using the data of the non-volatile memory in the control board on condition of the input of the operation signal. The normal control power on / off and the momentary power failure can be identified without restarting, and the control circuit can be restarted immediately after the momentary power failure.When the control board is replaced, the board replacement is automatically identified and the setting constant is set by the human. It is possible to provide an extremely reliable electric motor control device that can be copied without using hands.

[Brief description of drawings]

FIG. 1 is a block diagram showing an embodiment of an electric motor control device according to the present invention.

FIG. 2 is a flowchart for explaining the operation in the same embodiment.

FIG. 3 is a block diagram showing a configuration example of a conventional electric motor control device.

[Explanation of symbols]

DESCRIPTION OF SYMBOLS 1 ... AC power supply, 2 ... Electric motor, 3 ... Power conversion circuit, 4 ... Control board, 41 ... CPU, 42 ... Non-volatile memory, 43 ... R
AM, 44 ... Clock, 45 ... Battery, 46 ... Power control circuit, 47 ... Sensor interface, 48 ... Man-machine interface, 5 ... Motor rotation sensor, 6 ... Sensor, 7 ... Control power supply, 8 ... External memory, 81 ... Nonvolatile memory.

Claims (2)

[Claims] 1. A motor control device comprising a power conversion circuit for converting electric power into electric power of an arbitrary voltage and frequency to control the electric motor at a variable speed, and a control circuit for controlling the power conversion circuit. CPU, non-volatile memory for recording data such as setting constants, RA for temporarily recording control variables
M, a clock, and other input / output devices, at least one control board connected to the CPU, and a non-volatile memory that can be arbitrarily disconnected / connected independently of the control board. The control circuit is configured from an external memory that records data, and when the control power supply that supplies power to the control circuit is turned on, the data in the nonvolatile memory in the control board and the data in the external memory are compared. Then, it is determined whether or not there is a difference between the two, and if there is a difference, means for transferring the data in the external memory into the control board and replacing the data in the non-volatile memory in the control board is provided. An electric motor control device characterized by comprising: 2. A motor control device comprising a power conversion circuit for converting electric power into electric power of an arbitrary voltage and frequency to control the electric motor at a variable speed, and a control circuit for controlling the power conversion circuit, wherein: CPU, non-volatile memory for recording data such as setting constants, RA for temporarily recording control variables
M, a clock, and other input / output devices, at least one control board connected to the CPU, and a non-volatile memory that can be arbitrarily disconnected / connected independently of the control board. The control circuit is configured from an external memory that records data, and when the control power supply that supplies power to the control circuit is turned off, the current time of the clock in the control board is recorded in the nonvolatile memory. Then, the power failure time is determined from the time when the control power supply is turned on, and if the power failure time is equal to or longer than a predetermined time as a result, when the control power supply is turned on, the data of the nonvolatile memory in the control board is stored. The data in the external memory is compared to determine whether or not there is a difference, and if there is a difference, the data in the external memory is transferred to the control board and the nonvolatile memory in the control board is transferred. When the power failure time is within a predetermined time, the device further comprises means for immediately restarting the operation on the condition that the operation signal is input using the data of the nonvolatile memory in the control board. A characteristic motor control device.