JPS5939771B2 - Digital control device for analog signal processing - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention is suitable for use in the field of power electronics, which uses semiconductor electronic elements or devices such as thyristors to control power, switch on and off, etc. using digital control devices that process analog input signals. The present invention relates to a digital control device for analog signal processing.

FIG. 1 is a block diagram showing a conventional example of this type of control device.

That is, an arithmetic processing unit (hereinafter also referred to as a CPU card) integrated on a single printed circuit board or card.

) 1 and various input/output devices (hereinafter also referred to as input or output cards) 2 to 5 are connected in parallel to each other via a bus line 6. The input/output device is, for example, a digital input card (DI card) 2 that reads digital information such as ON/OFF of a relay contact, and drives a relay etc. using digital output information such as ON/OFF outputted from a CPU card. Digital output card (DO card)
3. Analog input card (AI card) 5 and CPU card 1 that convert analog input signals to digital signals
It is composed of an analog output card (AO card) 4, etc., which converts digital output information from the AO card into an analog signal and outputs the analog signal. When using such a digital control device to process analog signals used in the power electronics field, the signal level, analog
Issues include digital conversion and insulation for noise removal. Therefore, especially regarding the signal level, the level should be determined and handled, for example, o±IOV, or signal conditioning (SIGNAL CONDITIONING) should be used for signals exceeding the above range.
Normally, a separate means is provided to import the information.

However, if signal adjustment means were provided each time to deal with various analog input signals, the device would not only become large-scale but also have poor cohesiveness as a whole.
Moreover, it has the disadvantage of being expensive. The present invention has been made in view of the above, and it is an object of the present invention to provide a compact and inexpensive digital control device for analog signal processing that can handle various analog input signals.

According to the present invention, the above object is to integrate various input/output devices including a processing device and an analog input device and mount them on a printed circuit board, and to connect each device mounted on the printed circuit board to a common bus bar. In a digital control device for analog signal processing, which is connected in parallel through a cable and housed in a single housing, there is an analog interface device which is mounted on a printed circuit board and mainly performs level adjustment of the analog input signal, similar to the above-mentioned devices. , and an analog signal bus bar, the interface device and the analog input device are connected via the bus bar and housed in the housing, and the analog input signal within a predetermined level range is transmitted via the analog input device. On the other hand, analog input signals exceeding the predetermined level range are achieved by inputting via the interface device and analog input device. below,
Embodiments of the invention will be described with reference to the drawings.

FIG. 2 is a block diagram showing an embodiment of this invention.
Components that are the same as those in the figures are indicated with the same symbols.

At this company, A
An analog signal Ail input via the I card 5;
Analog interface card (hereinafter also referred to as IF card).

) 7, and an analog signal Ai2 inputted via the analog signal Ai2. The former has an input signal level within a predetermined range and can be input to the quality control device 1 to the extent that analog-to-digital conversion is performed; Conversion or adjustment must be performed, and therefore the analog interface card 7 has a level conversion or adjustment function and, if necessary, an insulation amplification function for removing noise. FIG. 3 is a block diagram showing the overall structure of a digital control device for analog signal processing according to the present invention. A CPU card 1 and various input/output cards 2 to 5 are connected in parallel to each other via bus lines of a motherboard configuration.

In this case, digital input/output and analog output are not considered as a problem, so they are shown together as 2 to 4. Note that each of these cards is arranged in one casing at appropriate intervals. As shown in the diagram, the Ai card 5 is equipped with a multiplexer MPX, an analog-to-digital converter A/D, and an isolation conversion means PC such as a photocoupler. The signal is scanned, selected, converted into a digital signal by an analog/digital converter A/D, noise is removed by an insulation conversion means PC, and then input into the processing device 1.

Also, Ai card. 5 is provided with a setting device S whose value can be changed as appropriate, for example, by manual operation. The data set by this setting device SV is semi-fixed, but it may not be possible to store it in advance as data in the storage device within the processing device, or it may be inappropriate to store it in advance. This type of data can be adjusted even while the system is running. Although not shown in the drawings, the IF card 7 is equipped with an isolation amplifier such as a chopper, a relay, a polyurethane, etc., and has means for adjusting analog input signals at a level that cannot be accommodated in the Ai card 5. These are contained on one card. The bus lines are separated into upper and lower parts, with the upper bus 61 being for digital signals and consisting of a data bus, address bus, control bus, etc., and the lower bus 62 being for analog signals. A for this
An i-card 5 and an IF card 7 are connected via connectors C, respectively. FIG. 4 is a connection circuit diagram showing the connection state of the main parts of the present invention. Hereinafter, how analog signals are inputted will be explained with reference to FIGS. 3 and 4.

Analog input Ail within a predetermined level range is
The signal enters from the front terminal of the Ai card 5 shown in the figure, and is input to the bus line 61 on the back side via the multiplexer MPX, analog/digital converter A/D, and photocoupler PC (omitted in FIG. 4). In addition, ◎ in Figure 4
The marks indicate the terminals on the front side of the card, while the 0 marks indicate the terminals on the back side. Although not clearly shown in the figure, the analog signal from the setting device SV generated inside the Ai card 5 is also routed to the bus line via the multiplexer MPX, analog/digital converter A/D, etc. in the same manner as above. 6
, given to . On the other hand, the analog input signal Ai2 exceeding the predetermined level range enters from the front side terminal of the IF card 7 in FIG. The signal is input to the bus line 61 via an A/D or the like.

In addition, as a special case, there is a case where the data enters from the front side of the IF card 7 and exits from the front side of the IF card again after various analog processing is performed. In the above explanation, the number of Ai cards 5 and IF cards 7 mounted is one per chassis, but the number is not limited to this, and any number of cards may be installed, and the mounting positions may also be as shown in Figure 3. It is not limited to this and may be arranged arbitrarily (free location method).

As described above, according to the present invention, since the IF card 7 can be housed in one housing like other cards, a special external device is provided for preprocessing various analog signals. This is not necessary and therefore not only makes the whole thing more compact, but also greatly reduces costs.

[Brief explanation of drawings]

Fig. 1 is a block diagram showing a conventional example of a digital control device, Figs. 2 to 4 all show embodiments of the present invention, Fig. 2 is a block diagram, Fig. 3 is a block diagram, and Fig. 4 is a block diagram. is a connection circuit diagram of the main parts.

Claims (1)

[Claims] 1. A digital processing device having storage and arithmetic control functions and an analog input device that converts an analog input signal into a digital signal and provides it to the processing device are integrated and mounted on a printed circuit board, respectively, and In a digital control device for analog signal processing, which is made up of devices connected via a common bus bar and housed in one housing, it is mounted on a printed circuit board like the devices mentioned above, and is used to adjust the level of analog input signals and to isolate them. An analog interface device that performs conversion, etc. is provided, the interface device is connected to the analog input device via a second bus bar different from the bus bar, and is housed in the housing, and the interface device is connected to the analog input device through a second bus bar different from the bus bar, and is housed in the housing, and A digital control device for analog signal processing, characterized in that signals within the range are directly introduced into the analog input device, while signals exceeding a predetermined level range are introduced into the analog input device via an interface device.