U.S. patent application number 09/121687 was filed with the patent office on 2001-08-09 for communication device and process.
This patent application is currently assigned to SCHEIDER ELECTRIC SA. Invention is credited to WEYNACHTER, LUC.
Application Number | 20010011956 09/121687 |
Document ID | / |
Family ID | 9510483 |
Filed Date | 2001-08-09 |
United States Patent
Application |
20010011956 |
Kind Code |
A1 |
WEYNACHTER, LUC |
August 9, 2001 |
COMMUNICATION DEVICE AND PROCESS
Abstract
The communication device comprises a central unit and at least
one station connected by a network. The station comprises a
checking circuit and a storage circuit connected to the checking
circuit. The storage circuit stores data representative of
information which the station has to transmit to the central unit
and transmission condition parameters associated to said
information. In a parameter setting phase, the station receives the
data and parameters to be stored. Then, in an operating phase, the
checking circuit transmits information according to the stored
transmission condition parameters.
Inventors: |
WEYNACHTER, LUC; (GRENOBLE,
FR) |
Correspondence
Address: |
SQUARE D COMPANY
INTELLECTUAL PROPERTY DEPARTMENT
1415 SOUTH ROSELLE ROAD
PALATINE
IL
60067
US
|
Assignee: |
SCHEIDER ELECTRIC SA
|
Family ID: |
9510483 |
Appl. No.: |
09/121687 |
Filed: |
July 24, 1998 |
Current U.S.
Class: |
340/870.11 ;
370/252 |
Current CPC
Class: |
H04M 11/002
20130101 |
Class at
Publication: |
340/870.11 ;
370/252 |
International
Class: |
H04J 003/14; H04L
012/26 |
Foreign Application Data
Date |
Code |
Application Number |
Aug 20, 1997 |
FR |
9710631 |
Claims
1. A communication device comprising: a central unit, and at least
one station, wherein at least one station comprises means for
storing data representative of type of information to be
transmitted and means for storing parameters representative of
conditions for transmission of information from the station to the
central unit, associated to the data representative of type of
information to be transmitted.
2. The communication device according to claim 1, wherein at least
one station comprises checking means to transmit information
defined by type of information to be transmitted data according to
the parameters representative of transmission conditions.
3. The communication device according to claim 1, wherein at least
one of the parameters representative of transmission conditions is
representative of transmission of information on a request from the
central unit.
4. The communication device according to claim 1, wherein at least
one of the parameters representative of transmission conditions is
representative of transmission of information according to a preset
variation of an item of information.
5. The communication device according to claim 1, wherein at least
one of the parameters representative of transmission conditions is
representative of transmission of information at preset time
intervals.
6. The communication device according to claim 1, wherein at least
one of the parameters representative of transmission conditions is
representative of transmission of information on an event.
7. The communication device according to claim 2, wherein the
checking means are connected to a device for measuring electrical
quantities.
8. The communication device according to claim 2, wherein the
checking means are connected to an electronic trip device supplying
information representative of electrical quantities and status
information.
9. The communication device according to claim 2, wherein at least
one station comprises storage means for storing information
temporarily.
10. A communication process between a central unit and at least one
station comprising an operating phase comprising: a stage for
checking information transmission conditions according to
transmission condition parameters, and a stage for information
transmission according to checking of transmission conditions.
11. The communication process according to claim 10, wherein at
least one transmission condition parameter is representative of
transmission of information on a request from the central unit.
12. The communication process according to claim 10, wherein at
least one transmission condition parameter is representative of
transmission of information according to a variation of the value
of an item of information.
13. The communication process according to claim 10, wherein at
least one transmission condition parameter is representative of
transmission of information at preset time intervals.
14. The communication process according to claim 10, comprising a
parameter setting phase comprising: a transmission stage by the
central unit to at least one station of data representative of type
of information to be transmitted, and a storage stage in at least
one station of data representative of type of information to be
transmitted.
15. The communication process according to claim 10, comprising a
parameter setting phase comprising: a transmission stage by the
central unit to at least one station of the parameters
representative of information transmission conditions, and a
storage stage in at least one station of the parameters
representative of transmission conditions.
Description
BACKGROUND OF THE INVENTION
[0001] The invention relates to a communication device comprising a
central unit and at least one station, and also to a communication
process between said central unit and said station.
[0002] Known communication devices comprise a central unit and
stations connected via a communication network. Information
exchanges between the stations and the central unit generally take
place according to a master-slave communication mode or
continuously on events.
[0003] In the master-slave exchange mode, the central unit requests
information from a station which replies to it by transmitting the
requested information back to it. This exchange mode has the
advantage of being simple. However, the information flow across the
network becomes high and there is a risk of saturation due to the
double information flow. Indeed, before each item of information
which a station has to transmit to the central unit, there is a
request from the central unit to said station.
[0004] Transmission of information on events does not require a
request from the central unit at each information exchange. In this
exchange mode, a station transmits information to the central unit
of its own accord when an event is detected by said station. This
exchange mode is also simple but the information flow is also
liable to be high. If the quantity of data liable to be transmitted
by the stations is high, the central unit is in fact liable to
receive a large quantity of useless information which congests the
communication network and consequently reduces its
performances.
[0005] The exchange on event mode is well suited to communication
devices in which the stations have a small quantity of information
to transmit. But when the stations are associated in particular to
complex apparatuses such as circuit breakers comprising electronic
trip devices or measuring devices or devices for computing several
electrical quantities, the master-slave or on-event exchange modes
do not allow optimum use of the communication network.
SUMMARY OF THE INVENTION
[0006] The object of the invention is to achieve a communication
device and process enabling optimum use of a communication network
connecting a central unit to stations.
[0007] This object is achieved by the fact that at least one
station comprises means for storing data representative of type of
information to be transmitted and means for storing parameters
representative of conditions for transmission of information from
the station to the central unit, associated to the data
representative of type of information to be transmitted.
[0008] Said at least one station comprises, in particular, checking
means to transmit information defined by type of information to be
transmitted data according to the parameters representative of
transmission conditions.
[0009] Preferably, at least one of the parameters representative of
transmission conditions is representative of transmission of
information on a request from the central unit.
[0010] According to a first alternative embodiment, at least one of
the parameters representative of transmission conditions is
representative of transmission of information according to a preset
variation of an item of information.
[0011] According to a second alternative embodiment, at least one
of the parameters representative of transmission conditions is
representative of transmission of information at preset time
intervals.
[0012] According to a third alternative embodiment, at least one of
the parameters representative of transmission conditions is
representative of transmission of information on an event.
[0013] In a first particular embodiment, the checking means are
connected to a device for measuring electrical quantities.
[0014] In a second particular embodiment, the checking means are
connected to an electronic trip device supplying information
representative of electrical quantities and status information.
[0015] Advantageously, at least one station comprises storage means
for storing information temporarily.
[0016] According to the invention, a communication process between
a central unit and at least one station comprises an operating
phase comprising:
[0017] a stage for checking information transmission conditions
according to transmission condition parameters, and
[0018] a stage for information transmission according to checking
of transmission conditions.
[0019] Preferably at least one transmission condition parameter is
representative of transmission of information on a request from the
central unit.
[0020] According to a first alternative embodiment, at least one
transmission condition parameter is representative of transmission
of information according to a variation of the value of an item of
information.
[0021] According to a second alternative embodiment, at least one
transmission condition parameter is representative of transmission
of information at preset time intervals.
[0022] In a preferred embodiment, the communication process
comprises a parameter setting phase comprising:
[0023] a transmission stage by the central unit to at least one
station of data representative of type of information to be
transmitted, and
[0024] a storage stage in at least one station of data
representative of type of information to be transmitted.
[0025] Advantageously, the communication process comprises a
parameter setting phase comprising:
[0026] a transmission stage by the central unit to at least one
station of the parameters representative of information
transmission conditions, and
[0027] a storage stage in at least one station of the parameters
representative of transmission conditions.
BRIEF DESCRIPTION OF THE DRAWINGS
[0028] Other advantages and features will become more clearly
apparent from the following description of particular embodiments
of the invention given as non-restrictive examples only and
represented in the accompanying drawings in which:
[0029] FIG. 1 represents a known communication device,
[0030] FIG. 2 represents a communication device according to an
embodiment of the invention,
[0031] FIG. 3 represents a communication device according to an
embodiment of the invention comprising a station connected to an
electronic trip device,
[0032] FIG. 4 represents a parameter setting phase of a
communication process according to an embodiment of the
invention,
[0033] FIGS. 5 and 6 represent a first and second operating phase
of communication processes according to embodiments of the
invention.
DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENT
[0034] The communication device of FIG. 1 comprises in known manner
a central unit 1 connected to a communication network 2 and
stations 3 and 4 also connected to the communication network. In
this embodiment, the station 3 is connected to an events detector 5
and the station 4 is connected to events detectors 6 and 7.
[0035] If this communication device operates in master-slave mode,
the central unit 1 requests information from the stations 3 or 4
which reply to it. This exchange mode occupies the network twice at
each information request. Thus, when the data have to be frequently
refreshed in the central unit, the network occupation rate becomes
very high.
[0036] To avoid the problem of double data flow in master-slave
operation, the communication device can operate in exchange on
event mode. In this case, a large quantity of information can be
received by the central unit. Among this information, a large part
is liable not to be systematically used. This flow of useless
information increases the network occupation rate.
[0037] In devices according to embodiments of the invention, the
stations comprise means for checking transmission of information to
the central unit so as to optimize the information flow in the
communication network. Thus, the stations transmit information to
the central unit according to predetermined transmission criteria.
These criteria are associated to items of information or to types
of information. For example, a station can transmit certain
information on a request from the central unit and other
information on occurrence of an event.
[0038] FIG. 2 represents a block diagram of a communication device
according to an embodiment of the invention. A station 8 connected
to the communication network 2 comprises an information
transmission checking circuit 9 connected to the network and a
storage circuit 10 connected to the checking circuit 9. Events
detectors 11 and 12 connected to the checking circuit 9 supply
information to the station.
[0039] The storage circuit 10 stores transmission condition
parameters associated to information or to types of information.
The transmission condition parameters correspond for example to
information transmissions on a request from the central unit, on a
variation of a value of certain variables, at preset time
intervals, or when an event is detected. Thus, the circuit 9 checks
information transmission according to the parameters stored in the
storage circuit.
[0040] The storage circuit parameters can be set either in fixed
manner or in dynamic manner in a parameter setting phase. During
this parameter setting phase, the central unit indicates to the
station concerned the information it has to receive and the
transmission condition parameters associated to each item of
information. In this embodiment, the information flow in the
network is optimized as the station only transmits to the central
unit the necessary information for the application for which it is
intended.
[0041] If the application of the central unit changes, the
information and the parameters for information transmission from
the station to the central unit can be changed in another parameter
setting phase.
[0042] FIG. 3 represents an embodiment of a device according to the
invention comprising a station 13 associated to an electronic trip
device 14 of a circuit breaker 15. The electronic trip device
comprises a processing unit 16 connected to the station 13. This
processing unit receives signals representative of currents,
signals representative of voltages, and for example signals
representative of the status of the electrical contacts. The
processing unit supplies an opening order of the circuit breaker
main contacts according to the signals it receives.
[0043] The processing unit computes a large number of electrical or
physical quantities according to the signals representative of
currents or voltages. These quantities are in particular rms, peak
or mean values, and also harmonics, currents or voltages power
values, phase difference values or values of the electrical energy
supplied via the circuit breaker; values representative of tripping
functions on fault currents or temperature rises. All of these
quantities and others, in particular representative of settings of
the processing unit such as thresholds or time delays, can be
transmitted to the central unit 1 via the station 13.
[0044] In a parameter setting phase, the central unit transmits to
the station data representative of the information it has to
receive and transmission condition parameters associated to the
information. The data and parameters are stored in the circuit 10
to be used by the checking circuit 9. Then, during the operating
phase, the processing unit transmits to the station the quantities
it disposes of in the form of information. The checking circuit
transmits information to the central unit according to the
parameters stored in the storage circuit 10. The station can
advantageously comprise a buffer circuit 20 for temporary storage
of the information supplied by the processing unit.
[0045] In the embodiment of FIG. 3, in the parameter setting phase,
the central unit can for example request to receive contact opening
or closing information as soon as these events occur, voltage or
current variation information when these are detected by the
checking circuit, electrical power information at preset time
intervals or phase difference values when the central unit requests
them.
[0046] In order to optimize the information flow in the network,
the information which the central unit requires frequently or
rapidly is transmitted automatically by the station on an event or
at a preset time interval, and the information which concerns the
central unit randomly or which does not have to be frequently
refreshed is preferably transmitted on a request from the central
unit.
[0047] FIG. 4 represents a flowchart of a parameter setting phase
of a communication process according to the invention.
[0048] In a stage 21, the central unit transmits to the station
data representative of the information or types of information it
has to receive. Then, in a stage 22, this data is stored in the
station. Then, in a stage 23, the central unit transmits
transmission condition parameters to the station, and these
parameters are stored in a stage 24.
[0049] Stages 21 and 23 can also be grouped in a single stage where
the data representative of the information and the transmission
condition parameters are transmitted in a single frame. In this
case, the data and parameters are stored, for example, in the order
of their receipt by the station.
[0050] The flowchart of FIG. 5 represents an operating phase in an
embodiment of a process according to the invention. In a stage 25,
information is supplied to the station. This information represents
for example electrical quantities or events such as opening of
contacts or tripping of a circuit breaker. Then, in a stage 26, the
checking circuit determines according to the stored data and
parameters whether information has to be transmitted and under what
conditions. Thus, if transmission conditions are comprised with,
the station transmits the information in a stage 27.
[0051] FIG. 6 represents a detailed flowchart of an operating phase
of a station. In a first stage 28, the checking circuit checks
whether an information item has to be transmitted on a request from
the central unit, then transmits said information if the condition
is complied with. In a stage 30, the checking circuit checks
whether the value of an information item has varied from a preset
value, then it transmits said information to the central unit
(stage 31) if this variation is effective. Then, in a stage 32, the
checking circuit waits for preset time intervals before
transmitting information concerned by said intervals to the central
unit in a stage 33.
[0052] The transmission conditions described above are not
restrictive. Other transmission conditions can be used in other
embodiments. These conditions may be complex. For example, a
transmission condition may be a combination of several conditions.
Likewise, an information item may be transmitted according to
several distinct criteria for example, on a request from the
central unit and according to a preset time interval.
[0053] The events detectors 6, 7, 11 and 12 represent all the
applications associated to the stations and able to generate
information to be transmitted to the central unit. These detectors
may be electronic trip devices as in FIG. 3, relays, measuring
devices, or other monitoring devices.
* * * * *