DE10321842B3 - Sensor or actuator operating method monitors field produced by resonance winding converting magnetic field into electrical energy during operation of electronic communications device for preventing interference - Google Patents

Abstract

The operating method uses a resonance winding (4,5,6) and a rectifier (10,11,12) for providing electrical energy from a magnetic field and an electronic communications device (17) with a radio transmitter and/or receiver for transmission and/or reception of information signals. The field provided by the resonance winding is monitored during the operating periods of the communications device, for preventing interference caused by operation of the sensor or actuator, e.g. by connecting a load (19) across the output terminals of the rectifier. An independent claim for a device for operation of a sensor or actuator is also included.

Description

The The invention relates to a method for operating a sensor or actuator according to the preamble of claim 1. The invention further relates to devices for operating a sensor or actuator according to the preamble of claims 6 and 11th

The Invention can be used, for example, in a system with a large number wireless sensors and / or actuators (wireless both with regard to Energy supply as well as in terms of communication) which are in a machine or system, for example industrial robots, Manufacturing machine, manufacturing machine or process plant installed is. Proximity switches / proximity sensors, Temperature measuring sensors, pressure measuring sensors, current measuring sensors or Voltage measurement sensors or micromechanical, piezoelectric, electrochemical, magnetostrictive, electrostatic or electromagnetic actuators be used.

• – wobei jeder Näherungssensor mindestens eine zur Energieaufnahme aus einem mit telfrequenten Magnetfeld geeignete Sekundärwicklung aufweist,
• – wobei mindestens eine von einem mittelfrequenten Oszillator gespeiste, ein Magnetfeld erzeugende Primärwicklung zur drahtlosen Versorgung der Näherungssensoren mit elektrischer Energie vorgesehen ist,
• – und wobei jeder Näherungssensor mit einer Sendeeinrichtung ausgestattet ist, welche interessierende Sensor-Informationen beinhaltende Funksignale an eine zentrale, mit einem Prozessrechner der Maschine verbundene Basisstation abgibt.

In the DE 199 26 799 A1 a system for a machine having a plurality of wireless proximity sensors, in particular a production machine, is proposed,

• Each proximity sensor has at least one secondary winding suitable for absorbing energy from a telfrequency magnetic field,
• At least one primary winding fed by a medium-frequency oscillator and generating a magnetic field is provided for the wireless supply of the proximity sensors with electrical energy,
• - And wherein each proximity sensor is equipped with a transmitting device which transmits radio signals containing the sensor information of interest to a central base station connected to a process computer of the machine.

The required primary winding includes a relatively large area and often consists of only a few turns, possibly from a single turn. In comparison with this wireless system to conventional solutions with wire / cable connection for electrical power supply and for communication through planning, material, installation, documentation and maintenance-related relatively high cost factor of the wire / cable connections. It can no failures due to cable breaks or bad, for example corroded contacts occur.

In the DE 199 26 562 A1 A method and an arrangement for the wireless supply of a plurality of actuators with electrical energy, an actuator and a primary winding therefor as well as a system for a machine having a plurality of actuators are proposed, the proposed technology with regard to energy supply and communication being similar to that for the above DE 199 26 799 A1 specified technology.

In such wireless power transmission systems, based on self-resonance, generating a magnetic field Primary windings are the units, sensors and / or actuators to be fed in from surrounded a magnetic field with a relatively large magnetic field strength. The sensors and / or actuators have secondary windings, which also operated in natural resonance and such a conversion magnetic Realize energy in electrical energy. In doing so, they produce secondary windings itself a local magnetic and also an electric field, that in the immediate vicinity of the secondary windings is relatively strong.

The Sensors and / or actuators are subject to strict requirements of their compact structure so that it is desirable and often cannot be avoided electronic devices, in particular electronic communication devices (especially radio transmitters and / or radio receivers) for wireless transmission of information signals between the sensors and / or actuators on the one hand and a base station on the other hand in relatively narrow Neighborhood to the secondary windings to arrange. However, there is a risk of interference with the electronic communication devices through that of the sensor or actuator locally generated magnetic and / or electrical Field.

From the DE 691 06 161 T2 A batteryless transponder for transmitting stored measurement data to an interrogation device is known, which transmits an HF interrogation pulse to retrieve the stored measurement data, with a resonance circuit tuned to the frequency of the HF interrogation pulse, an energy storage element that can be charged by rectifying the HF interrogation pulse and supplies the supply voltage for the transponder in the charged state, and a voltage limitation for limiting the voltage on the energy storage element to a predetermined voltage value, with the resonance circuit for detuning its resonance frequency, a component (e.g. capacitor) with frequency-dependent impedance via a switching element (e.g. B. switching transistor) can be connected, which establishes the connection depending on the onset of the limiter effect by the voltage limiting device. By detuning the resonance circuit, that the energy storage element is no longer charged, thereby preventing that too much excess energy in the transponder has to be converted into heat, which can lead to a falsification of the data obtained.

The The invention is based on the object of a method and a device to operate a sensor or actuator, with the help of which disorder the electronic communication device reliably prevented becomes.

This Task is regarding the procedure in connection with the characteristics of the preamble according to the invention solved the features specified in the characterizing part of claim 1.

The Task is regarding the device in connection with the Characteristics of the generic term alternatively by those in the indicator of claims 6 and 11 specified features.

The Advantages achievable with the invention consist in particular in that an arrangement of electronic communication devices, in particular Radio transmitter and radio receiver, close to the secondary windings of the energy supply system possible is, so that a compact structure of the sensor or actuator is promoted. Special shielding measures, which often have the disadvantage of being complicated and expensive to be (since mostly special adjustments for each individual sensor and Actuator are required) not be hit.

Further Advantages are evident from the description below.

advantageous Embodiments of the invention are characterized in the subclaims.

The Invention is illustrated below with reference to that in the drawing Exemplary embodiments explained: It demonstrate:

1 a system with a large number of wireless sensors and / or actuators,

2 . 3 . 4 a sensor or actuator with energy generation and communication device according to a first embodiment in three different variants,

5 a sensor or actuator with energy generation and communication device according to a second embodiment.

In 1 shows a system with a large number of wireless sensors and / or actuators. The wireless sensors and / or actuators 1.1 . 1.2 . 1.3 ... 1.n are, for example, construction components of a production robot. A magnetic field generation system 2 - resonance-operated primary coils and associated energy feed circuits - produces this for the wireless energy supply of the sensors and / or actuators 1.1 ... 1.n required magnetic field. The sensors and / or actuators 1.1 ... 1.n each have an electronic communication device (see reference number 17 in the 2 and 3 ) on the radio signals with a communication base station 3 communicate, which is expediently connected to a central computer (process computer, programmable logic controller). Each communication device preferably has a radio transmitter and a radio receiver, each including an antenna, in order, for example, to be able to transmit sensor signals from the sensors and signaling signals relating to the current state of actuators to the base station and, for example, to trigger signals for activating / deactivating actuators and signals for setting to be able to receive specific parameters of the actuators and sensors from the base station.

The sensors and / or actuators contain an energy generating device or energy supply unit which serves to supply the sensor components or actuator components and to supply the communication device, such as modulator / encoder, radio transmitter, radio receiver, demodulator / decoder. This energy supply unit consists of at least one secondary winding, a resonance capacitor arranged in parallel or in series, a rectifier and an energy store at the DC output of the rectifier. The energy supply of the secondary winding takes place by magnetic coupling from the magnetic field generation system 2 produced magnetic field.

In the 2 . 3 . 4 a sensor or actuator with energy generation and communication device according to a first embodiment is shown. It is a rectifier 10 to recognize its alternating connections with a parallel connection of a secondary winding 4 with a resonance capacitor 7 is connected (parallel resonance circuit). In the same way lie on the change connections of a rectifier 11 the parallel connection of a secondary winding 5 with a resonance capacitor 8th or on the alternating connections of a rectifier 12 the parallel connection of a secondary winding 6 with a resonance capacitor 9 , The winding axes of the three secondary windings operated in resonance 4 . 5 . 6 are arranged at right angles to each other and intersect in a center len point of a core of the three-dimensional winding arrangement constructed from a magnetically active material (of course, alternative versions without a core can also be realized as an alternative). The from the secondary windings 4 respectively. 5 respectively. 6 and the resonance capacitors 7 respectively. 8th respectively. 9 The circles formed are also referred to below as secondary-side resonance circles.

The DC connections of all rectifiers 10 . 11 . 12 are connected in parallel and with one load 16 (= the components of the sensor and / or actuator to be supplied with energy), for example a sensor measuring unit + sensor electronics + communication device 17 a sensor or a control unit + communication device 17 of an actuator connected. Between the DC connections of the rectifiers connected in parallel 10 . 11 . 12 is a backup capacitor 13 arranged.

As already mentioned above, is an electronic communication device 17 Part of the load 16 , During the operating time of this communication device 17 (Send / receive), more precisely a short period of time before the start of the operation until the end of the operation, controls the communication device 17 according to one in 2 shown first variant of the first embodiment, a switch 18 so that the rectifiers connected in parallel 10 . 11 . 12 subsequently no longer with the load 16 but with the load 19 are connected. As a switch 18 can serve, for example, a transistor configuration.

Of course, instead of a switch 18 also one out of two switches 18 ' . 18 '' formed configuration can be used, as in the second variant of the first embodiment in 3 is shown with a switch 18 ' with the load 16 and a switch 18 '' with the load 19 connected is. Both switches 18 ' . 18 '' are from the communication facility 17 controlled so that during the operating times of the communication device 17 switch 18 '' closed and switch 18 ' open as well as switches in the remaining periods 18 ' closed and switch 18 '' is open.

According to one in 4 shown third variant of the first embodiment is in place of a switch 18 ' a diode 18 ' used so that during the operating hours of the communication device 17 switch 18 '' is closed and open in the remaining periods. Due to the anode and cathode of the diode 18 ' existing potential is automatically ensured that the diode 18 ' during the operating times of the communication device 17 is in the blocked state and in the on state during the remaining periods.

Weight 19 is to be interpreted in all variants in such a way that the load 19 conducted secondary current flow is higher than that via the circuit with load 16 guided secondary current flow. On the one hand, this serves the purpose in the secondary resonance circuits 4 / 7 ; 5 / 8th ; 6 / 9 even before the operating time of the communication device begins 17 to discharge / dissipate existing stored energy quickly and on the other hand to do this, which additionally during the operating time of the communication device 17 dissipate / dissipate energy.

Preferably a load 19 with low ohmic resistance compared to load 16. In extreme cases, the load 19 be a very low-resistance bridge (quasi a short-circuit bridge), so that there is quasi a "low-resistance short circuit" of the secondary rectifier series circuit.

Alternatively, a capacitor can also be used as a load 19 be used, which also increases the secondary current flow during operation of the communication device 17 causes. The capacitor is to be designed in such a way that a charging cycle takes considerably longer than an operating time of the communication device.

In 5 a sensor or actuator with energy generation and communication device according to a second embodiment is shown. It is the rectifier again 10 to recognize its alternating connections with a parallel connection of a secondary winding 4 with a resonance capacitor 7 and an additional component (capacitor or choke) 20 is connected (parallel resonance circuit). In the same way lie on the changeover connections of the rectifier 11 the parallel connection of a secondary winding 5 with a resonance capacitor 8th and an additional component (capacitor or choke) 21 or on the alternating connections of a rectifier 12 the parallel connection of a secondary winding 6 with a resonance capacitor 9 and an additional component (capacitor or choke) 22 , The winding axes of the three secondary windings operated in resonance 4 . 5 . 6 are in turn arranged at right angles to each other and intersect at a central point of a core of the three-dimensional winding arrangement constructed from a magnetically active material (of course, alternative versions without a core can also be realized as an alternative). In series with every additional component (capacitor or choke) 20 respectively. 21 respectively. 22 is a switch 23 respectively. 24 respectively. 25 arranged. As a switch 23 . 24 . 25 For example, transistors can be used.

The DC connections of all rectifiers 10 . 11 . 12 are connected in parallel and with one load 16 (= the components of the sensor and / or actuator to be supplied with energy), for example a sensor measuring unit + sensor electronics + communication device 17 a sensor or a control unit + communication device 17 of an actuator connected. Between the DC connections of the rectifiers connected in parallel 10 . 11 . 12 is a backup capacitor 13 arranged.

As already mentioned above, the electronic communication device 17 Part of the load 16 , During the operating time of this communication device 17 (Transmit / receive), more precisely a short period before the start of operation until the end of operation, the switches 23 . 24 . 25 by corresponding control signals of the communication device 17 closed. The switches are in the remaining periods 23 . 24 . 25 opened so that the additional components (capacitor or choke) 20 . 21 . 22 are irrelevant and the resonance currents in the secondary resonance circuits 4 / 7 ; 5 / 8th ; 6 / 9 train with a predetermined resonance frequency.

With switches closed 23 . 24 . 25 there is a change in the resonance frequencies of the electrical resonance circuits then formed on the secondary side 4 / 7 / 20 ; 5 / 8th / 21 ; 6 / 9 / 22 , a reduction in the quality factors and consequently a considerable reduction in the currents flowing in the circles, ie the currents of the winding arrangement are weakened in those periods in which the communication device 17 is operated. Consequently, there is a substantial weakening of the local windings from the secondary windings during the operating times of the communication device 4 . 5 . 6 generated magnetic and electrical fields. Such a measure corresponds to a detuning of an electrical resonant circuit.

Of course, the sensors and / or actuators 1.1 ... 1.n other embodiments for the generation of electrical energy from a magnetic field can also be implemented; this is expressly referred to in the DE 100 55 404 A1 in the 4 . 5 . 6 and 8th explained variants pointed out which series resonance circuits, parallel resonance circuits, series-connected DC connections of the rectifiers, parallel DC connections of the rectifiers and transformers used treat.

• • Es kann eine Schwächung des Feldes während Zeitspannen erfolgen, in denen aktiv ein Empfang/Senden von Funksignalen erfolgt.
• • Zusätzlich kann eine Schwächung des Feldes während Zeitspannen erfolgen, in denen ein Sensorbetrieb (Erfassung interessierender Messgrößen) erfolgt.

The periods in which the above-described weakening of the field generated locally by the secondary windings takes place can vary depending on the specific application and the specific conditions:

• • The field can be weakened during periods in which radio signals are actively received / transmitted.
• • In addition, the field can be weakened during periods in which sensor operation (acquisition of relevant measured variables) takes place.

Generally expressed will that be local - d. H. in the secondary windings - generated Field by reducing the secondary resonance current in reduced in those periods in which the communication system or other electronic systems used (e.g. measuring systems) sensitive to interference fields react. This is done through change the resonance frequency due to modification of electrical quantities Resonance components or due to increased load on the output side of the resonance circuit.

1

1.1 . 1.2 . 1.3 ... 1.n : Sensors and / or actuators

2

Magnetic field generation system

3

Communication base station

4

secondary winding

5

secondary winding

6

secondary winding

7

resonant capacitor

8th

resonant capacitor

9

resonant capacitor

10

rectifier

11

rectifier

12

rectifier

13

backup capacitor

14

15

16

load (e.g. sensor measuring unit, sensor electronics)

17

communicator

18

Switch, 18 ' and 18 '' Switch, 18 ' diode

19

load

20

Additional structural component (Capacitor or choke)

21

Additional structural component (Capacitor or choke)

22

Additional structural component (Capacitor or choke)

23

switch

24

switch

25

switch

Claims (13)

Method for operating a sensor or actuator ( 1.1 . 1.2 ... 1.n ) with resonance-operated winding arrangement ( 4 . 5 . 6 . 7 . 8th . 9 ) and downstream rectifier ( 10 . 11 . 12 ) to generate electrical energy from a magnetic field and with an electronic communication device ( 17 ) with radio transmitter and / or radio receiver for Delivery and / or reception of information signals, characterized in that the winding arrangement ( 4 . 5 . 6 . 7 . 8th . 9 ) self-produced field is weakened in those periods in which the communication device ( 17 ) is operated. A method according to claim 1, characterized in that a load (to weaken the field produced ( 19 ) to the output terminals of the rectifier ( 10 . 11 . 12 ) during the operating hours of the communication device ( 17 ) is switched, which load ( 19 ) for rapid discharge of the stored energy of the resonance circuit with winding arrangement ( 4 . 5 . 6 . 7 . 8th . 9 ) leads and which during the operating time of the communication device ( 17 ) through the winding arrangement ( 4 . 5 . 6 . 7 . 8th . 9 ) degrades generated energy. A method according to claim 2, characterized in that the components to be supplied with energy ( 16 ) of the sensor and / or actuator including the communication device ( 17 ) from the winding arrangement ( 4 . 5 . 6 . 7 . 8th . 9 ) with downstream rectifier ( 10 . 11 . 12 ) during the operating times of the communication device ( 17 ) be separated. A method according to claim 1, characterized in that a detuning of the resonance circuit with winding arrangement (to weaken the field produced 4 . 5 . 6 . 7 . 8th . 9 ) during the operating hours of the communication device ( 17 ) he follows. Method according to one of the preceding claims, characterized in that the winding arrangement ( 4 . 5 . 6 . 7 . 8th . 9 ) self-produced field is weakened in those periods in which sensor operation takes place. Device for operating a sensor or actuator ( 1.1 . 1.2 ... 1.n ) with resonance-operated winding arrangement ( 4 . 5 . 6 . 7 . 8th . 9 ) and downstream rectifier ( 10 . 11 . 12 ) to generate electrical energy from a magnetic field and with an electronic communication device ( 17 ) with radio transmitter and / or radio receiver for delivering and / or receiving information signals, characterized in that the output terminals of the rectifier ( 10 . 11 . 12 ) via a switch ( 18 '' ) or switch ( 18 ) optionally with a load increasing the output current of the rectifier ( 19 ) can be connected, the communication device ( 17 ) this switch during their operating hours ( 18 '' ) or switch ( 18 ) controls. Apparatus according to claim 6, characterized in that the output terminals of the rectifier ( 10 . 11 . 12 ) via another switch ( 18 ' ) or the switch ( 18 ) with the components to be supplied with energy ( 16 ) of the sensor and / or actuator including the communication device ( 17 ) connected is. Apparatus according to claim 6, characterized in that the output terminals of the rectifier ( 10 . 11 . 12 ) via a diode ( 18 ' ) with the components to be supplied with energy ( 16 ) of the sensor and / or actuator including the communication device ( 17 ) connected is. Device according to one of claims 6-8, characterized by an essentially ohmic load ( 19 ). Device according to one of claims 6-8, characterized by an essentially capacitive load ( 19 ). Device for operating a sensor or actuator ( 1.1 . 1.2 ... 1.n ) with resonance-operated winding arrangement ( 4 . 5 . 6 . 7 . 8th . 9 ) and downstream rectifier ( 10 . 11 . 12 ) to generate electrical energy from a magnetic field and with an electronic communication device ( 17 ) with radio transmitter and / or radio receiver for the delivery and / or reception of information signals, characterized in that one by means of a switch ( 23 . 24 . 25 ) switchable additional component ( 20 . 21 . 22 ) in the resonant circuit with winding arrangement ( 4 . 5 . 6 . 7 . 8th . 9 ) is arranged, the communication device ( 17 ) this switch ( 23 . 24 . 25 ) activated during their operating hours. Apparatus according to claim 11, characterized by a capacitor as a switchable additional component ( 20 . 21 . 22 ). Apparatus according to claim 11, characterized by a throttle as a switchable additional component ( 20 . 21 . 22 ).