[go: up one dir, main page]

EP0895264B1 - Stromregler für eine induktive Last - Google Patents

Stromregler für eine induktive Last Download PDF

Info

Publication number
EP0895264B1
EP0895264B1 EP19980305816 EP98305816A EP0895264B1 EP 0895264 B1 EP0895264 B1 EP 0895264B1 EP 19980305816 EP19980305816 EP 19980305816 EP 98305816 A EP98305816 A EP 98305816A EP 0895264 B1 EP0895264 B1 EP 0895264B1
Authority
EP
European Patent Office
Prior art keywords
current
interval
duration
average value
voltage comparator
Prior art date
Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
Expired - Lifetime
Application number
EP19980305816
Other languages
English (en)
French (fr)
Other versions
EP0895264A1 (de
Inventor
Stephen Potter
Simon Turvey
Current Assignee (The listed assignees may be inaccurate. Google has not performed a legal analysis and makes no representation or warranty as to the accuracy of the list.)
ZF International UK Ltd
Original Assignee
Lucas Industries Ltd
Priority date (The priority date is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the date listed.)
Filing date
Publication date
Application filed by Lucas Industries Ltd filed Critical Lucas Industries Ltd
Publication of EP0895264A1 publication Critical patent/EP0895264A1/de
Application granted granted Critical
Publication of EP0895264B1 publication Critical patent/EP0895264B1/de
Anticipated expiration legal-status Critical
Expired - Lifetime legal-status Critical Current

Links

Images

Classifications

    • H—ELECTRICITY
    • H01—ELECTRIC ELEMENTS
    • H01H—ELECTRIC SWITCHES; RELAYS; SELECTORS; EMERGENCY PROTECTIVE DEVICES
    • H01H47/00—Circuit arrangements not adapted to a particular application of the relay and designed to obtain desired operating characteristics or to provide energising current
    • H01H47/22—Circuit arrangements not adapted to a particular application of the relay and designed to obtain desired operating characteristics or to provide energising current for supplying energising current for relay coil
    • H01H47/32—Energising current supplied by semiconductor device
    • H01H47/325—Energising current supplied by semiconductor device by switching regulator

Definitions

  • This invention relates to a current control for an inductive load.
  • the force produced by an electro-mechanical actuator in which there is a cyclically fluctuating current is a function of the average magnetic flux in the air gap of the actuator and hence is related to the average current flowing in the actuator winding (or windings).
  • To control an actuator to give a particular force therefore it is advantageous to maintain a correct level of average current in the winding(s) to provide reliable actuation without excessive power consumption.
  • Efficient operation of electro-mechanical actuators is conventionally achieved by using pulse width modulation of the voltage supply to the actuator. This involves closing a switch element periodically to cause current in the winding(s) to increase and then opening the switch to allow the current to be diverted through a recirculation diode or other recirculation element, so that the current decays until the next pulse is commenced.
  • a recirculation diode or other recirculation element it is difficult in conventional control circuits to measure the average current flow, since the current sensing element required has to be able to monitor the current during both current growth and current decay periods.
  • the recirculation diode is separate from the winding, this is possible, but complex and expensive analog circuit elements will be required to effect the monitoring. Where the recirculation diode is built into the winding and has no separate terminals, current metering is even more difficult.
  • a current control for an inductive load comprising a switch device and a current sensing element connected in series with the load, a voltage comparator connected to the sensing element and arranged to operate when the current in said sensing element is equal to a desired average value, and a digital control circuit connected to said voltage comparator to receive an input therefrom and to said switch device to control the state of conduction thereof, said digital control circuit operating to turn said switch device on periodically, to measure the duration of a first interval from turn-on to the moment of operation of the voltage comparator when the current in the load reaches the desired average value, and to maintain the switch element in its turned-on condition for a second interval of duration calculated as a function of the duration of said first interval.
  • the growth and decay can be regarded as substantially linear, so that an acceptable level of accuracy can be obtained by basing the duration of the second interval on the duration of the first.
  • the calculation used is such that, in steady state conditions, the duration of the second interval is equal to the duration of the first interval.
  • the calculation is such that the duration of the second interval is equal to the average of the durations of the first intervals in the current cycle and the preceding cycles.
  • the inductive load is in the form of a solenoid 10 with which there is associated a current recirculation diode 10a.
  • This diode is, in fact, built into the solenoid so that it is not possible to separate the connections between the solenoid and the diode, thereby making it impossible to use a current sensing element which can sense the current level in the solenoid when externally supplied current is interrupted.
  • the control includes a field effect transistor switch device 11 and a current sensing resistor 12 connected in series with the solenoid between a supply rail 13 and a ground rail 14. One end of the resistor 12 is connected to the supply rail 13, so that the voltage at the other end of the resistor is linearly related to the current flowing in the solenoid when the switch device 11 is conductive.
  • the control also includes a voltage comparator 15 which has its inverting input connected by a resistor 16 to said other end of the resistor 12 and to the supply rail 17 (acting as a noise filter) to the supply rail 13.
  • the output terminal of the voltage comparator 15 is connected to an input terminal of an ASIC 18 which incorporates an arithmetic unit (not shown).
  • the ASIC has one output terminal which is connected by a resistor 19 to the gate of the switch device 11.
  • Another output terminal of the ASIC provides a reference voltage to the non-inverting input terminal of the voltage comparator 15 in accordance with commands received by the ASIC and calculations made in the arithmetic unit thereof.
  • the generation of the reference voltage is not described in detail herein but can be set dynamically and statically to minimise the actuator power consumption.
  • the reference voltage applied to the non-inverting input of the voltage comparator 15 is set to the voltage to which said other end of the resistor 12 will drop when the instantaneous current flowing in the resistor 12 is equal to the desired average current in the solenoid 10.
  • the relevant part of the program of the ASIC is shown in Figure 3.
  • the routine shown is called periodically at set time intervals and is responsible for monitoring the output of the voltage comparator and controlling the switch device accordingly.
  • Each time the routine is called the variable t is incremented (20) and the value of t is compared (21) with the repetition cycle time t cyc . If the cycle time has not expired the routine tests (22) whether the system is in the first phase of its cycle. If it is, then the routine tests (23) whether the output of the voltage comparator 15 is high or low. If the output is low the routine terminates. If it is high, a calculation (24) is carried out to update the stored value of a variable t av by adding three times the stored value to the current value of t and dividing the sum by 4.
  • t off is then calculated as the sum of the new value of t av and t .
  • the value of the phase variable is then set (25) to 2 so that on the next cycle, decision (22) will cause a jump to a different branch of the routine.
  • phase is equal to 2
  • the routine tests (26) whether the period defined by the variable t off has expired. If it has, then phase is set (27) to 3 and the switch is turned off.
  • phase When phase is set to 3, the routine tests (29) whether t cyc has expired. If it has t is set to zero, phase is set to 1, and the switch is turned on.
  • the switch device 11 is turned on at the beginning of the cycle.
  • the current level thus starts to rise.
  • the output of the voltage comparator 15 goes high and the duration of the on period of the switch is then calculated.
  • the switch is held on until the (second) calculated period expires, and then the switch device is turned off again until it is time for a new cycle to commence.
  • the inclusion in the calculation of the total on time of a dominant term based on previous durations of the first interval ensures that the control adjusts itself to the changed conditions in a stable manner.
  • the solenoid 10 is connected between the supply rail 13 and the switch device 11.
  • the resistor 12 is connected between the switch device 11 and the ground rail 14 and it is the non-inverting input of the voltage comparator 15 which is connected by resistor 16 to the resistor 12.
  • the inverting input of the voltage comparator 15 is connected to receive the reference voltage signal from the ASIC 18.

Landscapes

  • Engineering & Computer Science (AREA)
  • Power Engineering (AREA)
  • Electronic Switches (AREA)
  • Control Of Voltage And Current In General (AREA)

Claims (5)

  1. Stromregelung für eine induktive Last (10), aufweisend eine Schaltvorrichtung (11) und ein Stromfühlelement (12), die in Serie zu der Last angeschlossen sind, einen Spannungskomparator (15), der mit dem Fühlelement verbunden ist, und ausgelegt ist, um zu wirken, wenn der Strom in dem Fühlelement gleich einem gewünschten mittleren Wert ist, und eine digitale Regelschaltung (18), die mit dem Spannungskomparator verbunden ist, um ein Eingangssignal von dem Spannungskomparator zu erhalten, und mit der Schaltvorrichtung verbunden ist, um den Leitungszustand der Schaltvorrichtung zu steuern, wobei die digitale Regelschaltung (18) wirksam ist, um die Schaltvorrichtung periodisch einzuschalten, um die Dauer eines ersten Intervalls von dem Einschalten bis zu dem Augenblick des Betriebs des Spannungskomparators, in dem der Strom in der Last den gewünschten mittleren Wert erreicht, zu messen, und um das Schaltelement während eines zweiten Intervalls von einer Dauer, die als eine Funktion der Dauer des ersten Intervalls berechnet wird, in seinem eingeschalteten Zustand zu halten.
  2. Stromregelung wie in Anspruch 1 beansprucht, bei der die digitale Regelschaltung (18) so wirkt, daß in einem stabilen Zustand die Dauer des zweiten Intervalls so eingestellt wird, daß es gleich der gemessenen Dauer des ersten Intervalls ist.
  3. Stromregelung wie in Anspruch 2 beansprucht, bei der die digitale Regelschaltung (18) eine Variable beibehält, die den mittleren Wert der Dauer des ersten Intervalls repräsentiert, und diese Variable jedesmal aktualisiert, wenn ein neuer Wert für die Dauer des ersten Intervalls bestimmt wird.
  4. Stromregelung wie in Anspruch 3 beansprucht, bei der die Aktualisierung des mittleren Wertes entsprechend dem Ausdruck tav = (3*t'av + t)/4 ausgeführt wird, wo tav der neue mittlere Wert ist, t'av der alte mittlere Wert ist, und t die neue gemessene Dauer des ersten Intervalls ist.
  5. Stromregelung wie in irgendeinem vorhergehenden Anspruch beansprucht, bei der die digitale Regelschaltung (18) ein Signal, das den gewünschten mittleren Wert repräsentiert, auf den Spannungskomparator gibt.
EP19980305816 1997-08-01 1998-07-21 Stromregler für eine induktive Last Expired - Lifetime EP0895264B1 (de)

Applications Claiming Priority (2)

Application Number Priority Date Filing Date Title
GBGB9716220.0A GB9716220D0 (en) 1997-08-01 1997-08-01 Current control for an inductive load
GB9716220 1997-08-01

Publications (2)

Publication Number Publication Date
EP0895264A1 EP0895264A1 (de) 1999-02-03
EP0895264B1 true EP0895264B1 (de) 2000-02-23

Family

ID=10816778

Family Applications (1)

Application Number Title Priority Date Filing Date
EP19980305816 Expired - Lifetime EP0895264B1 (de) 1997-08-01 1998-07-21 Stromregler für eine induktive Last

Country Status (3)

Country Link
EP (1) EP0895264B1 (de)
DE (1) DE69800081T2 (de)
GB (1) GB9716220D0 (de)

Families Citing this family (3)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
EP1347562B1 (de) * 2002-03-13 2011-07-06 Continental Automotive GmbH Verfahren zum Steuern oder Regeln des Stromflusses durch einen induktiven Verbraucher
US7667446B2 (en) 2007-01-11 2010-02-23 Infineon Technologies Ag Method for controlling current in a load
US7872845B2 (en) 2007-03-30 2011-01-18 Infineon Technologies Ag Control system

Family Cites Families (3)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US4481554A (en) * 1983-08-18 1984-11-06 Towmotor Corporation Voltage adaptive solenoid control apparatus
DE3904441A1 (de) * 1987-08-12 1990-08-23 Mannesmann Ag Chopperschaltung fuer die ansteuerung von elektromagnet- und/oder schrittmotoren-spulen, insbesondere fuer einen matrixdrucker
GB9006973D0 (en) * 1990-03-28 1990-05-23 Vickers Systems Ltd Digital pulse-width-modulation generator for current control

Also Published As

Publication number Publication date
DE69800081D1 (de) 2000-03-30
GB9716220D0 (en) 1997-10-08
DE69800081T2 (de) 2000-09-14
EP0895264A1 (de) 1999-02-03

Similar Documents

Publication Publication Date Title
US4764840A (en) Dual limit solenoid driver control circuit
US20100157635A1 (en) Predictive current control in driving a load in a pwm mode
US6661216B1 (en) Apparatus and method for controlling startup of a precharged switching regulator
KR20020093031A (ko) 전력 제어 애플리케이션을 위한 이중 모드 펄스-폭 변조기
US20090140749A1 (en) Device for Measuring a Load Current
JPH02295016A (ja) 少なくとも１つの電磁リレーの制御回路装置
US20170302180A1 (en) Dc-dc converter
US8093882B2 (en) Low heat dissipation I/O module using direct drive buck converter
US7733073B2 (en) Current regulator with current threshold dependent duty cycle
EP0895264B1 (de) Stromregler für eine induktive Last
GB2152305A (en) Circuit arrangement for controlling and monitoring electrical loads
US7015716B2 (en) Method for detecting a power load of a power supply module according to duty cycle detection, and related device
EP0685744B1 (de) Gerät zur Messung elektrischer Energie mit einem Multiplexer
US6142124A (en) Method and device for controlling a load
US20220107336A1 (en) Magnetic-field sensor device
US20030141764A1 (en) Real-time digital voltage sag compensator
CA2766758C (en) Active core current sensor
KR20160030458A (ko) 솔레노이드 작동체를 제어하는 방법 및 디바이스
JP2003189598A (ja) スイッチング電源装置
JPH08110246A (ja) パラメータ測定回路
US6583615B1 (en) Magnetostrictive sensor device having one interface providing information regarding mode converter signal volatage and sensed object position
CA1108720A (en) Periodic engine speed monitoring circuit utilizing sampling circuitry
BG109997A (bg) Метод за управление на синхронен електродвигател
JPH0254469B2 (de)
US5814983A (en) Method for sensing DC current and sensor for carrying out same

Legal Events

Date Code Title Description
PUAI Public reference made under article 153(3) epc to a published international application that has entered the european phase

Free format text: ORIGINAL CODE: 0009012

AK Designated contracting states

Kind code of ref document: A1

Designated state(s): DE FR GB IT

AX Request for extension of the european patent

Free format text: AL;LT;LV;MK;RO;SI

17P Request for examination filed

Effective date: 19990317

GRAG Despatch of communication of intention to grant

Free format text: ORIGINAL CODE: EPIDOS AGRA

17Q First examination report despatched

Effective date: 19990531

GRAG Despatch of communication of intention to grant

Free format text: ORIGINAL CODE: EPIDOS AGRA

GRAH Despatch of communication of intention to grant a patent

Free format text: ORIGINAL CODE: EPIDOS IGRA

AKX Designation fees paid

Free format text: DE FR GB IT

GRAH Despatch of communication of intention to grant a patent

Free format text: ORIGINAL CODE: EPIDOS IGRA

GRAA (expected) grant

Free format text: ORIGINAL CODE: 0009210

RAP1 Party data changed (applicant data changed or rights of an application transferred)

Owner name: LUCAS INDUSTRIES LIMITED

AK Designated contracting states

Kind code of ref document: B1

Designated state(s): DE FR GB IT

REF Corresponds to:

Ref document number: 69800081

Country of ref document: DE

Date of ref document: 20000330

ITF It: translation for a ep patent filed
ET Fr: translation filed
PLBE No opposition filed within time limit

Free format text: ORIGINAL CODE: 0009261

STAA Information on the status of an ep patent application or granted ep patent

Free format text: STATUS: NO OPPOSITION FILED WITHIN TIME LIMIT

26N No opposition filed
REG Reference to a national code

Ref country code: GB

Ref legal event code: IF02

REG Reference to a national code

Ref country code: GB

Ref legal event code: 732E

REG Reference to a national code

Ref country code: DE

Ref legal event code: R081

Ref document number: 69800081

Country of ref document: DE

Owner name: GOODRICH CONTROL SYSTEMS, SOLIHULL, GB

Free format text: FORMER OWNER: LUCAS INDUSTRIES LTD., LONDON, GB

Effective date: 20140128

Ref country code: DE

Ref legal event code: R081

Ref document number: 69800081

Country of ref document: DE

Owner name: GOODRICH CONTROL SYSTEMS, GB

Free format text: FORMER OWNER: LUCAS INDUSTRIES LTD., LONDON, GB

Effective date: 20140128

REG Reference to a national code

Ref country code: FR

Ref legal event code: TP

Owner name: GOODRICH CONTROL SYSTEMS

Effective date: 20140313

Ref country code: FR

Ref legal event code: CJ

Effective date: 20140313

Ref country code: FR

Ref legal event code: CD

Owner name: GOODRICH CONTROL SYSTEMS

Effective date: 20140313

Ref country code: FR

Ref legal event code: CA

Effective date: 20140313

REG Reference to a national code

Ref country code: FR

Ref legal event code: PLFP

Year of fee payment: 19

PGFP Annual fee paid to national office [announced via postgrant information from national office to epo]

Ref country code: GB

Payment date: 20160627

Year of fee payment: 19

PGFP Annual fee paid to national office [announced via postgrant information from national office to epo]

Ref country code: FR

Payment date: 20160622

Year of fee payment: 19

PGFP Annual fee paid to national office [announced via postgrant information from national office to epo]

Ref country code: IT

Payment date: 20160627

Year of fee payment: 19

Ref country code: DE

Payment date: 20160622

Year of fee payment: 19

REG Reference to a national code

Ref country code: DE

Ref legal event code: R119

Ref document number: 69800081

Country of ref document: DE

GBPC Gb: european patent ceased through non-payment of renewal fee

Effective date: 20170721

REG Reference to a national code

Ref country code: FR

Ref legal event code: ST

Effective date: 20180330

PG25 Lapsed in a contracting state [announced via postgrant information from national office to epo]

Ref country code: GB

Free format text: LAPSE BECAUSE OF NON-PAYMENT OF DUE FEES

Effective date: 20170721

Ref country code: DE

Free format text: LAPSE BECAUSE OF NON-PAYMENT OF DUE FEES

Effective date: 20180201

PG25 Lapsed in a contracting state [announced via postgrant information from national office to epo]

Ref country code: FR

Free format text: LAPSE BECAUSE OF NON-PAYMENT OF DUE FEES

Effective date: 20170731

PG25 Lapsed in a contracting state [announced via postgrant information from national office to epo]

Ref country code: IT

Free format text: LAPSE BECAUSE OF NON-PAYMENT OF DUE FEES

Effective date: 20170721