MXPA00005271A - Method and apparatus for automotive and other battery testing - Google Patents

Abstract

The invention relates to a method and apparatus for automotive and other battery testing. Particularly, but not exclusively, the invention relates to such method and apparatus applicable to the roadside testing of automotive vehicles'batteries, and the corresponding testing of such vehicles'batteries in diagnostic and service-oriented functions.

Description

METHOD AND APPARATUS FOR BATTERY TESTING AUTOMOTIVE AND OTHER This invention relates to a method and apparatus for testing automotive batteries and others. Particularly, although not exclusively, the invention relates to said method and apparatus applicable to the road test of automotive vehicle batteries and the corresponding test of these vehicle batteries in diagnostic and service-oriented functions. A particular practical application of the embodiments of the invention is found in providing a method and apparatus of particular utility to patrol personnel who offer assistance on the road to users of automotive vehicles. The invention will probably find utility in related non-automotive applications. A particular practical problem in the field of fault diagnosis in automotive vehicles lies in providing a practical and simple means with which common failures in relation to basic automotive systems can easily be identified. Of course, computer based total vehicle analysis systems are available for analysis purposes, and these are effective. However, these systems are usually dedicated to a specific vehicle model and thus are applicable only to that extremely narrow range of vehicles, and in any case they are not suitable for road use. Another problem that arises relates to the fact that many faults are intermittent in nature and in general can not be tracked using conventional conventional equipment until the failure has become so noticeable that it is present at all times. An additional requirement is that methods and apparatuses of this type require to be easily used by patrol personnel on the road under adverse weather conditions, and under similarly adverse conditions regarding the maintenance status of the vehicle as far as testing is concerned, and in consideration of the fact that many modern vehicles are built to be highly resistant to rain, snow, and automotive lubrication and other fluids, making it relatively difficult to gain access to at least some of the vehicle operating systems, notably starting system and related electrical components. In certain embodiments of the invention, a hand-held portable equipment is provided in size to hold it comfortably by hand and for operation and control (with the user's thumb) using simple procedures and relatively few buttons with a display case. line (for example) or light-emitting diodes as a user interface. Also in this embodiment of the invention, access for electrical contact to electrical parts, can be simplified by the use of clamp connectors to battery terminals using a Kelvin connection to remove the effect of degradation of dirty contacts. A device for temperature detection can also be incorporated. These system options improve measurement and diagnostic accuracy. These modalities reduce the dexterity and time requirements imposed on the user. Thus, one aspect of the invention relates mainly to systems for testing that involve the use of hand-held portable equipment, although certain aspects of the technical advance provided by the modalities have utility in relation to equipment that is not portable manual and of conformity is claimed. Generally viewing the state of the art in relation to battery tests, previous proposals that include our manual portable battery test system (reference P53488WO) as described in PCT / GB98 / 01634, currently unpublished, and which describes these battery test systems, at least one of which includes the use of charging stages and / or testing of transient battery charging conditions. Another previous proposal, which in this case is published, is established in EP 0756167A (reference P52740EP) that describes the use of neural networks in relation to the analysis of transient battery test loads. Previously proposed battery test systems have been able to produce useful data, but it is considered that more valuable data may be available by the use of a modified test technique, and this data may be available equally convenient as in portable equipment systems manual, by the use of portable hand-held devices and may be able to provide data that represents a more realistic assessment of performance characteristics in current battery use, and yet which are capable of being delivered in a cost effective manner. According to the invention, a method and apparatus applicable to the routine test of batteries for automotive vehicles and similar batteries is provided as defined in the accompanying claims. In one embodiment of the invention, the convenience of use is ensured by the use of a hand-held portable equipment system, access to test data representing a realistic assessment of the current performance capability of the battery is provided by causing the battery to supply a current representing (if not the current current supply) at least a realistic approximation, and the cost effectiveness is achieved and made available by the use of a test circuit where realistic battery currents are generated for an interval of transient time such that despite the use of a hand-held portable equipment, the heat generated is relatively low and can be adjusted within cost effective component systems. In this way, the embodiment of the invention provides a convenient, effective and cost-effective battery test system that is capable of simulating current battery operating conditions and thus obtaining a measure of battery performance in relation to the battery. same without the need for substantial thermal collector arrangements or other complexities, which have limited the usefulness of previously proposed systems. In the described embodiment, a control circuit that is part of the hand-held portable test equipment is adapted to connect a test electric load to a battery to be tested. Analysis means are adapted to analyze the. Voltage profile produced, or analyze related aspects of the reaction of the battery to the load. The modality is characterized by the aspect because the charge is caused, at least for batteries in good condition, to affect the production by the battery of a macro current, which is comparable to currents that arise in use of the battery, and the charge is connects to the battery by a transient time interval that is in the range of up to 100 milliseconds, for example 10 to 30 milliseconds, with which the heat generated by the transient macro current, in this way can be accepted by the device portable manual. The use in the modality of a transient macro current allows the production of corresponding tests, in a reasonably realistic way that would be obtained in current test battery use, but without the accompanying heat and other related difficulties that have so far This approach has been ruled out in manual portable equipment type test apparatus. Also in the embodiment, the control circuit produces the predetermined and required level of current flow through a closed-loop re-feeding circuit that effectively serves to demand the pre-determined level of test current that the system considers applicable in a true case. In the mode, the current level is determined by the system according to the open circuit voltage available from the battery and in practice, the mode uses four levels of open circuit voltage to determine four corresponding levels of battery current that are in the region of 100 to 120 amps, 47 to 55 amps, 18 to 25 amps and 12 to 17 amps. By the use of a closed-loop current control circuit, in the embodiment, the advantage (for production purposes) of effectively controlling the tolerances of circuit components (particularly in field effect transistors [FETs]) is provided. ), which would otherwise lead to unacceptable variations (within a production lot) in the resistive load applied to the battery. To put in context the current amperage figures cited above in relation to the hand-held portable test equipment of the present modalities, it is necessary to keep in mind that previously known equipment of this type has employed manual portable equipment power in the order of 2 amps. Another characteristic of the described modality refers to its use of a twin pulse test technique where the second pulse (supplied by the battery to the load) that is used for test purposes, the first pulse is a preliminary pulse that ( it has been found) results in improved test performance when effectively conditioning the battery.

In relation to the time interval during which the transient load is applied to the battery, the modalities use, in some cases, a main transistory load / current pulse that falls within the time intervals defined here discussed, and followed by a relatively large current deterioration period, which is at least as long and sometimes variable is longer than the transient load interval. In the embodiments described, the transient load switching function is performed by a digitally controlled circuit using field effect transistors, but the same or comparable load connection ranges can be effected by analog circuits and the accompanying claims are intended to cover both systems of conformity. Alternating circuits for applying a transient current load according to the invention include pulse-width-modulation (PWM) techniques that allow current charge pulse shaping by varying the space / PWM ratio. By using PWM in a H-bridge circuit configuration that incorporates some form of temporary energy storage, a large proportion of the energy used in battery testing can be returned to the power supply, thereby significantly reducing energy dissipation in the manual portable equipment. Now embodiments of the invention will be described by way of example with reference to the accompanying drawings in which: Figures 1 and 2 of the accompanying drawings show respectively in block / flow diagram format, the presentation of the prior art and a modality of the present invention. In the embodiment of Figure 2 (and its prior art corresponding to Figure 1) in the representation of the prior art shown in Figure 1, a battery 100 is connected by a switching circuit 102 to a load 104 which is part of the total test apparatus 106 and the generated heat is absorbed by a thermal collector 108 in accordance. The voltage profile analysis is provided by the circuit 110 which determines the category of the battery 100 by reference to known voltage data profiles established in a corresponding database. In the embodiment of Figure 2, a hand-held portable equipment 120 is connected through a closed-loop current control circuit 122 with a battery 124 for application of a transient load 126 by the switching circuit 128 to generate (approximation or approach a) the normal working battery current as indicated at 130. The switching circuit connects the load 126 by typically about 20 milliseconds and the circuit 122 is configured to draw a current in the order of 100 amps from the battery 124. The voltage profile produced is analyzed according to the circuit 132 in accordance with the description in our previous EP specification identified above, all the technical content of which is incorporated herein for purposes of description.

Claims (14)

1. CLAIMS 1.- A test method applicable to the routine test of batteries for automotive vehicles and similar batteries, the method is characterized in that it comprises: (a) providing a battery to be tested; (b) provide a test electric load for connection to the battery; (c) providing a control circuit adapted to connect the load to the battery for an interval of less than one second; and (d) again providing adapted analysis means for analyzing the voltage profile or related aspects of the reaction of the battery to the load; characterized by: (e) causing the charge to cause the battery, at least for batteries in good condition, to supply a macro current that is comparable to currents arising in use of the battery; (f) causing the control circuit to connect the load to the battery for a transient time interval that is in the range of up to 100 milliseconds; and (g) providing the control circuit as part of the portable hand-held device adapted to be operated and connected to the battery in the form of a hand-held portable test equipment, and the transient macro current generates a quantity of heat relative to the hand-held portable equipment. which can be accepted by the device of manual portable type.
2. 2. - A test method applicable to the routine test of batteries for automotive vehicles and other batteries, the method comprises causing a battery to be tested to supply a macro current that is comparable with currents that arise in use of the battery, to a test load for a transient time interval that is in the range of up to 200 milliseconds.
3. 3. - A test method according to any of claims 1 or 2, characterized by causing the control circuit to produce a predetermined level of current flow by means of a closed-loop re-feeding circuit.
4. 4. - A test method according to claim 3, characterized in that the control circuit determines the level of current flow by reference to the open circuit voltage of the battery.
5. 5. - A test method according to claim 4, characterized by causing the control circuit to determine the current flow level by selecting one of two or more voltage levels or ranges by reference to the open circuit voltage of Battery.
6. 6. - A test method according to any of claims 1 to 5, characterized by causing the control circuit to connect the load to the battery for the transient time interval as far as the peak current flow is concerned, followed by a period of current deterioration from 0 to as large as the transient time interval.
7. 7. Apparatus applicable for the routine testing of batteries for automotive vehicles and similar batteries, the apparatus comprises: (a) connection means for the apparatus with a battery to be tested; (b) a test electric load to connect the battery to be tested; (c) a control circuit adapted to connect the load to the battery for an interval of not less than one second; and (d) analysis means adapted to analyze the voltage profile or related aspects of the reaction of the battery to the load; characterized by: (e) the control circuit is adapted to cause the battery to supply a macro current that is comparable with currents arising in use of the battery; (f) the control circuit is also adapted to connect the battery to the load for a transient time interval that is in the range of up to 100 milliseconds; and (g) the control circuit is part of the portable hand-held device adapted to be operated and connected to the battery in the form of a portable hand-held test equipment, and the transient macro current generates a quantity of heat in use and in relation to the equipment portable manual that can be accepted by the handheld portable equipment.
8. 8.- Apparatus applicable to the routine test of batteries for automotive vehicles and other batteries, the apparatus is characterized by a control circuit adapted to cause the battery to supply a macro current that is comparable with currents that arise in use of the battery, to a load for a transient time interval that is in the range of up to 200 milliseconds.
9. 9. - Apparatus in accordance with the claim 7 or 8, characterized in that the control circuit comprises a closed-loop re-feeding circuit adapted to produce a given level of current flow of the battery.
10. 10. Apparatus in accordance with the claim 8, characterized in that the control circuit is adapted to determine the level of current flow from the battery by reference to the open circuit voltage of the battery.
11. 11. Apparatus according to claim 10, characterized in that the control circuit is adapted to determine the level of current flow from the battery by selecting one of two or more levels or current flow ranges by reference to the circuit voltage. open the battery.
12. 12. Apparatus according to any of claims 7 to 10, characterized in that the control circuit is adapted to connect the battery to the load for a transient time interval followed by a period of current deterioration from 0 to as large as the transient time interval.
13. 13. - Method applicable to the routine test of batteries for automotive vehicles and similar batteries, the method is substantially as described herein with reference to the accompanying drawings.
14. 14. Apparatus applicable to the routine test of batteries for automotive vehicles and similar batteries, the apparatus is substantially as described herein with reference to the accompanying drawings.