METHOD FOR PROTECTION OF AN ENERGY STORAGE SOURCE, AND IN PARTICULAR A MOTOR VEHICLE BATTERY

• US 20100053825A1
• Filed: 07/17/2009
• Published: 03/04/2010
• Est. Priority Date: 08/26/2008
• Status: Active Grant

• Current Assignee: Valeo Equipements Electriques Moteur (Valeo SE)
• Original Assignee: Valeo Equipements Electriques Moteur (Valeo SE)
• Inventors: Chassard, Pierre, Gendron, Vincent, Tisserand, Pierre
• Granted Patent: US 8,164,867 B2
• Time in Patent Office: Days
• US Class Current: 361/21
• CPC Class Codes: H02J 7/163 with special means for initiating or limiting the excitation current
• CPC Class Codes: Y02T 10/70 Energy storage systems for electromobility, e.g. batteries

Abstract

A method for protection of an energy storage source (2), in particular a battery of a motor vehicle, against possible overloading caused by prolonged application of an electric voltage to the energy storage source, this voltage being generated at least partially by a rotary electric machine (1) such as an alternator or an alternator-starter, the method comprising the following steps:

• • permitting measurement of a charge level of the energy storage source, this charge level being represented for example by a voltage measured at the terminals of the energy storage source or a PWM signal, whilst the rotary electric machine is functioning in a predetermined functioning mode, and electric excitation is being applied to it;
  • comparing a value (SENSE) of this measurement with a reference value (Max_SP);
  • if the value measured for the energy storage source is greater than the reference value, interrupting the excitation applied to the rotary electric machine.

Claims

1. Method for protection of an energy storage source (2), adapted to for use as a battery of a motor vehicle, against possible overloading caused by prolonged application of an electric voltage to the energy storage source, this voltage being generated at least partially by a rotary electric machine (1) adapted for use as an alternator or an alternator-starter, the method comprising the following steps:

permitting measurement of a charge level of the energy storage source, said charge level being represented for example by a voltage measured at the terminals of the energy storage source or a PWM signal, while the rotary electric machine is functioning in a predetermined functioning mode, and electric excitation is being applied to said electric machine;

comparing a value (SENSE) of said measurement with a reference value (Max_SP), this reference value (Max_SP) being selected as the larger out of two command values (REF_INT;

REF_EXT);

if the value measured for the energy storage source is greater than the reference value, interrupting the excitation applied to the rotary electric machine.

2. Method according to claim 1, wherein during said predetermined functioning mode, the excitation which is applied to the rotary electric machine (1) is substantially constant.

3. Method according to claim 2, wherein the predetermined functioning mode corresponds to a pre-excitation mode (PRE_EXC) of the rotary electric machine.

4. Method according to claim 1, wherein the excitation which is applied to the rotary electric machine during said functioning mode corresponds to a cyclical ratio which is selected from between 5% and 20%, and in particular is close to 12.5%.

5. Method according to claim 1, wherein the electrical excitation which is applied to the rotary electric machine is supplied by a regulator, and wherein the first one (REF_EXT) of the two command values is supplied externally to the regulator, in particular by a system to control the vehicle engine, and is transmitted to this regulator, and the second one (REF_INT) of these command values is generated internally by the regulator.

6. Regulator for a rotary electric machine such as an alternator or an alternator-starter, this regulator comprising:

a logic block (30) which is adapted to receive at least one item of information which is representative of a charge level of an energy storage source, a reference value and an item of information which is representative of a functioning mode of the rotary electric machine which is selected from amongst a plurality of functioning modes, and is designed to make possible a comparison of the information which is representative of a charge level of the energy storage source, with the reference value, at least when the rotary electric machine is functioning in a predetermined mode detected by the logic block;

a maximum command detection block (31), in particular of the digital type, which is designed to generate said reference value selected as the maximum of an internal command and an external command detected by this detection block;

a field controller (15) which is designed to receive an order from the logic block in order to give rise to interruption of excitation applied to the rotary electric machine, when, further to said comparison, the logic block (30) detects an excessive charge level of the energy storage source during this functioning mode.

7. Regulator according to claim 6, further comprising means to receive and process at least one item of information which is representative of the speed of rotation of the rotor of the rotary electric machine.

8. Regulator according to claim 6, further comprising means to impose on the rotary electric machine, from amongst a plurality of functioning modes, a pre-excitation functioning mode, during which electrical excitation, corresponding to a predetermined cyclical ratio, which in particular is maintained constant during this functioning mode, and for example is substantially equal to 12.5%, is applied to the rotary electric machine.

9. Regulator according to claim 8, further comprising means such as, in non-defective functioning, to permit the receipt of the information which is representative of the speed of rotation of the rotor of the rotary electric machine, during the pre-excitation functioning mode of the rotary electric machine.