Classifications

• • H—ELECTRICITY
  • H02—GENERATION; CONVERSION OR DISTRIBUTION OF ELECTRIC POWER
  • H02H—EMERGENCY PROTECTIVE CIRCUIT ARRANGEMENTS
  • H02H7/00—Emergency protective circuit arrangements specially adapted for specific types of electric machines or apparatus or for sectionalised protection of cable or line systems, and effecting automatic switching in the event of an undesired change from normal working conditions
  • H02H7/08—Emergency protective circuit arrangements specially adapted for specific types of electric machines or apparatus or for sectionalised protection of cable or line systems, and effecting automatic switching in the event of an undesired change from normal working conditions for dynamo-electric motors
  • H02H7/085—Emergency protective circuit arrangements specially adapted for specific types of electric machines or apparatus or for sectionalised protection of cable or line systems, and effecting automatic switching in the event of an undesired change from normal working conditions for dynamo-electric motors against excessive load
  • H02H7/0852—Emergency protective circuit arrangements specially adapted for specific types of electric machines or apparatus or for sectionalised protection of cable or line systems, and effecting automatic switching in the event of an undesired change from normal working conditions for dynamo-electric motors against excessive load directly responsive to abnormal temperature by using a temperature sensor

Definitions

• the present invention relates to a block integrating a direct current electric motor and an electronics for controlling said motor.
• An object of the invention is to further improve the protection against thermal increases locked rotor of an electric motor block incorporating control electronics
• the invention provides a block of direct current electric motor comprising a connection plate and a card which carries electronics for controlling said motor, said card comprising current monitoring means for detecting the locking of the rotor of said motor, characterized in that said card and / or said plate carry means forming temperature sensor (s) and in that said card also comprises means which control the supply of the motor and which are connected to said sensor means ( s) of temperature, as well as to the current monitoring means, said control means cutting off the power to the motor when the locking of the motor rotor is detected and a temperature measured by the sensor means reaches a higher threshold value and restoring power to the motor when said temperature has at least fallen to a lower threshold value
• FIG. 1 is a graph on which we have focused as a function of time on the one hand the intensity of the supply current in said motor in accordance with a known sequence making it possible to protect an electric motor block incorporating control electronics when a blockage of the motor rotor is detected, and d 'other hand the evolution of the temperature of the engine block during this supply sequence
• - Figure 2 is a graph similar to that of Figure 1 which illustrates a supply sequence with protection means of the type of those proposed by the invention
• FIG. 3 is a schematic representation of an electric motor block with integrated control electronics according to a possible embodiment of the invention.
• FIG. 4 is a block diagram illustrating the assembly incorporating protection means of the type of those proposed by the invention.
• the protection proposed by the invention consists, when the rotor lock is detected, to cut the power to the motor when the temperature reaches a given threshold value T1 and to restore the power only when this temperature has dropped to a given threshold value T2.
• the engine block comprises at least two temperature sensors, one on the electronic card, the other on the plate which carries the brushes.
• the power supply to the electric motor is cut off when the temperature measured on the board reaches a value T P 1, or when the temperature measured on the electronic board reaches a value Tel.
• the motor is then again supplied with power only when the temperature measured on the circuit board has at least dropped to a value Tp2 or lower, while the temperature measured on the electronic card has at least dropped to a value T c 2.
• the cut-off temperature T P 1 is of the order of 200 ° C, while the cut-off temperature Tel is of the order of 130 ° C; the temperature T P 2 is of the order of 160 ° C., while the temperature T c 2 is of the order of 120 ° C.
• FIGS. 3 and 4 An example of possible arrangement for the elements of the engine block is for example illustrated in FIGS. 3 and 4.
• the carcass of the electric motor has been referenced by 1, its axis of rotation by 2
• connection-carrying plate 3 As can be seen more particularly in FIG. 4, this plate 3 itself carries on the one hand the brushes b of the motor and on the other hand tracks for connection to ground (carcass or radiators) or to battery voltage
• It also carries a printed circuit card 4 on which are installed various circuits involved in the supply of the electric motor.
• These different circuits consist for example of a circuit 5 for controlling the supply voltage supplied to the motor so as to maintain the speed of rotation at a set value C, of a driving circuit 6 which is controlled by the servo circuit 5, chopper and sawtooth generation circuits 7 and 8, means 9 for generating the voltages used by these different circuits from the battery voltage + bat, means 10 forming the capacity of decoupling
• These circuits also include a temperature monitoring circuit 12 and a current monitoring circuit 13, both connected to a diagnostic circuit 14
• the temperature monitoring circuit 12 includes, for example, a CTN resistor 15 which is mounted on the electronic card 4, as well as means with a bridge (s) and a comparator (s) for comparing the resistive value. of this CTN resistance at given thresholds
• This circuit 12 further comprises resistive means which are connected to a CTN resistor 16 which is mounted on the plate 3 and with which these means define one or more bridges, for, with means forming differential comparators, compare the resistive value of this resistor CTN at given thresholds the sensor means that constitutes the resistor 16 are advantageously arranged in the vicinity of a shunt, a coil or coals
• the current monitoring circuit 13 also includes a comparator assembly making it possible to compare the value of the voltage across a "shunt" 17 on the motor supply circuit with a given threshold.
• the signals at the output of these different comparators are processed by the diagnostic circuit 14, which comprises on the one hand a power transistor of the MOSFET type which controls the supply of the electric motor, and on the other hand means for controlling this transistor as a function in particular of the signals at the output of the various Comparators In particular, when the rotor locks, the "shunt" 17 and the circuits
• the plate 3 also includes means 18 for filtering the voltage + battery supply bat
• the electric motor block which has just been described advantageously finds application in the case of an electric motor for heating, ventilating or air conditioning a motor vehicle.
• the means 15, 16 forming the temperature sensor can be of the bimetallic strip type.

Landscapes

• Control Of Direct Current Motors (AREA)
• Protection Of Generators And Motors (AREA)
• Air-Conditioning For Vehicles (AREA)
• Stopping Of Electric Motors (AREA)
• Control Of Electric Motors In General (AREA)
• Electric Propulsion And Braking For Vehicles (AREA)

Applications Claiming Priority (3)

Publications (1)

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ID=9524032

Family Applications (1)

Country Status (9)

Families Citing this family (6)

Family Cites Families (9)

• 1998
  • 1998-03-13 FR FR9803128A patent/FR2776136B1/fr not_active Expired - Fee Related
• 1999
  • 1999-03-12 AU AU28400/99A patent/AU2840099A/en not_active Abandoned
  • 1999-03-12 WO PCT/FR1999/000555 patent/WO1999048183A1/fr not_active Application Discontinuation
  • 1999-03-12 BR BR9908734-0A patent/BR9908734A/pt not_active IP Right Cessation
  • 1999-03-12 JP JP2000537289A patent/JP2002507877A/ja active Pending
  • 1999-03-12 CN CNB998036978A patent/CN1252891C/zh not_active Expired - Fee Related
  • 1999-03-12 EP EP99909004A patent/EP1062715A1/de not_active Withdrawn
  • 1999-03-12 US US09/646,260 patent/US6459181B1/en not_active Expired - Fee Related
  • 1999-03-15 AR ARP990101119A patent/AR015542A1/es active IP Right Grant

Non-Patent Citations (1)

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