DE102005020673A1 - Monitoring and control system for operation and protection of DC motors used on automobile systems - Google Patents

Abstract

A monitoring and control unit (4) is connected to a DC motor (5) and consists of a power driver stage (3), regulator (2) and a microprocessor based input/output with memory (1). The memory provides set point parameters that are used in the monitoring function to check and control temperature, voltage and signal timing.

Description

The The invention relates to an evaluation and control electronics for direct current (Direct Current, DC) motors in particular with respect to the field of application Automotive technology.

• – Überlast durch Wicklungs- oder Lagerschaden
• – Kurzschluß durch Festsetzen der Welle, Wicklungs- oder Kollektorschaden
• – Umwelteinfluß wie Feuchte/Wasser und Temperatur
• – Äußerer Einfluß von Fremdkörpern.

In the automotive industry, electric drives are increasingly being used for a wide variety of functions, since they are easy to mount, switch, control, and monitor. The following are in particular the motor protection of fan / fan and pump motors, which are operated in the safe on / off or in the alternating load operation. Motor protection consists of monitoring the electrical parameters of the motor. It can be distinguished

• - Overload due to winding or bearing damage
• - Short circuit due to shaft lock, winding or collector damage
• - Environmental impact such as humidity / water and temperature
• - External influence of foreign bodies.

Of the Fan / fan motor can be blocked from the outside or the bearings are stuck by foreign body action; it threatens Burns. After removal of the blockade runs the Do not restart the engine.

At the Pump drive is also a blockade from the outside possible; the pump controls e.g. the Coolant circuit. Cause for reduced pump performance can increase the life of the drive, Pollution degree in the cooling circuit and, at collector motors, the wear of brushes or coals. Also Dry running of the pump is possible.

Engines are generally facing overload protected; most frequently Motor protection switches, motor protection relays or fuses are included for use.

Motor protection switch protect in case of overload, Non-start and / or failure of a conductor in the ladder system; she can as switching and protective devices be used. Motor protection switches i.a. thermal Bimetals as an actor. The time of thermal tripping, bimetallic tripping, is dependent from the current consumption of the motor to be protected; the thermal trigger reacts lazily, the electromagnetic release reacts quickly according to a given current-time characteristic. The bimetallic triggering is, because of too rapid warming of the Resistance wire to the combustion, not for the short-circuit protection suitable; the bimetal does not respond to the short circuit.

Motor protection switch with exclusively thermal overload trip, are Fuses for the Short circuit protection upstream, such as an electromagnetic tripping device for the short circuit. At a the adjustment range of the thermal overload release adapted current, the Release current, the electromagnetic release triggers immediately in the event of a short circuit.

The Voltage drop coil prevents an uncontrolled start of the engine on return the tension.

The thermal overcurrent relay i.a. set to the rated current of the motor to be protected; take over the short circuit case Fuses.

The Unlock button of the motor protection relay takes over the activation the control circuit of the contactor after the trip with following Contact closure.

With Temperature sensors inserted into the motor winding directly detect the winding temperature and provide full motor protection against impermissibly high winding temperatures to protect the winding insulation. The temperature detection may e.g. by at particularly critical points, such as windings or Bearings, mounted thermistors done.

in the Following is the state of the art based on intellectual property rights closer to the engine protection area considered.

In the patent CH 410 130 For example, a DC motor controller with electric switch is described mainly for traction vehicles.

Patent CH 401 219 describes a DC motor controller for traction vehicles with semiconductor switches.

In the European patent specification EP 633 844 B1 / DE 693 25 268 T2 / US 859 590 For example, the optimal construction of a DC motor control for traction is disclosed with an electronic control device for a series wound or a separately energized DC motor comprising only metal oxide semiconductor field effect transistors (MOSFET) devices for switching both the field and armature currents used by the engine. Electrical or mechanical requirements for contacts to the control should be eliminated. Effective, regenerative braking is also foreseen, even at low engine speeds. The controller has a full stop bridge bridge circuit for controlling the field current and a half-bridge circuit for controlling the armature current on.

Under the subject of engine monitoring, the patent discloses DD 255 028 A1 an artificial fault current during thermal motor monitoring. The invention finds application in thermal motors and in plant protection. The feature of the invention is that in a system, such as an electric submersible pump, a fault current after temperature increase by PTC thermistor, DIAC and TRIAC is generated, which brings the plant protecting residual current circuit breaker to trip.

In the patent EP 291 332 B1 / DE 38 80 732 T2 / AT 89 090 E For example, an electronic pump controller for a small pump driven by a DC motor is provided wherein the operation of the pump and thus the flow rate of fluid delivered by the pump is controlled by a voltage applied to the pump. It is important to deliver a volume of fluid that can be accurately measured and controlled. The pump is supplied with a defined input signal which can be varied according to the specific operating conditions and exactly complies with its set value.

Fan controllers are described in the patent applications DD 231 671 A1 as energy saving fan control and in DE 44 37 796 A1 as a temperature-dependent pressure control, in particular for fan control disclosed.

essential feature The first invention is that while maintaining the usability the thermal time constant of the unit to be ventilated, the fan is not alone in dependence from the temperature of the aggregate, but also already below the temperature over a power-on threshold is turned on and off.

The second application discloses a multi-size dependent pressure control in which starting from a feed pressure, an output pressure dependent on a measured quantity is generated, with which in particular the cooling capacity of the cooling device an internal combustion engine is affected, that the output pressure over a Cascade pressure control is generated and that on the thus regulated output pressure Actuating means actuated be that the cooling power the cooling device influence.

Another way of watching the motor is the state observer realized as hardware and / or software DD 224 695 A1 the process stabilization in the event of functional failure deployed state observer.

In the European patent application EP 1 158 658 A2 A "Control device and method for a wide speed range induction machine based upon flux estimation performed by means of a Luenberg state observer" is presented and described.

The European patent application EP 1 129 944 A1 discloses the state variables of a moving body (docking, rendez-vous) with three retroreflectors and state observers (Luenberger). The invention relates to a method for Be mood of the state variables of a moving rigid body in space, in particular for determining the position and position of a spaceship in a approach or docking maneuver. Another related application relates to robotics.

None the solutions presented meets the demands of the task, a simple but safe, ongoing monitoring the electrical parameter of used in automotive engineering DC motors. about Resistor combinations that represent resistance fuses, be warming up Relay for switching off and thus the fan / fan and pump functions set. Both the air and the water cooling of the Internal combustion engine fail; unforeseeable consequential damage can occur. An emergency running feature of the aggregates, such as operation with reduced Performance is not provided.

applications in the automotive industry group-secured by means of carrier fuses; cables with big Cross sections provide for a short circuit proof Wiring.

Of the The invention is therefore based on the object, a simple, but safe, continuous monitoring the electrical parameter of used in automotive engineering To develop DC motors and the 'static' on / off circuit of the engine, such as Temperature control over Resistors and Switching relay, protection via Temperature fuse or the temperature-dependent fuse to replace.

These Task is inventively characterized solved, that the Detection and regulation of electrical, mechanical and thermal Parameters over an evaluation and control electronics are running continuously and dynamically.

The achievable with the present invention consist in particular that instead of a static On / off switching of the DC motors, such as temperature control via bimetallic relay to realize a permanent monitoring of the electrical, mechanical and thermal parameters by means of an evaluation and control electronics.

The 'hard' switch-off torque behavior the z.Zt. installed, static on / off switching of the DC motors leads to large inductance power losses, the above the wiring system wiring can be compensated.

Further Advantages of the invention are a simpler handling of the semiconductor control, a parametrizable presetting of the control as well as the programmability and storage capability of Evaluation and control electronics with the result of a controlled Slope. The control of the slope in dependence the engine power dependent overshoot thanks to the feedback loop Motor / evaluation and control electronics.

The further description of structure and, if necessary, the mode of action the evaluation and control electronics for DC drives as an embodiment The invention is made with the assistance of drawings that described in more detail below become. Show it

1 the logical structure of the evaluation and control electronics for DC drives

2 exemplifies the construction of a refrigeration cycle management in the automotive sector.

According to a further embodiment of the invention, 1 , there is the evaluation and control electronics 4 from the power electronics module 3 , the loop component 2 and the memory and input / output device with microprocessor 1 , The output of the power electronics 3 is set via the R regulator preset to the input of the control loop 2 fed back and delivers the data of the actual state of the motor to the controller block. The memory and input / output device 1 supplies the setting parameters for the controller 2 , has a bus interface I / O and offers the possibility of manual data entry. In addition, in the memory and input / output device 1 the motor characteristic is stored.

• – Spannungsregelung und -überwachung
• – Signal- und Zeitüberwachung
• – RC-Oszillator mit Ladungspumpe zur Leistungsregelung
• – Externe Leistungsregelung mit Schutzfunktion
• – Motorstrom-Messung und Überstrom-Erkennung mit Schutzmaßnahme
• – Interne und externe Temperatur-Überwachung
• – Sleep-Modus mit Wake-up-Funktion
• – Fehlerfunktions-Generator mit Signalausgang
• – Analoger Multiplex-Schalter
• – Signal-Prozessor-Interface und -Register.

Another embodiment of the inventive novelty is given by the following functionality

• - Voltage regulation and monitoring
• - Signal and time monitoring
• - RC oscillator with charge pump for power control
• - External power control with protective function
• - Motor current measurement and overcurrent detection with protective measures
• - Internal and external temperature monitoring
• - Sleep mode with wake-up function
• - Fault generator with signal output
• - Analog multiplex switch
• - Signal processor interface and registers.

• – Gleichstrommotor ohne Stromversorgung
• – Drahtbrucherkennung beim Leistungsschalter oder Motor
• – Kurzschluß beim Leistungsschalter
• – Erkennung und Schutz bei blockiertem Motor
• – Kurzschlußerkennung und -schutz im Motorbereich
• – Interne und externe Übertemperatur-Erkennung und -Schutz
• – Batterieüberwachung mit Über- und Unterspannungsschutz
• – Schutz der Leistungselektronik bei Generatorbetrieb.

Another embodiment of the invention provides microprocessor programmable fault function processing having the following characteristics

• - DC motor without power supply
• - Wire break detection at the circuit breaker or motor
• - Short circuit at the circuit breaker
• - Detection and protection with blocked engine
• - Short circuit detection and protection in the motor area
• - Internal and external overtemperature detection and protection
• - Battery monitoring with overvoltage and undervoltage protection
• - Protection of the power electronics during generator operation.

The sum of the advantages of the control and evaluation electronics 4 for DC motors is in programmable pulse width modulation, in the permanent regulation of motor current, voltage and speed, the permanent monitoring and the constant protection of the units. While the control circuit hardware has internal and external standard interfaces and connections, the motor control is software-controlled with the aid of motor-specific parameters in the microprocessor.

A further advantageous embodiment of the invention is in accordance with the application of a refrigeration cycle management from the automotive sector 2 given. Here, the inventive novelty evaluation and control electronics 4 ever applied to the cooling circuits air cooling and water cooling 5 in the automobile. As described above, the two cooling circuits are controlled locally and globally by a refrigeration cycle condition observer 6 permanently monitored in the form of a cooling water balance I / O. From the 'static' on / off circuit of motor fan and pump with the disadvantages mentioned above, has become a dynamic control circuit, which has controllable emergency running characteristics even with reduced load.

The numerous possibilities and advantages of the embodiment of the invention are reflected in the number the property rights claims contrary.

1

Storage- and input / output module

2

Loop module

3

Power electronics module

4

evaluation and control electronics

5

DC motor

6

Cooling circuit-state observer

I / O

Input / Output

M

Motor / drive

R

regulators default

Claims (12)

The invention relates to an evaluation and control electronics ( 4 ) for direct current (DC) motors ( 5 ) in particular with regard to the field of application automotive technology, characterized in that the detection and control of the electrical, mechanical and thermal parameters by an evaluation and control electronics ( 4 ) is ongoing and dynamic. Evaluation and control electronics according to claim 1, characterized in that the electronics ( 4 ) from the power electronics module ( 3 ), the control circuit module ( 2 ) and the memory and input / output module with microprocessor ( 1 ) consists. Evaluation and control electronics according to at least one of claims 1 and 2, characterized in that the output of the power electronics ( 3 ) via the controller default setting R to the input of the control loop 2 is fed back and supplies the data of the actual state of the motor to the control circuit block. Evaluation and control electronics according to at least one of claims 1 to 3, characterized in that the memory and input / output module ( 1 ) the setting parameters for the controller ( 2 ), has a bus interface I / O, offers the possibility of manual data entry and, moreover, in the memory and input / output module ( 1 ) the motor characteristic is stored. Evaluation and control electronics according to at least one of claims 1 to 4, characterized in that the electronics ( 4 ) has voltage regulation and monitoring as well as signal and time monitoring. Evaluation and control electronics according to at least one of claims 1 to 5, characterized in that the electronics ( 4 ) has an RC oscillator with charge pump for power control and has an external power control with protection. Evaluation and control electronics according to at least one of claims 1 to 6, characterized in that the electronics ( 4 ) performs a motor current measurement, has an overcurrent detection and initiates protective measures in the event of a fault. Evaluation and control electronics according to at least one of claims 1 to 7, characterized in that the electronics ( 4 ) enables an internal and external temperature monitoring, has a sleep mode with wake-up function and emits signals in the event of an error by means of an error function generator. Evaluation and control electronics according to at least one of claims 1 to 8, characterized in that the electronics ( 4 ) has an analog multiplex switch and has a signal processor interface and register. Evaluation and control electronics according to at least one of claims 1 to 9, characterized in that by means of the microprocessor of the memory and input / output module ( 1 ) a programmable fault function processing takes place, with the characteristics - DC motor without power supply - wire break detection at the circuit breaker or motor - short circuit at the circuit breaker - detection and protection when motor blocked - short circuit detection and protection in the motor area - internal and external overtemperature detection and protection - Battery monitoring with overvoltage and undervoltage protection - Protection of power electronics during generator operation. Evaluation and control electronics according to at least one of claims 1 to 10, characterized in that by means of a respective locally controlling electronics ( 4 ) for the air and water cooling circuit ( 5 ) a globally controlling refrigeration cycle management with refrigeration cycle condition observers ( 6 ) arises. Evaluation and control electronics according to at least one of claims 1 to 11, characterized in that the locally controlling electronics ( 4 ) in addition to the switching and control mode has controllable emergency running properties with reduced load.