Inductive load control

Patent metadata

Field	Value
Publication number	US-10867734-B2
Application number	US-201715785715-A
Country	US
Kind code	B2
Filing date	Oct 17, 2017
Priority date	Oct 19, 2016
Publication date	Dec 15, 2020
Grant date	Dec 15, 2020

Abstract

A plurality of inductive loads (105) are connectable in parallel with one another between first and second terminals (120, 125), to which a controllable voltage (205) is applied. A method (300, 400) for operating the loads (105) includes the steps of detecting (305, 405) the connection of a previously non-energized load (105) between the terminals (120, 125); setting (310, 410, 435) the voltage (205) to a predetermined first value (210), and, after the lapse of a predetermined time interval (315, 415), adjusting the voltage (205) to a predetermined second value (215), with the second value (215) being lower than the first value (210).

First claim

The invention claimed is:

1. A method of operating a plurality of inductive loads, which can be connected parallel to one another between first and second terminals, to which a controllable voltage is applied, the method comprising:
detecting a connection of a previously non-energized load to the terminals;
setting the voltage to a predetermined first value;
adjusting the voltage, after lapse of a first predetermined time interval, to a predetermined second value, with the second value being lower than the first value; and
determining one of the first and the second values on a basis of an electrical resistance between the terminals.

2. The method according to claim 1 , further comprising adjusting the voltage, after a further predetermined time interval, to a predetermined third value with the third value being lower than the second value.

3. The method according to claim 1 , further comprising, in relation to a plurality of loads switched on at intervals, always setting the voltage to a highest of the first and the second values.

4. The method according to claim 2 , further comprising, if no load is connected to the terminals, reducing the voltage to a fourth predetermined value which is lower than the third predetermined value.

5. The method according to claim 1 , further comprising determining the electrical resistance on a basis of the voltage applied at the terminals and a current flowing through the terminals.

6. A method of operating an inductive load which can be connected between first and second terminals to which a controllable voltage is applied; the method comprising:
detecting a connection of a previously non-energized load to the terminals;
setting the voltage to a predetermined first value;
adjusting the voltage, after lapse of a first predetermined time interval, to a predetermined second value, with the second value being lower than the first value;
adjusting the voltage, after a further predetermined time interval, to a third value, with the third value being lower than the second value; and
determining one of the first and the second values on a basis of an electrical resistance between the terminals.

7. A device for operation of a plurality of switchable inductive loads between first and second terminals, the device comprising:
a half-bridge for applying a predetermined voltage between the terminals;
a control device being designed for controlling the half-bridge such that a predetermined voltage is applied between the terminals;
the loads being connectable in parallel with one another between the first and the second terminals; and
the control device being designed to set the voltage between the terminals to a predetermined first value, when a previously non-energized load is connected between the terminals, and, after lapse of a predetermined time interval, to reduce the voltage to a predetermined second value which is lower than the first value.

8. The device according to claim 7 , wherein the control device is also designed to reduce the voltage between the terminals, after the lapse of a further predetermined time interval, from the second value to a third value in which the third value is lower than the second value.

9. The device according to claim 7 , wherein the half-bridge comprises a first current control valve for connecting the first terminalto a high potential of an intermediate circuit voltage and a second current control valve for connecting the first terminal to a low potential of the intermediate circuit voltage ( 135 ), and the control device is designed to actuate the first and the second current control valves by turns in order to set the predetermined voltage.

10. A device for operating a switchable inductive load between first and second terminals, the device comprising:
a half-bridge for applying a predetermined voltage between the terminals;
a control device designed for actuating the half-bridge in such manner that a predetermined voltage is set between the terminals; and
the control device is designed to set the voltage between the terminals to a predetermined first value, when a previously non-energized load is connected between the terminals, and, after lapse of a predetermined time interval, to reduce the voltage to a predetermined second value which is lower than the first value, and, after lapse of a further predetermined time interval, to reduce the voltage from the second value to a third value in which the third value is lower than the second value.

Assignees

• Zahnradfabrik Friedrichshafen

Inventors

• Weinl Florian
• Stritt Christoph
• Schmidt Ulrich

Classifications

• H02M3/158 Primary

  including plural semiconductor devices as final control devices for a single load · CPC title

• H02M3/1555

  for the generation of a regulated current to a load whose impedance is substantially inductive · CPC title

• H02M1/009

  having two or more independently controlled outputs (for DC-DC converter with intermediate AC H02M3/33561) · CPC title

• H02M5/2932

  with automatic control of output voltage, current or power · CPC title

• F16D2500/3028

  Voltage · CPC title