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US-12620645-B2 - Emergency lighting driver and operation method thereof

US12620645B2US 12620645 B2US12620645 B2US 12620645B2US-12620645-B2

Abstract

An emergency driver ( 100 ) of this disclosure for driving emergency lighting means comprises a battery ( 101 ) operably coupled to the emergency lighting means, a preferably resistive temperature sensor ( 104 ) configured to generate a temperature signal (Ts) corresponding to a temperature of the battery ( 101 ), at least a resistive heating element ( 102 ) configured to increase the temperature of the battery ( 101 ) by a heating operation, and a controller ( 106 ) configured to perform in a time multiplex manner, the reading of the temperature sensor ( 104 ) and the operation of the resistive heating element ( 102 ).

Inventors

  • Jagjitpati Shukla
  • Deepak Makwana

Assignees

  • TRIDONIC GMBH & CO KG

Dates

Publication Date
20260505
Application Date
20230925
Priority Date
20220930

Claims (18)

  1. 1 . An emergency driver ( 100 ) for driving emergency lighting means comprising: a battery ( 101 ) operably coupled to the emergency lighting means, a temperature sensor ( 104 ) configured to generate a temperature signal (Ts) corresponding to a temperature of the battery ( 101 ), at least a resistive heating element ( 102 ) configured to increase the temperature of the battery ( 101 ) by a heating operation, and a controller ( 106 ) configured to perform in a time multiplex manner, the reading of the temperature sensor ( 104 ) and the operation of the resistive heating element ( 102 ).
  2. 2 . The emergency driver according to claim 1 , wherein the controller ( 106 ) is configured to read the temperature signal (Ts) generated by the temperature sensor ( 104 ) to measure the temperature of the battery ( 101 ) in a first cycle, and further to provide a controlled voltage (V T ) to the resistive heating element ( 102 ) for the heating operation based on the measured temperature of the battery ( 101 ) in a following second cycle.
  3. 3 . The emergency driver according to claim 2 , wherein the temperature sensor ( 104 ) and the resistive heating element ( 102 ) are operably coupled to a common terminal (T), whereby the controller ( 106 ) is configured to read the temperature signal (Ts) from the common terminal (T) in the first cycle and further to provide the controlled voltage (V T ) to the common terminal (T) in the second cycle.
  4. 4 . The emergency driver according to claim 3 , wherein the temperature sensor ( 104 ) and the resistive heating element ( 102 ) are coupled along a single electrical path ( 201 ) with respect to the common terminal (T).
  5. 5 . The emergency driver according to claim 1 , further comprising means ( 202 ) for bypassing the temperature sensor ( 104 ), whereby the controller ( 106 ) is configured to bypass the temperature sensor ( 104 ) in the second cycle.
  6. 6 . The emergency driver according to claim 1 , further comprising a first switching element (M 1 ) and a second switching element (M 2 ), whereby the controller ( 106 ) is configured to operate the first switching element (M 1 ) and the second switching element (M 2 ) in a complementary manner, wherein a conduction period of the first switching element (M 1 ) corresponds to the first cycle and a conduction period of the second switching element (M 2 ) corresponds to the second cycle.
  7. 7 . The emergency driver according to claim 6 , wherein the controller is configured to operate the first switching element (M 1 ) and the second switching element (M 2 ) in the complementary manner with a fixed frequency.
  8. 8 . The emergency driver according to claim 6 , wherein the controller is configured to control the conduction period of the second switching element (M 2 ) based on a predetermined temperature of the battery ( 101 ).
  9. 9 . The emergency driver according to claim 6 , wherein the first switching element (M 1 ) and the second switching element (M 2 ) are active switching elements.
  10. 10 . The emergency driver according to claim 1 , wherein the controller ( 106 ) is configured to read the temperature signal (Ts) generated by the temperature sensor ( 104 ) during the first cycle at a predetermined delay (d) in time after the initiation of the first cycle.
  11. 11 . The emergency driver according to claim 1 , wherein the controller ( 106 ) is configured to average the measured temperature of the battery ( 101 ) based on the temperature signal (Ts) generated by the temperature sensor ( 104 ) over a predetermined number of cycles.
  12. 12 . The emergency driver according to claim 1 , wherein the battery ( 101 ) is a Lithium-ion battery.
  13. 13 . The emergency driver according to claim 1 , wherein the temperature sensor ( 104 ) is a thermistor.
  14. 14 . An emergency lighting system ( 400 ) comprising: the emergency driver ( 100 ) according to claim 1 , emergency lighting means ( 401 ) operably coupled to the emergency driver ( 100 ), and a housing ( 402 ) encompassing the emergency driver ( 100 ) and the emergency lighting means, the housing being mountable relative to a wall or a surface.
  15. 15 . The emergency driver according to claim 1 wherein the temperature sensor is a resistive temperature sensor.
  16. 16 . A method ( 500 ) for a time-multiplexed resistive heating and temperature sensing of a battery for an emergency driver comprising: generating ( 501 ) a temperature signal corresponding to a temperature of the battery and measuring the temperature of the battery based on the temperature signal in a first cycle, and providing ( 502 ) a controlled voltage to increase the temperature of the battery by a heating operation based on the measured temperature of the battery in a following second cycle.
  17. 17 . The method according to claim 16 , wherein the method further comprising: reading the temperature signal from and providing the controlled voltage to a common terminal of the emergency driver.
  18. 18 . The method according to claim 16 wherein a resistive temperature sensor is used to generate the temperature signal.

Description

CROSS REFERENCE TO RELATED APPLICATIONS The present application is the U.S. national stage application of international application PCT/EP2023/076433 filed Sep. 25, 2023, which international application was published on Apr. 4, 2024 as International Publication WO 2024/068566 A1. The international application claims priority to European Patent Application No. 22198998.1 filed Sep. 30, 2022. TECHNICAL FIELD OF THE INVENTION The present disclosure relates to an emergency driver for driving emergency lighting means, and more particularly, to an emergency driver for driving emergency lighting means that can perform both the temperature sensing and heating of the battery provided therein in a time multiplexed manner. BACKGROUND OF THE INVENTION Generally, charging a Lithium battery under sub-zero temperatures should be avoided due to a chemical phenomenon called “Lithium Plating”, which may be caused by the charge current forcing the lithium ions to move at a faster reaction rate than usual and accumulate on the surface of the anode. Emergency driver applications for driving, especially outdoor emergency lights or in other demanding industrial applications, may be affected by the phenomenon when attempted to charge the battery therein under sub-zero or at low temperatures. One possible solution to charge the battery under sub-zero temperatures is to embed a heating element around the battery to rise the temperature of the battery to an acceptable temperature when the charging should be started. However, the additional circuitry, especially the additional terminals that may require to supply the heating element, may increase the overall size of the circuitry as well as may raise the complexity of packaging and production of emergency drivers, especially due to the extended number of wire connections or supply terminals. SUMMARY OF THE INVENTION In view of the above, embodiments of this disclosure aim to provide an emergency driver for driving emergency lighting means, such as LED lighting means, an emergency lighting system, and an operation method. An objective is to provide an emergency lighting means driving scheme that can perform both the temperature sensing and heating of the battery provided therein, especially in a compact (i.e., size or area constrain) and a simplified (i.e., connection, packaging, or production complexities) manner. These and other objectives are achieved by the embodiments of this disclosure as described in the enclosed independent claims. Advantageous implementations of the embodiments are further defined in the dependent claims. According to a first aspect of this disclosure, an emergency driver is provided for driving emergency lighting means. The emergency driver comprises a battery operably coupled to the emergency lighting means, a preferably resistive temperature sensor configured to generate a temperature signal corresponding to a temperature of the battery, at least a resistive heating element configured to increase the temperature of the battery by a heating operation, and a controller configured to perform in a time multiplex manner, the reading of the temperature sensor and the operation of the resistive heating element. Advantageously, the heating operation to increase the battery temperature and the reading of the temperature sensor can be performed in a multi-tasking fashion to detect the battery temperature as well as to provide supply power to the battery heating element. In an implementation form of the first aspect, the controller is configured to read the temperature signal generated by the temperature sensor to measure the temperature of the battery in a first cycle or temperature sensing phase, and further to provide a controlled voltage to the resistive heating element for the heating operation based on the measured temperature of the battery in a following second cycle or battery heating phase. In this regard, the temperature sensing phase and the battery heating phase can be performed in any order required by an application. For instance, the controller may first initiate the temperature sensing phase to measure the battery temperature and in the following battery heating phase, the controller may accordingly supply a controlled power to the battery heating element for the heating operation. Alternatively, the controller may first initiate the battery heating phase to supply the controlled power to the battery heating element for the heating operation, and in the following temperature sensing phase, the controller may measure the battery temperature. In an implementation form of the first aspect, the temperature sensor and the resistive heating element are operably coupled to a common terminal, whereby the controller is configured to read the temperature signal from the common terminal in the first cycle and further to provide the controlled voltage to the common terminal in the second cycle. Advantageously, the number of required terminals or wire connections,