34results about How to "Implement over temperature protection" patented technology

A semiconductor laser unit driving power supply with an over-temperature protection function comprises a precise reference source, a temperature detector, a temperature controller and a constant flow source driver, wherein the precise reference source provides precise reference voltage for the temperature detector and the constant flow source driver, the temperature detector detects temperature of a semiconductor laser unit and inputs a temperature signal to a temperature control system to generate a temperature control signal, and the temperature control signal controls the constant flow source driver to output a current. When the temperature is detected to be higher than or equal to T0, current of semiconductor laser unit is reduced, and therefore heat productivity and temperature of the semiconductor laser unit are reduced, and the semiconductor laser unit is effectively protected. When the temperature is detected to be lower than T0, driving current of the semiconductor laser unit stays the same.

The invention provides an IGBT junction temperature estimation system and method based on the temperature of an emitter power terminal. The system comprises a temperature measurement element, a temperature collection circuit, an IGBT gate driver, and a main controller, wherein the temperature measurement element is used for measuring the temperature of an IGBT power emitter terminal, the IGBT gatedriver comprises a gate drive and protection circuit and a temperature acquisition circuit, the gate drive and protection circuit is mainly used for on-off control and short circuit protection of a power device IGBT, the temperature acquisition circuit is used for acquiring a temperature signal, outputted by the temperature measurement element, on the IGBT power emitter terminal, and the main controller is used for sending a gate trigger signal to the IGBT gate driver, receiving a temperature signal on the IGBT power emitter terminal transmitted by the IGBT gate driver, and estimating the IGBT junction temperature according to the temperature signal on the IGBT power emitter terminal. According to the system, the over-temperature protection of the IGBT is realized, and IGBT temperature estimation is realized on the controller side.

The invention discloses an overheat protection circuit which comprises a resistance voltage division array, a comparator, a negative temperature coefficient voltage branch circuit and an output shaping circuit, wherein the protection circuit works under stable supply voltage; the resistance voltage division array carries out voltage division on the supply voltage to generate setting potential for setting thermal shutoff threshold temperature; the setting potential is compared with the voltage generated by the negative temperature coefficient voltage branch circuit by the comparator to generate a control signal; and the control signal is shaped and output by the output shaping circuit. The overheat protection circuit provided by the invention can overcome the influence of process deviation in the manufacturing process of an integrated circuit, and accurately generates a shutoff signal at a preset temperature spot to control the shutoff of a protected circuit or an auxiliary circuit thereof, thus realizing overheat protection of the circuit. In addition, the protection circuit has no special requirements for the manufacturing process.

The invention relates to the field of an LED, and particularly to an over-temperature protection circuit and system for an LED lamp. The input voltage at an inverted input end of a first comparator is changed by a thermistor; meanwhile, the over-temperature protection for the LED lamp is realized by hysteretic characteristics formed by a feedback circuit formed by a fourth resistor that is connected between a first junction point and the output end of the first comparator in series; the invention also provides an over-temperature protection system for the LED lamp; a temperature signal is obtained through a temperature sensor; the input voltage input to a hysteretic temperature control unit is adjusted according to the temperature signal so as to control the operating on-off states of the LED lamp; and meanwhile, when the output voltage of the hysteretic temperature control unit is zero, a trigger signal is generated by a zero voltage trigger unit to trigger an alarm unit to sent out an alarm so as to realize the in-time over-temperature protection for the LED lamp.

The embodiment of the invention provides a fan failure over-temperature protection method, device and system. The fan failure over-temperature protection method comprises the steps: firstly, the current temperature of a to-be-detected switch tube is obtained, then whether a fan loses efficacy or not is judged, if yes, the input amount of fan failure over-temperature protection is determined as thecurrent temperature, if not, the input amount of fan failure over-temperature protection is determined as a first preset value, the current temperature is used as the return difference of fan failureovert-temperature protection, and a threshold value of fan failure over-temperature protection is determined based on the current temperature; and then, whether the input amount is greater than the threshold value or not is judged, and if yes, over-temperature protection is carried out. It can be seen that according to the fan failure over-temperature protection method, the threshold value and the input amount are determined according to the detected current temperature and a fan failure state, over-temperature protection is triggered when the input amount is greater than the threshold value,the threshold value of over-temperature protection is determined by the current temperature and is not a fixed value, and thus the accuracy of over-temperature protection can be improved while a UPSafter a fan failure is subjected to over-temperature protection.

The invention provides a battery on-line monitoring method, device, equipment and system. The method comprises the steps: acquiring, in real time, first operation parameter data corresponding to at least one battery in a one-to-one mode and second operation parameter data corresponding to a battery pack comprising at least one battery; monitoring whether the first operation parameter data and thesecond operation parameter data are abnormal or not, and sending a first-stage alarm signal to an upper computer if the first operation parameter data and the second operation parameter data are abnormal; monitoring the variable quantities of the first operation parameter data and the second operation parameter data, and comparing the variable quantities with a first threshold value and a second threshold value respectively; and when the variable quantity of the first operation parameter data is greater than a first threshold value and the variable quantity of the second operation parameter data is greater than a second threshold value, sending a second-stage alarm signal to the upper computer, and meanwhile, cutting off battery power supply to realize fault protection. Compared with the prior art, the method has the advantages that the battery operation state can be monitored in real time, an alarm signal is sent in time to remind a user, battery power supply is cut off when a seriousfault occurs, and serious safety accidents are avoided. Besides, the battery temperature threshold value is monitored in real time, and the battery over-temperature protection is realized by monitoring the abnormality of the temperature variation of the battery in real time, so that the reaction is sensitive, the accuracy is high, and the misjudgment risk is greatly reduced.