Inferential temperature measurement of an electrochromic device
AssigneeSage Electrochromics, Inc.
InventorsJames F. Ingalls, Freek Stoffelen
Life of this patent
Estimating the term…
Abstract
An electrochromic device driver system having inferential temperature measurement of the electrochromic device. The inferred temperature measurements enable the system to determine the maximum driving voltages to improve the speed of varying the transmissivity levels of the electrochromic device without damaging the device.
Claims35
An optimizer for driving an electrochromic (EC) device, comprising:
- a current sensor connected to an output of an EC driver;
- a voltage sensor connected to the output of the EC driver;
- and
- a processor connected to said current sensor and to said voltage sensor.
An electrochromic (EC) device driver system comprising:
- a current indicator connected to an output of a driver;
- a voltage indicator connected to the output of the driver;
- a processor connected to said current indicator, voltage indicator and the driver;
- wherein:
- said processor determines a parameter at the output of said driver from current and voltage indications at the output of the driver;
- and
- said processor determines maximum but safe voltages to be at the output of the driver.
A method for high speed driving an electrochromic (EC) device, comprising:
- determining temperature information of the EC device by measuring the voltage and current applied to the EC device;
- and
- driving the EC device with a maximum but safe voltage according to the temperature information of the EC device.
An electrochromic (EC) device driver system comprising:
- a driver connected to the EC device;
- a current sensor connected to an output of said driver;
- a voltage sensor connected to the output of said driver;
- and
- a processor connected to said driver, current sensor and voltage sensor;
- wherein:
- said processor determines EC device resistance from information from said current sensor and said voltage sensor;
- said processor provides signals to said driver;
- said driver provides maximum but safe voltages in accordance with a table of EC device resistance versus safe maximum voltages for driving the EC device through a transmission level change.
A process for driving an electrochromic (EC) device comprising:
- applying a driving signal to bleach or color the EC device, wherein initially the driving signal has a voltage amplitude that is harmless to the EC device at any temperature;
- measuring a first voltage amplitude of the driving signal applied to the EC device;
- measuring a second voltage amplitude of the driving signal applied to the EC device;
- measuring a first current amplitude of the driving signal applied to the EC device;
- measuring a second current amplitude of the driving signal applied to the EC device;
- determining a voltage amplitude difference between the first voltage amplitude and the second voltage amplitude;
- determining a current amplitude difference between the first current amplitude and the second current amplitude;
- determining a first resistance from the voltage amplitude difference and the current amplitude difference;
- determining a second resistance by subtracting a third resistance from the first resistance, wherein the third resistance is a static resistance of the EC device that is static relative to temperature change of the EC device;
- and
- adjusting the first and second voltage amplitudes to a maximum amplitude that is harmless to the EC device at a present temperature that is inferred from the second resistance.
An electrochromic (EC) device driver system having inferential temperature measurement, comprising:
- means for measuring input resistance to an EC device;
- means for inferring temperature of the EC device from the input resistance, connected to said means for measuring;
- and
- means for determining an amplitude of the driving voltage, connected to said means for inferring.
An electrochromic (EC) device driver system, comprising:
- means for measuring parameters of electrical input to an EC device;
- means for determining the transmissivity of the EC device;
- means for inferring the temperature of the EC device from the parameters of the electrical input to the EC device and the transmissivity of the EC device;
- and
- means for setting the amplitude of a voltage to the EC device based on the temperature of the EC device.
A method for inferring the temperature of an EC device and adjusting a voltage for driving the EC device, comprising:
- measuring parameters of electrical input to an EC device;
- inferring the temperature of the EC device from the parameters of the electrical input to the EC device;
- and
- adjusting the amplitude of the voltage to the EC device based on the temperature of the EC device.
A method for inferring the temperature of an EC device and adjusting a voltage for driving the EC device, comprising:
- measuring parameters of electrical input to an EC device;
- measuring the transmissivity of the EC device;
- inferring the temperature of the EC device from the parameters of the electrical input to the EC device and the transmissivity of the EC device;
- and
- adjusting the amplitude of the voltage to the EC device based on the temperature of the EC device.
Dependencies are inferred from the claim text.