Wireless adaptation of lighting power supply

Methods, systems, and apparatus, for wirelessly controlling a power supply device that controls a load. A wireless adapter includes a wireless communication device that receives transmissions from a wireless controller, a serial interface for a serial data connection to a power supply processing device integrated in the power supply device, an adapter processing device that receives the control signals the wireless communication device outputs, generates the control commands from the control signals, and outputs the control commands to the serial interface to cause the power supply processing device to control power provided to the load in a manner specified by the control commands, and an adapter power circuit that receives regulated direct current (DC) power from the power supply device and is powered from the regulated DC power received, and provides power to the wireless communication device and the adapter processing device.

BACKGROUND

This specification relates to wireless adaptation of lighting power supplies.

Lighting control within buildings is traditionally limited to control of lights in the ceiling that illuminate a general area. This type of control is typically referred to as ambient lighting control. Typically, the power supplies of the lighting devices are controlled by wired control systems and/or by wireless control systems.

Example wired control systems are a combination of wired connections connecting a lighting power supply to a dimmer and power control device and a control signal source that either manually or automatically generates the control signals to adjust the power supply of the lighting device. Such wired control systems include on/off relays and/or phase cut circuits interposed between mains power conductors and a lamp power supply to provide on/off and dimming control, and relays in conjunction with signal control circuits, such as a 0V-10V signal generator that generates an analog signal indicative of a dimming level. While on/off signaling itself is simply a case of whether the power to the ballast is provided or not, support for phase-cutting and 0-10V signaling must be specifically designed into the ballast. This adds cost to the ballast and cost to the control equipment delivering the signals to the ballast.

An example wireless control system is a control device that receives a control signal wirelessly and, through a short wired connection, controls the power supply. Wireless control systems often leverage existing wired control systems and interfaces to enable wireless controls. For example, a wireless switch could provide manual controls for turning the lighting on/off and to dim the lighting by use of a triac for a phase-cut dimming ballast. Likewise, a wireless adapter can include a relay and a 0-10V signal generation circuit and receive wireless signals from a wireless controller to control a dimming ballast driven, in part, by the 0-10V signal.

While the wireless control systems do wirelessly enable a power supply to provide for wireless control, the device that provides the wireless control itself needs to include a mains power (e.g., 120 V, 60 Hz) conditioning and converter circuit to generate regulated DC power, and additional power regulator circuits to generate analog control signals (e.g., a 12 V regulator circuit to generate the 0-10 V dimming signal). Additionally, in some situations, the device that provides the wireless control is deployed in-line with the mains power. Accordingly, the device requires a relay to interrupt power to the controlled power supply. These components add additional expenses to the cost of the devices.

SUMMARY

This specification describes technologies relating to wireless adapters. In general, one innovative aspect of the subject matter described in this specification can be embodied in systems that include a wireless communication device that receives transmissions from a wireless controller, the transmissions including control signals specifying control commands for the power supply device, and to output the control signals; a serial interface for a serial data connection to a power supply processing device integrated in the power supply device; an adapter processing device in data communication with the wireless communication device and that receives the control signals the wireless communication device outputs, generates the control commands from the control signals, and outputs the control commands to the serial interface, wherein the control commands cause the power supply processing device to control power provided to the load in a manner specified by the control commands; and an adapter power circuit that receives regulated direct current (DC) power from the power supply device and is powered from the regulated DC power received, and provides power to the wireless communication device and the adapter processing device. Other embodiments of this aspect include corresponding methods, apparatus, and computer programs, configured to perform the actions of the methods, encoded on computer storage devices.

Particular embodiments of the subject matter described in this specification can be implemented to realize one or more of the following advantages. In some implementations, the wireless adapter receives regulated direct current (DC) power from the power supply of a device being controlled by the wireless adapter, and thus leverages off the existing power and conditioning circuitry that already exists in the device being controlled, thereby reducing fabrication costs. The electrical code requirements for using a using a low voltage DC power supply are less stringent than the code requirements for using a mains power supply connection, and thus the wireless adapter can be placed with greater flexibility.

In some implementations, the wireless adapter generates control commands from control signals received over a wireless channel, and outputs the control commands to a serial interface that establishes data communication with the device being controlled. By providing a serial data interface, the wireless adapter need not include specialized circuitry for generating the control signals.

Additionally, reducing the circuitry also reduces the overall power consumption. As the wireless adapters are typically deployed by the hundreds in commercial buildings, the savings for costs associated with the power consumption is significant.

The traditional interfaces described above provide limited interfaces between controlling devices and the power supply device being controller. For example, these interfaces are often limited to turning the ballast on or off, and providing dimming controls. Additional types of communication, which include collecting information about electricity consumption (for instance, for ballasts with integrated power meters) or ballast health/failure detection, are not be possible with traditional interfaces. By exposing a serial interface that a processing device on the power supply device being controlled can use to communicate to another processing device, a wider range of communication can be made available.

DETAILED DESCRIPTION

FIG. 1is a block diagram illustrating a lighting system100controlled by a wireless controller108and wireless adapters120. The system100includes four lighting power supplies (LPS)110that are connected to a wall switch106. The lighting power supplies110can, for example, be lighting ballasts in a conference room and which power fluorescent lights. Other lighting power supply devices can also be used, such as a light emitting diode (LED) driver for a LED lighting load, or a high intensity discharge (HID) striker for a HID lamp, etc.

The wall switch106is connected to a power source102, e.g., a single phase AC power line. As shown, the wall switch106is a manually activated switch that provides a connection or breaks a connection to the power source102. In other implementations, the wall switch can be a wireless device that provides control signals to the wireless adapters120to control the lighting power supplies110.

Each of the wireless adapters120are connected to a corresponding lighting power supply110. In some implementations, each wireless adapter120receives direct current power from the lighting power supply110, as will be described in more detail with respect toFIG. 2below. Additionally, each wireless adapter120is in data communication with a corresponding lighting power supply110by means of a serial communication interface, which will also be described in more detail with respect toFIG. 2below.

Each wireless adapter120also includes a wireless transceiver that sends and receives data to and from a controller108. The controller108includes power management software that performs power management and power optimization routines to adjust lighting provided by the lighting system100. As used herein, a “wireless controller” is any device that provides a controller functionality and which sends control signals to the wireless adapters120. A wireless controller can be a dedicated controller, or can be integrated into another device, such as a wireless switch, another wireless adapter, or a wireless sensor. Example power management and optimization routines include daylighting, dimming in the absence of detected occupancy, and timer control of lighting settings. Other power management routines can also be implemented by the controller108.

For the purposes of illustration only, the wireless devices may conform to the ZigBee specification, which is based on the IEEE 802.15.4 standard. The IEEE 802.15.4 standard is a standard for low-rate wireless personal area networks (LR-WPANs). The ZigBee specification defines a suite of high level communication protocols that use low-power and low-bandwidth digital radios. The low power consumption and low bandwidth requirements of a ZigBee device reduces cost and prolongs battery life, and thus such devices are often used for sensors, monitors and controls. Other devices that communicate according to other wireless protocols can also be used, and thus the devices and processes described below can be applied to other types of wireless networks as well.

FIG. 2is a more detailed block diagram of one of the wireless adapters120and a lighting power supply110. As will be described in more detail below, the wireless adapter120is configured to leverage off the existing power control circuitry of the lighting power supply110to reduce and/or eliminate power conversion and conditioning circuitry within the wireless adapter. Additionally, in some implementations, the wireless adapter110includes a digital communication interface, such as a serial interface, that provides a digital data communication link between a processing device in the wireless adapter120and a processing device in the lighting power supply110. As with the previous feature, a serial data communication link eliminates the need for additional circuitry within the wireless adapter120that generates specific control signals for the lighting power supply110. Example serial interfaces include universal asynchronous receiver/transmitter (UART), serial peripheral interface (SPI), etc.

The wireless adapter120includes a wireless communication device, such as a wireless transceiver122that receives transmissions from the wireless controller108. The transmissions including control signals specifying control commands for the lighting power supply device110, and outputs the control signals to a processing device124in the adapter120. The adapter processing device124is in data communication with the wireless transceiver122, and receives the control signals. The adapter processing device124generates the control commands from the control signals (e.g., by using the control signals if the control signals are identical to control commands, or by interpreting the control signals to generate the control commands) and outputs the control commands to the serial interface126.

The wireless adapter120also includes an adapter power circuit128that receives regulated direct current power from the power supply device110by at least one conductor129and is powered from the regulated DC power received. For example, the power circuit128may be configured to receive a DC voltage of 5 volts or less (e.g., 3.6V). The adapter power circuit128provides power to the wireless communication device122and the adapter processing device124. In some implementations, the power circuit128includes protection circuitry to protect the wireless adapter120from power surges and discharges. Example protection circuitry includes passive DC limiters, spark gaps, and the like. In some implementations, the protection circuitry includes only passive components.

The lighting power supply110includes a power subsystem112that receives AC power input, e.g., from mains104, and generates, among other signals and power output, a regulated power supply signal for a processing device114, and a power supply for a lighting load118. The power supply for the lighting load118can be either AC or DC and condition by one or more functions (e.g., phase/amplitude cutting, duty cycle adjustment, etc.), depending on the type of lighting load118that is powered by the power supply. The power subsystem112can include multiple different power conditioning circuits, e.g., the power subsystem112includes an AC/DC converter to generate DC power for DC powered components, and an AC conditioning circuit for powering AC lighting loads. The processing device114generates control signals that can instruct the power subsystem to adjust the power signal to control the lighting load118, e.g., to dim or brighten the lighting load118.

The processing device114is in data communication with a serial interface116that is connected to the serial interface126by at least one conductor132. The processing device114thus receives the control commands from the wireless adapter120, which, in turn, cause the power supply processing device114to control power provided to the load118in a manner specified by the control commands.

In some implementations, the control signals are digital signals and the control commands are digital signals that encode an analog value in a range from a first analog value to a second analog value that is different from the first analog value. For example, the control signal can be a digital signal that instructs the wireless adapter120dim or brighten the load118. In some implementations, the processing device114is programmed to interpret the digital representation of an analog signal ranging from 0 V to 10 V as a dimming signal. The data transmitted over the serial interface is thus a representation of the analog signal that ranges from 0 V to 10 V. In other implementations, the digital signal represents a directly specified setting and the processing device114interprets the digital signal to determine the setting and adjust the power to the lighting load118accordingly.

In addition to providing and receiving control data, the wireless adapter120can communicate with the processing device114of the power supply120and receive report status data, such as hours on, power consumption, system health, and the like, provided the processing device114is configured to track and provide such data.

Additional devices can be connected to the wireless adapter to provide additional control features.FIG. 3is a block diagram of the one of the wireless adapters120, the lighting power supply110, and a local wired control device140. One example local wired control device140is an environmental sensor circuit. For example, local wired control device140can include a power circuit142, an environmental sensor144, and an input/output interface146. The power circuit142is a local power input circuit that receives power from the adapter power circuit128and is powered from the power received from the adapter power circuit and provides power to the device140. In its most simple form, the power circuit142can be conductor connections with minimal protection circuitry, e.g., with optional spark gaps, as it need only provide a connection to the power circuit128for the other devices within the device140that are powered by the power circuit128. Accordingly, fabrication costs are reduced.

The environmental sensor144is a sensor that senses a physical stimulus of an environment and generates physical stimulus data indicative of the physical stimulus. A physical stimulus is a stimulus in an environment that is either indicative of a person's presence or indicative of an environmental change in the environment. For example, the motion of a person is a physical stimulus that can be detected by an occupancy sensor; the body heat of a person can be detected by a thermal sensor; and illumination level can be detected by a photo sensor, etc.

The environmental sensor144provides the stimulus data to the local input/output interface146, which, in turn, provides the stimulus data to the processing device124of the wireless adapter120by means of at least one conductor150and an input/output interface130.

In some implementations, the data provided by the device is analog data, e.g., an analog signal that is proportional to the physical stimulus the environmental sensor144detects. In other implementations, the data provided over the conductor150is serial data. In these implementations, the input/output interface130can be combined with the interface126. In still further implementations, both analog and digital data can be provided.

The processing device124, in turn, instructs the wireless transceiver122to transmit the sensor data to the controller108. The controller108, executing one or more power management routines, provides commands in response to the sensor data received. Such commands can be, for example, to dim the lighting load118, brighten the lighting load118, turn on the lighting load118, or turn off the lighting load118.

In some implementations, the wireless adapter120is packaged in a packaging that is separate from the power supply device110. The wireless adapter120can thus be mounted separately from the power supply device110. For example, if the power supply device110is a ballast for fluorescent lighting bank, the ballast is typically recessed within the ceiling. The wireless adapter120can thus be mounted on the surface of the ceiling to optimize reception and transmission of radio signals. Likewise, the local control device140can also be packaged in a package that is configured to be separately mounted from the wireless adapter120and the lighting power supply110. In some implementations, the packaging of the local control device140and the wireless adapter120can include mating surfaces that interlock and provide the data connections148and150. Accordingly, the wireless adapter120and the local control device140can be mounted as a single unit separate from the lighting power supply110.

In other implementations, the devices110,120and140can be connnected using wired connectors, such as RJ connectors (e.g., RJ11, RJ14, RJ25 or RJ45 wires). For example, between devices110and120, four active wires are provided, two for the connection between the power subsystem112and the power circuit128, and two for the serial connection between the interfaces116and126(one wire for each directional component). Between the devices120and140, there can be up to six wires, two for the power connection between the circuits128and142, two for analog signls (e.g., one wire for carrying a binary on/off signal and one wire for a 0-3.6V environmental readout signal), and two wires for serial communications.

FIG. 4is a block diagram of the one of the wireless adapters120, the lighting power supply110, and local wired control devices140and160. InFIG. 4, multiple devices140are connected to the adapter120, and each receive power from the power circuit128. Accordingly, up to n local wired control devices140can be connected to an adapter120, where n is a maximum limit as determined by a fan-out parameter of the power circuit128, or by the maximum I/O capabilities by the I/O circuit130.

Additionally, devices that need only serial I/O connections with the adapter120can also be connected by use the serial I/O circuit126. For example, another lighting power supply160can be connected by one or more conductors164and the serial I/O circuit162and controlled by the adapter120in a manner similar to the way the lighting power supply110is controlled. This lighting power supply160need not provide power to the adapter120, as the adapter120is receiving power from the lighting power supply110, nor does the lighting power supply160need power from the adapter120, as it has its own power source. Accordingly, once the adapter120receives power from a lighting power supply110, it can communicate with other devices that have their own power supplies, and can also provide power to other devices with which it is communicating, if necessary.

While this description uses the example of wireless control for lighting power supplies, the systems described herein applies to any communications technology. For instance, an adapter that is powered in the same way, and using microcontroller-to-microcontroller serial interface can be provide a wired communications technology, such as DALI, or BACNet (using RS-485). While the examples herein deals largely with the use of the system for wireless control, the inherent flexibility of the system to support other communications technologies for controls ensures that such an interface can also enable the benefits described here to be leveraged by control systems using other communications technologies.

Embodiments of the subject matter and the operations described in this specification can be implemented in digital electronic circuitry, or in computer software, firmware, or hardware, including the structures disclosed in this specification and their structural equivalents, or in combinations of one or more of them.

The term “processing device” or “processing system” encompasses all kinds of apparatus, devices, and machines for processing data, including by way of example a programmable processor, a computer, a system on a chip, or multiple ones, or combinations, of the foregoing The apparatus can include special purpose logic circuitry, e.g., an FPGA (field programmable gate array) or an ASIC (application-specific integrated circuit