Controller circuit for photovoltaic modules

Abstract

A controller circuit (100) for a PV module (102) is disclosed, comprising a receiver circuit (104) and a mode control and power conversion circuit (106). The receiver circuit (104) receives a first signal (108) from a transmitter circuit (116) associated with the PV module. The receiver circuit (104) changes a second signal (118) from a first state to a second state based on the first signal (108). The mode control and power conversion circuit (106) receives a DC string voltage (120) from a PV cell string (122) associated with the PV module (102), receives the second signal (118) from the receiver circuit (104), switches from a first mode to a second mode in response to the second signal (118) being changed to the second state, converts the DC string voltage (120) to a backup voltage (124) in the second mode, and provides the backup voltage (124) to a DC power line (110, 112) between the PV module and a DC to AC inverter in the second mode.

Description

Background Art

[0001] The National Electrical Code (NEC) applies to the construction of photovoltaic (PV) systems mounted on buildings. The 2014 version (2014 NEC) included requirements for rapid shutdown of controlled conductors outside the boundaries of a PV array. The 2017 version (2017 NEC) includes requirements for module-level shutdown.

[0002] Underwriters Laboratories (UL) 1741 includes requirements for PV Rapid Shutdown Equipment (PVRSE) and PV Rapid Shutdown System (PVRSS). In order to meet the requirements of the 2017 NEC and UL 1741, it is advantageous to have modules, inverters, charge controllers, and other equipment communicate with each other. In addition, it is desirable to have a single communication protocol to provide interoperability between different components from different manufacturers that are required to participate in PVRSS.

[0003] For example, the SunSpec interoperability specification (Communication Signaling for Rapid Shutdown, Version 34, August 21, 2017) defines how the operating status of the entire PV system is propagated to the individual power producing components that comprise the PV system. The SunSpec specification also describes the requirements and constraints associated with the power line communication (PLC) network used to support PVRSS. PVRSS is a collection of components and communication protocols used to meet rapid shutdown requirements as defined by NEC 2014 or NEC 2017. The components of the rapid shutdown communication system are the initiator, transmitter, and receiver. The SunSpec specification supports the rapid shutdown requirements of any PV system governed by NEC 2014, NEC 2017, or applicable UL standards, regardless of the system configuration. Summary of the invention

[0004] An example of a controller circuit for a PV module includes a receiver circuit and a mode control and power conversion circuit. The receiver circuit receives a first signal from a transmitter circuit associated with the PV module. The receiver circuit changes a second signal from a first state to a second state based on the first signal. The mode control and power conversion circuit receives a DC string voltage from a PV cell string associated with the PV module. The mode control and power conversion circuit also receives a second signal from the receiver circuit. The mode control and power conversion circuit switches from the first mode to the second mode in response to the second signal being changed to a second state. The mode control and power conversion circuit converts the DC string voltage to a backup voltage in the second mode. The mode control and power conversion circuit provides the backup voltage to a DC power line between the PV module and the DC to AC inverter in the second mode.

[0005] An example of a method for rapidly shutting down a PV module includes receiving a first signal at a receiver circuit of a controller circuit for the PV module from a transmitter circuit associated with the PV module. The receiver circuit changes a second signal from a first state to a second state based on the first signal. A mode control and power conversion circuit of the controller circuit receives a DC string voltage from a PV cell string associated with the PV module. The mode control and power conversion circuit receives a second signal from the receiver circuit. The mode control and power conversion circuit switches from a first mode to a second mode in response to the second signal being changed to a second state. The mode control and power conversion circuit converts the DC string voltage to a backup voltage in the second mode. The mode control and power conversion circuit provides the backup voltage to a DC power line between the PV module and a DC to AC inverter in the second mode.

[0006] An example of a system for rapidly shutting down a PV module includes a starter, a transmitter circuit, and a controller circuit. The starter switches between a first condition and a second condition. The first condition sets a fourth signal to a first state to enable the system to operate in a first mode. The second condition changes the fourth signal to a second state to trigger the system to operate in a second mode. The transmitter circuit receives the fourth signal from the starter. The transmitter circuit generates a first signal in response to the fourth signal. The controller circuit includes a receiver circuit and a mode control and power conversion circuit. The receiver circuit receives a first signal from the transmitter circuit. The receiver circuit changes the second signal from a first state to a second state based on the first signal. The mode control and power conversion circuit receives a DC string voltage from a PV cell string associated with a PV submodule of the PV module. The mode control and power conversion circuit also receives a second signal from the receiver circuit. The mode control and power conversion circuit switches from the first mode to the second mode in response to the second signal being changed to a second state. The mode control and power conversion circuit converts the DC string voltage to a backup voltage in the second mode. The mode control and power conversion circuit provides the backup voltage to a DC power line between the PV module and the DC to AC inverter in the second mode. BRIEF DESCRIPTION OF THE DRAWINGS

[0007] Figure 1 is a block diagram of an example of a controller circuit for a PV module.

[0008] Figure 2 is a block diagram of examples of multiple controller circuits for PV modules.

[0009] Figure 3 is a block diagram of another example of a controller circuit for a PV module.

[0010] Figure 4 It is shown Figure 3 A timing diagram showing an example of the timing of the selection signals is shown.

[0011] Figure 5 is a block diagram of another example of a controller circuit for a PV module.

[0012] Figure 6 It is shown Figure 5 A timing diagram showing an example of the timing of the selection signals is shown.

[0013] Figure 7 is a block diagram of another example of a controller circuit for a PV module.

[0014] Figure 8 It is shown Figure 7 A timing diagram showing an example of the timing of the selection signals is shown.

[0015] Fig. 9 is a block diagram of an example of an integrated circuit (IC) that facilitates rapid shutdown of a PV module.

[0016] Fig.10 is a flow chart of an example of a method for rapid shutdown of a PV module.

[0017] Fig.11 Combination Fig.10 is a flow chart of another example of a method for rapid shutdown of a PV module.

[0018] Fig.12 Combination Fig.10 and Fig.11 is a flow chart of another example of a method for rapid shutdown of a PV module.

[0019] Fig.13 Combination Fig.10 is a flow chart of another example of a method for rapid shutdown of a PV module.

[0020] Fig.14 Combination Fig.10 is a flow chart of another example of a method for rapid shutdown of a PV module.

[0021] Fig.15 Combination Fig.10 is a flow chart of another example of a method for rapid shutdown of a PV module.

[0022] Fig.16 Combination Fig.10 and Fig.15 is a flow chart of another example of a method for rapid shutdown of a PV module.

[0023] Fig.17 is a block diagram of an example of a PV Rapid Shutdown System (PVRSS) for a PV module. DETAILED DESCRIPTION

[0024] In the drawings, like reference numerals refer to like elements throughout, and the various features are not necessarily drawn to scale. In the following description and claims, the terms "includes," "comprising," "having," "having," "with," or variations thereof are inclusive in a manner similar to "comprising," and thus mean "including, but not limited to ..."

[0025] Figure 1 An example of a controller circuit 100 for a PV module 102 is shown. The controller circuit 100 includes a receiver circuit 104 and a mode control and power conversion circuit 106. For example, Figure 1 The controller circuit 100 is referred to as a fast shutdown controller circuit. The receiver circuit 104 receives a first signal 108 from a transmitter circuit 116 associated with the PV module 102. For example, Figure 1 The first signal 108 is referred to as a keep alive (KA) signal. The KA signal may be transmitted one or more times within a frame. The frame may be transmitted periodically or asynchronously within a first predetermined time period. In another example, the first signal 108 may be a shutdown signal. The shutdown signal may be transmitted asynchronously in response to a shutdown event. The shutdown signal may be transmitted multiple times to ensure detection. The receiver circuit 104 changes the second signal 118 from a first state to a second state based on the first signal 108. For example, Figure 1 The second signal 118 is referred to as a permission to operate (PTO) signal. The first state of the second signal 118 is, for example, an activated state, an on state, a logic 1 state, or any suitable state indicating that normal operation of the controller circuit 100 is enabled. The second state of the second signal 118 is, for example, a deactivated state, an off state, a logic 0 state, or any suitable state indicating that normal operation of the controller circuit 100 is disabled.

[0026] The mode control and power conversion circuit 106 receives a DC string voltage 120 from a PV cell string 122 associated with the PV module 102. The mode control and power conversion circuit 106 also receives a second signal 118 from the receiver circuit 104. The mode control and power conversion circuit 106 switches from a first mode (e.g., a normal mode) to a second mode (e.g., a shutdown mode) in response to the second signal 118 being changed to a second state. The mode control and power conversion circuit 106 converts the DC string voltage 120 to a backup voltage 124 in the second mode. The mode control and power conversion circuit 106 provides the backup voltage 124 to the DC power lines 110, 112 between the PV module 102 and the DC to AC inverter 114 via the output node 125 in the second mode.

[0027] In one example of the PV module 102, the DC power lines 110, 112 carry the first signal 108 to the RLC filter 126 or any suitable filter that provides a filtered version of the first signal 108 to the receiver circuit 104. In another example of the PV module 102, the first signal 108 is a wireless communication signal (e.g., WiFi, Zigbee, or any suitable wireless signal), and the receiver circuit 104 includes a wireless receiver for receiving the first signal 108 from the transmitter circuit 116. In another example of the PV module 102, the first signal 108 is a wired control line communication signal (e.g., wire, cable, bus, or any conductor suitable for a wired control signal), and the receiver circuit 104 includes an input node for receiving the first signal 108 from the transmitter circuit 116. In one example, a Schottky diode 128 or any suitable bypass diode is connected from the output node 125 of the controller circuit 100 to the RLC filter 126 or the DC power line return portion 112. In the case where the controller circuit 100 is not outputting a voltage, the Schottky diode 128 allows DC current to pass.

[0028] In another example of the controller circuit 100, the PV module 102 includes the controller circuit 100. In another example, the controller circuit 100 is an IC. In another example of the controller circuit 100, the backup voltage 124 is 2.5 volts DC or less. In yet another example of the controller circuit 100, the backup voltage 124 is 1 volt DC or less. In other examples, the backup voltage 124 is any suitable DC voltage that is safe for maintenance technicians, service personnel, inspectors, and / or emergency first responders.

[0029] In another example of the controller circuit 100, the backup voltage 124 on the DC power lines 110, 112 provides power to the transmitter circuit 116 during the second mode. In another example of the controller circuit 100, the backup voltage 124 on the DC power lines 110, 112 provides power to the DC to AC inverter 114 during the second mode.

[0030] In another example of the controller circuit 100, the second mode and the backup voltage 124 on the DC power lines 110, 112 comply with safety standards for rapid shutdown of PV systems in NEC 2014, NEC 2017, and SunSpec Interoperability Specification (Communication Signals for Rapid Shutdown, Version 34).

[0031] In another example of the controller circuit 100, the first signal 108 is repeatedly transmitted by the transmitter circuit 116 to enable normal operation of the PV module 102. The receiver circuit 104 sets the second signal 118 to the first state based on the presence of the first signal 108. The receiver circuit 104 changes the second signal 118 to the second state based on the absence of the first signal 108. In one example, after filtering and demodulating the communication signal from the DC power lines 110, 112, the receiver circuit 104 repeatedly detects the presence of the first signal 108. For example, if at least one first signal 108 is detected within a second predetermined time period, the receiver circuit 104 considers the first signal 108 to be present. Conversely, if the first signal 108 is not detected within the second predetermined time period, the receiver circuit 104 considers the first signal 108 to be absent. The second predetermined time period is, for example, less than or equal to the first predetermined time period associated with the repeated transmission of the first signal 108.

[0032] In another example of the controller circuit 100, the first signal 108 is transmitted at least once by the transmitter circuit 116 to disable normal operation of the PV module 102. The receiver circuit 104 sets the second signal 118 to the first state based on the absence of the first signal 108. The receiver circuit 104 changes the second signal 118 to the second state based on the presence of the first signal 108. In this example, the receiver circuit 104 processes the shutdown signal differently from the KA signal, so that even though the logic for processing the shutdown signal and the KA signal is different, the second signal 118 is used in the same manner. In other words, regardless of whether the first signal 108 is a shutdown signal or a KA signal, the second signal 118 operates as a PTO signal.

[0033] In another example, if at least one first signal 108 is detected, the receiver circuit 104 considers the first signal 108 to be present. To ensure detection, the transmitter circuit 116 may retransmit the first signal 108 multiple times during the first predetermined time. Conversely, if the first signal 108 is not detected during the second predetermined time, the receiver circuit 104 considers the first signal 108 to be absent.

[0034] In another example of the controller circuit 100, the first signal 108 is a power line communication (PLC) signal. In this example, the receiver circuit 104 receives the PLC signal via the DC power lines 110, 112 between the PV module 102 and the DC to AC inverter 114. In another example of the controller circuit 100, the transmitter circuit 116 transmits the first signal 108 on the DC power lines 110, 112 with a spread frequency shift keying (S-FSK) waveform that complies with the PLC protocol requirements of the SunSpec Interoperability Specification (Communication Signal for Fast Shutdown, Version 34). In another example of the controller circuit 100, the first signal 108 is a wireless communication signal. In another example of the controller circuit 100, the first signal 108 is a wired control line communication signal.

[0035] In another example of the controller circuit 100 , the second signal 118 is a digital signal having digital logic levels indicating activation of the first mode in the first state and deactivation of the first mode in the second state. In another example of the controller circuit 100 , the DC to AC inverter 114 includes a transmitter circuit 116 .

[0036] Reference Figure 2 , an example of the controller subsystem 200 includes the controller circuit 100 and the second controller circuit 202. For example, Figure 2 The second controller circuit 202 is referred to as a fast shutdown controller circuit. The example of the PV module 204 includes a first PV submodule 206 and a second PV submodule 208. The first PV submodule 206 includes a PV cell string 122. In another example, the first PV submodule 206 also includes a controller circuit 100. The controller circuit 100 receives the DC string voltage 120 from the first PV submodule 206 of the PV module 204. The controller circuit 100 includes a receiver circuit 104 and a mode control and power conversion circuit 106. The receiver circuit 104 is similar to the above referenced Figure 1 Likewise, the mode control and power conversion circuit 106 operates in the same manner as described above with reference to Figure 1 Operate in the same manner as described.

[0037] Receiver circuit 104 receives first signal 108 from RLC filter 126. For example, Figure 2The first signal 108 is referred to as a KA signal. In another example, the first signal 108 may be a shutdown signal. The receiver circuit 104 provides a second signal 118 to the second controller circuit 202 at a KA_IN node 212 via a KA_OUT node 210. The second controller circuit 202 receives a second DC string voltage 214 from a second PV cell string 216 associated with a second PV submodule 208 of the PV module 204. For example, Figure 2 A second PV submodule 208 is shown that includes a second PV cell string 216. In another example, the second PV submodule 208 also includes a second controller circuit 202. In response to the second signal 118 being changed to a second state, the second controller circuit 202 switches from the first mode to the second mode. The second controller circuit 202 converts the second DC string voltage 214 to a second backup voltage 218 in the second mode. The second controller circuit 202 provides the second backup voltage 218 to the DC power lines 110, 112 via the second output node 220 in the second mode, so that the second backup voltage 218 is connected in series with the backup voltage 124.

[0038] In one example of the PV module 204, the first signal 108 is a PLC signal, and the RLC filter 126 or any suitable filter provides the first signal 108 to the receiver circuit 104 by filtering the DC power lines 110, 112. In another example of the PV module 204, the first signal 108 is a wireless communication signal, and the receiver circuit 104 includes a wireless receiver for receiving the first signal 108 from the transmitter circuit 116 (see Figure 1 In another example of the PV module 204, the first signal 108 is a wired control line communication signal, and the receiver circuit 104 includes an input node for receiving the first signal 108 from the transmitter circuit 116 (see Figure 1 In another example, a Schottky diode 221 or any suitable bypass diode is connected from the second output node 220 of the second controller circuit 202 to the RLC filter 126 or the DC power line return portion 112. The Schottky diode 221 allows a DC current to pass when the second controller circuit 202 does not output a voltage.

[0039] In another example of the controller subsystem 200, the sum of the backup voltage 124 and the second backup voltage 218 is 2.5 volts DC or less. In yet another example of the controller subsystem 200, the sum of the backup voltage 124 and the second backup voltage 218 is 1 volt DC or less. In other examples, the sum of the backup voltage 124 and the second backup voltage 218 is any suitable DC voltage that is safe for maintenance technicians, service personnel, inspectors, and / or emergency first responders.

[0040] In another example, the controller subsystem 200 further includes a third controller circuit 222. For example, Figure 2 The third controller circuit 222 is referred to as a fast shutdown controller circuit. Another example of the PV module 204 also includes a third PV submodule 224. The third PV submodule 224 includes a third PV cell string 234. In another example, the third PV submodule 224 also includes a third controller circuit 222. In response to the receiver circuit 104 changing the second signal 118 to the second state, the second controller circuit 202 changes the third signal 226 from the first state to the second state. For example, Figure 2 The third signal 226 is referred to as a PTO signal. The second controller circuit 202 provides the third signal 226 to the third controller circuit 222 at the second KA_IN node 230 via the second KA_OUT node 228. In response to the receiver circuit 104 setting the second signal 118 to the first state, the second controller circuit 202 sets the third signal 226 to the first state. The first state of the third signal 226 is, for example, an activated state, an on state, a logic 1 state, or any suitable state indicating that normal operation of the second and third controller circuits 202, 222 is enabled. The second state of the third signal 226 is, for example, a deactivated state, an off state, a logic 0 state, or any suitable state indicating that normal operation of the second and third controller circuits 202, 222 is disabled.

[0041] The third controller circuit 222 receives the third DC string voltage 232 from the third PV cell string 234. In response to the third signal 226 being changed to the second state, the third controller circuit 222 switches from the first mode to the second mode. The third controller circuit 222 converts the third DC string voltage 232 to a third backup voltage 236 in the second mode. The third controller circuit 222 provides the third backup voltage 236 to the DC power lines 110, 112 via the third output node 238 in the second mode, so that the third backup voltage 236 is connected in series with the backup voltage 124 and the second backup voltage 218.

[0042] In one example, a Schottky diode 240 or any suitable bypass diode is connected from the third output node 238 of the third controller circuit 222 to the RLC filter 126 or the DC power line return 112. The Schottky diode 240 allows DC current to pass when the third controller circuit 222 does not output a voltage.

[0043] In another example of the controller subsystem 200, the sum of the backup voltage 124, the second backup voltage 218, and the third backup voltage 236 is 2.5 volts DC or less. In yet another example of the controller subsystem 200, the sum of the backup voltage 124, the second backup voltage 218, and the third backup voltage 236 is 1 volt DC or less. In other examples, the sum of the backup voltage 124, the second backup voltage 218, and the third backup voltage 236 is any suitable DC voltage that is safe for maintenance technicians, service personnel, inspectors, and / or emergency first responders.

[0044] Reference Figure 3 In another example of the controller circuit 100, the mode control and power conversion circuit 106 provides the operating voltage 302 based on the DC string voltage 120 to the DC power lines 110, 112 in the first mode. The standby voltage 124 is less than the operating voltage 302. The mode control and power conversion circuit 106 decouples the operating voltage 302 from the DC power lines 110, 112 in the second mode.

[0045] In another example of the controller circuit 100, the mode control and power conversion circuit 106 includes a regulator circuit (e.g., a low dropout (LDO) regulator) 304 and a switch device (S1) 306. The regulator circuit 304 receives the DC string voltage 120 and converts the DC string voltage 120 to a backup voltage 124. The switch device 306 receives the backup voltage 124 from the regulator circuit 304 at an input terminal 308, receives the second signal 118 from the receiver circuit 104 at a control terminal 310, and provides the backup voltage 124 to the DC power lines 110, 112 via an output terminal 312 in response to the second signal 118 being changed to a second state. The switch device 306 decouples the backup voltage 124 from the output terminal 312 in response to the second signal 118 being set to a first state.

[0046] Reference Figure 5 In another example of the controller circuit 100, the mode control and power conversion circuit 106 converts the DC string voltage 120 to the regulated operating voltage 502 in the first mode. The mode control and power conversion circuit 106 provides the regulated operating voltage 502 to the DC power lines 110, 112 in the first mode. The backup voltage 124 is less than the regulated operating voltage 502. The mode control and power conversion circuit 106 stops providing the regulated operating voltage 502 to the DC power lines 110, 112 in the second mode.

[0047] Continue to refer to Figure 5In another example of the controller circuit 100, the mode control and power conversion circuit 106 includes a regulator circuit (e.g., an LDO regulator) 304 and a switch device (S1) 306. The regulator circuit 304 receives the DC string voltage 120 and converts the DC string voltage 120 to a backup voltage 124. The switch device 306 receives the backup voltage 124 from the regulator circuit 304 at an input terminal 308, receives the second signal 118 from the receiver circuit 104 at a control terminal 310, and provides the backup voltage 124 to the DC power lines 110, 112 via the output terminal 312 in response to the second signal 118 being changed to a second state. The switch device 306 decouples the backup voltage 124 from the output terminal 312 in response to the second signal 118 being set to the first state.

[0048] Reference Figure 7 In another example of the controller circuit 100, the mode control and power conversion circuit 106 converts the DC string voltage 120 to the regulated operating voltage 502 in the first mode. The mode control and power conversion circuit 106 provides the regulated operating voltage 502 to the DC power lines 110, 112 in the first mode. The backup voltage 124 is less than the regulated operating voltage 502. The mode control and power conversion circuit 106 stops providing the regulated operating voltage 502 to the DC power lines 110, 112 in the second mode.

[0049] Continue to refer to Figure 7 In another example of the controller circuit 100, the mode control and power conversion circuit 106 includes a switching converter circuit 702 and a converter controller circuit 704. The switching converter circuit 702 receives the DC string voltage 120 and converts the DC string voltage 120 to the regulated operating voltage 502 in the first mode and converts the DC string voltage to the standby voltage 124 in the second mode. The converter controller circuit 704 receives the second signal 118 from the receiver circuit 104 and controls the switching converter circuit 702 by switching the switching converter circuit 702 from the first mode to the second mode in response to the second signal 118 being changed to the second state. In response to the second signal 118 being set to the first state, the converter controller circuit 704 switches the switching converter circuit 702 to the first mode.

[0050] Refer again Figure 3, an example of a PV module 102 includes a controller circuit 100, a PV cell string 122, a PLC connection 314, and a capacitor (C) 316. The controller circuit 100 includes a receiver circuit 104 and a mode control and power conversion circuit 106. The receiver circuit 104 includes a PLC receiver 318 and an OR gate 320. The mode control and power conversion circuit 106 includes a regulator circuit (e.g., an LDO regulator) 304, a first switch device (S1) 306, and a second switch device (S2) 322.

[0051] In one example, the PLC receiver 318, the OR gate 320, the regulator circuit 304, and the first switch device 306 are packaged in an IC 324. The IC 324 includes a PLC positive (PLCP) pin 326, a PLC negative (PLCN) pin 328, a voltage PV positive (VPVP) pin 330, a voltage PV negative (VPVN) pin 332, a keep alive input (KA_IN) pin 334, a keep alive output (KA_OUT) pin 336, and a voltage output (VOUT) pin 338.

[0052] The PV cell string 122 provides a DC string voltage 120 to the regulator circuit 304 via the VPVP pin 330 and provides the DC string voltage to an input terminal 340 of the second switching device 322. The DC string voltage 120 is also referred to as the operating voltage 302. A DC return path 342 from the PV cell string 122 is connected to the VPVN pin 332 of the IC 324, a negative terminal 344 of the capacitor 316, and the DC power line return portion 112. The DC power line 110 is connected to an output terminal 346 of the second switching device 322, to an output terminal 312 of the first switching device 306 via a VOUT pin 338 of the IC 324, and to a positive terminal 348 of the capacitor 316.

[0053] Although not shown, the input terminals of the PLC connection 314 are connected to the DC power lines 110, 112. The output terminals 350 of the PLC connection 314 are connected to the input terminals 352 of the PLC receiver 318 via the PLCP and PLCN pins 326, 328. In this example, the KA_IN pin 334 is connected to the first input terminal 354 of the OR gate 320 and does not receive signals from external components. The output terminal 356 of the PLC receiver 318 provides a KA PRESENT signal 358 to the second input terminal 360 of the OR gate 320. The regulator circuit 304 provides the standby voltage 124 to the input terminal 308 of the first switching device 306. In another example of the controller circuit 100, the PLC signal on the DC power lines 110, 112 is a shutdown signal instead of a KA signal, and the output terminal 356 of the PLC receiver 318 is a SHUTDOWN ABSENT signal instead of a KA PRESENT signal 358.

[0054] Continue to refer to Figure 3 During the first operating mode, the transmitter circuit 116 (eg, Figure 1 ) repeatedly transmits the first signal 108 via the DC power lines 110, 112. The PLC connection 314 acts as an RLC filter 126 (e.g., Figure 1 ) to filter the DC power lines 110, 112 and provide the first signal 108 to the PLC receiver 318 via the PLCP and PLCN pins 326, 328. The PLC receiver 318 sets the KA PRESENT signal 358 to a first state based on the presence of the first signal 108, and changes the KA PRESENT signal 358 to a second state based on the absence of the first signal 108. The first state of the KA PRESENT signal 358 is, for example, an activated state, an on state, a logic 1 state, or any suitable state indicating that normal operation of the controller circuit 100 is enabled. The second state of the KA PRESENT signal 358 is, for example, a deactivated state, an off state, a logic 0 state, or any suitable state indicating that normal operation of the controller circuit 100 is disabled. In another example of the PV module 102, the first signal 108 is a wireless communication signal, and the receiver circuit 104 includes a method for transmitting the first signal 108 from the transmitter circuit 116 (e.g., Figure 1 ) receives the first signal 108. In yet another example of the PV module 102, the first signal 108 is a wired control line communication signal, and the receiver circuit 104 includes a wireless receiver for receiving the first signal 108 from the transmitter circuit 116 (e.g., Figure 1 ) receives an input node of the first signal 108.

[0055] In this example, the output terminal 362 of the OR gate 320 (e.g., the second signal 118) simply follows the first state and the second state of the first signal 108 because there is no connection to the first input terminal 354 of the OR gate. In other words, the second signal 118 is set to the first state based on the presence of the first signal 108, and the second signal is changed to the second state based on the absence of the first signal 108. In an alternative example, the OR gate 320 receives an alternative first signal 364 at the first input terminal 354 via the KA_IN pin 334, and there is no connection to the PLCP and PLCN pins 326, 328. For example, the alternative first signal 364 is provided by another second signal (not shown) from another controller circuit (not shown) associated with the PV module 102. For additional information on the operation of multiple controller circuits in a PV module having multiple PV submodules, see Figure 2 In any respect, the second signal 118 is provided from the output terminal 362 of the OR gate to the control terminal 310 of the first switching device 306 and to the control terminal 366 of the second switching device 322 via the KA_OUT pin 336 .

[0056] In the first mode, setting the second signal 118 to the first state activates the first and second switching devices 306, 322. Activation of the first switching device 306 decouples the backup voltage 124 from the VOUT pin 338 and the DC power line 110. Activation of the second switching device 322 connects the operating voltage 302 to the DC power line 110.

[0057] In the second mode, changing the second signal 118 to the second state deactivates the first and second switching devices 306, 322. Deactivation of the first switching device 306 couples the backup voltage 124 to the DC power line 110 via the VOUT pin 338. Deactivation of the second switching device 322 decouples the operating voltage 302 from the DC power line 110.

[0058] In another example of the controller circuit 100, the first switch device 306 includes a field effect transistor (FET), a plurality of FETs, any suitable switch device, or any switch device in combination with other components forming a suitable switch device. In another example of the controller circuit 100, the second switch device 322 includes a FET, a plurality of FETs, any suitable switch device, or any switch device in combination with other components forming a suitable switch device. In another example of the controller circuit 100, the regulator circuit 304 includes an LDO regulator, any suitable voltage regulator, or any suitable voltage regulator in combination with other components forming a suitable regulator circuit.

[0059] In another example of the controller circuit 100, the IC 324 includes the second switch device 322. In another example, the IC 324 includes the PLC connection 314. In another example, the IC 324 includes the capacitor 316.

[0060] Reference Figure 4 , the timing diagram 400 shows a PV module 102 (eg, in a first mode (mode 1) 402), transitioning to a second mode (mode 2) 404 at time T1 406, and returning to the first mode (mode 1) 408 at time T2 410. Figure 3 ) Figure 3 An example of the timing of the select signals is shown.

[0061] The KA signal 412 is plotted to represent the first signal 108 (eg, Figure 3 ). The plurality of changes 414 on the plotted KA signal 412 represent the repetitive nature of the first signal 108 during the first pattern 402, 408. Between T1 406 and T2 410, the changes 414 on the plotted KA signal 412 no longer exist. This indicates that the transmitter circuit 116 (e.g., Figure 1 ) stops transmitting the first signal 108 via the DC power lines 110, 112. For example, this condition occurs when the start device 1702 (see Fig.17 ) triggers the PV module 102 in the second mode 404 (e.g., Figure 3 ) occurs after the operation.

[0062] In another example, the first signal 108 is a shutdown signal instead of a KA signal. In this alternative example, Figure 3 The controller circuit 100 switches to the second mode in response to receiving the shutdown signal (eg, rather than after detecting the absence of the KA signal). Figure 4 The shutdown signal is not shown in the timing diagram 400 of FIG. For example, the shutdown signal will occur at T1 406 and trigger the transition from the first mode (mode 1) 402 to the second mode (mode 2) 404. Another signal (e.g., a KA signal or any suitable start or enable signal) will occur at T2 410 to trigger the transition from the second mode (mode 2) 404 to the first mode (mode 1) 408.

[0063] KA PRESENT signal 416 is depicted as representing KA PRESENT signal 358 (eg, Figure 3). During the first mode 402, 408, the plotted KA PRESENT signal 416 is set to a first state based on the presence of the first signal 108. During the second mode 404, the plotted KA PRESENT signal 416 is changed to a second state based on the absence of the first signal 108. In another example, the KA PRESENT signal 108 is a SHUTDOWN ABSENT signal (not shown) that is not present (e.g., high) during the first mode (mode 1) 402, 408 and is present (e.g., low) during the second mode (mode 2) 406.

[0064] The KA_IN signal 418 is plotted to represent an alternative first signal 364 (eg, Figure 3 ).exist Figure 3 In the IC 324 of FIG. 4 , the KA_IN pin 334 is not connected. Therefore, during the first mode 402 , 408 , and the second mode 404 , the alternative first signal 363 is in a constant state (eg, logic 0).

[0065] The PTO signal 420 is plotted to represent the second signal 118 (eg, Figure 3 During the first mode 402, 408, the second signal 118 is set to the first state (e.g., logic 1) based on the KA PRESENT signal 358 being set to the first state. During the second mode 404, the second signal 118 is changed to the second state (e.g., logic 0) based on the KAPRESENT signal 358 being changed to the second state.

[0066] The plotted voltage PV positive (VPVP) signal 422 represents the DC string voltage 120 (eg, DC string voltage 120 ) provided by the PV cell string 122 to the VPVP pin 330 of the IC 324 . Figure 3 ). The DC string voltage 120 is also referred to as the operating voltage 302. Figure 4 The plotted VPVP signal 422 reflects a nominal steady-state condition with normal lighting conditions. In one example, the DC string voltage 120 varies over time based on the changing lighting conditions. The plotted VPVP signal 422 shows that the transition from the first mode 402 to the second mode 404 and back to the first mode 408 does not affect the DC string voltage 120.

[0067] The first switching device (S1) state 424 is plotted to represent the switching state (eg, input terminal 308 to output terminal 312) of the first switching device 306 (eg, Figure 3During the first mode 402, 408, the switch state is open due to the second signal 118 being set to the first state based on the activation of the first switch device 306. During the second mode 404, the switch state is closed due to the second signal 118 being changed to the second state based on the deactivation of the first switch device 306.

[0068] The second switching device (S2) state 426 is plotted to represent the switching state (eg, input terminal 340 to output terminal 346) of the second switching device 322 (eg, Figure 3 During the first mode 402, 408, the switch state is closed due to the second signal 118 being set to the first state based on the activation of the second switch device 322. During the second mode 404, the switch state is open due to the second signal 118 being changed to the second state based on the deactivation of the second switch device 322.

[0069] The voltage output (VOUT) signal 428 is plotted to represent the VOUT pin 338 (eg, Figure 3 ). The VOUT pin 338 is connected to the DC power line 110, the output terminal 346 of the second switching device 322, and the output terminal 312 of the first switching device 306. During the first mode 402, 408, the second switching device 322 provides the operating voltage 302 to the DC power line 110, and the first switching device 306 decouples the standby voltage 124 from the VOUT pin 338. In these cases, during the first mode 402, 408, the voltage at the VOUT pin 338 is the operating voltage 302. During the second mode 404, the first switching device 306 provides the standby voltage 124 to the VOUT pin 338, and the second switching device 322 decouples the operating voltage 302 from the DC power line 110. In these cases, the standby voltage 124 is provided to the DC power line 110 during the second mode 404.

[0070] Refer again Figure 5 , another example of a PV module 102 includes a controller circuit 100, a PV cell string 122, a PLC connection 314, and a capacitor (C) 316. The controller circuit 100 includes a receiver circuit 104 and a mode control and power conversion circuit 106. The receiver circuit 104 includes a PLC receiver 318 and an OR gate 320. The mode control and power conversion circuit 106 includes a regulator circuit (e.g., an LDO regulator) 304, a first switching device (S1) 306, a switching converter circuit 504, a converter controller circuit 506, and a feedback circuit 508.

[0071] In one example, the PLC receiver 318, the OR gate 320, the regulator circuit 304, the first switch device 306, and the converter controller circuit 506 are packaged in an IC 510. The IC 510 includes a PLC positive (PLCP) pin 512, a PLC negative (PLCN) pin 514, a voltage PV positive (VPVP) pin 516, a voltage PV negative (VPVN) pin 518, a keep alive input (KA_IN) pin 520, a voltage output (VOUT) pin 522, a high gate (HG) pin 524, a switch node (SW) pin 526, a low gate (LG) pin 528, a DC power ground (PGND) pin 530, and a feedback (FB) pin 532.

[0072] exist Figure 5 In the PV module 102 of FIG. 1 , the switching converter circuit 504 includes a HG FET (Q1) 534, a LG FET (Q2) 536, and an inductor (L) 538. This type of switching converter circuit 504 is also referred to as a buck converter. In other examples, the switching converter circuit 504 includes a boost converter, a buck-boost converter, a Cuk converter, or any suitable switching converter circuit.

[0073] The feedback circuit 508 includes first and second resistors 540 , 542 forming a voltage divider network. In other examples, the feedback circuit 508 includes any combination of components suitable for providing a feedback signal from the switching converter circuit 504 to the converter controller circuit 506 .

[0074] The PV cell string 122 provides the DC string voltage 120 to the regulator circuit 304 and the drain terminal 544 of the HG FET 534 via the VPVP pin 516. The DC return path 342 from the PV cell string 122 is connected to the VPVN pin 518 of the IC 510, the ground terminal 546 of the converter controller circuit 506, the PGND pin 530 of the IC 510, the source terminal 548 of the LG FET 536, the PGND node 550 of the switching converter circuit 504, the negative terminal 344 of the capacitor 316, and the DC power line return portion 112.

[0075] The DC power line 110 is connected to the output terminal 312 of the first switching device 306 via the VOUT pin 522 of the IC 510, to the output node 552 of the switching converter circuit 504, to the input terminal 554 of the feedback circuit 508, and to the positive terminal 348 of the capacitor 316. Although not shown, the input terminal of the PLC connection 314 is connected to the DC power lines 110, 112. The output terminal 350 of the PLC connection 314 is connected to the input terminal 352 of the PLC receiver 318 via the PLCP and PLCN pins 512, 514. In this example, the KA_IN pin 520 is connected to the first input terminal 354 of the OR gate 320 and does not receive signals from external components. The output terminal 356 of the PLC receiver 318 provides the KA PRESENT signal 358 to the second input terminal 360 of the OR gate 320. The regulator circuit 304 provides the backup voltage 124 to the input terminal 308 of the first switching device 306. In another example of the controller circuit 100 , the PLC signal on the DC power lines 110 , 112 is a SHUTDOWN signal instead of a KA signal, and the output terminal 356 of the PLC receiver 318 is a SHUTDOWN ABSENT signal instead of a KA PRESENT signal 358 .

[0076] During the first operating mode, the transmitter circuit 116 (eg, Figure 1 ) repeatedly transmits the first signal 108 via the DC power lines 110, 112. Figure 5 , PLC connection 314 acts as RLC filter 126 (e.g., Figure 1 ) to filter the DC power lines 110, 112 and provide the first signal 108 to the PLC receiver 318 via the PLCP and PLCN pins 512, 514. The PLC receiver 318 sets the KA PRESENT signal 358 to a first state based on the presence of the first signal 108, and changes the KA PRESENT signal 358 to a second state based on the absence of the first signal 108. The first state of the KA PRESENT signal 358 is, for example, an activated state, an on state, a logic 1 state, or any suitable state indicating that normal operation of the controller circuit 100 is enabled. The second state of the KA PRESENT signal 358 is, for example, a deactivated state, an off state, a logic 0 state, or any suitable state indicating that normal operation of the controller circuit 100 is disabled. In another example of the PV module 102, the first signal 108 is a wireless communication signal, and the receiver circuit 104 includes a wireless receiver (e.g., Figure 1In yet another example of the PV module 102, the first signal 108 is a wired control line communication signal, and the receiver circuit 104 includes a circuit for transmitting the control line communication signal from the transmitter circuit 116 (eg, Figure 1 ) receives an input node of the first signal 108.

[0077] In this example, the output terminal 362 of the OR gate 320 (e.g., the second signal 118) simply follows the first state and the second state of the first signal 108 because there is no connection to the first input terminal 354 of the OR gate. In other words, the second signal 118 is set to the first state based on the presence of the first signal 108, and the second signal is changed to the second state based on the absence of the first signal 108. In an alternative example, the OR gate 320 receives an alternative first signal 364 at the first input terminal 354 via the KA_IN pin 520, and there is no connection to the PLCP and PLCN pins 512, 514. For example, the alternative first signal 364 is provided by another second signal (not shown) from another controller circuit (not shown) associated with the PV module 102. For additional information on the operation of multiple controller circuits in a PV module having multiple PV submodules, see Figure 2 In any respect, the second signal 118 is provided from the output terminal 362 of the OR gate to the control terminal 310 of the first switching device 306 and the mode selection terminal 556 of the converter controller circuit 506 .

[0078] In the first mode, setting the second signal 118 to the first state activates the first switching device 306 and selects operation of the converter controller circuit 506 based on a first reference voltage (VREF1) 558 associated with the regulated operating voltage 502. Activation of the first switching device 306 decouples the backup voltage 124 from the VOUT pin 522 and the DC power line 110. Operation of the converter controller circuit 506 based on VREF1 558 causes the switching converter circuit 504 to provide the regulated output voltage 502 to the DC power line 110 via the output node 552.

[0079] In the second mode, changing the second signal 118 to the second state deactivates the first switching device 306 and deselects the operation of the converter controller circuit 506. The deactivation of the first switching device 306 couples the backup voltage 124 to the DC power line 110 via the VOUT pin 522. The deselection operation of the converter controller circuit 506 causes the switching converter circuit to stop providing the regulated operating voltage 302 to the DC power line 110.

[0080] Further references Figure 5, the switching converter circuit 504 is controlled by the converter control circuit 506 in the first mode based on VREF1 558. The HG FET 534 is coupled between the DC string voltage 120 and the SW node 560 of the switching converter circuit 504. The LGFET 536 is coupled between the SW node 560 and the DC power line return portion 112. The first resistor and the second resistor 540, 542 of the feedback circuit 508 are connected in series with each other between the output node 552 of the switching converter circuit 504 and ground to provide a feedback signal 562 to the feedback terminal 564 of the converter controller circuit 506 via the FB pin 532 of the IC 510. The inductor 538 is coupled between the output node 552 and the switching node 560. The converter controller circuit 506 provides pulse width modulated switch control signals (e.g., HG and LG signals 565, 566) to selectively activate and deactivate the HG FET 534 and the LG FET 536 in a complementary manner to control the regulated operating voltage 502 at the output node 552. The converter controller circuit 506 varies the pulse width of the HG and LG signals 565, 566 based on the feedback signal 562 and VREF1 558.

[0081] In another example of the controller circuit 100, the first switch device 306 includes a FET, a plurality of FETs, any suitable switch device, or any switch device in combination with other components forming a suitable switch device. In another example of the controller circuit 100, the second switch device 322 includes a FET, a plurality of FETs, any suitable switch device, or any switch device in combination with other components forming a suitable switch device. In another example of the controller circuit 100, the regulator circuit 304 includes an LDO regulator, any suitable voltage regulator, or any suitable voltage regulator in combination with other components forming a suitable regulator circuit.

[0082] In another example of the controller circuit 100, the IC 510 includes the switching converter circuit 504. In another example, the IC 510 includes the PLC connection 314. In another example, the IC 510 includes the capacitor 316.

[0083] Reference Figure 6 , the timing diagram 600 shows a PV module 102 (eg, in a first mode (mode 1) 602), transitioning to a second mode (mode 2) 604 at time T1 606, and returning to the first mode (mode 1) 608 at time T2 610. Figure 5 ) Figure 5 An example of the timing of the select signals is shown.

[0084] The KA signal 612 is plotted to represent the first signal 108 (eg, Figure 5 ). The plurality of changes 614 on the plotted KA signal 612 represent the repetitive nature of the first signal 108 during the first pattern 602, 608. Between T1 606 and T2 610, the changes 614 on the plotted KA signal 612 no longer exist. This indicates that the transmitter circuit 116 (e.g., Figure 1 ) stops transmitting the first signal 108 via the DC power lines 110, 112. For example, this condition occurs when the start device 1702 (see Fig.17 ) triggers the PV module 102 in the second mode 604 (e.g., Figure 5 ) occurs after the operation.

[0085] In another example, the first signal 108 is a shutdown signal instead of a KA signal. In this alternative example, Figure 5 The controller circuit 100 switches to the second mode in response to receiving the shutdown signal (eg, rather than after detecting the absence of the KA signal). Figure 6 The shutdown signal is not shown in the timing diagram 600. For example, the shutdown signal will occur at T1 606 and trigger the transition from the first mode (mode 1) 602 to the second mode (mode 2) 604. Another signal (e.g., a KA signal or any suitable start or enable signal) will occur at T2 610 to trigger the transition from the second mode (mode 2) 604 to the first mode (mode 1) 608.

[0086] KA PRESENT signal 616 is depicted as representing KA PRESENT signal 358 (eg, Figure 5 ). During the first mode 602, 608, the plotted KA PRESENT signal 616 is set to a first state based on the presence of the first signal 108. During the second mode 604, the plotted KA PRESENT signal 616 is changed to a second state based on the absence of the first signal 108. In another example, the KA PRESENT signal 108 is a SHUTDOWN ABSENT signal (not shown) that is not present (e.g., high) during the first mode (mode 1) 602, 608 and is present (e.g., low) during the second mode (mode 2) 604.

[0087] The KA_IN signal 618 is plotted to represent the alternative first signal 364 (eg, Figure 5 ).exist Figure 5In the IC 510 of FIG. 5A , the KA_IN pin 520 is not connected. Therefore, during the first mode 602 , 608 , and the second mode 604 , the replacement first signal 363 is in a constant state (eg, logic 0).

[0088] The PTO signal 620 is plotted to represent the second signal 118 (eg, Figure 5 During the first mode 602, 608, the second signal 118 is set to the first state (e.g., logic 1) based on the KA PRESENT signal 358 being set to the first state. During the second mode 604, the second signal 118 is changed to the second state (e.g., logic 0) based on the KAPRESENT signal 358 being changed to the second state.

[0089] The voltage PV positive (VPVP) signal 622 is plotted to represent the DC string voltage 120 (eg, VPVP) provided by the PV cell string 122 to the VPVP pin 516 of the IC 510. Figure 5 ). The DC string voltage 120 is also provided to the drain terminal 544 of the HG FET 534 in the switching converter circuit 504. Figure 6 The plotted VPVP signal 622 reflects a nominal steady-state condition with normal lighting conditions. In one example, the DC string voltage 120 varies over time based on the changing lighting conditions. The plotted VPVP signal 422 shows that the transition from the first mode 602 to the second mode 604 and back to the first mode 608 does not affect the DC string voltage 120.

[0090] The first switching device (S1) state 624 is plotted to represent the switching state (eg, input terminal 308 to output terminal 312) of the first switching device 306 (eg, Figure 5 During the first mode 602, 608, the switch state is open due to the second signal 118 being set to the first state based on the activation of the first switch device 606. During the second mode 604, the switch state is closed due to the second signal 118 being changed to the second state based on the deactivation of the first switch device 306.

[0091] The HG FET (Q1) state 626 is plotted to represent the switching state (eg, drain terminal 544 to source terminal 568) of the HG FET 534 (eg, Figure 5). During the first mode 602, 608, since the second signal 118 is set to the first state, the switch state switches between the "on" and "off" states based on the pulse width modulated switch control signal (e.g., HG signal 565) applied by the converter controller circuit 506 to the gate terminal 570 of the HG FET 534. During the second mode 604, since the second signal 118 is changed to the second state, the switch state remains off based on the deactivation of the HG FET 534 by the converter controller circuit 506.

[0092] The LG FET (Q2) state 627 is plotted to represent the switching state of the LG FET 536 (eg, drain terminal 572 to source terminal 548) (eg, Figure 5 ). During the first mode 602, 608, since the second signal 118 is set to the first state, the switch state switches between the "off" and "on" states based on the pulse width modulated switch control signal (e.g., LG signal 566) applied by the converter controller circuit 506 to the gate terminal 574 of the LG FET 536. During the second mode 604, since the second signal 118 is changed to the second state, the switch state remains off based on the deactivation of the LG FET 536 by the converter controller circuit 506.

[0093] The voltage output (VOUT) signal 628 is plotted to represent the output node 552 (eg, Figure 5 ). The output node 552 is connected to the DC power line 110. During the first mode 602, 608, the switching converter circuit 504 provides the regulated operating voltage 502 to the DC power line 110 via the output node 552, and the first switching device 306 decouples the standby voltage 124 from the VOUT pin 522. In these cases, during the first mode 602, 608, the voltage at the VOUT pin 522 is the regulated operating voltage 502. During the second mode 604, the first switching device 306 provides the standby voltage 124 to the VOUT pin 522, and the switching converter circuit 504 decouples the regulated operating voltage 502 from the DC power line 110. In these cases, the standby voltage 124 is provided to the DC power line 110 during the second mode 604.

[0094] Refer again Figure 7, another example of a PV module 102 includes a controller circuit 100, a PV cell string 122, a PLC connection 314, and a capacitor (C) 316. The controller circuit 100 includes a receiver circuit 104 and a mode control and power conversion circuit 106. The receiver circuit 104 includes a PLC receiver 318 and an OR gate 320. The mode control and power conversion circuit 106 includes a switching converter circuit 702, a converter controller circuit 704, and a feedback circuit 508.

[0095] In one example, the PLC receiver 318, the OR gate 320, and the converter controller circuit 704 are packaged in an IC 706. The IC 706 includes a PLC positive (PLCP) pin 708, a PLC negative (PLCN) pin 710, a voltage PV negative (VPVN) pin 712, a keep alive input (KA_IN) pin 714, a high gate (HG) pin 716, a switch node (SW) pin 718, a low gate (LG) pin 720, a DC power ground (PGND) pin 722, and a feedback (FB) pin 724.

[0096] exist Figure 7 In the PV module 102 of FIG. 1 , the switching converter circuit 702 includes a HG FET (Q1) 534, a LG FET (Q2) 536, and an inductor (L) 538. This type of switching converter circuit 702 is also referred to as a buck converter. In other examples, the switching converter circuit 702 includes a boost converter, a buck-boost converter, a Cuk converter, or any suitable switching converter circuit.

[0097] The feedback circuit 508 includes first and second resistors 540 , 542 forming a voltage divider network. In other examples, the feedback circuit 508 includes any combination of components suitable for providing a feedback signal from the switching converter circuit 702 to the converter controller circuit 704 .

[0098] The PV cell string 122 provides the DC string voltage 120 to the drain terminal 544 of the HG FET 534. The DC return path 342 from the PV cell string 122 is connected to the VPVN pin 712 of the IC 706, the ground terminal 546 of the converter controller circuit 704, the PGND pin 722 of the IC 706, the source terminal 548 of the LG FET 536, the PGND node 550 of the switching converter circuit 702, the negative terminal 344 of the capacitor 316, and the DC power line return portion 112.

[0099] The DC power line 110 is connected to the output node 552 of the switching converter circuit 702, the input terminal 554 of the feedback circuit 508, and the positive terminal 348 of the capacitor 316. Although not shown, the input terminal of the PLC connection 314 is connected to the DC power lines 110, 112. The output terminal 350 of the PLC connection 314 is connected to the input terminal 352 of the PLC receiver 318 via the PLCP and PLCN pins 708, 710. In this example, the KA_IN pin 714 is connected to the first input terminal 354 of the OR gate 320 and does not receive signals from external components. The output terminal 356 of the PLC receiver 318 provides the KA PRESENT signal 358 to the second input terminal 360 of the OR gate 320. In another example of the controller circuit 100, the PLC signal on the DC power lines 110, 112 is a shutdown signal instead of a KA signal, and the output terminal 356 of the PLC receiver 318 is a SHUTDOWN ABSENT signal instead of a KAPRESENT signal 358.

[0100] During the first operating mode, the transmitter circuit 116 (eg, Figure 1 ) repeatedly transmits the first signal 108 via the DC power lines 110, 112. Figure 7 , PLC connection 314 acts as RLC filter 126 (e.g., Figure 1 ) to filter the DC power lines 110, 112 and provide the first signal 108 to the PLC receiver 318 via the PLCP and PLCN pins 708, 710. The PLC receiver 318 sets the KA PRESENT signal 358 to a first state based on the presence of the first signal 108, and changes the KA PRESENT signal 358 to a second state based on the absence of the first signal 108. The first state of the KA PRESENT signal 358 is, for example, an activated state, an on state, a logic 1 state, or any suitable state indicating that normal operation of the controller circuit 100 is enabled. The second state of the KA PRESENT signal 358 is, for example, a deactivated state, an off state, a logic 0 state, or any suitable state indicating that normal operation of the controller circuit 100 is disabled. In another example of the PV module 102, the first signal 108 is a wireless communication signal, and the receiver circuit 104 includes a method for transmitting the first signal 108 from the transmitter circuit 116 (e.g., Figure 1 ) receives the first signal 108. In yet another example of the PV module 102, the first signal 108 is a wired control line communication signal, and the receiver circuit 104 includes a wireless receiver for receiving the first signal 108 from the transmitter circuit 116 (e.g., Figure 1 ) receives an input node of the first signal 108.

[0101] In this example, the output terminal 362 of the OR gate 320 (e.g., the second signal 118) simply follows the first state and the second state of the first signal 108 because there is no connection to the first input terminal 354 of the OR gate. In other words, the second signal 118 is set to the first state based on the presence of the first signal 108, and the second signal is changed to the second state based on the absence of the first signal 108. In an alternative example, the OR gate 320 receives an alternative first signal 364 at the first input terminal 354 via the KA_IN pin 714, and there is no connection to the PLCP and PLCN pins 708, 710. For example, the alternative first signal 364 is provided by another second signal (not shown) from another controller circuit (not shown) associated with the PV module 102. For additional information on the operation of multiple controller circuits in a PV module having multiple PV submodules, see Figure 2 In any respect, the second signal 118 is provided from the output terminal 362 of the OR gate to the mode selection terminal 556 of the converter controller circuit 704 .

[0102] In the first mode, setting the second signal 118 to the first state selects operation of the converter controller circuit 704 based on a first reference voltage (VREF1) 558 associated with the regulated operating voltage 502. Operation of the converter controller circuit 704 based on VREF1 558 causes the switching converter circuit 702 to provide the regulated output voltage 502 to the DC power line 110 via the output node 552. Operation of the converter controller circuit 704 based on VREF1 558 also causes the switching converter circuit 702 to stop providing the backup voltage 124 to the output node 552.

[0103] In the second mode, changing the second signal 118 to the second state selects operation of the converter controller circuit 704 based on a second reference voltage (VREF2) 726 associated with the backup voltage 124. Operation of the converter controller circuit 704 based on VREF2 726 causes the switching converter circuit 702 to provide the backup voltage 124 to the DC power line 110 via the output node 552. Operation of the converter controller circuit 704 based on VREF2 726 also causes the switching converter circuit 702 to stop providing the regulated operating voltage 502 to the output node 552.

[0104] Further references Figure 7, the switching converter circuit 702 is controlled by the converter control circuit 704 in the first mode based on VREF1 558. The HG FET 534 is coupled between the DC string voltage 120 and the SW node 560 of the switching converter circuit 702. The LGFET 536 is coupled between the SW node 560 and the DC power line return portion 112. The first resistor and the second resistor 540, 542 of the feedback circuit 508 are connected in series with each other between the output node 552 of the switching converter circuit 702 and ground to provide a feedback signal 562 to the feedback terminal 564 of the converter controller circuit 704 via the FB pin 724 of the IC 706. The inductor 538 is coupled between the output node 552 and the switching node 560. The converter controller circuit 704 provides pulse width modulated switch control signals (e.g., HG and LG signals 565, 566) to selectively activate and deactivate the HG FET 534 and the LG FET 536 in a complementary manner to control the regulated operating voltage 502 at the output node 552. The converter controller circuit 704 varies the pulse width of the HG and LG signals 565, 566 based on the feedback signal 562 and VREF1 558.

[0105] In this example, the switching converter circuit 702 is also controlled by the converter control circuit 704 in the second mode. However, in the second mode, the control is based on VREF2 726. The converter controller circuit 704 provides pulse width modulated switching control signals (e.g., HG and LG signals 565, 566) to selectively activate and deactivate the HG FET 534 and the LG FET 536 in a complementary manner to control the standby voltage 124 at the output node 552. The conversion controller circuit 704 changes the pulse width of the HG and LG signals 565, 566 based on the feedback signal 562 and VREF2 726.

[0106] In another example of the controller circuit 100, the IC 706 includes the switching converter circuit 702. In another example, the IC 706 includes the PLC connection 314. In another example, the IC 706 includes the capacitor 316.

[0107] Reference Figure 8 , timing diagram 800 illustrates a PV module 102 (eg, in a first mode (mode 1) 802), transitioning to a second mode (mode 2) 804 at time T1 806, and returning to the first mode (mode 1) 808 at time T2 810. Figure 7 ) Figure 7 An example of the timing of the select signals is shown.

[0108] The KA signal 812 is plotted to represent the first signal 108 (eg, Figure 7 ). The plurality of changes 814 on the plotted KA signal 812 represent the repetitive nature of the first signal 108 during the first pattern 802, 808. Between T1 806 and T2 810, the changes 814 on the plotted KA signal 812 no longer exist. This indicates that the transmitter circuit 116 (e.g., Figure 1 ) stops transmitting the first signal 108 via the DC power lines 110, 112. For example, this condition occurs when the start device 1702 (see Fig.17 ) triggers the PV module 102 in the second mode 804 (e.g., Figure 7 ) occurs after the operation.

[0109] In another example, the first signal 108 is a shutdown signal instead of a KA signal. In this alternative example, Figure 5 The controller circuit 100 switches to the second mode in response to receiving the shutdown signal (eg, rather than after detecting the absence of the KA signal). Figure 6 The shutdown signal is not shown in the timing diagram 600. For example, the shutdown signal will occur at T1 606 and trigger the transition from the first mode (mode 1) 602 to the second mode (mode 2) 604. Another signal (e.g., a KA signal or any suitable start or enable signal) will occur at T2 610 to trigger the transition from the second mode (mode 2) 604 to the first mode (mode 1) 608.

[0110] KA PRESENT signal 816 is depicted as representing KA PRESENT signal 358 (eg, Figure 7 ). During the first mode 802, 808, the plotted KA PRESENT signal 816 is set to a first state based on the presence of the first signal 108. During the second mode 804, the plotted KA PRESENT signal 816 is changed to a second state based on the absence of the first signal 108. In another example, the KA PRESENT signal 108 is a SHUTDOWN ABSENT signal (not shown) that is not present (e.g., high) during the first mode (mode 1) 602, 608 and is present (e.g., low) during the second mode (mode 2) 604.

[0111] The KA_IN signal 618 is plotted to represent an alternative first signal 364 (eg, Figure 7 ).exist Figure 7In the IC 706 of FIG. 704 , the KA_IN pin 714 is not connected. Therefore, during the first mode 602 , 608 , and the second mode 604 , the alternative first signal 363 is in a constant state (eg, logic 0).

[0112] The PTO signal 820 is plotted to represent the second signal 118 (eg, Figure 7 During the first mode 802, 808, the second signal 118 is set to the first state (e.g., logic 1) based on the KA PRESENT signal 358 being set to the first state. During the second mode 804, the second signal 118 is changed to the second state (e.g., logic 0) based on the KA PRESENT signal 358 being changed to the second state.

[0113] The plotted DC string voltage 822 represents the DC string voltage 120 (eg, DC string voltage 120 ) provided by the PV cell string 122 to the drain terminal 544 of the HG FET 534 in the switching converter circuit 702 . Figure 7 ). Figure 8 The plotted DC string voltage 822 reflects a nominal steady-state condition with normal lighting conditions. In one example, the DC string voltage 120 varies over time based on changing lighting conditions. The plotted DC string voltage 822 shows that the transition from the first mode 802 to the second mode 804 and back to the first mode 808 does not affect the DC string voltage 120.

[0114] The HG FET (Q1) state 826 depicted represents the switching state (eg, drain terminal 544 to source terminal 568) of the HG FET 534 (eg, Figure 7 ). During the first mode 802, 808, since the second signal 118 is set to the first state, the switch state switches between the "on" and "off" states based on the pulse width modulated switch control signal associated with VREF1 558 (e.g., HG signal 565) applied by the converter controller circuit 704 to the gate terminal 570 of the HG FET 534. During the second mode 804, since the second signal 118 is changed to the second state, the switch state switches between the "on" and "off" states based on the pulse width modulated switch control signal associated with VREF2 726 (e.g., HG signal 565) applied by the converter controller circuit 704 to the gate terminal 570 of the HG FET 534.

[0115] The LG FET (Q2) state 827 is plotted to represent the switching state of the LG FET 536 (eg, drain terminal 572 to source terminal 548) (eg, Figure 7). During the first mode 802, 808, since the second signal 118 is set to the first state, the switch state switches between the "off" and "on" states based on the pulse width modulated switch control signal associated with VREF1 558 (e.g., LG signal 566) applied to the gate terminal 574 of the LG FET 536 by the converter controller circuit 704. During the second mode 804, since the second signal 118 is changed to the second state, the switch state switches between the "on" and "off" states based on the pulse width modulated switch control signal associated with VREF2 726 (e.g., LG signal 566) applied to the gate terminal 574 of the LG FET 536 by the converter controller circuit 704.

[0116] The output node signal 828 is plotted to represent the output node 552 (eg, Figure 7 ). Output node 552 is connected to DC power line 110. During first mode 802, 808, switching converter circuit 702 provides regulated operating voltage 502 to DC power line 110 via output node 552, and stops providing backup voltage 124 to output node 552. In these cases, during first mode 802, 808, the voltage at output node 552 is regulated operating voltage 502. During second mode 804, switching converter circuit 702 provides backup voltage 124 to DC power line 110 via output node 552, and switching converter circuit 702 stops providing regulated operating voltage 502 to output node 552. In these cases, backup voltage 124 is provided to DC power line 110 during second mode 804.

[0117] Reference Fig. 9 , which helps to quickly shut down the PV module 102 (e.g., Figure 1) is an example of an IC 900 of a PLC receiver 902. In this example, the IC 900 includes a PLC receiver 902, a PWM multiplexing and logic circuit 904, a high-side driver 906, a low-side driver 908, and a bias and LDO circuit 910. The IC 900 also includes a crystal oscillator 912 for supporting the operation of the PLC receiver 902. The IC 900 includes an error amplifier 914, a 1-MHz oscillator 916, a ramp generator 918, a first PWM comparator 920, an SR flip-flop 922, an MPPT circuit 924, a second PWM comparator 926, a hysteresis window generator circuit 928, a third PWM comparator 930, an on / off time limiter circuit 932, a mode control 934, and a charge pump 936 to support the operation of the PWM multiplexing and logic circuit 904. The IC 900 also includes a buffer 938, an OR gate 940, and a diode 942. IC 900 includes a VMAX pin 944, a FB pin 946, a COMP pin 948, an XTAL_IN pin 950, a PLC_P pin 952, a PLC_M pin 954, a KA_IN pin 956, a VPV_M pin 958, a KA_OUT pin 960, a VPV_P_FLT pin 962, a VPV_P pin 964, a Boot pin 966, a HG pin 968, a SW pin 970, a LG pin 972 and a PGND pin 974.

[0118] The VMAX pin 944 is an input pin connected to the input of the mode control 934. The FB pin 946 is an input pin connected to the input of the error amplifier 914. The COMP pin 948 is an output pin connected to the output of the error amplifier 914. The XTAL_IN pin 950 is an input pin connected to the input of the crystal oscillator 912. The PLC_P and PLC_M pins 952, 954 are input pins connected to the input of the PLC receiver 902. The KA_IN pin 956 is an input pin connected to the input of the buffer 938. The VPV_M and VPV_P pins 958, 964 are input pins that provide source nodes for the negative PV connection and the positive PV connection. The KA_OUT pin 960 is an output pin connected to the output of the OR gate 940. The VPV_P_FLT pin 962 is an input pin that provides a filtered source node for the positive PV connection. The Boot pin 966 is an input pin that supplies power to the high-side gate driver 906. The HG pin 968 is an output pin connected to the output of the high-side gate driver 906. SW pin 970 is an output pin connected to the high side gate driver 906 and provides a switching node for the buck converter. LG pin 972 is an output pin connected to the output of the low side gate driver 908. PGND pin 974 is an input pin that provides ground to the low side gate driver 908.

[0119] IC 900 operates as a power conversion controller that adds functionality to a PV module junction box. In other words, IC 900 is part of a remotely operated buck controller circuit card assembly in a PV module junction box. The circuit card assembly replaces the bypass diodes in PV modules deployed in a rooftop PV array. Remote control is achieved via an onboard PLC receiver 902. The PLC protocol complies with standards developed through the SunSpec Alliance. The control algorithm of IC 900 complies with the rapid shutdown requirements of NEC 690.12. In normal operation, IC 900 increases energy collection under any sunlight and load conditions.

[0120] When the PLC receiver 902 determines that the KA signal is not present, the IC 900 couples a 0.33V standby voltage to the DC power line and decouples the regulated operating voltage. The standby voltage provides a safe NEC-compliant shutdown voltage even when stacked multiple times to assist PV installers in larger rooftop systems where multiple PV strings are routed through a common conduit.

[0121] When the PLC receiver 902 determines that a KA signal is present, the IC 900 increases the buck output power under the constraint that the output voltage does not exceed the user defined voltage set by the VMAX pin 944. The maximum power tracking performance is fast enough not to interfere with the MPPT operation of the power inverter connected to the DC power line downstream of the PV module.

[0122] When the string current ISTR is below the module maximum power current, IC 900 regulates the buck output voltage to a level VMAX defined by an external resistor divider. As ISTR increases, the DC string voltage (e.g., VPV_P 964 to VPV_M 958) decreases, and IC 900 increases the buck duty cycle to maintain the VMAX output voltage, thereby reaching D=1 when ISTR reaches a level at which the DC string voltage drops to VMAX. During this mode of operation, the buck converter operates a voltage mode control loop at a fixed frequency to regulate the output voltage, which loop consists of an error amplifier 914, a ramp generator 918, and a first PWM comparator 920. The error amplifier 914 is compensated externally via the COMP pin 948.

[0123] When ISTR exceeds the maximum power current IMP, the control algorithm of IC 900 reduces the buck duty cycle to increase the output power harvest, regulating VMP and IMP at the DC string voltage (buck input). IC 900 constantly searches for maximum power harvest, tracking changes in sunlight or load current conditions. During this operating mode, the buck converter operates a window hysteresis control loop at a fixed frequency to regulate the DC string voltage to a regulated operating voltage.

[0124] IC 900 has an integrated bootstrap regulator and requires a small ceramic capacitor between the BOOT (bootstrap) pin 966 and the SW pin 970 to provide the gate drive voltage for the high-side MOSFET of the buck converter. The value of the ceramic capacitor is 0.1 μF. A ceramic capacitor with X7R or X5R class dielectric and a recommended rated voltage of 10 V or higher is recommended because of its stable characteristics over the temperature and voltage ranges. Additionally, the on-board integrated charge pump 936 supplements the charge delivered from the switching operation and allows the IC 900 to operate at 100% duty cycle.

[0125] The reference voltage system generates an accurate ±1% reference voltage over the temperature range by scaling the output of the temperature-stable bandgap circuit. The bandgap and scaling circuits generate 1.20 V at the non-inverting input of the error amplifier 914.

[0126] A resistive voltage divider between the output node of the buck converter and Vmax to the VPV_M pin 958 sets the value at which the output voltage of the buck converter is limited. The voltage at Vmax is compared with the on-board reference voltage of 1.20 V. If Vmax is higher than this threshold, the converter operates in output limit mode. If Vmax is lower than this threshold, the converter operates in MPPT mode.

[0127] Regarding the fast shutdown and PLC receiver 902, S-FSK is a modulation and demodulation technique that incorporates some of the advantages of classical spread-spectrum systems, namely resistance to narrowband interference, as well as the advantages of classical FSK systems, low complexity, and previous spread-spectrum implementations.

[0128] The transmitter assigns the space frequency fS to "data 0" and the marker frequency fM to "data 1". The difference between S-FSK and classical FSK is the fact that the positions of fS and fM are far apart from each other (spread) to improve the transmission quality. Each frequency has its own attenuation factor and local narrowband noise spectrum.

[0129] The PLC receiver 902 performs FSK demodulation at two possible frequencies (half channels), resulting in two demodulated digital signals dS and dM. If the average received quality of the two half channels is similar, the decision unit in the PLC receiver 902 determines the higher of the two demodulated channels (data 0 if ds > dm; data 1 if ds < dm). However, if the average received quality of one half channel is better than that of the other half channel, the decision unit compares the demodulated signal of the better channel with a threshold T, thus ignoring the poorer channel.

[0130] With respect to the PLC protocol, the "keep alive" signal consists of a 15-bit packet repeated approximately 10 times per second. A tone representing each bit in the sequence is transmitted for approximately 5 milliseconds. The 15-bit sequence increases the SNR (signal to noise ratio) when the SNR is limited by white additive noise. Three consecutive 15-bit keep alive sequences are combined in the detector of the PLC receiver 902 to obtain an additive signal to noise ratio.

[0131] The IC 900 is stacked to accommodate various sizes of PV modules (e.g., PV modules with multiple submodules). It is not necessary to couple the PLC signal to each IC associated with a PV module. Instead, the KA_IN and KA_OUT pins 956, 960 are used to daisy-chain the ICs so that strings of PV submodules within a PV module are turned on or off simultaneously.

[0132] PWM multiplexing and logic circuit 904 is coupled with OR gate 940, responsive to the PTO signal from PLC receiver 902 or from KA_IN pin 956. Likewise, the voltage on KA_OUT pin 960 is coupled with OR gate 940, following the state of PLC receiver 902 or KA_IN pin 956.

[0133] IC 900 has an integrated UVLO circuit that monitors the voltage on VPV_P pin 964. When VPV_P pin 964 is below 5v relative to VPV_M pin 958, the power stage is high Z and IC 900 does not convert power. When VPV_P pin 964 crosses 8 volts, power conversion begins.

[0134] Reference Fig.10 , describes a method for rapidly shutting down a PV module 102 (e.g., Figure 1 ) method 1000. In some examples, Figure 1-9 The controller circuit 100 described in embodies the method 1000. Fig.10 , method 1000 begins at 1002, where a receiver circuit 104 (eg, Figure 1 ) receives a first signal 108 from a transmitter circuit 116 associated with a PV module 102. Fig.10 At 1004, the receiver circuit 104 (eg, Figure 1 ) changes the second signal 118 from the first state to the second state based on the first signal 108. At 1006, the mode control and power conversion circuit 106 (eg, Figure 1 ) receives a DC string voltage 120 from a PV cell string 122 associated with the PV module 102. At 1008, the mode control and power conversion circuit 106 (e.g., Figure 1) receives the second signal 118 from the receiver circuit 104. At 1010, the mode control and power conversion circuit 106 (eg, Figure 1 ) switches from the first mode to the second mode in response to the second signal 118 being changed to the second state. At 1012, the mode control and power conversion circuit 106 (e.g., Figure 1 ) converts the DC string voltage 120 to the backup voltage 124 in the second mode. At 1014, the mode control and power conversion circuit 106 (e.g., Figure 1 ) in a second mode provides a backup voltage 124 to the DC power lines 110, 112 between the PV module 102 and the DC to AC inverter 114.

[0135] In another example of method 1000, the first signal 108 is a PLC signal. In this example, the receiver circuit 104 receives the PLC signal via the DC power lines 110, 112 between the PV module 102 and the DC to AC inverter 114. In another example of method 1000, the transmitter circuit 116 transmits the first signal 108 on the DC power lines 110, 112 in an S-FSK waveform that complies with the PLC protocol requirements of the SunSpec interoperability specification (communication signals for fast shutdown, version 34). In another example of the controller circuit 100, the first signal 108 is a wireless communication signal. In another example of the controller circuit 100, the first signal 108 is a wired control line communication signal. In another example of method 1000, the second signal 118 is a digital signal having a digital logic level that represents activation of the first mode in the first state and deactivation of the first mode in the second state.

[0136] Reference Fig.10 and 11 , another example of method 1000 continues from 1014 to 1102. In this example, the controller circuit 100 (e.g., Figure 2 ) receives a DC string voltage from a first PV submodule 206 of the PV module 204. The first PV submodule 206 includes a PV cell string 122. The mode control and power conversion circuit 106 receives the DC string voltage 120 from the first PV submodule 206. Fig.11 At 1102, the receiver circuit 104 (eg, Figure 2 ) provides the second signal 118 to the second controller circuit 202. Fig.11 At 1104, the second controller circuit 202 (eg, Figure 2 ) receives a second DC string voltage 214 from a second PV cell string 216 associated with a second PV submodule 208 of PV module 204. Fig.11At 1106, the second controller circuit 202 (eg, Figure 2 ) switches from the first mode to the second mode in response to the second signal 118 being changed to the second state. Fig.11 At 1108, the second controller circuit 202 (eg, Figure 2 ) converts the second DC string voltage 214 to a second standby voltage 218 in the second mode. Fig.11 At 1110 , the second controller circuit 202 provides the second backup voltage 218 to the DC power lines 110 , 112 in the second mode such that the second backup voltage 218 is connected in series with the backup voltage 124 .

[0137] Reference Figure 10-12 Another example of method 1000 continues from 1110 to 1202, where in response to the receiver circuit 108 changing the second signal 118 to a second state, the second controller circuit 202 (eg, Figure 2 ) changes the third signal 226 from the first state to the second state. Fig.12 At 1204, the second controller circuit 202 (eg, Figure 2 ) provides the third signal 226 to the third controller circuit 222. Fig.12 At 1206, the third controller circuit 222 (eg, Figure 2 ) receives a third DC string voltage 232 from a third PV cell string 234 associated with a third PV submodule 224 of PV module 204. Fig.12 At 1208, the third controller circuit 222 (eg, Figure 2 ) switches from the first mode to the second mode in response to the third signal 226 being changed to the second state. Fig.12 At 1210, the third controller circuit 222 (eg, Figure 2 ) in the second mode, converting the third DC string voltage 232 to a third standby voltage 236. Fig.12 At 1212, the third controller circuit 222 (eg, Figure 2 ) In the second mode, the third backup voltage 236 is provided to the DC power lines 110, 112, so that the third backup voltage 236 is connected in series with the backup voltage 124 and the second backup voltage 218.

[0138] Reference Fig.10 and 13 Another example of method 1000 continues from 1014 to 1302, where the mode control and power conversion circuit 106 (eg, Figure 3 ) provides an operating voltage 302 to the DC power lines 110, 112 based on the DC string voltage 120 in the first mode. The backup voltage 124 is less than the operating voltage 302. Fig.13At 1304, the mode control and power conversion circuit 106 (eg, Figure 3 ) decouples the operating voltage from the DC power line in the second mode.

[0139] Reference Fig.10 and 14 , another example of method 1000 continues from 1014 to 1402. In this example, the mode control and power conversion circuit 106 (e.g., Figure 3 ) includes a regulator circuit (eg, an LDO regulator) 304 and a switching device (S1) 306. Fig.14 At 1402, the regulator circuit 304 (eg, Figure 3 ) receives a DC string voltage 120. Fig.14 At 1404, the regulator circuit 304 (eg, Figure 3 ) converts the DC string voltage 120 to a standby voltage 124. Fig.14 At 1406, the switch device 306 (eg, Figure 3 ) receives the backup voltage 124 from the regulator circuit 304 at the input terminal 308. Fig.14 At 1408, the switch device 306 (eg, Figure 3 ) receives the second signal 118 from the receiver circuit 104 at the control terminal 310. Fig.14 At 1410, a switch device (e.g., Figure 3 ) provides the backup voltage 124 to the DC power lines 110, 112 via the output terminal 312 in response to the second signal 118 being changed to the second state. Fig.14 At 1412, a switch device (e.g., Figure 3 ) decouples the standby voltage 124 from the output terminal 312 in response to the second signal 118 being set to the first state.

[0140] Reference Fig.10 and 15 , another example of method 1000 continues from 1014 to 1502, where the mode control and power conversion circuit 106 (eg, Figure 7 ) in the first mode converts the DC string voltage 120 to a regulated operating voltage 502. The standby voltage 124 is less than the regulated operating voltage 502. Fig.15 At 1504, the mode control and power conversion circuit 106 (eg, Figure 7 ) provides a regulated operating voltage 502 to the DC power lines 110, 112 in a first mode. Fig.15 At 1506, the mode control and power conversion circuit 106 (eg, Figure 7) in the second mode stops providing the regulated operating voltage 502 to the DC power lines 110, 112.

[0141] Reference Fig.10 , 15 16, another example of method 1000 continues from 1506 to 1602. In this example, the mode control and power conversion circuit 106 (e.g., Figure 7 ) includes a switching converter circuit 702 and a converter controller circuit 704. Fig.16 At 1602, the switching converter circuit 702 (eg, Figure 7 ) receives a DC string voltage 120. Fig.16 At 1604, the switching converter circuit 702 (eg, Figure 7 ) converts the DC string voltage 120 to a regulated operating voltage 502 in a first mode. Fig.16 At 1606, the switching converter circuit 702 (eg, Figure 7 ) in the second mode, converting the DC string voltage 120 to the standby voltage 124. Fig.16 At 1608, converter controller circuit 704 receives second signal 118 from receiver circuit 104. Fig.16 At 1610, in response to the second signal 118 being changed to the second state, the converter controller circuit 704 (eg, Figure 7 ) controls the switching converter circuit 702 by switching the switching converter circuit 702 from the first mode to the second mode. In response to the second signal 118 being set to the first state, the converter controller circuit 704 switches the switching converter circuit 702 to the first mode.

[0142] Reference Fig.17 , for rapid shutdown of PV module 102 (e.g., Figure 1 ) includes an example of a PVRSS 1700 including a starter device 1702, a transmitter circuit 116, and a controller circuit 100. For example, Fig.17 The controller circuit 100 is referred to as a fast shutdown controller circuit. The starter 1702 switches between a first state and a second state. The first state sets the fourth signal 1704 to a first state to enable the system to operate in a first mode. For example, Fig.17The fourth signal 1704 is referred to as a fast shutdown signal. The second condition of the initiator 1702 changes the fourth signal 1704 to a second state to trigger operation of the system in the second mode. The first state of the fourth signal 1704 is, for example, an activated state, an on state, a logic 1 state, or any suitable state indicating that normal operation of the PVRSS 1700 is enabled. The second state of the fourth signal 1704 is, for example, a deactivated state, an off state, a logic 0 state, or any suitable state indicating that normal operation of the PVRSS 1700 is disabled.

[0143] The transmitter circuit 116 receives the fourth signal 1704 from the initiator 1702. The transmitter circuit 116 generates the first signal 108 in response to the fourth signal 1704. For example, Fig.17 The first signal 108 is referred to as a KA signal. The KA signal may be transmitted one or more times within a frame. The frame may be transmitted periodically or asynchronously within a first predetermined time period. In another example, the first signal 108 may be a shutdown signal. The shutdown signal may be transmitted asynchronously in response to a shutdown event. The shutdown signal may be transmitted multiple times to ensure detection.

[0144] The controller circuit 100 includes a receiver circuit 104 (eg, Figure 1 ) and mode control and power conversion circuit 106. Figure 1-9 Various examples of controller circuit 100 are described. In various examples, controller circuit 100 of PVRSS 1700 implements Figure 10-16 Various examples of methods for rapidly shutting down PV modules are described in .

[0145] In one example of the PVRSS 1700, the RLC filter 126 or any suitable filter provides a filtered version of the DC power lines 110, 112 with the first signal 108 to the controller circuit 100. In another example of the PVRSS 1700, the first signal 108 is a wireless communication signal (e.g., WiFi, Zigbee, or any suitable wireless signal), and the controller circuit 100 includes a wireless receiver for receiving the first signal 108 from the transmitter circuit 116. In another example of the PVRSS 1700, the first signal 108 is a wired control line communication signal (e.g., a wire, cable, bus, or any conductor suitable for a wired control signal), and the controller circuit 100 includes an input node for receiving the first signal 108 from the transmitter circuit 116. In one example, a Schottky diode 128 or any suitable bypass diode is connected from the output node 125 of the controller circuit 100 to the RLC filter 126 or the DC power line return portion 112. Under conditions where the controller circuit 100 does not output a voltage, the Schottky diode 128 allows a DC current to pass.

[0146] In another example of the PVRSS 1700, the first signal 108 (e.g., KA signal) is repeatedly transmitted by the transmitter circuit 116 to allow normal operation. In one example, after filtering and demodulating the communication signal from the DC power lines 110, 112, the controller circuit 100 repeatedly detects the presence of the first signal 108. For example, if at least one first signal 108 is detected within a second predetermined time period, the controller circuit 100 considers the first signal 108 to be present and operates in a normal mode. Conversely, if the first signal 108 is not detected within the second predetermined time period, the controller circuit 100 considers the first signal 108 to be absent and operates in an off mode. The second predetermined time period is, for example, less than or equal to the first predetermined time period associated with repeated transmissions of the first signal 108.

[0147] In another example of the PVRSS 1700, the first signal 108 (e.g., a shutdown signal) is transmitted at least once by the transmitter circuit 116 to disable normal operation. The controller circuit 100 operates in the normal mode based on the absence of the first signal 108. The controller circuit 100 operates in the shutdown mode based on the presence of the first signal 108. In this example, the controller circuit 100 processes the shutdown signal differently from the KA signal, but controls the operation in the same manner even though the logic for processing the shutdown signal and the KA signal is different. In other words, the controller circuit 100 operates in the normal mode based on the presence of the KA signal and / or the absence of the shutdown signal, and operates in the shutdown mode based on the absence of the KA signal and / or the presence of the shutdown signal.

[0148] In another example of PVRSS 1700, if at least one first signal 108 is detected, the receiver circuit 104 considers the first signal 108 to be present. To ensure detection, the transmitter circuit 116 may retransmit the first signal 108 multiple times during the first predetermined time. Conversely, if the first signal 108 is not detected during the second predetermined time, the receiver circuit 104 considers the first signal 108 to be absent.

[0149] In another example of the PVRSS 1700, the first signal 108 is a PLC signal. In this example, the controller circuit 100 receives the PLC signal via the DC power lines 110, 112 between the PV module 102 and the DC to AC inverter 114. In another example of the PVRSS 1700, the transmitter circuit 116 transmits the first signal 108 on the DC power lines 110, 112 in a spread frequency shift keying (S-FSK) waveform that complies with the PLC protocol requirements of the SunSpec Interoperability Specification (Communication Signal for Rapid Shutdown, Version 34). In another example of the controller circuit 100, the first signal 108 is a wireless communication signal. In another example of the controller circuit 100, the first signal 108 is a wired control line communication signal.

[0150] Modifications are possible in the described examples, and other examples are possible, within the scope of the claims.The various circuits described above may be implemented using any suitable combination of discrete components, ICs, processors, memory, storage, and firmware.

Claims

1. A controller circuit for a photovoltaic module, i.e., a PV module, the controller circuit comprising: a receiver circuit configured to receive a first signal from a transmitter circuit and to change a second signal from a first state to a second state in response to the first signal; as well as a mode control and power conversion circuit configured to: receive a direct current voltage (DC voltage) from a PV cell string; receive the second signal from the receiver circuit; and switching from a first mode to a second mode in response to the second signal being in the second state, wherein in the second mode the mode control and power conversion circuit is configured to convert the DC voltage into a backup voltage and provide the backup voltage to the DC power line, and in the first mode the backup voltage is less than an operating voltage provided by the mode control and power conversion circuit.

2. The controller circuit of claim 1, wherein the PV module comprises the controller circuit.

3. The controller circuit of claim 1, wherein the controller circuit is an integrated circuit (IC).

4. The controller circuit of claim 1, wherein the standby voltage is 2.5 volts DC or less.

5. The controller circuit of claim 1 , wherein the first signal is repeatedly transmitted to enable normal operation of the PV module, and wherein the receiver circuit is configured to set the second signal to the first state in response to the presence of the first signal and to change the second signal to the second state in response to the absence of the first signal.

6. The controller circuit of claim 1 , wherein the first signal is transmitted at least once to disable normal operation, and wherein the receiver circuit is configured to set the second signal to the first state in response to an absence of the first signal and to change the second signal to the second state in response to a presence of the first signal. 7 . The controller circuit of claim 1 , wherein the first signal is one of a power line communication signal (PLC signal), a wireless communication signal, and a wired control line communication signal. 8 . The controller circuit of claim 1 , wherein the second signal is a digital signal having digital logic levels indicating activation of the first mode in the first state and deactivation of the first mode in the second state.

9. The controller circuit of claim 1, wherein the controller circuit is configured to receive the DC voltage from a first PV submodule of the PV module, the first PV submodule comprising the PV cell string, wherein the mode control and power conversion circuit is configured to receive the DC voltage from the first PV submodule; wherein the receiver circuit is configured to provide the second signal to a second controller circuit; wherein the second controller circuit is configured to receive a second DC voltage from a second PV cell string of a second PV submodule of the PV module, and to switch from the first mode to the second mode in response to the second signal being in the second state, and wherein in the second mode the second controller circuit is configured to convert the second DC voltage into a second backup voltage, and to provide the second backup voltage to the DC power line so that the second backup voltage is connected in series with the backup voltage.

10. The controller circuit of claim 9, wherein the second controller circuit is configured to change a third signal from a first state to a second state in response to the second signal being in the second state, and provide the third signal to a third controller circuit; wherein the third controller circuit is configured to receive a third DC voltage from a third PV cell string of a third PV submodule of the PV module, and to switch from the first mode to the second mode in response to the third signal being in the second state, wherein in the second mode the third controller circuit is configured to convert the third DC voltage to a third backup voltage, and to provide the third backup voltage to the DC power line so that the third backup voltage is connected in series with the backup voltage and the second backup voltage.

11. The controller circuit of claim 1, wherein In the second mode the mode control and power conversion circuit is configured to decouple the operating voltage from the DC power line.

12. The controller circuit of claim 1, wherein the mode control and power conversion circuit comprises: a regulator circuit configured to receive the DC voltage and convert the DC voltage to the backup voltage; as well as A switch device having an input terminal, a control terminal and an output terminal, the switch device being configured to receive the backup voltage from the regulator circuit at the input terminal, to receive the second signal from the receiver circuit at the control terminal, and to provide the backup voltage to the DC power line via the output terminal in response to the second signal being in the second state, wherein the switch device is configured to decouple the backup voltage from the output terminal in response to the second signal being in the first state.

13. The controller circuit of claim 1 , wherein in the first mode the mode control and power conversion circuit is configured to convert the DC voltage to the operating voltage and provide the operating voltage to the DC power line in the first mode; Wherein the mode control and power conversion circuit is configured to stop providing the operating voltage to the DC power line in the second mode.

14. A controller circuit for a photovoltaic module (PV module), the controller circuit comprising: a receiver circuit configured to receive a first signal from a transmitter circuit and to change a second signal from a first state to a second state in response to the first signal; as well as A mode control and power conversion circuit, the mode control and power conversion circuit comprising: a switching converter circuit configured to receive a direct current voltage (DC voltage) from a PV cell string and to convert the DC voltage to an operating voltage in a first mode and to convert the DC voltage to a standby voltage in a second mode; as well as a converter controller circuit configured to receive the second signal from the receiver circuit, switch the switching converter circuit to the first mode in response to the second signal being in the first state, and switch the switching converter circuit from the first mode to the second mode in response to the second signal being in the second mode.

15. A method for rapidly shutting down a photovoltaic module, i.e., a PV module, comprising: providing an operating voltage in a first mode by mode control of the controller circuit and the power conversion circuit; receiving a first signal at a receiver circuit of the controller circuit for the PV module, the first signal being received from a transmitter circuit; changing a second signal from a first state to a second state at the receiver circuit, the changing being based on the first signal; receiving a direct current voltage (DC voltage) at the mode control and power conversion circuit, the DC voltage being received from a PV cell string; receiving the second signal from the receiver circuit at the mode control and power conversion circuit; switching the mode control and power conversion circuit from the first mode to a second mode in response to the second signal being in the second state; converting the DC voltage to a standby voltage at the mode control and power conversion circuit in the second mode, the standby voltage being less than the operating voltage; as well as The backup voltage is provided from the mode control and power conversion circuit to a DC power line between the PV module and a DC to AC inverter in the second mode.

16. The method of claim 15, further comprising the controller circuit receiving the DC voltage from a first PV submodule of the PV module, the first PV submodule comprising the PV cell string, and the mode control and power conversion circuit receiving the DC voltage from the first PV submodule, and the method further comprising: providing the second signal from the receiver circuit to a second controller circuit; receiving, at the second controller circuit, a second DC voltage from a second string of PV cells of a second PV submodule of the PV module; switching the second controller circuit from the first mode to the second mode in response to the second signal being in the second state; converting the second DC voltage to a second standby voltage at the second controller circuit in the second mode; as well as The second backup voltage is provided from the second controller circuit to the DC power line in the second mode such that the second backup voltage is connected in series with the backup voltage.

17. The method according to claim 16, further comprising: changing a third signal from a first state to a second state at the second controller circuit in response to the receiver circuit placing the second signal in the second state; providing the third signal from the second controller circuit to a third controller circuit; receiving, at the third controller circuit, a third DC voltage from a third PV cell string of a third PV submodule of the PV module; switching the third controller circuit from the first mode to the second mode in response to the third signal being in the second state; converting the third DC voltage to a third standby voltage at the third controller circuit in the second mode; as well as The third backup voltage is provided from the third controller circuit to the DC power line in the second mode such that the third backup voltage is connected in series with the backup voltage and the second backup voltage.

18. The method according to claim 15, further comprising: providing the operating voltage from the mode control and power conversion circuit to the DC power line in the first mode; as well as The operating voltage is decoupled from the DC power line at the mode control and power conversion circuit in the second mode.

19. The method of claim 15, wherein the mode control and power conversion circuit comprises a regulator circuit and a switching device, the method further comprising: receiving the DC voltage at the regulator circuit; converting the DC voltage to the standby voltage at the regulator circuit; receiving the backup voltage from the regulator circuit at an input terminal of the switching device; receiving the second signal from the receiver circuit at a control terminal of the switching device; providing the backup voltage to the DC power line via an output terminal of the switching device in response to the second signal being in the second state; as well as The backup voltage is decoupled from the output terminal of the switching device in response to the second signal being in the first state.

20. The method of claim 15, further comprising: providing a regulated operating voltage from the mode control and power conversion circuit to the DC power line in the first mode; as well as Supply of the regulated operating voltage from the mode control and power conversion circuit to the DC power line is stopped in the second mode.

21. A method for rapidly shutting down a photovoltaic module (PV module), the PV module comprising: A controller circuit, the controller circuit comprising: a receiver circuit and a mode control and power conversion circuit, the mode control and power conversion circuit comprising: a switching converter circuit and a converter controller circuit, the method comprising: receiving, at the receiver circuit, a first signal from a transmitter circuit; changing a second signal from a first state to a second state at the receiver circuit, the changing being based on the first signal; receiving a direct current voltage (DC voltage) at the switching converter circuit; converting the DC voltage to an operating voltage at the switching converter circuit in a first mode; converting the DC voltage to a backup voltage at the switching converter circuit in a second mode; receiving, at the converter controller circuit, the second signal from the receiver circuit; and In response to the second signal being in the second state, switching the switching converter circuit from the first mode to the second mode; and The switching converter circuit is switched to the first mode in response to the second signal being in the first state.

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