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EP-4492613-B1 - DC BUS MANAGEMENT

EP4492613B1EP 4492613 B1EP4492613 B1EP 4492613B1EP-4492613-B1

Inventors

  • HARGASH, Asaf
  • GOMBERG, BRYON ROOS

Dates

Publication Date
20260513
Application Date
20240712

Claims (15)

  1. An apparatus comprising: a power converter (206), the power converter comprising direct current, DC, output terminals; and a controller (210), wherein the controller is configured to: receive (302) a first measured voltage at the DC output terminals, determine (304) that the first measured voltage is equal to zero, set (308) the power converter to output a first output voltage (V1), based on the first measured voltage being determined to equal zero, after setting the power converter to output the first output voltage, receiving a second measured voltage at the DC output terminals, determine that the second measured voltage is equal to the first output voltage, send (310) query communications to additional devices (204,216) connected to the DC output terminals, based on the second measured voltage being determined to equal the first output voltage (V1), and after the additional devices have responded (312) to the query communications, set the power converter to output a second output voltage (V2).
  2. The apparatus of claim 1, wherein the query communications are power line communications on the DC output terminals or wireless communications.
  3. The apparatus of claim 1 or claim 2, wherein the controller (210) is configured to determine that the second measured voltage is equal to the first output voltage for a predetermined time, and based on the second measured voltage being determined to equal the first output voltage for the predetermined time, set the power converter to output the second output voltage (V2).
  4. The apparatus of any one of the preceding claims, wherein the controller (210) is configured to: after setting the power converter (206) to output the second output voltage, receive a third measured voltage at the DC output terminals, determine that the third measured voltage is equal to the second output voltage, send (318) power line query communications on the DC output terminals to second additional devices connected to the DC output terminals, based on the third measured voltage being determined to equal the second output voltage (V2), after the second additional devices have responded (320) to the power line query communications, set the power converter to output a third output voltage (V3).
  5. The apparatus of claim 4, wherein the controller (210) is configured to determine that the third measured voltage is equal to the second output voltage for a predetermined time, and based on the third measured voltage being determined to equal the second output voltage for the predetermined time, set the power converter to output the third output voltage (V3).
  6. The apparatus of claim 4 or claim 5, wherein the first output voltage (V1) is below 50 volts DC, the second output voltage (V2) is between 50 volts DC and 240 volts DC, and the third output voltage (V3) is between 240 volts DC and 1500 volts DC.
  7. The apparatus of claim 1, wherein the controller (210) is configured to: receive (502) a first measured current supplied to the DC output terminals; determine (504) that the first measured current is greater than a first current threshold; set (506) the power converter (206) to reduce an output voltage of the power converter by a first predetermined amount, based on the first measured current being determined as greater than the first current threshold; receive a second measured current supplied to the DC output terminals; determine (508) that the second measured current being greater than a second current threshold; set (510) the power converter to reduce the output voltage of the power converter by a second predetermined amount, based on the second measured current being determined as greater than the second current threshold; receive a third measured current supplied to the DC output terminals; determine (512) that the third measured current being greater than a third current threshold; set (514) the power converter to reduce the output voltage of the power converter by a third predetermined amount relative, based on the third measured current being determined as greater than the third current threshold.
  8. The apparatus of any one of claims 1 to 7, wherein the power converter (206) is configured to limit output current to a current limit value.
  9. The apparatus according to claims 7 and 8, wherein the first current threshold is between 80% and 90% of the current limit value, the second current threshold is between 90% and 95% of the current limit value, and wherein the third current threshold is greater than 95% of the current limit value, and wherein the first predetermined amount is between 1 and 2.5 volts, the second predetermined amount is between 2.5 and 15 volts, and the third predetermined amount is between 5 and 25 volts.
  10. The apparatus of claim 1, wherein the power converter (206) is configured to limit output current to a current limit value, and wherein the controller (210) is configured to: receive a first measured current supplied to the DC output terminals; determine that the first measured current is greater than 95% of the current limit value and an output voltage of the power converter is greater than the first output voltage (V1); and set the power converter to output the first output voltage, based on the first measured current being determined as greater than 95% of the current limit value and the output voltage of the power converter being determined as greater than the first output voltage.
  11. The apparatus of claim 1, wherein the power converter (206) is configured to limit output current to a current limit value, and wherein the controller (210) is configured to: receive a first measured current supplied to the DC output terminals; determine that the first measured current is greater than 95% of the current limit value and an output voltage of the power converter is greater than the second output voltage (V2); and set the power converter to output the second output voltage, based on the first measured current being determined as greater than 95% of the current limit value and the output voltage of the power converter being determined as greater than the second output voltage.
  12. The apparatus of any one of the preceding claims, wherein the apparatus comprises a DC bus and said additional devices, and wherein the DC output terminals are connected to the DC bus (202) and the additional devices (204,216) are connected to the DC bus.
  13. The apparatus of any one of the preceding claims, further comprising a memory (218) configured to store data related to the additional devices, and wherein the controller is configured to, based on the data related to the additional devices, set the power converter to output the second output voltage.
  14. The apparatus of claim 13, wherein the data related to the additional devices (204,216) is based on at least one of: a state of charge of at least one of the additional devices, power usage of at least one of the additional devices, time usage related to at least one of the additional devices, or weather usage related to at least one of the additional devices.
  15. A method comprising: receiving (302) a first measured voltage of a direct current, DC, output terminal of a power converter (206), determining (304) that the first measured voltage is equal to zero, setting (308), based on the first measured voltage being determined to equal zero, the power converter to output a first output voltage (V1), receiving a second measured voltage of the DC output terminal of the power converter (206), determining (306) that the second measured voltage is equal to the first output voltage, sending (310), based on the second measured voltage being determined to equal the first output voltage, power line communications on the DC output terminals to query additional devices (204,216) connected to the DC output terminals, determining (312) that the additional devices have responded to the power line communications, and setting (316), based on determining the additional devices have responded to the power line communications, the power converter to output a second output voltage (V2).

Description

BACKGROUND The present invention relates to an apparatus comprising a power converter, as well as to a corresponding method. In an electric power system, a direct current (DC) bus may be used to connect and distribute power between different devices of the power system. The DC bus may include busbars. The busbars together with electrical wires may be used to connect the different devices of the power system to each other. The busbars and electrical wires may be made from electrically conductive material, such as metal. The busbars and electrical wires may be covered with insulating material. The different devices of the power system may include power sources that provide power to the DC bus, or loads that take power from the DC bus. US2015295413 discloses a remote-controlled photovoltaic string combiner is described that selects strings to be combined to a first photovoltaic output circuit or to a second photovoltaic output for the purpose of either controlling the charging of a battery connected to the first photovoltaic output circuit or for diverting current to a diversion load such as a grid-tie inverter. Strings are selected by energizing relays from one or other inverter such that when neither inverter is operating, all strings are deselected and both photovoltaic output circuits are deenergized. US2021092814 discloses an operating method for a light-emitting diode (LED) power supply includes the following operations: controlling an output voltage to be a first voltage by a control circuit; detecting a load current by a detection circuit; maintaining the output voltage as the first voltage by a constant voltage control circuit when the load current is greater than zero, changing the output voltage from the first voltage to a second voltage by the control circuit when the load current is equal to zero, and the second voltage being greater than the first voltage. US2023166633 discloses a power control system for a propulsion system of a vehicle includes an energy storage system including a pre-charge circuit and one or more battery packs. A DC-DC converter is connected to the energy storage system and including a first capacitor, a first plurality of power switches and an inductor. A power inverter module is connected to the DC-DC converter and including a second capacitor and a second plurality of power switches. A controller is configured to pre-charge the first capacitor of the DC-DC converter and the second capacitor of the power inverter module and control operating modes of the DC-DC converter and the power inverter module. CN115642679 discloses a charging device, a charging pile and a charging system. The charging device includes a positive bus bar, a negative bus bar, a DC/DC conversion circuit and a slow start circuit; The input end is connected, and the input end of the DC/DC conversion circuit is connected to the photovoltaic device or the energy storage device through the positive bus bar and the negative bus bar; and then the DC/DC conversion circuit can have a first voltage between the positive bus bar and the negative bus bar that is greater than or equal to When the first threshold is reached, power conversion is performed on the second voltage received from the photovoltaic device or the energy storage device, and the second voltage after power conversion is output. SUMMARY The present invention is defined by independent claims 1 and 15. Preferred embodiments of the invention are subject-matter of the dependent claims. Embodiments in the description and figures which do not fall within the scope of the claims are to be interpreted as examples or background information. Systems, apparatuses, and methods are described for DC bus management. The systems, apparatuses, and methods may be used for startup, management, and shutdown of a relatively high voltage DC power system connected to the DC bus. In some examples, a power device may provide power at different ramp up voltage levels to the DC bus to ramp up the voltage of the DC bus from a zero voltage level to an operating voltage level. For example, the power device may be configured to provide power at a first lowest voltage level, provide power at a second medium voltage level, and provide power at a third highest voltage level. The third voltage level may be the operating voltage level. There may be more than three voltage levels or less than three voltage levels. For example, if there are four voltage levels there may be a safety voltage level, a low voltage level, a medium voltage level, and a high voltage level. The high voltage level may be the operating voltage level. If there are three voltage levels they may be low, medium and high, or safety, low and high, or safety, medium and high, etc. The voltage levels may be voltage values, or ranges of values. In some examples, the power device may provide power at different ramp down voltage levels to the DC bus to ramp down the voltage of the DC bus from an operating voltage level to a