Control devices, power conditioners, and heat pump systems

Abstract

In a device that receives and supplies DC power to a DC bus to which two or more devices are connected, interference between the two or more devices is suppressed in the voltage control of the DC bus. [Solution] A control device connected to a DC link section equipped with a capacitor, for controlling equipment that transmits and receives power to and from the DC link section, the control device comprising: a first current value acquisition unit that acquires a detected value of a first current flowing from the capacitor to equipment other than the equipment connected to the DC link section; a voltage value acquisition unit that acquires a detected value of the capacitor's voltage; and an adjustment unit that adjusts a second current to which the equipment transmits and receives power to and from the DC link section using the detected voltage and the detected value of the first current.

Description

[Technical Field] 【0001】 This disclosure relates to a control device, a power conditioner, and a heat pump system. [Background technology] 【0002】 Patent Document 1 discloses a DC power supply device configured by connecting multiple devices in parallel to a DC power supply, each device being configured by connecting an inductive element and a capacitive element in series, and the capacitive element and a load in parallel, wherein each device includes an electrical quantity detection means for detecting one or more of the following: load current flowing through the load, current flowing through the inductive element, voltage applied to the inductive element, voltage applied to the capacitive element, and current flowing through the capacitive element, and a control means for controlling each load based on the output of the electrical quantity detection means so as to reduce the inductive current component due to interference between each device. [Prior art documents] [Patent Documents] 【0003】 [Patent Document 1] Japanese Patent Publication No. 2013-187945 [Overview of the Initiative] [Problems that the invention aims to solve] 【0004】 When controlling the voltage of a DC bus (DC link section) to which multiple devices are connected, high-precision control is required because the power state of each device connected to the DC bus changes sequentially. If each device controls the voltage of the DC bus individually, the system becomes redundant and may cause mutual interference. This disclosure aims to suppress interference between two or more devices in voltage control of a DC bus in a device that receives and supplies DC power to a DC bus to which two or more devices are connected. [Means for solving the problem] 【0005】 The control device in the first aspect is a control device connected to a DC link section equipped with a capacitor, and controls equipment that transmits and receives power to and from the DC link section, the control device comprising: a first current value acquisition unit that acquires a detected value of a first current flowing from the capacitor to equipment other than the equipment connected to the DC link section; a voltage value acquisition unit that acquires a detected value of the voltage of the capacitor; and an adjustment unit that adjusts a second current to which the equipment transmits and receives power to and from the DC link section using the detected voltage value and the detected value of the first current. In this case, in equipment that receives and supplies DC power to a DC bus to which two or more devices are connected, interference between the two or more devices in the voltage control of the DC bus can be suppressed. The control device in the second aspect is the control device in the first aspect, wherein the adjustment unit calculates a target value for the first current using the detected voltage value, and adjusts the second current that the device transmits and receives power to and from the DC link unit using the difference between the target value of the first current and the detected value of the first current. In this case, interference between devices can be suppressed without using information from other devices. The control device according to the third aspect is a control device according to the first or second aspect, wherein the device comprises a power conversion circuit, the control device comprises a second current value acquisition unit for acquiring a detected value of the second current, the adjustment unit outputs a control command for controlling the power conversion circuit, calculates the high-frequency component of the second current using the detected value of the second current, calculates the high-frequency component of the voltage using the detected value of the voltage, calculates the low-frequency component of the control command using the control command, calculates a first manipulated variable using the high-frequency component of the second current, calculates an interference amount using the high-frequency component of the voltage, and calculates a new control command using the first manipulated variable, the interference amount, and the low-frequency component of the control command. In this case, interference via the DC link can be canceled out with simple calculations. The power conditioner in the fourth aspect comprises a control device according to any of the first, third, or fourth aspects; a DC link section equipped with a capacitor; a converter connected to the DC link section and controlled by the control device; and a grid-connected inverter configured to be connectable to a grid power supply and connected to the DC link section. In this case, in a device that receives and supplies DC power to a DC bus to which two or more devices are connected, interference between the two or more devices in the voltage control of the DC bus can be suppressed. The heat pump system in the fifth aspect comprises a control device according to any of the first, third, or fourth aspects; a DC link section equipped with a capacitor; a converter connected to the DC link section; a refrigeration device connected to the DC link section; and a grid-connected inverter configured to be connectable to a grid power supply and connected to the DC link section, wherein the control device is configured to control the converter or the refrigeration device. In this case, in a device that receives and supplies DC power to a DC bus to which two or more devices are connected, interference between the two or more devices in the voltage control of the DC bus can be suppressed. [Brief explanation of the drawing] 【0006】 [Figure 1] This figure shows the circuit configuration of the power optimization system according to the first embodiment. [Figure 2] This is a control block diagram of the control device according to the first embodiment. [Figure 3] This is a simplified diagram of the control block diagram shown in Figure 2. [Figure 4] This figure shows the circuit configuration of the power optimization system according to the second embodiment. [Figure 5] This is a control block diagram of the control device according to the second embodiment. [Figure 6] This is a simplified diagram of the control block diagram in Figure 5. [Figure 7] This is a control block diagram of the control device for a modified example 1 of the second embodiment. [Figure 8] This is a simplified diagram of the control block diagram in Figure 7. [Figure 9]This figure shows the circuit configuration of a power optimization system according to a modified example 2 of the second embodiment. [Figure 10] This is a control block diagram of the control device according to the second embodiment. [Figure 11] This figure shows the circuit configuration of the power optimization system according to the third embodiment. [Figure 12] This figure shows the circuit configuration of the power optimization system according to the fourth embodiment. [Figure 13] This is a control block diagram of the control device according to the fourth embodiment. [Figure 14] This is a control block diagram of the control device for a modified example 1 of the fourth embodiment. [Figure 15] This is a control block diagram of the control device for a modified example 2 of the fourth embodiment. [Figure 16] This figure shows the circuit configuration of the power optimization system according to the fifth embodiment. [Figure 17] This is a control block diagram of the control device according to the fifth embodiment. [Figure 18] This is a flowchart of the current command distribution process in the fifth embodiment. [Figure 19] This figure shows a modified example 1 of the fifth embodiment. [Figure 20] This is a control block diagram of a modified example 1 of the fifth embodiment. [Figure 21] This figure shows a modified example 2 of the fifth embodiment. [Figure 22] This is a control block diagram of a modified example 2 of the fifth embodiment. [Figure 23] This is a diagram showing the system configuration of the sixth embodiment. [Modes for carrying out the invention] 【0007】 The embodiments will be described in detail below with reference to the attached drawings. <First Embodiment> [Overall structure] Figure 1 is a diagram showing the circuit diagram of the power optimization system 1 according to the first embodiment. In the first embodiment, a power optimization system 1 is described that suppresses interference in the voltage control of a DC link section between two or more devices when one of the devices is a converter, in a system that controls a DC link section to which two or more devices are connected. The power optimization system 1 comprises a DC link section 20, a converter 30, a power supply 40, other devices 50, and a control device 101. 【0008】 The converter 30 transmits and receives power to the DC link section 20. The power supply 40 supplies DC power to the converter 30. The power supply 40 is not particularly limited, but examples include solar cells and storage batteries. Other equipment 50 is connected to the DC link section 20 and transmits and receives power to the DC link section 20. Other equipment 50 is not particularly limited, but examples include electrical appliances such as refrigeration equipment, air conditioners, and water heaters. The control device 101 controls the DC link section 20 and the converter 30. 【0009】 The DC link section 20 includes a capacitor 35. The capacitor 35 smooths the output of the converter 30. The capacitance value of this capacitor 35 is denoted as C. The converter 30 comprises a switch unit 31, a reactor 32, and a resistor 33. In the converter 30, the switch unit 31, reactor 32, and resistor 33 are arranged in that order from the upstream side in the direction of current flow. The reactance value of the reactor 32 is L1, and the resistance value of the resistor 33 is r1. The switch unit 31 comprises two switch elements 31a and 32b. The DC current from the power supply 40 is stepped down by the synchronous operation of switch elements 31a and 31b. 【0010】 The control device 101 includes a device for processing various types of information. The control device 101 can be configured using a microcomputer and a memory device containing software for operating it. The control device 101 further includes a first ammeter 71, a second ammeter 72, a first voltmeter 73, and a second voltmeter 74. The first ammeter 71 measures the current flowing from the capacitor 35 to the other device 50. The second ammeter 72 measures the current flowing between the converter 30 and the DC link section 20. The first voltmeter 73 measures the voltage of the capacitor 35. The second voltmeter 74 measures the voltage of the power supply 40. The first ammeter 71, the second ammeter 72, the first voltmeter 73, and the second voltmeter 74 transmit the measured values to the control device 101. The transmission of the measured values to the control device 100 may be performed by wire or wirelessly. Also, let the current value measured by the first ammeter 71 be i e and let the current value measured by the second ammeter 72 be i1. Also, let the voltage value measured by the first voltmeter 73 be v LINK and let the value measured by the second voltmeter 74 be the voltage value v1. Also, at this time, let the output current of the converter be i out . The control target 11 of the control device 101 includes the DC link section 20 and the converter 30. The control device 101 transmits the duty ratio d1 to the converter 30 as information for controlling the converter 30. 【0011】 〔Construction of control means〕 From the voltage of the power supply 40, the voltage of the converter 30, the voltage of the reactor 32, the voltage of the resistor 33, and the voltage of the capacitor 35 in the power optimization system 1 shown in FIG. 1, Equation (1-1) holds as a differential equation. 【0012】 【Equation】 【0013】 Linearize Equation (1-1) near the equilibrium point. Here, let the equilibrium points of i1, d1, and v LINK be I1, D1, and V LINK , and let the amounts of variation around the equilibrium point be Δi1, Δd1, and Δv LINK . Then, i1 = I1 + Δi 1、 d1 = D1 + Δd1, v LINK = V LINK + ΔvLINK Then, we get equation (1-2). 【0014】 【number】 【0015】 At the equilibrium point, equation (1-3) holds true. 【number】 【0016】 Applying equation (1-3) to equation (1-2), we obtain equation (1-4) as a differential equation near the equilibrium point. 【0017】 【number】 【0018】 Furthermore, equation (1-5) holds true as a differential equation relating to the current in capacitor 35. 【0019】 【number】 【0020】 Similarly, equations (1-5) are linearized near the equilibrium point. e The equilibrium point is I e Let Δi be the amount of variation around the equilibrium point. e Then, i e =I e +Δi e This results in equation (1-6). 【0021】 【number】 【0022】 At the equilibrium point, equation (1-7) holds true. 【0023】 【number】 【0024】 Applying equation (1-7) to equation (1-6), we obtain equation (1-8) as a differential equation near the equilibrium point. 【0025】 【number】 【0026】 As described in equation (1-8), Δv LINK Δi1 and Δi e Since it includes Δi e It is subjected to interference by Δv. Therefore, the interference component is Δv L1 Decoherence is performed by defining it as shown in equation (1-9). 【0027】 【number】 【0028】 Applying equation (1-9) to equation (1-4) results in equation (1-4) becoming equation (1-10). 【0029】 【number】 【0030】 Transforming equation (1-10) yields equation (1-11). 【0031】 【number】 【0032】 According to equation (1-11), Δv L1 The transfer function from Δi1 is shown. 【0033】 [Control system configuration] Figure 2 is a control block diagram of the control device 101 according to the first embodiment. Based on equations (1-5) and (1-11) above, v LINK We will construct a control system that controls and i1. Here, v LINK By using feedback control, Δi1 * Compensator G that outputs v (s)112 and Δi1 are feedback controlled to Δv L1 * The control system uses a compensator G1(s)122 that outputs a signal. The control device 101 calculates the duty cycle d1 for controlling the converter 30 included in the controlled object 11. 【0034】 The control block of the control device 101 includes a voltage control unit 110, a current control unit 120, a non-interference control unit 130, a control command output unit 140, a first current high frequency unit 141, a second current high frequency unit 142, a voltage high frequency unit 143, and a command low frequency unit 144. 【0035】 [First current high frequency section] The first current high-frequency section 141 controls the first current i e This is fed back, and the first current i e The high-frequency component Δi e The first current high-frequency unit 141 outputs the first current i by, for example, the following method. e Calculate the high-frequency components. 【0036】 As the first method, the first current high-frequency unit 141 detects the first current i e The input is used, and the detected value i of the first current is passed through a filter that removes low-frequency components. e Detect the high frequency and convert this high frequency to Δi e Here, examples of filters that remove low-frequency components include high-pass filters and band-pass filters. The second method is to use the detected value i of the first current. e The input is used, and the low-frequency component of the second current is detected by passing it through a filter that removes the high-frequency component Δi1. Then, the detected value i of the first current is taken. e Subtracting the low-frequency component of the first current from this gives the high-frequency component Δi of the first current. eIn other words, the detected value i of the first current. e The difference between this and the low-frequency component of the first current is the high-frequency component Δi of the first current. e Here, examples of filters that remove high-frequency components include low-pass filters and moving average filters. As a third method, the detected i e and command value i e * The deviation i e -i e * Δi e This can be illustrated as an example. 【0037】 [Second current high frequency section] The second current high-frequency unit 142 feeds back the detected second current i1 and outputs the high-frequency component Δi1 of the second current i1. The second current high-frequency unit 142 calculates the high-frequency component Δi1 of the second current i1 by, for example, the method illustrated below. 【0038】 As the first method, the second current high-frequency section 142 takes the detected value i1 of the second current as input, detects the high frequency of the detected value i1 of the second current through a filter that removes low-frequency components, and sets this high frequency as Δi1. Here, examples of filters that remove low-frequency components include high-pass filters and band-pass filters. As a second method, the second current high-frequency section 142 takes the detected value i1 of the second current as input and detects the low-frequency component of the second current through a filter that removes the high-frequency component Δi1. Then, the high-frequency component Δi1 of the second current is obtained by subtracting the low-frequency component of the second current from the detected value i1 of the second current. In other words, the high-frequency component Δi1 of the second current is the difference between the detected value i1 of the second current and the low-frequency component of the second current. Here, examples of filters that remove high-frequency components include low-pass filters and moving average filters. The third method involves the detected i1 and the command value i1. * Deviation i1-i1 * One example is to define Δi1 as such. 【0039】 [Voltage High Frequency Section] The high-frequency voltage section 143 controls the voltage v of the capacitor 35. LINK The voltage v is fed back. LINK The high-frequency component Δv LINK The voltage high-frequency section 143 outputs the high-frequency component Δv, for example, by the method illustrated below. LINK Calculate. 【0040】 As the first method, the high-frequency voltage section 143 detects the voltage of the capacitor 35 v LINK The input is passed through a filter that removes low-frequency components, v LINK The high-frequency component Δv LINK This detects the low-frequency components. Examples of filters used to remove low-frequency components include high-pass filters and band-pass filters. As a second method, the voltage high-frequency section 143 detects the capacitor voltage v LINK The input is used, and the low-frequency component detected is passed through a filter that removes the high-frequency component. Then, the detected value of the voltage across capacitor 35 v is used. LINK Subtracting the low-frequency component of the voltage across capacitor 35 from this value gives v LINK The high-frequency component Δv LINK In other words, the detected value of the voltage across capacitor 35 is v. LINK The difference between the low-frequency component of the voltage across capacitor 35 and the high-frequency component Δv of the capacitor voltage is the difference between the low-frequency component and the voltage across capacitor 35. LINK Here, examples of filters that remove high-frequency components include low-pass filters and moving average filters. As a third method, the detected v LINK and command value v LINK * The deviation v LINK -v LINK * Δv LINK This can be illustrated as an example. 【0041】 [Control command low-frequency section] The command low-frequency unit 144 controls the control command value d1 * The input is the control command value d1 * Low-frequency component D1 *Outputs it. The command low-frequency section 144 calculates the low-frequency component D1 by, for example, the method exemplified below. * Calculates it. As the first method, with the command value d1 * as an input, the low-frequency component D1 * of the command value d1 * is detected through a filter that removes the high-frequency component. Here, examples of the filter that removes the high-frequency component include a low-pass filter and a moving average filter. As the second method, with the command value d1 * as an input, the delayed input by one control cycle is used as the low-frequency component D1 * . For example, it can be exemplified by a delay device that delays the command value d1 by one control cycle. 【0042】 〔Voltage control unit〕 The voltage control unit 110 acquires the command value v LINK of v LINK * , the measured value of v LINK , and Δi e output from the first current high-frequency section 141, and outputs the variation Δi1 * of the command value of the converter current. The voltage control unit 110 includes a subtractor 111, a compensator Gv(s) 112, and an adder 113. The subtractor 111 subtracts the measured value v LINK * from the command value v LINK . The compensator Gv(s) 112 calculates the variation amount Δi1 LINK * of the command value of the second current for compensating the difference between the command value v LINK and the measured value v. * Calculates it. The adder 113 adds the high-frequency component Δi e output from the first current high-frequency section 141 to the output from the compensator Gv(s) 112, and outputs it as the variation amount Δi1 * of the command value of the second current. 【0043】 〔Current control unit〕 The current control unit 120 uses the variation amount Δi1 of the command value of the second current i1 output by the voltage control unit 110 * and the high-frequency component Δi1 output by the second current high-frequency unit 142 as inputs, and outputs the variation amount Δv L1 of the command value of v L1 * for non-interference control. The current control unit 120 includes a subtractor 121 and a compensator G1(s) 122. The subtractor 121 subtracts the high-frequency component Δi1 output by the second current high-frequency unit 142 from the variation amount Δi1 * output by the voltage control unit 110. Then, the compensator G1(s) 122 calculates the variation amount Δv * of the command value of v for non-interference control based on (Δi1 L1 -Δi1). L1 * It outputs. 【0044】 〔Non-interference control unit〕 The non-interference control unit 130 performs non-interference control to compensate for the variation amount of the interference component. The non-interference control unit 130 includes an adder 131 and a divider 132. Here, the variation Δd1 * of the command value of the duty ratio d1 to the converter is obtained by the following formula. 【0045】 【Equation】 【0046】 The adder 131 adds Δv L1 * which is the output of the current control unit 120 and Δv LINK which is the output of the voltage high-frequency unit 143. Then, the divider 132 divides the output from the adder 131 by the voltage v1 of the power supply 40 as the denominator to obtain the variation amount Δd1 * of the command value of the duty ratio and outputs it. 【0047】 〔Control command output unit〕 The control command output unit 140 uses the variation Δd1 *And, control command value d1 * Low-frequency component D1 * Therefore, control command value d1 * Outputs the control command value d1. * It can be calculated using the following formula. 【0048】 【number】 【0049】 The control command output unit 140 is composed of an adder and the variation Δd1 of the control command * And, control command value d1 * Low-frequency component D1 * Adding these together, we get the control command value d1 * Outputs. 【0050】 Furthermore, the controlled device 11 includes an adder 161, four subtractors 171 to 174, and a multiplier 181. The subtractor 171 receives the control command value d1 from the control device 101. * The equilibrium point D1 is subtracted from and output as Δd1. Then, the multiplier 181 multiplies Δd1 and v1. Also, the subtractor 172 multiplies v LINK From equilibrium point V LINK Subtract the result (v) from the result of subtracting LINK -V LINK Subtracting ) gives Δv L1 Output as follows. 【0051】 Here, from equation (1-11) above, Δv L1 The transfer function G1 from to Δi1 is 1 / (L1S+r1). Then, adder 161 adds the equilibrium point I1 to Δi1 and outputs it as i1. Furthermore, subtractor 174 subtracts the measured value of the first current i from i1. e This is subtracted. Also, from equation (1-5) above, i1-i e from v LINK The transfer function G2 up to this point is (1 / Cs). 【0052】 Figure 3 is a modified version of the control block diagram in Figure 2. Next, the control block diagram in Figure 3 will be explained with reference to Figure 2. Figure 3 shows the equilibrium point D1 in Figure 2 and the control command value d1 output by the command low-frequency unit 144. * Low-frequency component D1 * We consider and to be identical, Δv LINK and (v LINK -V LINK This is a modified control block diagram, treating the two as identical. Equilibrium point D1 and control command value d1 output by command low frequency unit 144 * Low-frequency component D1 * If they are the same, the control command output unit 140 will output the control command value d1 * Low-frequency component D1 * The process of adding and the process of subtracting equilibrium point D1 by the subtractor 171 cancel each other out. In this case, the process of dividing by v1 as the denominator in the divider 132 and the process of multiplying by v1 in the multiplier 181 cancel each other out. Furthermore, Δv added by the adder 131 LINK Then, subtraction is performed by subtractor 173 (v LINK -V LINK If we consider them to be the same, they cancel each other out. If we remove these canceling parts from Figure 2, the current control unit 120 outputs Δv L1 * From the input Δv of the transfer function L1 The process up to this point can be omitted to show the result. In Figure 2, the processing of adder 161 and subtractor 174 is shown in Figure 3 as i e =I e +Δi e The processing is performed using subtractors 175 and 176. As shown in Figure 3, in the decoupling control block diagram, v LINK And, Δi e This has been fed back into the system. 【0053】 [Features of the first embodiment] A key feature of this control is that it compensates for the amount of interference variation in the output of the compensation means (current control compensator G1(s)112) that outputs the amount of variation, using non-interference control (ΔvLINK (Addition process) and the variation amount Δd1 of the command value * After determining the equilibrium point, add the command value d1 * The point is to calculate the following. By configuring it in this way, for example, the following effects can be obtained. First, interference via the DC link section 20 can be canceled with a simple calculation. Second, the output Δv of the compensator G1(s)112 L1 * Therefore, the output Δd1 of the non-interference control unit 130 * The calculations up to this point only calculate the amount of fluctuation, so even if the amount of fluctuation is small compared to the equilibrium point, control can be performed without being affected by overflow, underflow, rounding errors, etc. Thirdly, interference in the DC link section 20 is suppressed and unnecessary inputs and outputs are reduced, so the ripple to the capacitor 35 can be reduced and the capacitance of the capacitor 35 can be reduced. 【0054】 Fourthly, the error due to detector variability compensated by the compensator G1(s) is reduced, making it less susceptible to overflow, underflow, rounding errors, etc., resulting from error compensation. Detectors have variations due to manufacturing tolerances, operating temperature, etc. These variations can be modeled as variations related to gain and variations related to offset, for example v LINK The detector can be modeled by equation (1-14). 【0055】 【number】 【0056】 TIFF0007875535000015.tif38168 【number】 【0057】 TIFF0007875535000017.tif7160 【0058】 【number】 【0059】 TIFF0007875535000019.tif44168 【0060】 [Second Embodiment] Figure 4 shows the circuit configuration of the second embodiment. The second embodiment differs from the first embodiment in that it is a boost converter. Note that the same reference numerals are used for functions similar to those in the first embodiment, and their explanation is omitted here. The power optimization system 2 comprises a DC link section 20, a converter 330, a power supply 40, other equipment 50, and a control device 102. 【0061】 The converter 330 comprises a switch unit 31, a reactor 32, and a resistor 33. Compared to the converter 30 of the first embodiment, the configuration of the converter 330 is such that the reactor 32, resistor 33, and switch unit 31 are arranged in that order from upstream to downstream in the direction of current flow. In the second embodiment, the reactance value of the reactor 32 is L2, and the resistance value of the resistor 33 is r2. 【0062】 Furthermore, the control device 102 includes a first ammeter 71, a second ammeter 75, a first voltmeter 73, and a second voltmeter 74. The second ammeter 75 measures the current flowing between the resistor 33 and the switch unit 31. The current value measured by the second ammeter 75 is denoted as i2. The second ammeter 75 transmits the measured value to the control device 102. In the second embodiment, the value measured by the second voltmeter 74 is denoted as v2. 【0063】 [Construction of control means] In the power optimization system 2 shown in Figure 4, the voltage of the power supply 40, the voltage of the converter 30, the voltage of the reactor 32, the voltage of the resistor 33, and the voltage of the capacitor 35 give rise to the differential equation (2-1). 【0064】 【number】 【0065】 Similar to the first embodiment, linearizing equation (2-1) near the equilibrium point results in equation (2-2) as the differential equation near the equilibrium point. 【0066】 【number】 【0067】 Furthermore, equation (2-3) holds true as a differential equation relating to the current flowing through capacitor 35. 【0068】 【number】 【0069】 Similarly, when equation (2-3) is linearized near the equilibrium point, the differential equation near the equilibrium point becomes equation (2-4). 【0070】 【number】 【0071】 Here the interference component is Δv L2 Decoherence is performed by defining it as shown in equation (2-5). 【0072】 【number】 【0073】 Applying equation (2-5) to equation (2-2), equation (2-2) becomes equation (2-6). 【0074】 【number】 【0075】 Transforming equation (2-6) yields equation (2-7), and Δv L2The transfer function from Δi2 is shown. 【0076】 【Number】 【0077】 〔Configuration of the control system〕 FIG. 5 is a control block diagram of the control device 102 according to the second embodiment. Based on the above equations (2-3) and (2-5), v LINK is feedback-controlled to output the compensator G out * (s)212 for i, and the compensator G1(s)222 that feedback-controls i2 to output the variation Δv v (s)212 and i2 are used to form a control system. L2 * The control block of the control device 102 includes a voltage control unit 210, a current control unit 220, a non-interference control unit 230, a control command output unit 140, a voltage high-frequency unit 143, a command low-frequency unit 144, and a conversion unit 150. 【0078】 〔Voltage control unit〕 【0079】 The voltage control unit 210 includes a subtractor 111, a compensator Gv(s)212, and an adder 113. The subtractor 111 subtracts the measured value v from the command value v LINK * LINK The compensator Gv(s)212 calculates the command value i to compensate for the difference between the command value v LINK * LINK and the measured value v LINK out for the current i to compensate for the difference. out * * The adder 113 adds i to the output from the compensator Gv(s)212 and outputs it as the command value i e of the variation of the second current out * 【0080】 〔Conversion unit〕 The conversion unit 150 converts the command value i out * into i2 * Specifically, the divider 151 uses the command value i out * as the numerator and d2 * as the denominator to perform division. 【0081】 〔Current control unit〕 The current control unit 220 includes a subtractor 121 and a compensator G1(s) 222. The subtractor 121 subtracts the value i2 of the second current from the i2 * converted by the conversion unit 150. Then, the compensator G2(s) 222 calculates the variation Δv * of the command value of v for non-interference control based on (i2 L2 - i2). L2 * and outputs it. 【0082】 〔Non-interference control unit〕 The non-interference control unit 230 includes an adder 131, a multiplier 232, and a divider 132. Here, the variation Δd2 * of the command value of the duty ratio d2 to the converter 330 is obtained by the following equation (2-8). 【0083】 【Equation】 【0084】 According to equation (2-8), the multiplier 232 multiplies the low-frequency component D2 * output by the command low-frequency section 144 and the Δv LINK output by the voltage high-frequency section 143. Then, the adder 131 adds the command value Δv L2 * of the variation output by the current control unit 220 and the output from the multiplier 232. Furthermore, the divider 132 divides the output from the adder 231 as the numerator by V LINK output from the voltage high-frequency section 143 as the denominator to obtain Δd2 *Outputs. 【0085】 [Control command output unit] The control command output unit 140 outputs the control command variation Δd2 * And, control command value d2 * Low-frequency component D2 * Therefore, control command value d2 * Outputs the control command value d2. * The answer can be found using the following equation (2-9). 【0086】 【number】 【0087】 According to equation (2-9), the control command output unit 140 is composed of an adder, and the variation Δd1 of the control command * And, control command value d1 * Low-frequency component D1 * Add and output. 【0088】 Figure 6 is a simplified version of the control block diagram in Figure 5. Next, with reference to Figure 5, the control block diagram in Figure 6 will be explained. Figure 6 shows the equilibrium point D2 in Figure 5 and the control command value d2 output by the command low-frequency unit 144. * Low-frequency component D2 * We consider them to be the same, Δv LINK and (v LINK -V LINK This is a modified control block diagram, assuming that the two are identical. Equilibrium point D2 and control command value d2 output by control command output unit 140 * Low-frequency component D2 * If they are the same, the control command output unit 140 outputs the control command value d2 * Low-frequency component D2 * The process of adding and the process of subtracting equilibrium point D2 by subtractor 171 cancel each other out. Furthermore, in this case, the divider 233 subtracts equilibrium point V LINK The process involves dividing with the denominator, and multiplying by multiplier 181 to find the equilibrium point V LINK The multiplication operation cancels out. Furthermore, D2 is added by adder 231. * ×Δv LINK Then, D2(v) is subtracted by subtractor 173. LINK -V LINK ) and cancel each other out. If we remove these canceling parts from Figure 5, the output Δv of the current control unit 220 is obtained. L2 * Input Δv from transfer function G3 L2 The process up to this point can be omitted to show the result. 【0089】 <Modification 1 of the second embodiment> Modification 1 of the second embodiment is such that in the second embodiment, the output from the voltage control unit 210 is i out * In contrast, the output from the voltage control unit 210 was changed to a fluctuation amount Δi out * This is a block diagram of the configuration described above. 【0090】 Figure 7 is a control block diagram of the control device 102-1 of a modified example 1 of the second embodiment. The control device 102-1 includes a voltage control unit 210, a current control unit 220, a non-interference control unit 230, a control command output unit 140, a conversion unit 250, a first current high frequency unit 141, a second current high frequency unit 142, a voltage high frequency unit 143, and a command low frequency unit 144. 【0091】 The conversion unit 250 calculates the command value Δi out * Δi2 * The conversion unit 250 comprises a multiplier 251, a subtractor 252, and a divider 253. The multiplier 251 is used for equilibrium point I2 and Δd2 * Multiply by . Then, subtractor 252 outputs Δi from voltage control unit 210. out * From I2Δd2 * Subtracts from it. Furthermore, the divider 253 takes the output from the subtractor 252 as the numerator and calculates D2 * The output is obtained by dividing by the denominator. The processing in the conversion unit 250 is based on equation (2-4). Also, the subtractor 121 of the current control unit 220 subtracts Δi2 * from it, and the result of subtracting Δi2 becomes the input to the compensator G2(s) 222 of the current control unit 220. 【0092】 FIG. 8 is an omitted view of the control block diagram of FIG. 7. Next, while referring to FIG. 7, the control block diagram of FIG. 8 will be described. FIG. 8 assumes that the equilibrium point D2 in FIG. 7 and the control command value d2 output by the command low-frequency section 144 * are the same as the low-frequency component D2 * of d2, and assumes that Δv LINK is the same as (v LINK -V LINK ), and is a modified control block diagram. When the equilibrium point D2 and the low-frequency component D2 * of the control command value d2 output by the control command output section 140 * are the same, the process of adding the low-frequency component D2 * of the control command value d2 by the control command output section 140 and the process of subtracting the equilibrium point D2 by the subtractor 171 cancel each other out. Further, in this case, the process of dividing by the equilibrium point V * as the denominator by the divider 233 and the process of multiplying by the equilibrium point V LINK by the multiplier 181 cancel each other out. LINK Furthermore, D2 * ×Δv added by the adder 231 LINK and D2×Δv subtracted by the subtractor 173 LINK cancel each other out. If these canceling parts are omitted from FIG. 7, the process from when the current control unit 120 outputs Δv L2 * to the input Δv L2 to the transfer function G3 can be shown omitted. 【0093】 〔Differences between the Second Embodiment and the Modified Example of the Second Embodiment〕 As described above, the conversion formula between i2 * and i out * is, in the second embodiment, i2 * = i out* / d2 * In contrast, in modified example 1, Δi2 * =( Δi out -I2Δd2 * The difference is that it becomes ) / D2. Also, as the input to G2(s), in the second embodiment, i2 * In contrast to -i2, in Modification 1, Δi2 * It differs in that it is -Δi2. As a result, in Modification 1 of the second embodiment, the dynamic range can be increased because it is controlled by the amount of change. Compared to the second embodiment, Modification 1 of the second embodiment can distinguish minute signals more finely and the control accuracy is improved. On the other hand, compared to the second embodiment, Modification 1 of the second embodiment is more susceptible to noise because it is controlled by the amount of change. 【0094】 <Modification 2 of the second embodiment> Figure 9 is a diagram showing the circuit diagram of power optimization system 2-2 according to modified example 2 of the second embodiment. In the power optimization system 2-2, the position of the current measured by the second ammeter 76 is different from that of the power optimization system 2 of the second embodiment. The second ammeter 76 of the power optimization system 2-2 measures the current flowing from the converter 330 to the DC link section 20. In the modified version of the second embodiment, the value of the current measured by the second ammeter 76 is i2 ′ Let's assume this. i2 ′ And, i2, which was measured by the second ammeter 75 (see Figure 4) in the second embodiment, is i2 ′ Since =d2i2 holds true, equations (2-1) to (2-9) in the second embodiment can be modified as follows. 【0095】 【number】 【0096】 【number】 【0097】 【number】 【0098】 【number】 【0099】 【number】 【0100】 【number】 【0101】 【number】 【0102】 【number】 【0103】 【number】 【0104】 Figure 10 is a control block diagram of the control device 102-2 of a modified example 2 of the second embodiment. The control device 102-2 comprises a voltage control unit 210, a current control unit 220, a non-interference control unit 230-2, a high-frequency voltage unit 143, and a low-frequency command unit 144. 【0105】 [Voltage Control Unit] The voltage control unit 210 includes a subtractor 111, a compensator Gv(s) 212, and an adder 113. The subtractor 111 processes the command value v LINK * From the measured value v LINK Subtract it. The compensator Gv(s)212 uses the command value vLINK * and measured value v LINK Current i to compensate for the difference out Command value i out * Calculate. The adder 113 receives the output from the compensator Gv(s)212, i e Add this to the command value i of the fluctuation in the second current. out * Output as follows. 【0106】 [Current Control Unit] The current control unit 220 includes a subtractor 121 and a compensator G1(s)222. As is clear from Figure 9, i out Since i'2 is the same, the current control unit 220 outputs i'2 from the voltage control unit 210. out * i2' * It is treated as such. The subtractor 121 receives i2' output from the voltage control unit 210. * Subtract the value of the second current i2' from it. Then, the compensator G1(s)122 is (i2 * -i2) Based on non-interfering control v L2 The amount of variation Δv in the command value L2 * Outputs. 【0107】 [Non-interference control unit] The non-interference control unit 230-2 includes three multipliers 232, 235, and 236, a doubling unit 237, an adder 238, a subtractor 239, and a divider 240. Here, the variation Δd2 of the command value for the duty cycle d2 to the converter 230 (see Figure 9) is * This is calculated using the following equation (2-17). According to equation (2-17), the multiplier 236 receives the output of D2 from the command low-frequency unit 144. * Squaring the result. The multiplier 235 takes the output of the voltage high-frequency section 143. LINK Then, the command low-frequency unit 144 outputs D2 * Multiply by (D2) the output of multiplier 236. * ) 2 Then, the voltage high-frequency section 143 outputs Δv LINKMultiply by . Subtractor 239 takes the Δv output by compensator G1(s)122. L2 * And multiplier 232 output (D2 * ) 2 Δv LINK Subtract both from the other. The multiplier 237 subtracts the V output by 235. LINK D2 * It doubles the output of the 2V output by the 2V multiplier 237. The subtractor 238 takes the output of the 2V output by the 2V multiplier 237. LINK D2 * Subtract v2 from this. Divider 240 subtracts (-Δv) from the output of subtractor 239. L2 * -(D2 * ) 2 Δv LINK With this as the numerator, subtractor 238 outputs (2V LINK D2 * Divide by -v2) as the denominator. 【0108】 [Control command output unit] The control command output unit 140 is composed of an adder and the variation Δd1 of the control command * And, control command value d1 * Low-frequency component D1 * Add and output. 【0109】 [Features of the control system of modified example 2 of the second embodiment] The difference between the second embodiment and the modified example 2 of the second embodiment is that the current to be controlled is different. In this second embodiment, current control is performed on i2. The output of the voltage control is i2. ′ Therefore, i2 ′ Conversion process from i2 to i2 (i2=i2 ′ / d2 * This requires a conversion process, which can lead to delays and variations, potentially degrading the characteristics of voltage control. Modification 2 of the second embodiment is i2 ′ i2 ′ Current control is performed on the voltage control output i2. ′Since it handles the same values, no conversion processing is required, and because it is not affected by delays or variations caused by conversion processing, there is no risk of degrading the characteristics of the voltage control. On the other hand, since i2 is controlled indirectly, the control characteristics of i2 may be degraded compared to the second embodiment. Depending on the system requirements, either the second embodiment or the second modified embodiment may be selected. 【0110】 [Third Embodiment] Figure 11 is a diagram showing the circuit diagram of the power optimization system 3 according to the third embodiment. In the third embodiment, three or more devices 50-1, 50-2, ..., 50-N are connected to the DC link section 20. Examples of devices 50-1 and 50-2 in Figure 11 include, for example, a solar power generation system, an energy storage system, a grid-connected inverter, refrigeration equipment, and an air conditioner. In this embodiment, voltage control is performed only on device 50-1, and not on device 50-2. A feature of this configuration is that the sum of the currents flowing from the capacitor 35 of the DC link section 20 to all devices other than device 50-1 is defined as current i e The key point is that it is detected as such. By configuring it in this way, the voltage control characteristics of device 50-1 can be maintained even if the number of connected devices increases or decreases. Furthermore, in all devices, including device 50-1, the current control and non-interference control related to the fluctuation amount described in the first embodiment and the second embodiment, including modified versions, can be employed. By employing these controls, the effect of suppressing interference from other devices with simple control is obtained. 【0111】 [Fourth Embodiment] Figure 12 is a diagram showing the circuit diagram of the power optimization system 4 according to the fourth embodiment. The power optimization system 4 according to the fourth embodiment comprises a DC link section 20, a control device 104, a circuit 14-1, a circuit 14-2, ...circuit 50-N, and equipment 50-(N+1)...equipment 50-(N+M). Here, N is an integer of 2 or more, and M is an integer of 2 or more. 【0112】 The control device 104 checks the voltage v of the capacitor 35 of the DC link section 20. LINK The control device 104 also controls circuits 14-1, 14-2, ..., and 50-N. The DC link section 20 and circuits 14-1, 14-2, ..., and 14-N are shown in Figure 12 as the control targets 14 of the control device 104. The control device 104 includes a first ammeter 71 and a first voltmeter 73. The first ammeter 71 measures the current i flowing from the capacitor 35 to the other device 50. e The voltage v of capacitor 35 is measured. The first voltmeter 73 measures the voltage v LINK The measurement is taken. The measured value may be transmitted to the control device 104 by wire or by wireless connection. 【0113】 Circuit 14-1 is the circuit for device 50-1 (not shown), and functions as device 50-1 when controlled by control device 104. Similarly, circuit 14-N is the circuit for device 50-N (not shown), and functions as device 50-N when controlled by control device 104. In this embodiment, voltage control is performed in one or more of the devices 50-1 to 50-N, while voltage control is not performed in devices 50-(N+1) to (N+M). Current i flowing from capacitor 35 e However, the configuration is such that the current is equal to the sum of the currents flowing through all devices N+1 to (N+M) that do not undergo voltage control. 【0114】 Figure 13 is a schematic diagram of the control block of the control device 104 according to the fourth embodiment. Command value i out * The current command i of each device k ` * The difference from the first to third embodiments is that a distributor 80 is provided to divide the signal into multiple outputs. 【0115】 The controller 104 comprises a voltage control unit 210, a distributor 80, controller 104-1, controller 104-2, and controller 104-N. The voltage control unit 210 controls the current i measured by the first ammeter 71 (see Figure 12). e And the voltage v measured by the first voltmeter 73 (see Figure 12) LINK The command i of the current flowing through the DC link section 20 (see Figure 12) is fed back to the DC link section 20. out * Calculate. The distributor 80 receives the current command i out * Current command i1` for each circuit 14-1, 14-2, ... 14-N * i2` * , , , i N ` * Distribute. 【0116】 Controller 104-1 receives the command value i1` distributed by distributor 80 to control circuit 14-1. * Controller 104-1 is controlled using this method. Controller 104-1 obtains the voltage v1 and second current i1 of the power supply for circuit 14-1 from circuit 14-1. Controller 104-1 transmits a control command d1 to control circuit 14-1 based on the obtained voltage v1 and second current i1. Similarly, controller 104-N receives the command value i distributed by distributor 80 to control circuit 14-N. N ` * Controller 104-N is controlled using the power supply voltage v of circuit 14-N. N And the second current i N The voltage v is obtained from circuit 14-N. Controller 104-N receives the obtained voltage v N And the second current i N Based on this, control command d controls circuit 14-N. N Send. 【0117】 Figure 14 is a control block diagram of the control device 104 according to the fourth embodiment. Controller 104-1 comprises a conversion unit 150, a current control unit 120, a non-interference control unit 230, a control command output unit 140, and a command low-frequency unit 144. Controller 104-1 differs from the control unit 102 of the second embodiment (see Figure 5) in that the voltage control unit 210 is located upstream of the distributor 80. Controller 104-1 outputs i1` from the distributor 80. * Based on this, a control command d1 for controlling circuit 14-1 is output. Furthermore, the controller 104-1 differs from the control unit 102 of the second embodiment (see Figure 5) in that the voltage high-frequency unit 143 is located outside the controller 104-1. The voltage high-frequency unit 143 calculates Δv LINK This is output to the non-interference control units 230 of controllers 104-1, 104-2, ..., 104-N. 【0118】 [Modification 1 of the fourth embodiment] In the fourth embodiment, the command value i out * Current command i1` for each circuit 14-1, 14-2, ... 14-N * i2` * , , , i N ` * The current is distributed and controlled for each circuit 14-1, 14-2, ..., 14-N. Therefore, due to the influence of variations in the current detectors in each circuit 14-1, 14-2, ..., 14-N, i out The control characteristics may deteriorate. In this modified example, i out A current detector is provided, and the current of circuit 14-1 is controlled based on the current value calculated by equation (4-1). 【0119】 TIFF0007875535000038.tif7163 【0120】 Here, i k '(where k is an integer from 2 to N) is the current value flowing from each circuit 14-1, 14-2, ... 14-N into the DC link section 20 (see Figure 12), and the current detection values ​​i1, i2, ... i for each circuit 14-1, 14-2, ... 14-N are i1, i2, ... i NThese are values ​​converted appropriately from , 【0121】 Figure 15 is a control block diagram of a modified example 1 of the fourth embodiment. Compared to Modification 1 of the fourth embodiment, this differs in that it includes a converter 450-2, ..., a converter 450-N, and a subtractor 177. The converter 450-2 converts the current detection value i2 detected by the current detector in circuit 14-2 into the current value i2' flowing from circuit 14-2 into the DC link section 20 (see Figure 12). Similarly, the converter 450-N converts the current detection value i detected by the current detector in circuit 14-N into the current value i N The current value i flows from circuit 14-N into the DC link section (see Figure 12). N Convert to '. The subtractor 177 performs subtraction according to equation (4-1). Specifically, the subtractor 177 performs subtraction on the detected i out From this, the current value i2'···i output by the converter 450-2~450-N N The subtractor 177 performs a subtraction operation on each of the '' values. The subtractor 177 outputs the result of the subtraction operation to the current control unit 120. In the modified example 2 of the fourth embodiment, the current control of circuit 14-1 is i out Since current control is performed based on the detected value, the influence of variations in the current detectors of each device may be affected. out This can suppress the deterioration of the control characteristics. 【0122】 [Fifth Embodiment] Figure 16 shows the circuit configuration of the power optimization system 5 according to the fifth embodiment. The power optimization system 5 comprises a solar power generation system 51, an energy storage system 52, a grid-connected inverter 53, and a connector 54. The photovoltaic power generation system 51 comprises a power conditioner (PCS) circuit 15-1 and a solar cell 41. The photovoltaic power generation system 51 is a power generation device in which the amount of power generated by the solar cell 41 is not constant but fluctuates depending on the operating environment. Here, the photovoltaic power generation system 51 may be, for example, a wind power generator or an AC / DC converter. The energy storage system 52 comprises a converter circuit 15-2 and a battery 42. The energy storage system 52 can control the amount of power generated by the battery 42. The connector 54 is a component for detachably connecting and electrically connecting equipment to the DC link section 20. For example, refrigeration equipment and air conditioners are connected to the connector 54. In the example shown in Figure 16, the connector 54 is located on the opposite side of the photovoltaic power generation system 51, with the DC link section 20 in between, but the connector 54 may also be located between the DC link section 20 and the photovoltaic power generation system 51. Also, in the example shown in Figure 16, there is one connector 54, but there may be multiple connectors 54. Note that equipment may also be connected directly to the DC bus without going through the connector 54. In this embodiment, the DC voltage of the DC link section 20 is controlled by the solar power generation system 51 and the energy storage system 52, i out * Current command value i1' of solar power generation system 51 * and the current command value i2' of the energy storage system 52 * It calculates and controls it. 【0123】 Figure 17 is a control block diagram of the control device 105 according to the fifth embodiment. The solar power generation system 51 (see Figure 16) is controlled by MPPT (Maximum Power Point Tracking). MPPT control is a control method that automatically determines the optimal current × voltage value (maximum power point, or optimal operating point) that maximizes the output when the solar cell 41 is generating electricity. Furthermore, the energy storage system 52 (see Figure 16) is controlled by battery control to maximize the use of the power generated by the solar power generation system 51. The distributor 80 receives the command value i1 from the solar power generation system 51 and the energy storage system 52. ** and command value i 2Lo ´ * and command value i 2Hi ´ * It obtains i. out *The distributor 80 obtains the obtained command value i1. ** and command value i 2Lo ´ * and command value i 2Hi ´ * Based on this, the command value i out * Current command value i1' * And the current command value i2' * Distribute it to them. 【0124】 Figure 18 is a flowchart of the current command distribution in the fifth embodiment. The flowchart in Figure 18 shows that in step 1001 i out * ≧i1´ ** +i 2Hi ´ * Determine whether or not. If the answer in step 1001 is YES, proceed to step 1002, i out * i1' ** +i 2Hi ´ * Toshi, i1' * i1' ** Toshi, i2' * to i 2Hi ´ * The process is terminated. Note that if the answer in step 1001 is YES, the PV is at its maximum generated power and the battery is supplying its maximum discharge power. The voltage control input exceeds the supplyable current value. 【0125】 If the answer in step 1001 is NO, proceed to step 1003, i out * ≧i1´ ** +i 2Lo ´ * Determine whether or not this is true. If the answer in step 1003 is YES, proceed to step 1004 and select i1'. * i1' ** Toshi, i2' * to i out ´-i1´ ** The process is then terminated. Note that if the answer in step 1003 is YES, the PV is generating maximum power, and the battery is charging and discharging to make up for the power deficit. 【0126】 If the answer in step 1003 is NO, proceed to step 1005, i out * >i 2Lo Determine whether it is ' or not. If the answer in step 1005 is YES, proceed to step 1006 and select i1'. * to i out * -i 2Lo ´ * Toshi, i2' * to i 2Lo ´ * The process is then terminated. Note that if the answer in step 1005 is YES, the PV is below maximum power (output limited), and the battery is receiving and supplying maximum charge power. 【0127】 If the answer in step 1005 is NO, proceed to step 1007, i out * to i 2Lo ´ * Toshi, i1' * Let i2' be 0. * to i 2Lo ´ * The process is then terminated. Note that if the answer is NO in step 1005, the PV system has stopped generating power (output is limited), and the battery is receiving maximum charge power. 【0128】 [Modification 1 of the Fifth Embodiment] Figure 19 shows a modified example 1 of the fifth embodiment. Modified example 1 is configured in which the voltage of the DC link section 20 is controlled by a solar power generation system 51, an energy storage system 52, and a grid-connected inverter 53. 【0129】 Figure 20 is a control block diagram of a modified example 1 of the fifth embodiment. In the fifth embodiment, the current i e While the system detected the current supplied to the grid-connected inverter 53 and other equipment, in Modification 1, the current i e The difference is that it detects the current supplied to other devices. In Example 5, i eThis includes AC components originating from the grid-connected inverter 53, and if the grid power supply connected to the grid-connected inverter 53 is single-phase, it is necessary to constantly detect AC components with a frequency twice that of the power supply frequency. In modified example 1, i e Since it does not include the current from the solar power generation system 51, the energy storage system 52, or the grid-connected inverter 53, it is not affected by the AC component originating from the solar power generation system 51, the energy storage system 52, or the grid-connected inverter 53, making current detection easier. 【0130】 [Modification 2 of the fifth embodiment] Figure 21 shows a modified example 2 of the fifth embodiment. Modified example 2 is configured to control the voltage of the DC link section 20 using a solar power generation system 51, an energy storage system 52, a grid-connected inverter 53, and a refrigeration device 55. 【0131】 Figure 22 is a control block diagram of a modified example 2 of the fifth embodiment. In the modified example 2 of the fifth embodiment, the voltage of the DC link section 20 is controlled by the refrigeration equipment 55, therefore i e Since it does not include the current from the solar power generation system 51, the energy storage system 52, the grid-connected inverter 53, or the refrigeration equipment 55, it is not affected by the AC component originating from the solar power generation system 51, the energy storage system 52, the grid-connected inverter 53, or the refrigeration equipment 55, making current detection easier. Although Figures 21 and 22 illustrate a refrigeration unit 55, the connected equipment is not limited to a refrigeration unit 55; for example, an air conditioner may also be connected. 【0132】 [Sixth Embodiment] Figure 23 shows the system configuration of the sixth embodiment. The sixth embodiment shows an example of a system configuration in an actual embodiment. The configuration for connecting the solar power generation system 51 and the grid-connected inverter 53 via a DC bus and detecting the current is also contained within a single power conditioner (PCR) 57. Voltage control within the DC bus is performed within the PCR. In this embodiment, the power conditioner 57 includes the solar power generation system 51 and the grid-connected inverter 53, but the power conditioner 57 may also include the energy storage system 52. 【0133】 [Effects] The control device 101 of this embodiment is connected to a DC link section 20 equipped with a capacitor 35, and controls a converter 30 that transmits and receives power from the DC link section 20. The control device 101 detects the value i of the first current flowing from the capacitor 35 to other equipment 50 other than the converter 30 connected to the DC link section 20. e A first ammeter 71 for obtaining the voltage, a first voltmeter 73 for detecting the voltage across capacitor 35, and voltage v LINK The detected value and the detected value of the first current i e The device includes a voltage control unit 110 that adjusts the second current transmitted and received by the converter 30 to the DC link section 20. In this case, in a device that receives and supplies DC power to a DC link section 20 to which two or more devices are connected, interference between the two or more devices in the voltage control of the DC link section 20 can be suppressed. In this embodiment, the control device 101, specifically the voltage control unit 110, uses the detected voltage of the DC link unit 20 to set the command value i of the first current. e * Calculate the command value i of the first current. e * and the detected value i of the first current e The difference between these two values ​​is used to adjust the second current i1 that the converter 30 transmits and receives power from the DC link section 20. In this case, interference between devices can be suppressed without using information from other devices. In this embodiment, the control device 101 includes a converter 30 with a switch unit 31, a second ammeter 72, and a control command d1 that controls the switch unit 31. *The output is generated, and using the detected value of the second ammeter 72, the high-frequency component Δi1 of the second current i1 is calculated, and using the detected value of the first voltmeter 73, the high-frequency component Δv of the voltage is calculated. LINK Calculate and control command d1 * Using this, the low-frequency component D1 of the control command * The first manipulated variable Δv is calculated using the high-frequency component Δi1 of the second current i1. L1 * The high-frequency component of the voltage is used to calculate the interference amount Δv LINK Calculate the first manipulated variable Δv L1 * And the interference amount Δv LINK And the low-frequency component D1 of the control command * Using this, a new control command d1 * This is calculated. In this case, interference via the DC link section 20 can be canceled out with a simple calculation. The power conditioner of this embodiment comprises a DC link section 20 equipped with a capacitor 35, a photovoltaic power generation system 51 connected to the DC link section 20 and equipped with a converter controlled by a control device, and a grid-connected inverter 53 configured to be connectable to a grid power supply 43 and connected to the DC link section 20. In this case, in devices that receive and supply DC power to the DC link section 20 to which two or more devices are connected, interference between two or more devices in the voltage control of the DC bus can be suppressed. The heat pump system of this embodiment includes a DC link unit 20 equipped with a capacitor 35, a photovoltaic power generation system 51 equipped with a converter connected to the DC link unit 20, a refrigeration unit 55 connected to the DC link unit 20, and a grid-connected inverter 53 configured to be connectable to a grid power supply 43 and connected to the DC link unit 20. The control device is configured to control the converter or the refrigeration unit 55. In this case, in equipment that receives and supplies DC power to a DC bus to which two or more devices are connected, interference between two or more devices in the voltage control of the DC bus can be suppressed. Furthermore, the control device 101 of this embodiment can control not only power conditioners and heat pump systems, but also equipment connected via a common DC bus. The control device 101 can be applied, for example, to electric vehicles (EVs), uninterruptible power supply (UPS) devices in data centers, and energy management systems. [Explanation of symbols] 【0134】 1...Power optimization system, 20...DC link section, 11...Controlled object, 30...Converter, 31...Switch section, 32...Reactor, 33...Resistor, 35...Capacitor, 40...Power supply, 50...Equipment, 61...Converter circuit, 71...First ammeter, 72...Second ammeter, 73...First voltmeter, 74...Second voltmeter, 75...Second ammeter, 80...Distributor, 100...Control device, 101...Control device, 110...Voltage control section, 130...Non-interference control section, 140...Control command output section, 141...First current high frequency section, 142...Second current high frequency section, 143...Voltage high frequency section, 144...Control command low frequency section, 150...Conversion section

Claims

[Claim 1] A control device connected to a DC link section to which three or more devices are connected and which is equipped with a capacitor, and which controls one or more devices that transmit and receive power to the DC link section, The control device is A first current value acquisition unit acquires the sum of the currents flowing from the capacitor to all devices other than the one or more devices connected to the DC link section, as a first current value, A voltage value acquisition unit that acquires a detected value of the voltage of the aforementioned capacitor, An adjustment unit that adjusts the second current transmitted and received by one or more devices to the DC link section using the detected voltage value and the detected first current value, A control device equipped with the following features. [Claim 2] The control device includes a second current value acquisition unit that acquires the detected value of the second current, The adjustment unit is, Using the detected voltage, the target value of the second current is calculated. The second current is adjusted using the difference between the target value of the second current and the detected value of the second current. The control device according to claim 1. [Claim 3] A control device connected to a DC link section equipped with a capacitor, which controls the equipment that transmits and receives power to the DC link section, The control device is A first current value acquisition unit that acquires a detected value of the first current flowing from the capacitor to equipment other than the equipment connected to the DC link section, The equipment includes a second current value acquisition unit that acquires a detected value of the second current that the equipment transmits and receives power from with the DC link unit, A voltage value acquisition unit that acquires a detected value of the voltage of the aforementioned capacitor, An adjustment unit that adjusts the second current using the detected voltage value and the detected first current value, Equipped with, The aforementioned device includes a power conversion circuit, The adjustment unit is, Outputs a control command to control the power conversion circuit, Using the detected value of the second current, the high-frequency component of the second current is calculated. Using the detected voltage, the high-frequency component of the voltage is calculated. Using the aforementioned control command, the low-frequency component of the control command is calculated. The first manipulated variable is calculated using the high-frequency component of the second current. The interference amount is calculated using the high-frequency component of the aforementioned voltage. A new control command is calculated using the first manipulated variable, the interference amount, and the low-frequency component of the control command. Control device. [Claim 4] A control device according to claim 1 or 3, A DC link section equipped with a capacitor, A converter connected to the DC link section and controlled by the control device, A grid-connected inverter configured to be connectable to a grid power supply and connected to the DC link section, A power conditioner equipped with [feature]. [Claim 5] A control device according to claim 1 or 3, A DC link section equipped with a capacitor, A converter connected to the aforementioned DC link section, The refrigeration equipment connected to the aforementioned DC link section, It comprises a grid-connected inverter configured to be connectable to a grid power supply and connected to the DC link section, The control device is configured to control the converter or the refrigeration equipment. Heat pump system. [Claim 6] The control device is The DC link section controls two or more devices that transmit and receive power. The device includes a second current value acquisition unit that acquires the detected value of the second current of each of the two or more devices. The adjustment unit is, Using the detected voltage, the current command is calculated. The current command is distributed to the target value of the second current of each of the two or more devices. The control device according to claim 1.

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