WO2013189297A1 - 一种电流互感器 - Google Patents

一种电流互感器 Download PDF

Info

Publication number
WO2013189297A1
WO2013189297A1 PCT/CN2013/077581 CN2013077581W WO2013189297A1 WO 2013189297 A1 WO2013189297 A1 WO 2013189297A1 CN 2013077581 W CN2013077581 W CN 2013077581W WO 2013189297 A1 WO2013189297 A1 WO 2013189297A1
Authority
WO
WIPO (PCT)
Prior art keywords
coil
winding
auxiliary
turns
secondary coil
Prior art date
Application number
PCT/CN2013/077581
Other languages
English (en)
French (fr)
Inventor
陈德才
Original Assignee
Chen Decai
Priority date (The priority date is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the date listed.)
Filing date
Publication date
Application filed by Chen Decai filed Critical Chen Decai
Publication of WO2013189297A1 publication Critical patent/WO2013189297A1/zh

Links

Classifications

    • H—ELECTRICITY
    • H01—ELECTRIC ELEMENTS
    • H01F—MAGNETS; INDUCTANCES; TRANSFORMERS; SELECTION OF MATERIALS FOR THEIR MAGNETIC PROPERTIES
    • H01F38/00—Adaptations of transformers or inductances for specific applications or functions
    • H01F38/20—Instruments transformers
    • H01F38/22—Instruments transformers for single phase ac
    • H01F38/28—Current transformers
    • H—ELECTRICITY
    • H01—ELECTRIC ELEMENTS
    • H01F—MAGNETS; INDUCTANCES; TRANSFORMERS; SELECTION OF MATERIALS FOR THEIR MAGNETIC PROPERTIES
    • H01F27/00—Details of transformers or inductances, in general
    • H01F27/34—Special means for preventing or reducing unwanted electric or magnetic effects, e.g. no-load losses, reactive currents, harmonics, oscillations, leakage fields
    • H01F27/38—Auxiliary core members; Auxiliary coils or windings

Definitions

  • the invention belongs to the technical field of electrical measuring instruments, and particularly relates to a current transformer. Background technique
  • the current transformer is a widely used electrical measuring instrument, which is widely used in industrial field equipment, power system primary protection and control loops.
  • the basic performance requirements of current transformers are high measurement accuracy.
  • a conventional current transformer is composed of a magnetic core 1, a primary coil 3, and a secondary coil 4.
  • a current flows through the primary coil, an electric potential is induced in the secondary coil due to electromagnetic induction
  • the load resistor 6 is connected to the coil 4
  • a secondary current is generated in the secondary coil 4.
  • a signal voltage is generated across the load resistor 6, and the signal voltage is proportional to the flow.
  • the coil terminal marked with "*" is the same name end of the primary coil 3 or the secondary coil 4.
  • the current transformer Due to the magnetic reluctance of the magnetic core, the current transformer must consume a small amount of current for excitation during the process of transforming the current, so that the magnetic core is magnetized, thereby generating an induced potential and a secondary current in the secondary coil, and the current transformer
  • the measurement error is caused by the excitation current consumed by the core.
  • the ratio difference and phase angle difference of the current transformer increase with the decrease of the primary current.
  • the commonly used compensation methods are fractional ⁇ compensation, magnetic shunt compensation, etc., but the compensated measurement The accuracy is still low.
  • Chinese patent document CN201549350U discloses a current transformer laminated core magnetic shunt compensation device, which comprises a laminated upper core, a laminated lower core, a secondary winding, a magnetic shunt compensation winding, and a secondary winding. Wrap around the laminated upper core and the laminated lower core, the magnetic shunt compensation winding is wound on the laminated upper core, and the secondary winding and the magnetic shunt compensation winding are connected in series, using the laminated iron The nonlinearity of the core magnetic performance compensates the measurement accuracy of the current transformer. The compensation amount depends on the magnetic properties of the laminated core and the number of turns of the magnetic shunt compensation winding. The measurement of the current transformer after the magnetic shunt compensation is used. The accuracy has been greatly improved, but the measurement accuracy after compensation is still low.
  • the invention provides a current transformer with high measurement accuracy.
  • a current transformer includes a main magnetic core, an auxiliary magnetic core, a primary coil, a secondary coil, an auxiliary coil, a load resistor connected at both ends of the secondary coil, a detecting resistor connected at both ends of the auxiliary coil, and a detecting resistor
  • the ratio of the resistance value to the resistance of the load resistor is equal to the ratio of the number of turns of the auxiliary coil to the number of turns of the secondary coil, the primary coil and the secondary coil Winded on the main core and the auxiliary core, the auxiliary coil is wound on the auxiliary core, and the non-named end of the auxiliary coil is connected with the same end of the secondary coil, and the two ends of the primary coil are current input ends, and the auxiliary coil
  • the same name end and the non-identical end of the secondary coil are signal output ends; or, the same name end of the auxiliary coil and the two ends of the secondary coil are signal output ends, and are used when the output of the current transformer is required to be a three-terminal output signal.
  • the first-stage current transformer is composed of a primary core, a primary coil, a secondary coil, and a load resistor.
  • the second-stage current transformer is constituted by the auxiliary magnetic core, the primary coil, the secondary coil, the auxiliary coil, and the detecting resistor.
  • the first-order current transformer there are the following equations:
  • Np - the number of turns of the secondary coil
  • Ns number of turns of the secondary coil
  • Ip current in the primary coil
  • Izl excitation current of the main core
  • R01 impedance of the secondary coil
  • the measurement error of the first-stage current transformer is: el, and is a negative value.
  • Nf number of turns of the auxiliary coil
  • Iz2 excitation current of the auxiliary core
  • E2 induced potential on the auxiliary coil
  • Z2 excitation impedance of the auxiliary core
  • R02 impedance of the auxiliary coil
  • Rf detection resistance
  • the measurement error of the Class 2 current transformer is: e2, and is a negative value.
  • the voltage between the end of the same name of the auxiliary coil and the non-identical end of the secondary coil is:
  • the measurement error of the current transformer is: e, and is a negative value.
  • the measurement error e of the current transformer is the product of the measurement error el of the first-stage current transformer and the measurement error e2 of the second-stage current transformer. Therefore, the measurement error e of the current transformer and the measurement of the first-stage current transformer The error el is much smaller compared.
  • the core of the 2-stage current transformer can use a core with a small cross-sectional area, that is, the cross-sectional area of the auxiliary core can be smaller than the cross-sectional area of the main core, thereby reducing the material usage of the current transformer and reducing the manufacturing of the current transformer. cost.
  • a current transformer comprising a main magnetic core, n auxiliary magnetic cores, a primary coil, a secondary coil, n auxiliary coils, a load resistor connected at both ends of the secondary coil, and two connected to the first auxiliary coil a first detecting resistor at the end, a second detecting resistor connected to both ends of the second auxiliary coil, and an nth detecting resistor connected to both ends of the nth auxiliary coil, n
  • the ratio of the resistance of the first sense resistor to the resistance of the load resistor is equal to the ratio of the number of turns of the first auxiliary coil to the number of turns of the secondary coil
  • the resistance and load of the second sense resistor The ratio of the resistance of the resistor is equal to the ratio of the number of turns of the second auxiliary coil to the number of turns of the secondary coil, and so on, until the ratio of the resistance of the nth sense resistor to the resistance of the load resistor is equal to the value of the nth auxiliary coil
  • the primary coil and the secondary coil are wound on the main core and the first auxiliary core to the nth auxiliary core, and the first auxiliary coil is wound on the first auxiliary core to the nth auxiliary core, and the second auxiliary coil Winding on the second auxiliary core to the nth auxiliary core, and so on, until the nth auxiliary winding is wound on the nth auxiliary core;
  • the same-name end of the secondary coil is connected to the non-identical end of the first auxiliary coil, the same-name end of the first auxiliary coil is connected to the non-identical end of the second auxiliary coil, and so on, until the same name of the n-1th auxiliary coil The end is connected to the non-identical end of the nth auxiliary coil;
  • Both ends of the primary coil are current input ends, and the same name end of the nth auxiliary coil and the non-identical end of the secondary coil are signal output ends; or, the same name end of the nth auxiliary coil and both ends of the secondary line book ring are signals
  • the output is used when the output of the current transformer is required to be a three-terminal output signal.
  • the first-stage current transformer is composed of a primary core, a primary coil, a secondary coil, and a load resistor.
  • the first auxiliary magnetic core, the primary coil, the secondary coil, the first auxiliary coil, and the first detecting resistor constitute a second-stage current transformer.
  • the third auxiliary current transformer, the primary coil, the secondary coil, the first auxiliary coil to the second auxiliary coil, and the second detecting resistor constitute a third-stage current transformer.
  • the n+1th auxiliary current core, the primary coil, the secondary coil, the first auxiliary coil to the nth auxiliary coil, and the nth detecting resistor constitute an n+1th level current transformer.
  • Np - the number of turns of the secondary coil
  • Ns the number of turns of the secondary coil
  • Ip current in the primary coil
  • Iz l excitation current of the main core
  • R01 impedance of the secondary coil
  • R load resistance
  • the measurement error of the first-stage current transformer is: el, and is a negative value.
  • Nfl number of turns of the first auxiliary coil
  • Iz2 excitation current of the first auxiliary core
  • E2 an induced potential on the first auxiliary coil
  • R02 impedance of the first auxiliary coil
  • Rfl the first detecting resistor
  • the measurement error of the Class 2 current transformer is: e2, and is a negative value.
  • Nfn the number of turns of the nth auxiliary coil
  • I (n+1) the current in the nth auxiliary coil
  • Iz(n+1) excitation current of the nth auxiliary core
  • E(n+1) an induced potential on the nth auxiliary coil
  • Z(n+1) excitation impedance of the nth auxiliary core
  • R0 (n+1) impedance of the nth auxiliary coil
  • Rfn nth sense resistor
  • I (n+1) (Np/Nfn)*Ip*el*e2*'"* [ 1-e (n+1) ]
  • e (n+l) ⁇ [R0 (n+l) + Rfn] /Z (n+1) ⁇ / ⁇ 1 + [R0 (n+1) + Rfn) ] /Z (n+1) ⁇
  • the measurement error of the (n+1)th current transformer is: e (n+l), and is a negative value.
  • the ratio of the resistance of the first detecting resistor to the resistance of the load resistor is equal to the ratio of the number of turns of the first auxiliary coil to the number of turns of the secondary coil
  • the ratio of the resistance of the second detecting resistor to the resistance of the load resistor is equal to The ratio of the number of turns of the second auxiliary coil to the number of turns of the secondary coil, and so on, until the ratio of the resistance of the nth sense resistor to the resistance of the load resistor is equal to the number of turns of the nth auxiliary coil and the secondary coil
  • the ratio of the number of turns says, therefore:
  • the voltage between the end of the same name of the nth auxiliary coil and the non-identical end of the secondary coil is:
  • the measurement error of the current transformer is: e, and is a negative value.
  • the measurement error e of the current transformer is the product of the measurement error el of the first-stage current transformer and the measurement error e2 of the second-stage current transformer up to the measurement error e (n+1) of the n+1-th current transformer. Therefore, the measurement error e of the current transformer is much smaller than the measurement error el of the first-stage current transformer.
  • the current transformer comprises a main magnetic core, a first auxiliary magnetic core, a second auxiliary magnetic core, a primary coil, a secondary coil, a first auxiliary coil, a second auxiliary coil, and a secondary coil.
  • the ratio of the number of turns of the coil to the number of turns of the secondary coil, the ratio of the resistance of the second sense resistor to the resistance of the load resistor is equal to the ratio of the number of turns of the second auxiliary coil to the number of turns of the secondary coil;
  • the secondary coil is wound on the main core, the first auxiliary core, and the second auxiliary core, the first auxiliary coil is wound on the first auxiliary core and the second auxiliary core, and the second auxiliary winding is wound on The second auxiliary core is connected; the same name end of the secondary coil is connected to the non-identical end of the first auxiliary coil, and the same end of the first auxiliary coil is connected to the non-identical end of the second auxiliary coil; Current input, the same as the second auxiliary
  • the voltage between the same-name end of the second auxiliary coil and the non-identical end of the secondary coil is:
  • the measurement error of the current transformer is: e, and is a negative value.
  • the measurement error e of the current transformer is the product of the measurement error el of the first-stage current transformer and the measurement error e2 of the second-stage current transformer and the measurement error difference e3 of the third-stage current transformer, and therefore, the current mutual inductance
  • the measurement error e of the device is much smaller than the measurement error el of the first-stage current transformer.
  • a current transformer includes: a main core book, an auxiliary core, a primary coil, a secondary coil, an auxiliary coil, and a primary coil and a secondary coil are wound on the main core and the auxiliary core, and auxiliary The coil is wound on the auxiliary magnetic core; the two ends of the primary coil are current input ends, and the two ends of the auxiliary coil and the two ends of the secondary coil are signal output ends; or, the same name of the auxiliary coil and the second name of the secondary coil The end phase is connected; the same name end of the auxiliary coil and the two ends of the secondary coil are signal output ends.
  • the non-identical end of the auxiliary coil of the current transformer and the same-name end of the secondary coil are not connected, it should be connected in an external circuit, and the two ends of the secondary coil of the current transformer are connected with the load resistance in the external circuit.
  • both ends of the auxiliary coil of the current transformer are connected to the detecting resistor in the external circuit, and the ratio of the resistance of the selected detecting resistor to the resistance of the load resistor is equal to the number of turns of the auxiliary coil and the number of turns of the secondary coil
  • the ratio between the end of the auxiliary coil and the non-identical end of the secondary coil is:
  • Np the number of turns of the primary coil
  • Ns the number of turns of the secondary coil
  • Ip current in the primary coil
  • the measurement error of the current transformer is: e, and is a negative value.
  • the measurement error e of the current transformer is the product of the measurement error el of the first-stage current transformer and the measurement error e2 of the second-stage current transformer. Therefore, the measurement error e of the current transformer and the measurement of the first-stage current transformer The error el is much smaller compared.
  • the cross-sectional area of the auxiliary core can be smaller than the cross-sectional area of the main core, thereby reducing the material usage of the current transformer and reducing the manufacturing cost of the current transformer.
  • a current transformer comprising a main magnetic core, n auxiliary magnetic cores, primary coils, secondary coils, n auxiliary coils, n being an integer greater than or equal to 2, primary coil and secondary coil wound On the main magnetic core and the first auxiliary magnetic core to the nth auxiliary magnetic core, the first auxiliary winding is wound on the first auxiliary magnetic core to the nth auxiliary magnetic core, and the second auxiliary winding is wound on the second auxiliary magnetic core Up to the nth auxiliary core, and so on, until the nth auxiliary coil is wound on the nth auxiliary core; the same name end of the secondary coil is connected to the non-identical end of the first auxiliary coil, the first auxiliary The same-name end of the coil is connected to the non-identical end of the second auxiliary coil, and so on, until the same-name end of the n-1 auxiliary coil is connected to the non-identical end of the n-th auxiliary coil; the two ends of the primary coil are current inputs At the end,
  • both ends of the secondary coil of the current transformer are connected to the load resistance in the external circuit, the same name end of the secondary coil of the current transformer and the same name end of the first auxiliary coil and the first detecting resistor in the external circuit Connected, the same name end of the first auxiliary coil of the current transformer and the same name end of the second auxiliary coil are connected to the second detecting resistor in the external circuit, and so on, until the n-1th auxiliary coil of the current transformer The same name end of the same name end and the nth auxiliary coil are connected to the nth detecting resistor in the external circuit;
  • the ratio of the resistance of the first detecting resistor to the resistance of the load resistor is equal to the ratio of the number of turns of the first auxiliary coil to the number of turns of the secondary coil
  • the ratio of the resistance of the second detecting resistor to the resistance of the load resistor is equal to The ratio of the number of turns of the second auxiliary coil to the number of turns of the secondary coil, and so on, until the ratio of the resistance of the nth sense resistor to the resistance of the load resistor is equal to the number of turns of the nth auxiliary coil and the secondary coil
  • the measurement error of the current transformer is: e, and is a negative value.
  • the measurement error e of the current transformer is the product of the measurement error el of the first-stage current transformer and the measurement error e2 of the second-stage current transformer up to the measurement error e (n+1) of the n+1-th current transformer. Therefore, the measurement error e of the current transformer is much smaller than the measurement error el of the first-stage current transformer.
  • the current transformer comprises a main magnetic core, a first auxiliary magnetic core, a second auxiliary magnetic core, a primary coil, a secondary coil, a first auxiliary coil, a second auxiliary coil, a primary coil and a secondary coil.
  • the coil is wound on the main core and the first auxiliary On the magnetic flux core and the second auxiliary magnetic core, the first auxiliary coil is wound on the first auxiliary core and the second auxiliary core, and the second auxiliary coil is wound on the second auxiliary core; the first auxiliary coil The non-identical end is connected to the same-name end of the secondary coil, and the same-name end of the first auxiliary coil is connected to the non-identical end of the second auxiliary coil; the two ends of the primary coil are current input ends, and the same-name end of the second auxiliary coil, The same name end of the first auxiliary coil and both ends of the secondary coil are signal output ends.
  • both ends of the secondary coil of the current transformer are connected to the load resistance in the external circuit, the same name end of the secondary coil of the current transformer and the same name end of the first auxiliary coil and the first detecting resistor in the external circuit Connected, the same name end of the first auxiliary coil of the current transformer and the same name end of the second auxiliary coil are connected to the second detecting resistor in the external circuit; when the resistance value of the first detecting resistor and the resistance of the load resistor are selected
  • the ratio is equal to the ratio of the number of turns of the first auxiliary coil to the number of turns of the secondary coil, and the ratio of the resistance of the second sense resistor to the resistance of the load resistor is equal to the number of turns of the second auxiliary coil and the number of turns of the secondary coil
  • the voltage between the same-name end of the second auxiliary line and the non-identical end of the secondary coil is:
  • the measurement error of the current transformer is: e, and is a negative value.
  • the measurement error e of the current transformer is the product of the measurement error el of the first-stage current transformer and the measurement error e2 of the second-stage current transformer up to the measurement error e3 of the third-stage current transformer, and therefore, the current transformer
  • the measurement error e is much smaller than the measurement error el of the level 1 current transformer.
  • the magnetic core winding structure is used.
  • a magnetic core separated structure may be used, that is, the coils are respectively wound on the magnetic core, and the magnetic cores of the wound coils are placed together, and the coils are placed as required. Make a connection.
  • a current transformer comprising a main magnetic core, an auxiliary magnetic core, a primary winding first winding, a primary winding second winding, a secondary winding first winding, a secondary winding second winding, an auxiliary winding, and a connection
  • the ratio of the resistance of the detecting resistor to the resistance of the load resistor is equal to that of the auxiliary winding
  • the ratio of the number to the number of turns of the second winding of the secondary coil, the ratio of the number of turns of the first winding of the primary coil to the number of turns of the first winding of the secondary winding is equal to the number of turns of the second winding of the primary coil and the second winding of the secondary winding
  • the same-name end of the first winding of the primary coil is connected to the non-identical end of the second winding of the primary winding, and the same-name end of the first winding of the secondary winding is connected to the non-identical end of the second winding of the secondary winding, and the second winding of the secondary winding
  • the end of the same name is connected to the non-identical end of the auxiliary coil;
  • the non-identical end of the first winding of the primary winding and the second end of the primary winding are the current input end, and the non-identical end of the same name end of the auxiliary coil and the first winding of the secondary coil is the signal output end; or, the same name of the auxiliary coil
  • the same name end of the second winding of the secondary winding and the non-identical end of the first winding of the secondary winding are signal output ends, when the current transformer is required to be input Used when it is a three-terminal output signal.
  • the primary magnetic core, the primary winding first winding, the secondary winding first winding, the secondary winding second winding, and the load resistor constitute a first-stage current transformer.
  • the second-stage current transformer is composed of the auxiliary magnetic core, the primary winding second winding, the secondary winding second winding, the auxiliary winding, and the detecting resistor.
  • Npl/Nsl Np2/Ns2
  • Npl the number of turns of the first winding of the primary coil
  • Nsl the number of turns of the first winding of the secondary coil
  • Np2 the number of turns of the second winding of the primary coil
  • Ns2 the number of turns of the second winding of the secondary coil
  • Nf the number of turns of the auxiliary coil
  • Ip current in the first winding of the primary coil and the second winding of the primary winding
  • Izl excitation current of the main core
  • Iz2 excitation current of the auxiliary core
  • E1 the induced potential on the first winding of the secondary coil
  • R01 total coil impedance of the first winding of the secondary coil and the second winding of the secondary winding
  • R02 impedance of the auxiliary coil
  • the voltage between the end of the same name of the auxiliary coil and the non-identical end of the first winding of the secondary winding is:
  • the measurement error of the current transformer is: e, and is a negative value.
  • the measurement error e of the current transformer is the product of the measurement error el of the first-stage current transformer and the measurement error e2 of the second-stage current transformer. Therefore, the measurement error e of the current transformer and the measurement of the first-stage current transformer The error el is much smaller compared.
  • the second-stage current transformer is used for detecting the current (Ip*el), since the current (Ip*el) is much smaller than the current Ip in the input primary coil of the first-stage current transformer, therefore, the second stage
  • the magnetic core of the current transformer can use a magnetic core with a smaller cross-sectional area, that is, the cross-sectional area of the auxiliary magnetic core can be smaller than the cross-sectional area of the main magnetic core, thereby reducing the material usage of the current transformer and reducing the manufacturing cost of the current transformer.
  • a current transformer comprising a main magnetic core, n auxiliary magnetic cores, primary winding first winding, primary winding second winding, secondary winding first winding, secondary winding second winding, n auxiliary a coil, a load resistor connected to the non-identical end of the first winding of the secondary winding, and a load resistor of the same name of the second winding of the secondary winding, a first detecting resistor connected to both ends of the first auxiliary coil, and a second connecting end connected to the second auxiliary coil Detecting the resistance until the nth sense resistor connected across the nth auxiliary coil, n being an integer greater than or equal to 2;
  • the ratio of the resistance of the first detecting resistor to the resistance of the load resistor is equal to the ratio of the number of turns of the first auxiliary coil to the number of turns of the second winding of the secondary winding, and the resistance of the second detecting resistor and the resistance of the load resistor.
  • the ratio is equal to the ratio of the number of turns of the second auxiliary coil to the number of turns of the second winding of the secondary winding, and so on, until the ratio of the resistance of the nth sense resistor to the resistance of the load resistor is equal to the number of turns of the nth auxiliary coil
  • the ratio of the number to the number of turns of the first winding of the secondary coil is equal to the ratio of the number of turns of the second winding of the primary winding to the number of turns of the second winding of the secondary winding;
  • the first winding of the primary coil and the first winding of the secondary winding are wound on the main core, and the second winding of the primary coil and the second winding of the secondary winding are wound on the first auxiliary core to the nth auxiliary core, first
  • the auxiliary coil is wound on the first auxiliary magnetic core to the nth auxiliary magnetic core
  • the second auxiliary winding is wound on the second auxiliary magnetic core to the nth auxiliary magnetic core, and so on, until the nth auxiliary winding is wound On the nth auxiliary magnetic core;
  • the same-name end of the first winding of the primary coil is connected to the non-identical end of the second winding of the primary winding
  • the same-name end of the first winding of the secondary winding is connected to the non-identical end of the second winding of the secondary winding
  • the second winding of the secondary winding The end of the same name is connected to the non-identical end of the first auxiliary coil
  • the end of the first auxiliary coil is connected to the non-identical end of the second auxiliary coil, and so on, until the same name end and the nth auxiliary of the n-1th
  • the non-speaking end of the coil is connected;
  • the non-identical end of the first winding of the primary winding and the second end of the primary winding are the current input end, and the non-identical end of the n-th auxiliary coil and the non-identical end of the second winding of the secondary winding are signal book outputs; or,
  • the same name end of the auxiliary coil, the non-identical end of the first winding of the secondary winding, and the same end of the second winding of the secondary winding are signal output ends, which are used when the output of the current transformer is required to be a three-terminal output signal.
  • the primary magnetic core, the primary winding first winding, the secondary winding first winding, the secondary winding second winding, and the load resistor constitute a first-stage current transformer.
  • the second auxiliary current transformer, the primary winding second winding, the secondary winding second winding, the first auxiliary winding, and the first detecting resistor constitute a second-stage current transformer.
  • the third auxiliary current core, the primary winding second winding, the secondary winding second winding, the first auxiliary winding, the second auxiliary winding, and the second detecting resistor constitute a third-stage current transformer.
  • the nth auxiliary magnetic core, the primary winding second winding, the secondary winding second winding, the first auxiliary winding, the nth auxiliary winding, and the nth detecting resistor constitute an n+1th current transformer.
  • Npl/Ns l Np2/Ns2
  • Npl the number of turns of the first winding of the primary coil
  • Nsl the number of turns of the first winding of the secondary coil
  • Np2 the number of turns of the second winding of the primary coil
  • Ns2 the number of turns of the second winding of the secondary coil
  • Nfl the number of turns of the first auxiliary coil
  • Ip current in the first winding of the primary winding and the second winding of the primary winding
  • Izl excitation current of the main core
  • Iz2 excitation current of the first auxiliary core
  • E1 the induced potential on the first winding of the secondary coil
  • R01 total coil impedance of the first winding of the secondary coil and the second winding of the secondary winding
  • R02 the coil impedance of the first auxiliary core
  • Rfl the first detecting resistor
  • Nfn the number of turns of the nth auxiliary coil
  • Kn+l current in the nth auxiliary coil
  • Iz(n+1) excitation current of the nth auxiliary core
  • E(n+1) an induced potential on the nth auxiliary coil
  • R0(n+1) the coil impedance of the nth auxiliary core
  • Rfn nth sense resistor
  • I (n+1) (Np/Nfn)*Ip*el*e2* * [l_e (n+1) ]
  • e(n+l) ⁇ [R0(n+l) + Rfn] /Z (n+1) ⁇ / ⁇ 1 + [R0(n+1) + Rfn) ] /Z (n+1) ⁇
  • the measurement error of the (n+1)th current transformer is: say e(n+l), and is a negative value.
  • the ratio of the resistance value of the first detecting resistor to the resistance value of the load resistor is equal to the ratio of the number of turns of the first auxiliary coil to the number of turns of the secondary coil, and the ratio of the resistance value of the second detecting resistor to the book resistance value of the load resistor Is equal to the ratio of the number of turns of the second auxiliary coil to the number of turns of the secondary coil, and so on, until the ratio of the resistance of the nth sense resistor to the resistance of the load resistor is equal to the number of turns of the nth auxiliary coil and the secondary coil
  • the ratio of the number of turns so there are:
  • the voltage between the end of the same name of the nth auxiliary coil and the non-identical end of the secondary coil is:
  • the measurement error of the current transformer is: e, and is a negative value.
  • the measurement error e of the current transformer is the product of the measurement error el of the first-stage current transformer and the measurement error e2 of the second-stage current transformer up to the measurement error e (n+1) of the n+1-th current transformer. Therefore, the measurement error e of the current transformer is much smaller than the measurement error el of the first-stage current transformer.
  • the current transformer comprises a main magnetic core, a first auxiliary magnetic core, a second auxiliary magnetic core, a primary winding first winding, a primary winding second winding, a secondary winding first winding, and a second a second winding of the coil, a first auxiliary coil, a second auxiliary coil, a load resistor connected to the same end of the second winding of the secondary winding, and a second end of the secondary winding, and a first resistor connected to the first end of the first auxiliary coil a detection resistor and a second detection resistor connected to both ends of the second auxiliary coil; a ratio of a resistance value of the first detection resistor to a resistance value of the load resistor is equal to a number of turns of the first auxiliary coil and a second winding of the secondary coil The ratio of the number of turns, the ratio of the resistance of the second detecting resistor to the resistance of the load resistor is equal to the ratio of the number of turns of the second auxiliary coil
  • the first winding of the primary coil and the first winding of the secondary winding are wound on the main core, and the second winding of the primary coil and the second winding of the secondary winding are wound on the first auxiliary core and the second auxiliary core, first The auxiliary coil is wound on the first auxiliary core and the second auxiliary core, and the second auxiliary coil is wound on the second auxiliary core;
  • the same-name end of the first winding of the primary coil is connected to the non-identical end of the second winding of the primary winding
  • the same-name end of the first winding of the secondary winding is connected to the non-identical end of the second winding of the secondary winding
  • the second winding of the secondary winding The end of the same name is connected to the non-identical end of the first auxiliary coil, and the end of the same name of the first auxiliary coil is connected to the non-identical end of the second auxiliary coil;
  • the non-identical end of the first winding of the primary winding and the same end of the second winding of the primary winding are the current input end, and the non-identical end of the second auxiliary winding and the non-identical end of the second winding of the secondary winding are signal output ends; or, 2
  • the same name end of the auxiliary coil, the non-identical end of the first winding of the secondary coil, and the same end of the second winding of the secondary winding are the signal output terminals, which are used when the output of the current transformer is required to be a three-terminal output signal.
  • the voltage between the same-name end of the second auxiliary winding and the non-identical end of the first winding of the secondary winding is:
  • the measurement error of the current transformer is: e, and is a negative value.
  • the measurement error e of the current transformer is the product of the measurement error el of the first-stage current transformer and the measurement error e2 of the second-stage current transformer and the measurement error e3 of the third-stage current transformer, and therefore, the current transformer
  • the measurement error e is much smaller than the measurement error el of the level 1 current transformer.
  • Solution 7 A current transformer comprising a main magnetic core, an auxiliary magnetic core, a primary winding first winding, a primary winding second winding, a secondary winding first winding, a secondary winding second winding, an auxiliary winding, a primary coil
  • the first winding and the second winding of the secondary winding are wound on the main magnetic core, and the second winding of the primary winding and the second winding of the secondary winding and the second winding of the secondary winding and the auxiliary winding are wound on the auxiliary magnetic core;
  • the same-name end of the first winding of the primary coil is connected to the non-identical end of the second winding of the primary winding, and the same-name end of the first winding of the secondary winding is connected to the non-identical end of the second winding of the secondary winding;
  • the ratio of the number of turns of the first winding of the primary winding to the number of turns of the first winding of the secondary winding is equal to the ratio of the number of turns of the second winding of the primary winding to the number of turns of the second winding of the secondary winding;
  • the non-identical end of the first winding of the primary winding and the second end of the primary winding are the current input end, the two ends of the auxiliary coil and the second end of the second winding of the secondary winding and the non-identical end of the first winding of the secondary coil are Signal output terminal; or, the same name end of the second winding of the secondary coil is connected to the non-identical end of the auxiliary coil, the two ends of the auxiliary coil and the secondary coil
  • the non-identical end of the 1 winding serves as the signal output.
  • the same name end of the second winding of the secondary winding is not connected to the non-identical end of the auxiliary coil, it should be connected in an external circuit, the non-identical end of the first winding of the secondary winding and the second winding of the secondary winding The same name end is connected to the load resistance in the external circuit, and the auxiliary coil is connected to the detecting resistor in the external circuit.
  • the ratio of the resistance of the detecting resistor to the resistance of the load resistor is equal to the number of turns of the auxiliary coil and the secondary coil
  • the voltage between the end of the same name of the auxiliary coil and the non-identical end of the first winding of the secondary winding is:
  • Npl the number of turns of the first winding of the primary coil
  • Nsl the number of turns of the first winding of the secondary coil
  • Ip current of the first winding of the primary coil and the second winding of the primary winding
  • the measurement error of the current transformer is: e, and is a negative value.
  • the measurement error e of the current transformer is the product of the measurement error el of the first-stage current transformer and the measurement error e2 of the second-stage current transformer. Therefore, the measurement error e of the current transformer and the measurement of the first-stage current transformer The error el is much smaller compared.
  • the cross-sectional area of the auxiliary core can be smaller than the cross-sectional area of the main core, thereby reducing the material usage of the current transformer and reducing the manufacturing cost of the current transformer.
  • a current transformer comprising a main magnetic core, n auxiliary magnetic cores, primary winding first winding, primary winding second winding, secondary winding first winding, secondary winding second winding, n auxiliary
  • the coil, n is an integer greater than or equal to 2; the ratio of the number of turns of the first winding of the primary coil to the number of turns of the first winding of the secondary winding is equal to the number of turns of the second winding of the primary coil and the number of turns of the second winding of the secondary winding Ratio
  • the first winding of the primary coil and the first winding of the secondary winding are wound on the main core, and the second winding of the primary winding and the second winding of the secondary winding and the first auxiliary winding are wound from the first auxiliary core to the nth auxiliary magnetic
  • the second auxiliary coil is wound on the second auxiliary core to the nth auxiliary core, and so on, until the nth auxiliary winding is wound on the nth auxiliary core;
  • the same-name end of the first winding of the primary coil is connected to the non-identical end of the second winding of the primary winding, and the same-name end of the first winding of the secondary winding is connected to the non-identical end of the second winding of the secondary winding, and the second winding of the secondary winding
  • the same name end is connected to the non-identical end of the first auxiliary coil, the same end of the first auxiliary coil is connected to the non-identical end of the second auxiliary coil, and so on, until the n-1th auxiliary coil has the same name and the same n non-identical ends of the auxiliary coil are connected;
  • the non-identical end of the first winding of the primary winding and the same end of the second winding of the primary winding are current input terminals, the same-name end of the first auxiliary coil, the same-name end of the second auxiliary coil, the same-name end of the n-th auxiliary coil, and the second The same name end of the second winding of the coil
  • the non-identical end of the first winding of the secondary coil is connected to the load resistance of the external circuit of the non-identical end of the auxiliary coil, and the first auxiliary coil is connected to the first detecting resistor in the external circuit, and the second auxiliary Both ends of the coil are connected to the second detecting resistor in the external circuit, and so on, until the nth auxiliary coil is connected to the nth detecting resistor in the external circuit;
  • the ratio of the resistance of the first detecting resistor to the resistance of the load resistor is equal to the ratio of the number of turns of the first auxiliary coil to the number of turns of the secondary coil
  • the ratio of the resistance of the second detecting resistor to the resistance of the load resistor is equal to The ratio of the number of turns of the second auxiliary coil to the number of turns of the secondary coil, and so on, until the ratio of the resistance of the nth sense resistor to the resistance of the load resistor is equal to the number of turns of the nth auxiliary coil and the secondary coil
  • the voltage between the same name end of the nth auxiliary coil and the non-same name end of the first winding of the secondary winding is:
  • the measurement error of the current transformer is: e, and is a negative value.
  • the measurement error e of the current transformer is the product of the measurement error el of the first-stage current transformer and the measurement error e2 of the second-stage current transformer up to the measurement error e (n+1) of the n+1-th current transformer. Therefore, the measurement error e of the current transformer is much smaller than the measurement error el of the first-stage current transformer.
  • the current transformer comprises a main magnetic core, a first auxiliary magnetic core, a second auxiliary magnetic core, a primary winding first winding, a primary winding second winding, a secondary winding first winding, and a second The second winding of the coil, the first auxiliary coil, and the second auxiliary coil; the ratio of the number of turns of the first winding of the primary winding to the number of turns of the first winding of the secondary winding is equal to the number of turns of the second winding of the primary coil and the second of the secondary winding The ratio of the turns of the winding;
  • the first winding of the primary coil and the first winding of the secondary winding are wound on the main core, and the second winding of the primary coil, the second winding of the secondary winding, and the first auxiliary winding are wound around the first auxiliary core and the second auxiliary magnetic On the core, the second auxiliary coil is wound on the second auxiliary core;
  • the same-name end of the first winding of the primary coil is connected to the non-identical end of the second winding of the primary winding
  • the same-name end of the first winding of the secondary winding is connected to the non-identical end of the second winding of the secondary winding
  • the second winding of the secondary winding The end of the same name is connected to the non-identical end of the first auxiliary coil, and the end of the same name of the first auxiliary coil is connected to the non-identical end of the second auxiliary coil;
  • the non-identical end of the first winding of the primary winding and the second end of the primary winding are the current input end, the same name end of the first auxiliary coil, the same name end of the second auxiliary coil, the same name end of the second winding of the secondary winding, and two The non-identical end of the first winding of the secondary winding is the signal output.
  • the non-identical end of the first winding of the secondary winding and the same end of the second winding of the secondary winding are connected to the load resistance of the external circuit, and the same-name end of the second winding of the secondary winding and the same-name end of the first auxiliary winding Connected to the first detecting resistor in the external circuit, the same-name end of the first auxiliary coil and the same-name end of the second auxiliary coil are connected to the second detecting resistor in the external circuit;
  • the ratio of the resistance of the first detecting resistor to the resistance of the load resistor is equal to the ratio of the number of turns of the first auxiliary coil to the number of turns of the second winding of the secondary winding, the resistance of the second detecting resistor and the resistance of the load resistor The ratio is equal to the ratio of the number of turns of the second auxiliary coil to the number of turns of the second winding of the secondary winding;
  • the voltage between the same-name end of the second auxiliary winding and the non-identical end of the first winding of the secondary winding is:
  • the measurement error of the current transformer is: e, and is a negative value.
  • the measurement error e of the current transformer is the product of the measurement error el of the first-stage current transformer and the measurement error e2 of the second-stage current transformer and the measurement error e3 of the third-stage current transformer, and therefore, the current transformer
  • the measurement error e is much smaller than the measurement error el of the level 1 current transformer.
  • the cross-sectional area of the auxiliary magnetic core is smaller than the cross-sectional area of the main magnetic core, thereby reducing the material usage of the current transformer and reducing the manufacturing cost of the current transformer.
  • the current transformer of the invention has the characteristics of high measurement accuracy.
  • Figure 1 is a schematic diagram of a conventional current transformer.
  • Fig. 2 is a schematic diagram of Embodiment 1 of the present invention.
  • FIG. 3 is a schematic diagram of Embodiment 2 of the present invention.
  • Figure 4 is a schematic diagram of Embodiment 3 of the present invention.
  • FIG. 5 is a schematic diagram of Embodiment 4 of the present invention.
  • Figure 6 is a schematic diagram of Embodiment 5 of the present invention.
  • Figure 7 is a schematic diagram of Embodiment 6 of the present invention.
  • Figure 8 is a schematic diagram of Embodiment 7 of the present invention.
  • Figure 9 is a schematic diagram of Embodiment 8 of the present invention.
  • Figure 10 is a schematic diagram of Embodiment 9 of the present invention.
  • Figure 11 is a schematic diagram of Embodiment 10 of the present invention.
  • Figure 12 is a schematic diagram of Embodiment 11 of the present invention.
  • Figure 13 is a schematic diagram of Embodiment 12 of the present invention.
  • Figure 14 is a schematic diagram of Embodiment 13 of the present invention.
  • Figure 15 is a schematic diagram of Embodiment 14 of the present invention.
  • Figure 16 is a schematic diagram of Embodiment 15 of the present invention.
  • Figure 17 is a schematic diagram of Embodiment 16 of the present invention.
  • Figure 18 is a schematic diagram of Embodiment 17 of the present invention.
  • Figure 19 is a schematic diagram of Embodiment 18 of the present invention.
  • Figure 20 is a schematic diagram of Embodiment 19 of the present invention.
  • Figure 21 is a schematic diagram of Embodiment 20 of the present invention.
  • the current transformer of the embodiment includes: a main magnetic core 1, an auxiliary magnetic core 2, a primary coil 3, a secondary coil 4, an auxiliary coil 5, and a load connected to both ends of the secondary coil 4.
  • the resistor 6 is connected to the detecting resistor 7 at both ends of the auxiliary coil 5.
  • the resistance of the detecting resistor is equal to the resistance of the load resistor
  • the number of turns of the auxiliary coil is equal to the number of turns of the secondary coil
  • the primary coil and the secondary coil are wound around the main magnetic
  • the auxiliary coil is wound on the auxiliary magnetic core
  • the non-identical end of the auxiliary coil is connected with the same end of the secondary coil
  • the two ends of the primary coil are the current input end
  • the non-identical end of the secondary coil is the signal output.
  • the voltage between the end of the same name of the auxiliary coil and the non-identical end of the secondary coil is:
  • the measurement error of the current transformer is the product of the measurement error el of the first-stage current transformer and the measurement error e2 of the second-stage current transformer.
  • the cross-sectional area of the auxiliary core is smaller than the cross-sectional area of the main core.
  • Embodiment 2 As shown in FIG. 3, on the basis of Embodiment 1, the same name end of the secondary coil is added as a signal output end, that is, the same name end of the auxiliary coil, the same name end of the secondary coil, and the secondary coil.
  • the non-identical end is the signal output, which is used when the output of the current transformer is required to be a three-terminal output signal.
  • the current transformer of the embodiment includes: a main magnetic core 1, a first auxiliary magnetic core 2, a second auxiliary magnetic core 8, a primary coil 3, a secondary coil 4, and a first auxiliary coil. 5.
  • the resistance of the first sense resistor is equal to the resistance of the load resistor
  • the resistance of the second sense resistor is equal to the resistance of the load resistor
  • the number of turns of the first auxiliary coil is equal to the number of turns of the secondary coil
  • the number of turns of the second auxiliary coil Equal to the number of turns of the secondary coil
  • the primary coil and the secondary coil are wound on the main core, the first auxiliary core, and the second auxiliary core, the first The auxiliary coil is wound on the first auxiliary core and the second auxiliary core, and the second auxiliary coil is
  • the same-name end of the first auxiliary coil is connected to the non-identical end of the second auxiliary coil, and both ends of the primary coil are current input ends, and the same-name end of the second auxiliary coil and the non-identical end of the secondary coil are signal output ends.
  • the voltage between the same-name end of the second auxiliary coil and the non-identical end of the secondary coil is:
  • the measurement error of the current transformer is the product of the measurement error of the first-stage current transformer el and the measurement error e2 of the second-stage current transformer and the measurement error e3 of the third-stage current transformer.
  • Embodiment 4 As shown in FIG. 5, on the basis of Embodiment 3, the same name end of the secondary coil is added as a signal output end, that is, the same name end of the second auxiliary coil, the same name end of the second auxiliary coil, and The non-identical end of the secondary coil is the signal output terminal, which is used when the output of the current transformer is required to be a three-terminal output signal.
  • Embodiment 5 As shown in FIG. 6, the current transformer book of this embodiment includes: a main magnetic core 1, a first auxiliary magnetic core 2, a second auxiliary magnetic core 8, an n-th auxiliary magnetic core 11, a primary coil 3, The secondary coil 4, the first auxiliary coil 5, the second auxiliary coil 9, the n-th auxiliary coil 12, the load resistor 6 connected to both ends of the secondary coil 4, and the first detecting resistor 7 connected to both ends of the first auxiliary coil 5
  • the second detecting resistor 10 connected to both ends of the second auxiliary coil 9 and the nth detecting resistor 13 connected to both ends of the nth auxiliary coil 12, n is an integer greater than or equal to 2, and the resistance of the first detecting resistor is equal to the load.
  • the resistance value of the resistor, the resistance value of the second detecting resistor is equal to the resistance value of the load resistor, and so on, until the resistance value of the nth detecting resistor is equal to the resistance value of the load resistor, and the number of turns of the first auxiliary coil is equal to that of the secondary coil
  • the number of turns, the number of turns of the second auxiliary coil is equal to the number of turns of the secondary coil, and so on, until the number of turns of the nth auxiliary coil is equal to the number of turns of the secondary coil;
  • the primary coil and the secondary coil are wound around the main core
  • the voltage between the end of the same name of the nth auxiliary coil and the non-identical end of the secondary coil is:
  • the measurement error of the current transformer is the measurement error el of the first-stage current transformer and the measurement error e2 of the second-stage current transformer up to the measurement error e (n+1) of the (n+1)-stage current transformer. product.
  • Embodiment 6 As shown in FIG. 7, on the basis of Embodiment 5, the same name end of the secondary coil is added as a signal output end, that is, the same name end of the nth auxiliary coil, the same name end of the secondary coil, and two The non-identical end of the secondary coil is the signal output, which is used when the output of the current transformer is required to be a three-terminal output signal.
  • the current transformer of the embodiment includes: a main magnetic core 1, an auxiliary magnetic core 2, a primary coil 3,
  • the secondary coil 4, the auxiliary coil 5, the number of turns of the auxiliary coil is equal to the number of turns of the secondary coil, the primary coil and the secondary coil are wound on the main core and the auxiliary core, and the auxiliary coil is wound on the auxiliary core,
  • the same-name end of the secondary coil is connected to the non-identical end of the auxiliary coil, and the two ends of the primary coil are current input ends, and the same-name end of the auxiliary coil and the two ends of the secondary coil are signal output ends.
  • Embodiment 8 As shown in FIG. 9, the current transformer of the embodiment includes: a main magnetic core 1, an auxiliary magnetic core 2, a primary coil 3, a secondary coil 4, and an auxiliary coil 5.
  • the number of turns of the auxiliary coil is equal to the secondary coil.
  • the number of turns, the primary coil and the secondary coil are wound on the main core and the auxiliary core, and the auxiliary coil is wound on the auxiliary core, the two ends of the primary coil are the current input end, the two ends of the auxiliary coil and the second Both ends of the coil are signal outputs.
  • the current transformer of the embodiment includes: a main magnetic core 1, a first auxiliary magnetic core 2, a second auxiliary magnetic core 8, a primary coil 3, a secondary coil 4, and a first auxiliary
  • the number of turns of the first auxiliary coil is equal to the number of turns of the secondary coil
  • the number of turns of the second auxiliary coil is equal to the number of turns of the secondary coil
  • the primary coil and the secondary coil are wound around the main magnetic
  • the first auxiliary magnetic core, and the second auxiliary magnetic core are written, the first auxiliary coil is wound on the first auxiliary core and the second auxiliary core
  • the second auxiliary coil is wound on the second auxiliary core
  • 1 The non-identical end of the auxiliary coil is connected to the same end of the secondary coil, and the same end of the first auxiliary coil is connected to the non-identical end of the second auxiliary coil, and both ends of the primary coil are current input ends, and the second auxiliary coil
  • the same name end the
  • Embodiment 10 As shown in FIG. 11, this embodiment includes: a main magnetic core 1, a first auxiliary magnetic core 2, a second auxiliary magnetic core 8, an n-th auxiliary magnetic core 11, a primary coil 3, and a secondary coil 4.
  • the number is equal to the number of turns of the secondary coil until the number of turns of the nth auxiliary coil is equal to the number of turns of the secondary coil, and the primary coil and the secondary coil are wound on the main core and the first auxiliary core to the nth auxiliary core
  • the first auxiliary coil is wound on the first auxiliary core to the nth auxiliary core
  • the second auxiliary coil is wound on the second auxiliary core to the nth auxiliary core, and so on, until the nth auxiliary coil Winded
  • the two ends of the primary coil are the current input end, the same name end of the first auxiliary coil, the same name end of the second auxiliary coil, the same name end of the nth auxiliary coil, and both ends of the secondary coil are signals Output.
  • the current transformer of the embodiment includes: a main magnetic core 1, an auxiliary magnetic core 2, a primary winding first winding 31, a primary winding second winding 32, a secondary winding first winding 41, The secondary winding second winding 42, the auxiliary coil 5, the load resistor 6 connected to the non-identical end of the secondary winding first winding 41 and the secondary winding 42 of the same name, and the detecting resistor 7 connected to the both ends of the auxiliary winding 5
  • the resistance of the detecting resistor is equal to the resistance of the load resistor.
  • the number of turns of the first winding of the primary coil is equal to the number of turns of the second winding of the primary coil
  • the number of turns of the first winding of the secondary winding is equal to the number of turns of the second winding of the secondary winding.
  • the number of turns of the auxiliary coil is equal to the number of turns of the second winding of the secondary coil
  • the first winding and the secondary winding of the primary winding are the first The winding is wound on the main core
  • the second winding of the primary coil, the second winding of the secondary winding, and the auxiliary winding are wound on the auxiliary magnetic core, and the same name end of the first winding of the primary winding and the non-identical end of the second winding of the primary winding Connected, the same-name end of the first winding of the secondary winding is connected to the non-identical end of the second winding of the secondary winding, and the same-name end of the second winding of the secondary winding is connected to the non-identical end of the auxiliary
  • Embodiment 12 As shown in FIG. 13, in the embodiment, on the basis of Embodiment 11, the same name end of the second winding of the secondary coil is added as a signal output end, that is, the same name end of the auxiliary coil and the second winding of the secondary coil.
  • the non-identical end of the same name end and the first winding of the secondary coil is the signal output end, and is used when the output of the current transformer is required to be a three-terminal output signal.
  • the current transformer of the embodiment includes: a main magnetic core 1, a first auxiliary magnetic core 2, a second auxiliary magnetic core 8, a primary winding first winding 31, and a primary winding second winding.
  • the same-name end of the first winding of the primary coil is connected to the non-identical end of the second winding of the primary winding
  • the same-name end of the first winding of the secondary winding is connected to the non-identical end of the second winding of the secondary winding
  • the second winding of the secondary winding is connected to the same-name end.
  • the same-name end is connected to the non-identical end of the first auxiliary coil
  • the same-name end of the first auxiliary coil is connected to the non-identical end of the second auxiliary coil
  • the same name end is the current input end
  • the same name end of the second auxiliary coil and the non-identical end of the first winding of the secondary coil are signal output ends.
  • Embodiment 14 As shown in FIG. 15, in the embodiment, on the basis of Embodiment 13, the same name end of the second winding of the secondary coil is added as a signal output end, that is, the same name end of the second auxiliary coil, and the second coil second.
  • the same name end of the winding and the non-identical end of the first winding of the secondary winding are signal output ends, which are used when the output of the current transformer is required to be a three-terminal output signal.
  • the current transformer of the embodiment includes: a main magnetic core 1, a first auxiliary magnetic core 2, a second auxiliary magnetic core 8, an n-th auxiliary magnetic core 11, and a primary winding first winding.
  • the primary coil second winding 32, the secondary coil first winding 41, the secondary coil second winding 42, the first auxiliary coil 5, the second auxiliary coil 9, the n-th auxiliary coil 12, and the secondary coil a non-identical end of the winding 41 and a load resistor 6 of the same-numbered end of the second winding 42 of the secondary winding, a first detecting resistor 7 connected to both ends of the first auxiliary coil 5, and a second detecting resistor connected to both ends of the second auxiliary coil 9. 10.
  • the resistance of the first detecting resistor is equal to the resistance of the load resistor
  • the resistance of the second detecting resistor is equal to the resistance of the load resistor until the nth detecting The resistance of the resistor is equal to the load
  • the resistance of the resistance, the number of turns of the first winding of the primary coil is equal to the number of turns of the second winding of the primary coil
  • the number of turns of the first winding of the secondary winding is equal to the number of turns of the second winding of the secondary winding
  • the number of turns of the first auxiliary winding Equal to the number of turns of the second winding of the secondary coil
  • the number of turns of the second auxiliary coil is equal to the number of turns of the second winding of the secondary coil, until the number of turns of the nth auxiliary coil is equal to the number of turns of the second winding of the secondary coil, the primary coil
  • the first winding and the second winding are wound on the main core, and the primary wind
  • the second auxiliary coil is wound on the second auxiliary magnetic core to the nth auxiliary magnetic core until the nth auxiliary winding is wound on the nth auxiliary magnetic core, and the same name end of the first winding of the primary winding and the second winding of the primary winding
  • the non-identical end of the secondary winding is connected, and the same-name end of the first winding of the secondary coil is connected to the non-identical end of the second winding of the secondary winding, and the same-name end of the second winding of the secondary winding is connected to the non-identical end of the first auxiliary winding.
  • the same name end of the auxiliary coil and the non-identical end of the first winding of the secondary coil are signal output ends.
  • Embodiment 16 As shown in FIG. 17, in the embodiment, on the basis of Embodiment 15, the same name end of the second winding of the secondary coil is added as a signal output end, that is, the same name end of the nth auxiliary coil, and the second coil second.
  • the same name end of the winding and the non-identical end of the first winding of the secondary winding are signal output ends, which are used when the output of the current transformer is required to be a three-terminal output signal.
  • Embodiment 17 As shown in FIG. 18, the current transformer of the embodiment includes: a main magnetic core 1, an auxiliary magnetic core 2, a primary winding first winding 31, a primary winding second winding 32, a secondary winding first winding 41,
  • the second coil 42 and the auxiliary coil 5 of the secondary coil have the number of turns of the first winding of the primary coil equal to the number of turns of the second winding of the primary coil, and the number of turns of the first winding of the secondary coil is equal to the number of turns of the second winding of the secondary coil.
  • the number of turns of the auxiliary coil is equal to the number of turns of the second winding of the secondary coil, and the first winding of the primary winding and the first winding of the secondary winding are wound on the main core, the second winding of the primary winding, the second winding of the secondary winding, and the auxiliary
  • the coil is wound on the auxiliary magnetic core, and the same name end of the first winding of the primary coil is connected with the non-identical end of the second winding of the primary coil, and the same name end of the first winding of the secondary winding and the non-identical end of the second winding of the secondary winding Connected, the same name end of the second winding of the secondary coil is connected to the non-identical end of the auxiliary coil, and the non-identical end of the first winding of the primary winding and the same end of the second winding of the primary winding are the current input end, the same as the auxiliary coil
  • Embodiment 18 As shown in FIG. 19, the current transformer of the embodiment includes: a main magnetic core 1, an auxiliary magnetic core 2, a primary winding first winding 31, a primary winding second winding 32, a secondary winding first winding 41,
  • the second coil 42 and the auxiliary coil 5 of the secondary coil have the number of turns of the first winding of the primary coil equal to the number of turns of the second winding of the primary coil, and the number of turns of the first winding of the secondary coil is equal to the number of turns of the second winding of the secondary coil.
  • the number of turns of the auxiliary coil is equal to the number of turns of the second winding of the secondary coil, and the first winding of the primary winding and the first winding of the secondary winding are wound on the main core, the second winding of the primary winding, the second winding of the secondary winding, and the auxiliary
  • the coil is wound on the auxiliary magnetic core, and the same name end of the first winding of the primary coil is connected with the non-identical end of the second winding of the primary coil, and the same name end of the first winding of the secondary winding and the non-identical end of the second winding of the secondary winding Connected, the non-identical end of the first winding of the primary winding and the second end of the primary winding are the current input end, the two ends of the auxiliary coil, the second winding of the secondary winding The non-identical end of the same name end and the first winding of the secondary coil is the signal output end.
  • the current transformer of this embodiment includes: a main magnetic core 1, a first auxiliary magnetic core 2, a second auxiliary magnetic core 8, a primary winding first winding 31, and a primary winding second winding 32.
  • the number of turns of the first winding is equal to the number of turns of the second winding of the secondary winding
  • the number of turns of the first auxiliary coil is equal to the number of turns of the second winding of the secondary coil
  • the number of turns of the second auxiliary winding is equal to the number of turns of the second auxiliary winding.
  • the number of turns, the first winding of the primary coil and the first winding of the secondary winding are wound on the main core, and the second winding of the primary coil, the second winding of the secondary winding, and the first auxiliary winding are wound around the first auxiliary core and 2
  • the second auxiliary coil is wound on the second auxiliary magnetic core, and the same name end of the first winding of the primary coil is connected to the non-identical end of the second winding of the primary coil, and the same end of the first winding of the secondary winding
  • Non-identical name with the second winding of the secondary coil Said phase connection, the same name end of the second winding of the secondary coil is connected to the non-identical end of the first auxiliary coil, the same name end of the first auxiliary coil is connected to the non-identical end of the second auxiliary coil, and the first winding of the primary winding is The same name end of the second winding of the non-identical end and the second winding of the primary winding is the current input end, the same
  • Embodiment 20 As shown in FIG. 21, the current transformer of the embodiment includes: a main magnetic core 1, a first auxiliary magnetic core 2, a second auxiliary magnetic core 8, a nth auxiliary magnetic core 11, and a primary winding first winding. 31.
  • the number of turns is equal to the number of turns of the second winding of the primary coil
  • the number of turns of the first winding of the secondary coil is equal to the number of turns of the second winding of the secondary coil
  • the number of turns of the first auxiliary coil is equal to the number of turns of the second winding of the secondary coil
  • the number of turns of the second auxiliary coil is equal to the number of turns of the second winding of the secondary coil until the number of turns of the nth auxiliary coil is equal to the number of turns of the second winding of the secondary coil, and the first winding of the primary winding and the first winding of the secondary winding are wound On the main core, the primary winding second winding, the secondary winding second winding, and the first auxiliary winding are wound on the first auxiliary core to the nth

Landscapes

  • Engineering & Computer Science (AREA)
  • Power Engineering (AREA)
  • Measuring Instrument Details And Bridges, And Automatic Balancing Devices (AREA)
  • Measurement Of Current Or Voltage (AREA)
  • Transformers For Measuring Instruments (AREA)

Abstract

一种电流互感器，包括主磁芯（1）、辅助磁芯（2）、一次线圈（3）、二次线圈（4）、辅助线圈（5）、连接在二次线圈两端的负载电阻（6）、连接在辅助线圈两端的检测电阻（7），检测电阻的阻值与负载电阻的阻值的比值等于辅助线圈的匝数与二次线圈的匝数的比值，一次线圈和二次线圈绕制于主磁芯和辅助磁芯上，辅助线圈绕制于辅助磁芯上，辅助线圈的非同名端和二次线圈的同名端相连接，一次线圈的两端为电流输入端，辅助线圈的同名端以及二次线圈的非同名端为信号输出端。该电流互感器测量精度高。

Description

说 明 书
种电流互感器 技术领域
本发明属于电工测量仪器技术领域， 具体涉及一种电流互感器。 背景技术
电流互感器是一种用途广泛的电工测量仪器， 其大量应用于工业现场设备、 电力系统一 次保护和控制回路中， 电流互感器基本的性能要求是具有高的测量精度。
参见图 1， 常规的电流互感器由磁芯 1、 一次线圈 3和二次线圈 4构成， 当一次线圈中流 过电流时， 由于电磁感应， 在二次线圈中就会感应出电势， 在二次线圈 4上连接有负载电阻 6， 则在二次线圈 4中产生二次电流， 二次电流流过负载电阻 6时， 在负载电阻 6的两端产生 信号电压， 此信号电压正比于流过一次线圈 3的电流。 图 1中， 标有 " *"的线圈端子为一次 线圈 3或二次线圈 4的同名端。
由于磁芯磁阻的存在， 电流互感器在转变电流的过程中， 必须消耗一小部分电流用于励 磁， 使磁芯磁化， 从而在二次线圈产生感应电势和二次电流， 电流互感器的测量误差就是由 于磁芯所消耗的励磁电流引起的。 在没有进行误差补偿时， 电流互感器的比值差和相角差都 是随着一次电流的减小而增大， 常用的补偿方法有分数匝补偿、 磁分路补偿等， 但补偿后的 测量精度仍然较低。
中国专利文献 CN201549350U公开了一种电流互感器叠片铁芯磁分路补偿装置， 它包括 叠片式上铁芯、 叠片式下铁芯、 二次绕组、 磁分路补偿绕组， 二次绕组绕在叠片式上铁芯和 叠片式下铁芯上， 磁分路补偿绕组绕在叠片式上铁芯上， 二次绕组和磁分路补偿绕组相串联， 利用叠片式上铁芯磁性能的非线性对电流互感器的测量精度进行补偿， 补偿量取决于叠片式 上铁芯的磁性能和磁分路补偿绕组的匝数， 使用磁分路补偿后电流互感器的测量精度均得到 了较大的改善， 但补偿后的测量精度仍然较低。
此外， 中国专利文献 CN87200450U公开了双级低磁通电容补偿电流互感器、 CN1022269C 公开了双辅助偶合补偿电流互感器， 上述技术方案均存在补偿后的测量精度低的缺陷。 发明内容
本发明提供了一种测量精度高的电流互感器。
本发明采用如下多种技术方案：
技术方案一： 一种电流互感器， 包括主磁芯、 辅助磁芯、 一次线圈、 二次线圈、 辅助线 圈、 连接在二次线圈两端的负载电阻、 连接在辅助线圈两端的检测电阻， 检测电阻的阻值与 负载电阻的阻值的比值等于辅助线圈的匝数与二次线圈的匝数的比值， 一次线圈和二次线圈 绕制于主磁芯和辅助磁芯上， 辅助线圈绕制于辅助磁芯上， 辅助线圈的非同名端和二次线圈 的同名端相连接， 一次线圈的两端为电流输入端， 辅助线圈的同名端以及二次线圈的非同名 端为信号输出端； 或者， 辅助线圈的同名端以及二次线圈的两端为信号输出端， 当需要电流 互感器的输出为三端输出信号时使用。
由主磁芯、 一次线圈、 二次线圈和负载电阻构成第 1级电流互感器。
由辅助磁芯、 一次线圈、 二次线圈、 辅助线圈和检测电阻构成第 2级电流互感器。 对于第 1级电流互感器， 有以下方程式：
Ip*Np - Il*Ns - Izl*Ns =0
Izl = El /Zl
El = I1*R01 + I1*R 说
其中： Np: —次线圈的匝数；
Ns: 二次线圈的匝数； 书
Ip: 一次线圈中的电流；
II： 二次线圈中的电流；
Izl: 主磁芯的励磁电流；
E1: 二次线圈上的感应电势；
Z1: 主磁芯的励磁阻抗；
R01: 二次线圈的阻抗；
R: 负载电阻；
求解以上方程式， 则可得到：
Il=(Np/Ns)*Ip* (1-el)
Ul=Il*R=(Np/Ns)*Ip*R* (1-el)
el =[(R01 + R)/Z1]/[1+(R01 + R)/Z1]
Ul: 负载电阻上的电压
第 1级电流互感器的测量误差为： el， 且为负值。
对于第 2级电流互感器， 有以下方程式：
Ip*Np - Il*Ns - I2*Nf - Iz2*Nf =0
Iz2 = E2 /Z2
E2 = I2*R02 + I2*Rf
其中： Nf: 辅助线圈的匝数；
12： 辅助线圈中的电流；
Iz2: 辅助磁芯的励磁电流；
E2: 辅助线圈上的感应电势； Z2: 辅助磁芯的励磁阻抗；
R02: 辅助线圈的阻抗；
Rf: 检测电阻；
将 I l=(Np/Ns)*Ip* (l_el)代入以上方程式并求解， 则可得到：
I2=(Np/Nf)*Ip*el* (l_e2)
e2 = [ (R02 + Rf) /Z2] / [ l + (R02 + Rf) /Z2]
第 2级电流互感器的测量误差为： e2， 且为负值。
由于检测电阻的阻值与负载电阻的阻值的比值等于辅助线圈的匝数与二次线圈的匝数的 比值， 故有：
Rf/R = Nf/Ns 说
辅助线圈的同名端和二次线圈的非同名端间的电压为：
U = I 1*R + I2*Rf 书
U =(Np/Ns)*Ip*R* (卜 el*e2)
U =(Np/Ns)*Ip*R* (卜 e)
e = el*e2
U: 辅助线圈的同名端和二次线圈的非同名端间的电压。
电流互感器的测量误差为： e， 且为负值。
电流互感器的测量误差 e为第 1级电流互感器的测量误差 el与第 2级电流互感器的测量 误差 e2的乘积， 因此， 电流互感器的测量误差 e与第 1级电流互感器的测量误差 el相比较 要小得多。
此外， 对于第 2级电流互感器， 有以下方程式：
Ip*Np - I l*Ns - I2*Nf - Iz2*Nf =0
将 I l=(Np/Ns)*Ip* (1-el)代入上述方程式
则有： （Ip*el) *Np - I2*Nf - Iz2*Nf =0
即等效使用第 2级电流互感器对电流 (Ip*el)进行检测，由于电流（Ip*el)比第 1级电流互 感器的输入一次线圈中的电流 Ip要小得多， 因此， 第 2级电流互感器的磁芯可以使用较小截 面积的磁芯， 即辅助磁芯的截面积可以小于主磁芯的截面积， 从而减少电流互感器的材料使 用量， 降低电流互感器的制造成本。
当使用以上的 2 级的电流互感器的测量精度仍不能满足对电流互感器测量精度的要求 时， 可以使用更多级的电流互感器以满足对电流互感器测量精度的要求。
技术方案二： 一种电流互感器， 包括主磁芯、 n个辅助磁芯、 一次线圈、 二次线圈、 n个 辅助线圈、 连接在二次线圈两端的负载电阻、 连接在第 1辅助线圈两端的第 1检测电阻、 连 接在第 2辅助线圈两端的第 2检测电阻、 直至连接在第 n辅助线圈两端的第 n检测电阻， n 为大于或等于 2的整数， 第 1检测电阻的阻值与负载电阻的阻值的比值等于第 1辅助线圈的 匝数与二次线圈的匝数的比值， 第 2检测电阻的阻值与负载电阻的阻值的比值等于第 2辅助 线圈的匝数与二次线圈的匝数的比值， 以此类推， 直至第 n检测电阻的阻值与负载电阻的阻 值的比值等于第 n辅助线圈的匝数与二次线圈的匝数的比值；
一次线圈和二次线圈绕制于主磁芯和第 1辅助磁芯至第 n辅助磁芯上， 第 1辅助线圈绕 制于第 1辅助磁芯至第 n辅助磁芯上，第 2辅助线圈绕制于第 2辅助磁芯至第 n辅助磁芯上， 以此类推， 直至第 n辅助线圈绕制于第 n辅助磁芯上；
二次线圈的同名端与第 1辅助线圈的非同名端相连接， 第 1辅助线圈的同名端与第 2辅 助线圈的非同名端相连接， 以此类推， 直至第 n-1辅助线圈的同名端与第 n辅助线圈的非同 名端相连接； 说
一次线圈的两端为电流输入端， 第 n辅助线圈的同名端以及二次线圈的非同名端为信号 输出端； 或者， 第 n辅助线圈的同名端以及二次线书圈的两端为信号输出端， 当需要电流互感 器的输出为三端输出信号时使用。
由主磁芯、 一次线圈、 二次线圈和负载电阻构成第 1级电流互感器。
由第 1辅助磁芯、 一次线圈、 二次线圈、 第 1辅助线圈和第 1检测电阻构成第 2级电流 互感器。
由第 2辅助磁芯、 一次线圈、 二次线圈、 第 1辅助线圈至第 2辅助线圈和第 2检测电阻 构成第 3级电流互感器。
以此类推， 直至：
由第 n辅助磁芯、 一次线圈、 二次线圈、 第 1辅助线圈至第 n辅助线圈和第 n检测电阻 构成第 n+1级电流互感器。
对于第 1级电流互感器， 有以下方程式：
Ip*Np - I l*Ns - Iz l*Ns =0
Iz l = El /Zl
El = I 1*R01 + I 1*R
其中： Np: —次线圈的匝数；
Ns: 二次线圈的匝数；
Ip: 一次线圈中的电流；
II： 二次线圈中的电流；
Iz l : 主磁芯的励磁电流；
E1 : 二次线圈上的感应电势；
Z1 : 主磁芯的励磁阻抗；
R01 : 二次线圈的阻抗； R: 负载电阻；
求解以上方程式， 则可得到：
Il=(Np/Ns)*Ip* (1-el)
Ul=Il*R=(Np/Ns)*Ip*R* (1-el)
el =[(R01 + R)/Z1]/[1+(R01 + R)/Z1]
Ul: 负载电阻上的电压
第 1级电流互感器的测量误差为： el， 且为负值。
对于第 2级电流互感器， 有以下方程式：
Ip*Np - Il*Ns - I2*Nf 1 - Iz2*Nfl =0
Iz2 = E2 /Z2 说
E2 = I2*R02 + I2*Rfl
其中： Nfl: 第 1辅助线圈的匝数； 书
12： 第 1辅助线圈中的电流；
Iz2: 第 1辅助磁芯的励磁电流；
E2: 第 1辅助线圈上的感应电势；
Z2: 第 1辅助磁芯的励磁阻抗；
R02: 第 1辅助线圈的阻抗；
Rfl: 第 1检测电阻；
将 Il=(Np/Ns)*Ip*(l_el)代入以上方程式并求解， 则可得到：
I2=(Np/Nfl)*Ip*el* (l_e2)
e2 =[(R02 + Rfl)/Z2]/[1 + (R02 + Rfl)/Z2]
第 2级电流互感器的测量误差为： e2， 且为负值。
以此类推， 直至：
对于第 n+1级电流互感器， 有以下方程式：
Ip*Np -Il*Ns -I2*Nfl - - I(n+l)*Nfn - Iz (n+1) *Nfn =0
Iz(n+1) = E(n+1) /Z(n+1)
E(n+1) = I(n+l)*R0(n+l) + I(n+l)*Rfn
Rfn/R = Nfn/Ns
其中： Nfn: 第 n辅助线圈的匝数；
I (n+1): 第 n辅助线圈中的电流；
Iz(n+1): 第 n辅助磁芯的励磁电流；
E(n+1): 第 n辅助线圈上的感应电势；
Z(n+1): 第 n辅助磁芯的励磁阻抗； R0 (n+1) : 第 n辅助线圈的阻抗；
Rfn: 第 n检测电阻；
对以上方程式并求解， 则可得到：
I (n+1) =(Np/Nfn)*Ip*el*e2*'"* [ 1-e (n+1) ]
e (n+l) = { [R0 (n+l) + Rfn] /Z (n+1) } / { 1 + [R0 (n+1) + Rfn) ] /Z (n+1) }
第 (n+1)级电流互感器的测量误差为： e (n+l)， 且为负值。
由于第 1检测电阻的阻值与负载电阻的阻值的比值等于第 1辅助线圈的匝数与二次线圈 的匝数的比值， 第 2检测电阻的阻值与负载电阻的阻值的比值等于第 2辅助线圈的匝数与二 次线圈的匝数的比值， 以此类推， 直至第 n检测电阻的阻值与负载电阻的阻值的比值等于第 n辅助线圈的匝数与二次线圈的匝数的比值说， 故有：
Rfl/R = Nfl/Ns
Rf2/R = Nf2/Ns 书
以此类推， 直至：
Rfn/R = Nfn/Ns
第 n辅助线圈的同名端和二次线圈的非同名端间的电压为：
U = I 1*R + I2*Rfl + + I (n+l) *Rfn
U =(Np/Ns)*Ip*R* [卜 el*e2* *e (n+1) ]
U =(Np/Ns)*Ip*R* (卜 e)
e = el*e2* *e (n+l)
U: 第 n辅助线圈的同名端和二次线圈的非同名端间的电压。
电流互感器的测量误差为： e， 且为负值。
电流互感器的测量误差 e为第 1级电流互感器的测量误差 el与第 2级电流互感器的测量 误差 e2直至与第 n+1级电流互感器的测量误差 e (n+1)的乘积， 因此， 电流互感器的测量误 差 e与第 1级电流互感器的测量误差 el相比较要小得多。
优选的， n等于 2时， 电流互感器包括主磁芯、 第 1辅助磁芯、 第 2辅助磁芯、 一次线 圈、 二次线圈、 第 1辅助线圈、 第 2辅助线圈、 连接在二次线圈两端的负载电阻、 连接在第 1辅助线圈两端的第 1检测电阻、 连接在第 2辅助线圈两端的第 2检测电阻， 第 1检测电阻 的阻值与负载电阻的阻值的比值等于第 1辅助线圈的匝数与二次线圈的匝数的比值， 第 2检 测电阻的阻值与负载电阻的阻值的比值等于第 2辅助线圈的匝数与二次线圈的匝数的比值； 一次线圈和二次线圈绕制于主磁芯和第 1辅助磁芯以及第 2辅助磁芯上， 第 1辅助线圈绕制 于第 1辅助磁芯和第 2辅助磁芯上， 第 2辅助线圈绕制于第 2辅助磁芯上； 二次线圈的同名 端与第 1辅助线圈的非同名端相连接， 第 1辅助线圈的同名端与第 2辅助线圈的非同名端相 连接； 一次线圈的两端为电流输入端， 第 2辅助线圈的同名端以及二次线圈的非同名端为信 号输出端； 或者， 第 2辅助线圈的同名端以及二次线圈的两端为信号输出端， 当需要电流互 感器的输出为三端输出信号时使用。
第 2辅助线圈的同名端和二次线圈的非同名端间的电压为：
U =(Np/Ns)*Ip*R* el*e2*e3)
U =(Np/Ns)*Ip*R* e)
e = el e2 e3
U: 第 2辅助线圈的同名端和二次线圈的非同名端间的电压。
电流互感器的测量误差为： e， 且为负值。
电流互感器的测量误差 e为第 1级电流互感器的测量误差 el与第 2级电流互感器的测量 误差 e2以及与第 3级电流互感器的测量误说差 e3的乘积， 因此， 电流互感器的测量误差 e与 第 1级电流互感器的测量误差 el相比较要小得多。
技术方案三： 一种电流互感器， 包括： 主磁芯书、 辅助磁芯、 一次线圈、 二次线圈、 辅助 线圈， 一次线圈和二次线圈绕制于主磁芯和辅助磁芯上， 辅助线圈绕制于辅助磁芯上； 一次线圈的两端为电流输入端， 辅助线圈的两端以及二次线圈的两端为信号输出端； 或 者， 辅助线圈的非同名端和二次线圈的同名端相连接； 辅助线圈的同名端以及二次线圈的两 端为信号输出端。
使用时， 若电流互感器的辅助线圈的非同名端和二次线圈的同名端未连接时则应在外部 电路中连接， 电流互感器的二次线圈的两端与外部电路中的负载电阻相连接， 电流互感器的 辅助线圈的两端与外部电路中的检测电阻相连接， 当选择的检测电阻的阻值与负载电阻的阻 值的比值等于辅助线圈的匝数与二次线圈的匝数的比值时， 辅助线圈的同名端和二次线圈的 非同名端间的电压为：
U =(Np/Ns)*Ip*R* el*e2)
U =(Np/Ns)*Ip*R* e)
e = el*e2
其巾：
U: 辅助线圈的同名端和二次线圈的非同名端间的电压。
Np: 一次线圈的匝数；
Ns: 二次线圈的匝数；
Ip: 一次线圈中的电流；
R: 负载电阻；
el : 第 1级电流互感器的测量误差
e2: 第 2级电流互感器的测量误差
电流互感器的测量误差为： e， 且为负值。 电流互感器的测量误差 e为第 1级电流互感器的测量误差 el与第 2级电流互感器的测量 误差 e2的乘积， 因此， 电流互感器的测量误差 e与第 1级电流互感器的测量误差 el相比较 要小得多。
辅助磁芯的截面积可以小于主磁芯的截面积， 从而减少电流互感器的材料使用量， 降低 电流互感器的制造成本。
技术方案四： 一种电流互感器， 包括主磁芯、 n个辅助磁芯、 一次线圈、 二次线圈、 n个 辅助线圈， n为大于或等于 2的整数， 一次线圈和二次线圈绕制于主磁芯和第 1辅助磁芯至 第 n辅助磁芯上， 第 1辅助线圈绕制于第 1辅助磁芯至第 n辅助磁芯上， 第 2辅助线圈绕制 于第 2辅助磁芯至第 n辅助磁芯上， 以此类推， 直至第 n辅助线圈绕制于第 n辅助磁芯上； 二次线圈的同名端与第 1辅助线圈的非同说名端相连接， 第 1辅助线圈的同名端与第 2辅助线 圈的非同名端相连接， 以此类推， 直至第 n-1辅助线圈的同名端与第 n辅助线圈的非同名端 相连接； 一次线圈的两端为电流输入端， n 个辅助书线圈的同名端以及二次线圈的两端为信号 输出端。
使用时， 电流互感器的二次线圈的两端与外部电路中的负载电阻相连接， 电流互感器的 二次线圈的同名端和第 1辅助线圈的同名端与外部电路中的第 1检测电阻相连接， 电流互感 器的第 1辅助线圈的同名端和第 2辅助线圈的同名端与外部电路中的第 2检测电阻相连接， 以此类推， 直至电流互感器的第 n-1辅助线圈的同名端和第 n辅助线圈的同名端与外部电路 中的第 n检测电阻相连接；
当第 1检测电阻的阻值与负载电阻的阻值的比值等于第 1辅助线圈的匝数与二次线圈的 匝数的比值， 第 2检测电阻的阻值与负载电阻的阻值的比值等于第 2辅助线圈的匝数与二次 线圈的匝数的比值， 以此类推， 直至第 n检测电阻的阻值与负载电阻的阻值的比值等于第 n 辅助线圈的匝数与二次线圈的匝数的比值时， 则第 n辅助线圈的同名端和二次线圈的非同名 端间的电压为：
U =(Np/Ns)*Ip*R* [卜 el*e2* *e (n+1) ]
U =(Np/Ns)*Ip*R* (卜 e)
e = el*e2* *e (n+l)
U: 第 n辅助线圈的同名端和二次线圈的非同名端间的电压。
电流互感器的测量误差为： e， 且为负值。
电流互感器的测量误差 e为第 1级电流互感器的测量误差 el与第 2级电流互感器的测量 误差 e2直至与第 n+1级电流互感器的测量误差 e (n+1)的乘积， 因此， 电流互感器的测量误 差 e与第 1级电流互感器的测量误差 el相比较要小得多。
优选的， n等于 2时， 电流互感器包括主磁芯、 第 1辅助磁芯、 第 2辅助磁芯、 一次线 圈、 二次线圈、 第 1辅助线圈、 第 2辅助线圈， 一次线圈和二次线圈绕制于主磁芯和第 1辅 助磁芯以及第 2辅助磁芯上， 第 1辅助线圈绕制于第 1辅助磁芯和第 2辅助磁芯上， 第 2辅 助线圈绕制于第 2辅助磁芯上； 第 1辅助线圈的非同名端与二次线圈的同名端相连接， 第 1 辅助线圈的同名端与第 2辅助线圈的非同名端相连接； 一次线圈的两端为电流输入端， 第 2 辅助线圈的同名端、 第 1辅助线圈的同名端以及二次线圈的两端为信号输出端。
使用时，电流互感器的二次线圈的两端与外部电路中的负载电阻相连接，电流互感器的二 次线圈的同名端和第 1辅助线圈的同名端与外部电路中的第 1检测电阻相连接， 电流互感器 的第 1辅助线圈的同名端和第 2辅助线圈的同名端与外部电路中的第 2检测电阻相连接； 当选择第 1检测电阻的阻值与负载电阻的阻值的比值等于第 1辅助线圈的匝数与二次线 圈的匝数的比值， 第 2检测电阻的阻值与负载电阻的阻值的比值等于第 2辅助线圈的匝数与 二次线圈的匝数的比值时， 则第 2辅助线说圈的同名端和二次线圈的非同名端间的电压为：
U =(Np/Ns)*Ip*R* el*e2*e3)
U =(Np/Ns)*Ip*R* e) 书
e = el e2 e3
U: 第 n辅助线圈的同名端和二次线圈的非同名端间的电压。
电流互感器的测量误差为： e， 且为负值。
电流互感器的测量误差 e为第 1级电流互感器的测量误差 el与第 2级电流互感器的测量 误差 e2直至与第 3级电流互感器的测量误差 e3的乘积， 因此， 电流互感器的测量误差 e与 第 1级电流互感器的测量误差 el相比较要小得多。
以上技术方案中使用磁芯叠绕结构， 此外， 还可以采用磁芯分离式结构， 即分别在磁芯 上绕制线圈， 再将绕制好线圈的磁芯放置在一起， 并将线圈按要求进行连接。
技术方案五： 一种电流互感器， 包括主磁芯、 辅助磁芯、 一次线圈第 1绕组、 一次线圈 第 2绕组、 二次线圈第 1绕组、 二次线圈第 2绕组、 辅助线圈、 连接在二次线圈第 1绕组的 非同名端和二次线圈第 2绕组的同名端的负载电阻、 连接在辅助线圈两端的检测电阻； 检测 电阻的阻值与负载电阻的阻值的比值等于辅助线圈的匝数与二次线圈第 2 绕组的匝数的比 值， 一次线圈第 1绕组的匝数与二次线圈第 1绕组的匝数的比值等于一次线圈第 2绕组的匝 数与二次线圈第 2绕组的匝数的比值； 一次线圈第 1绕组和二次线圈第 1绕组绕制于主磁芯 上， 一次线圈第 2组和二次线圈第 2绕组以及辅助线圈绕制于辅助磁芯上；
一次线圈第 1绕组的同名端与一次线圈第 2绕组的非同名端相连接， 二次线圈第 1绕组 的同名端与二次线圈第 2绕组的非同名端相连接， 二次线圈第 2绕组的同名端与辅助线圈的 非同名端相连接；
一次线圈第 1绕组的非同名端和一次线圈第 2绕组的同名端为电流输入端， 辅助线圈的 同名端和二次线圈第 1绕组的非同名端为信号输出端； 或者， 辅助线圈的同名端、 二次线圈 第 2绕组的同名端以及二次线圈第 1绕组的非同名端为信号输出端， 当需要电流互感器的输 出为三端输出信号时使用。
由主磁芯、 一次线圈第 1绕组、 二次线圈第 1绕组、 二次线圈第 2绕组和负载电阻构成 第 1级电流互感器。
由辅助磁芯、 一次线圈第 2绕组、 二次线圈第 2绕组、 辅助线圈和检测电阻构成第 2级 电流互感器。
对于第 1级电流互感器和第 2级电流互感器， 有以下方程式：
Ip*Npl - Il*Nsl - Izl*Nsl =0
Ip*Np2 - Il*Ns2 - I2*Nf - Iz2*Nf =0
Npl/Nsl = Np2/Ns2
Izl = El/Zl 说
E1+E2 = I1*R01 + I1*R
Iz2 = E2 /Z2 书
E2 = I2*R02 + I2*Rf
Rf/ R = Nf/Ns2
其巾：
Npl: 一次线圈第 1绕组的匝数；
Nsl: 二次线圈第 1绕组的匝数；
Np2: 一次线圈第 2绕组的匝数；
Ns2: 二次线圈第 2绕组的匝数；
Nf: 辅助线圈的匝数；
Ip: 一次线圈第 1绕组及一次线圈第 2绕组中的电流；
II： 二次线圈第 1绕组及二次线圈第 2绕组中的电流；
12： 辅助线圈中的电流；
Izl: 主磁芯的励磁电流；
Iz2: 辅助磁芯的励磁电流；
E1: 二次线圈第 1绕组上的感应电势；
E2: 二次线圈第 2绕组上的感应电势；
Z1: 主磁芯的励磁阻抗；
Z2: 辅助磁芯的励磁阻抗；
R01: 二次线圈第 1绕组以及二次线圈第 2绕组的总的线圈阻抗；
R02: 辅助线圈的阻抗；
R: 负载电阻；
Rf: 检测电阻； 求解以上方程式， 则可得到：
I l=(Npl/Nsl)*Ip* (1-el)
I2=(Np2/Nf)*Ip*el* (l-e2)
el = [ (R01 + R) /Z1] / [ 1+ (R01 + R) /Z1 +k]
e2 = [ (R02 + Rf) /Z2] / [ l + (R02 + Rf) /Z2]
k= (Ns2/Nf) * (Z2/Zl) *e2
辅助线圈的同名端和二次线圈第 1绕组的非同名端间的电压为：
U = I 1*R + I2*Rf
U =(Npl/Nsl)*Ip*R* (卜 el*e2)
U =(Npl/Nsl)*Ip*R*(l— e) 说
e = el*e2
U: 辅助线圈的同名端和二次线圈的非同名端书间的电压。
电流互感器的测量误差为： e， 且为负值。
电流互感器的测量误差 e为第 1级电流互感器的测量误差 el与第 2级电流互感器的测量 误差 e2的乘积， 因此， 电流互感器的测量误差 e与第 1级电流互感器的测量误差 el相比较 要小得多。
此外， 对于第 2级电流互感器， 有以下方程式：
Ip*Np2 - I l*Ns2 - I2*Nf - Iz2*Nf =0
由于： I l=(Npl/Nsl)*Ip* (1-el) =(Np2/Ns2)*Ip* (l_el)
因此有： （Ip*el) *Np2 - I2*Nf - Iz2*Nf =0
即第 2级电流互感器用于对电流（Ip*el)的检测， 由于电流（Ip*el)比第 1级电流互感器 的输入一次线圈中的电流 Ip要小得多， 因此， 第 2级电流互感器的磁芯可以使用较小截面积 的磁芯， 即辅助磁芯的截面积可以小于主磁芯的截面积， 从而减少电流互感器的材料使用量， 降低电流互感器的制造成本。
技术方案六： 一种电流互感器， 包括主磁芯、 n个辅助磁芯、 一次线圈第 1绕组、 一次 线圈第 2绕组、 二次线圈第 1绕组、 二次线圈第 2绕组、 n个辅助线圈、 连接在二次线圈第 1 绕组的非同名端和二次线圈第 2绕组的同名端的负载电阻、 连接在第 1辅助线圈两端的第 1 检测电阻、 连接在第 2辅助线圈两端的第 2检测电阻、 直至连接在第 n辅助线圈两端的第 n 检测电阻， n为大于或等于 2的整数；
第 1检测电阻的阻值与负载电阻的阻值的比值等于第 1辅助线圈的匝数与二次线圈第 2 绕组的匝数的比值， 第 2检测电阻的阻值与负载电阻的阻值的比值等于第 2辅助线圈的匝数 与二次线圈第 2绕组的匝数的比值， 以此类推， 直至第 n检测电阻的阻值与负载电阻的阻值 的比值等于第 n辅助线圈的匝数与二次线圈第 2绕组的匝数的比值， 一次线圈第 1绕组的匝 数与二次线圈第 1绕组的匝数的比值等于一次线圈第 2绕组的匝数与二次线圈第 2绕组的匝 数的比值；
一次线圈第 1绕组和二次线圈第 1绕组绕制于主磁芯上， 一次线圈第 2组和二次线圈第 2绕组绕制于第 1辅助磁芯至第 n辅助磁芯上， 第 1辅助线圈绕制于第 1辅助磁芯至第 n辅 助磁芯上， 第 2辅助线圈绕制于第 2辅助磁芯至第 n辅助磁芯上， 以此类推， 直至第 n辅助 线圈绕制于第 n辅助磁芯上；
一次线圈第 1绕组的同名端与一次线圈第 2绕组的非同名端相连接， 二次线圈第 1绕组 的同名端与二次线圈第 2绕组的非同名端相连接， 二次线圈第 2绕组的同名端与第 1辅助线 圈的非同名端相连接， 第 1辅助线圈的同名端与第 2辅助线圈的非同名端相连接， 以此类推， 直至第 n-1的同名端与第 n辅助线圈的非说同名端相连接；
一次线圈第 1绕组的非同名端和一次线圈第 2绕组的同名端为电流输入端， 第 n辅助线 圈的同名端和二次线圈第 1绕组的非同名端为信号书输出端； 或者， 第 n辅助线圈的同名端、 二次线圈第 1绕组的非同名端、 二次线圈第 2绕组的同名端为信号输出端， 当需要电流互感 器的输出为三端输出信号时使用。
由主磁芯、 一次线圈第 1绕组、 二次线圈第 1绕组、 二次线圈第 2绕组和负载电阻构成 第 1级电流互感器。
由第 1辅助磁芯、 一次线圈第 2绕组、 二次线圈第 2绕组、 第 1辅助线圈和第 1检测电 阻构成第 2级电流互感器。
由第 2辅助磁芯、 一次线圈第 2绕组、 二次线圈第 2绕组、 第 1辅助线圈、 第 2辅助线 圈和第 2检测电阻构成第 3级电流互感器。
以此类推， 直至：
由第 n辅助磁芯、 一次线圈第 2绕组、 二次线圈第 2绕组、 第 1辅助线圈直至第 n辅助 线圈和第 n检测电阻构成第 n+1级电流互感器。
对于第 1级电流互感器和第 2级电流互感器， 有以下方程式：
Ip*Npl - I l*Ns l - Iz l*Ns l =0
Ip*Np2 - I l*Ns2 - I2*Nf 1 - Iz2*Nfl =0
Npl/Ns l = Np2/Ns2
Iz l = El/Zl
E1+E2 = I 1*R01 + I 1*R
Iz2 = E2 /Z2
E2 = I2*R02 + I2*Rfl
Rfl/ R = Nfl/Ns2
其巾： Npl: 一次线圈第 1绕组的匝数；
Nsl: 二次线圈第 1绕组的匝数；
Np2: 一次线圈第 2绕组的匝数；
Ns2: 二次线圈第 2绕组的匝数；
Nfl: 第 1辅助线圈的匝数；
Ip: 一次线圈第 1绕组以及一次线圈第 2绕组中的电流；
II： 二次线圈第 1绕组以及二次线圈第 2绕组中的电流；
12： 第 1辅助线圈中的电流；
Izl: 主磁芯的励磁电流；
Iz2: 第 1辅助磁芯的励磁电流； 说
E1: 二次线圈第 1绕组上的感应电势；
E2: 二次线圈第 2绕组上的感应电势； 书
Z1: 主磁芯的励磁阻抗；
Z2: 第 1辅助磁芯的励磁阻抗；
R01: 二次线圈第 1绕组及二次线圈第 2绕组的总的线圈阻抗;
R02: 第 1辅助磁芯的线圈阻抗；
R: 负载电阻；
Rfl: 第 1检测电阻；
求解以上方程式， 则可得到：
Il=(Npl/Nsl)*Ip* (1-el)
I2=(Np2/Nfl)*Ip*el* (l-e2)
el =[(R01 + R)/Z1]/[1+(R01 + R)/Z1 +k]
e2 =[(R02 + Rfl)/Z2]/[1 + (R02 + Rfl)/Z2]
k= (Ns2/Nfl)*(Z2/Zl)*e2 以此类推， 直至：
对于第 n+1级电流互感器， 有以下方程式：
Ip*Np-Il*Ns-I2*Nfl - - I(n+l)*Nfn - Iz(n+l)*Nfn =0
Iz(n+1) = E(n+1) /Z(n+1)
E(n+1) = I(n+l)*R0(n+l) + I(n+l)*Rfn
Rfn/R = Nfn/Ns
其巾：
Nfn: 第 n辅助线圈的匝数； Kn+l): 第 n辅助线圈中的电流；
Iz(n+1): 第 n辅助磁芯的励磁电流；
E(n+1): 第 n辅助线圈上的感应电势；
Z(n+1): 第 n辅助磁芯的励磁阻抗；
R0(n+1): 第 n辅助磁芯的线圈阻抗；
Rfn: 第 n检测电阻；
求解以上方程式， 则可得到：
I (n+1) =(Np/Nfn)*Ip*el*e2* * [l_e (n+1) ]
e(n+l) ={[R0(n+l) + Rfn] /Z (n+1) } / {1 + [R0(n+1) + Rfn) ] /Z (n+1) }
第 (n+1)级电流互感器的测量误差为：说 e(n+l)， 且为负值。
由于第 1检测电阻的阻值与负载电阻的阻值的比值等于第 1辅助线圈的匝数与二次线圈 的匝数的比值， 第 2检测电阻的阻值与负载电阻的书阻值的比值等于第 2辅助线圈的匝数与二 次线圈的匝数的比值， 以此类推， 直至第 n检测电阻的阻值与负载电阻的阻值的比值等于第 n辅助线圈的匝数与二次线圈的匝数的比值， 故有：
Rfl/R = Nfl/Ns
Rf2/R = Nf2/Ns
以此类推， 直至：
Rfn/R = Nfn/Ns
第 n辅助线圈的同名端和二次线圈的非同名端间的电压为：
U=I1*R + I2*Rfl + + I(n+l)*Rfn
U =(Np/Ns)*Ip*R* [卜 el*e2* *e (n+1) ]
U =(Np/Ns)*Ip*R* (卜 e)
e = el*e2* *e(n+l)
U: 第 n辅助线圈的同名端和二次线圈的非同名端间的电压。
电流互感器的测量误差为： e， 且为负值。
电流互感器的测量误差 e为第 1级电流互感器的测量误差 el与第 2级电流互感器的测量 误差 e2直至与第 n+1级电流互感器的测量误差 e (n+1)的乘积， 因此， 电流互感器的测量误 差 e与第 1级电流互感器的测量误差 el相比较要小得多。
优选的， 当 n等于 2时， 电流互感器包括主磁芯、 第 1辅助磁芯、 第 2辅助磁芯、 一次 线圈第 1绕组、 一次线圈第 2绕组、 二次线圈第 1绕组、 二次线圈第 2绕组、 第 1辅助线圈、 第 2辅助线圈、 连接在二次线圈第 1绕组的非同名端和二次线圈第 2绕组的同名端的负载电 阻、 连接在第 1辅助线圈两端的第 1检测电阻、 连接在第 2辅助线圈两端的第 2检测电阻； 第 1检测电阻的阻值与负载电阻的阻值的比值等于第 1辅助线圈的匝数与二次线圈第 2绕组 的匝数的比值， 第 2检测电阻的阻值与负载电阻的阻值的比值等于第 2辅助线圈的匝数与二 次线圈第 2绕组的匝数的比值， 一次线圈第 1绕组的匝数与二次线圈第 1绕组的匝数的比值 等于一次线圈第 2绕组的匝数与二次线圈第 2绕组的匝数的比值；
一次线圈第 1绕组和二次线圈第 1绕组绕制于主磁芯上， 一次线圈第 2组和二次线圈第 2绕组绕制于第 1辅助磁芯和第 2辅助磁芯上， 第 1辅助线圈绕制于第 1辅助磁芯和第 2辅 助磁芯上， 第 2辅助线圈绕制于第 2辅助磁芯上；
一次线圈第 1绕组的同名端与一次线圈第 2绕组的非同名端相连接， 二次线圈第 1绕组 的同名端与二次线圈第 2绕组的非同名端相连接， 二次线圈第 2绕组的同名端与第 1辅助线 圈的非同名端相连接， 第 1辅助线圈的同名端与第 2辅助线圈的非同名端相连接；
一次线圈第 1绕组的非同名端和一次说线圈第 2绕组的同名端为电流输入端， 第 2辅助线 圈的同名端和二次线圈第 1绕组的非同名端为信号输出端； 或者， 第 2辅助线圈的同名端、 二次线圈第 1绕组的非同名端、 二次线圈第 2绕组书的同名端为信号输出端， 当需要电流互感 器的输出为三端输出信号时使用。
第 2辅助线圈的同名端和二次线圈第 1绕组的非同名端间的电压为：
U =(Np/Ns)*Ip*R* el*e2*e3)
U =(Np/Ns)*Ip*R* e)
e = el e2 e3
U: 第 2辅助线圈的同名端和二次线圈的非同名端间的电压。
电流互感器的测量误差为： e， 且为负值。
电流互感器的测量误差 e为第 1级电流互感器的测量误差 el与第 2级电流互感器的测量 误差 e2及与第 3级电流互感器的测量误差 e3的乘积， 因此， 电流互感器的测量误差 e与第 1级电流互感器的测量误差 el相比较要小得多。
技术方案七： 一种电流互感器， 包括主磁芯、 辅助磁芯、 一次线圈第 1绕组、 一次线圈 第 2绕组、 二次线圈第 1绕组、 二次线圈第 2绕组、 辅助线圈， 一次线圈第 1绕组和二次线 圈第 1绕组绕制于主磁芯上， 一次线圈第 2绕组和二次线圈第 2绕组和二次线圈第 2绕组以 及辅助线圈绕制于辅助磁芯上；
一次线圈第 1绕组的同名端与一次线圈第 2绕组的非同名端相连接， 二次线圈第 1绕组 的同名端与二次线圈第 2绕组的非同名端相连接；
一次线圈第 1绕组的匝数与二次线圈第 1绕组的匝数的比值等于一次线圈第 2绕组的匝 数与二次线圈第 2绕组的匝数的比值；
一次线圈第 1绕组的非同名端和一次线圈第 2绕组的同名端为电流输入端， 辅助线圈的 两端和二次线圈第 2绕组的同名端以及二次线圈第 1绕组的非同名端作为信号输出端；或者， 二次线圈第 2绕组的同名端与辅助线圈的非同名端相连接， 辅助线圈的两端以及二次线圈第 1绕组的非同名端作为信号输出端。
使用时， 若二次线圈第 2绕组的同名端与辅助线圈的非同名端未连接， 则应在外部电路 中进行连接， 二次线圈第 1绕组的非同名端与二次线圈第 2绕组的同名端与外部电路中的负 载电阻相连接， 辅助线圈两端与外部电路中的检测电阻相连接， 当检测电阻的阻值与负载电 阻的阻值的比值等于辅助线圈的匝数与二次线圈第 2绕组的匝数的比值时， 辅助线圈的同名 端和二次线圈第 1绕组的非同名端间的电压为：
U =(Npl/Nsl)*Ip*R* (卜 el*e2)
U =(Npl/Nsl)*Ip*R*(l— e)
e = el*e2
Npl : 一次线圈第 1绕组的匝数； 说
Nsl : 二次线圈第 1绕组的匝数；
Ip: 一次线圈第 1绕组及一次线圈第 2绕组中书的电流；
R: 负载电阻；
el : 第 1级电流互感器的测量误差
e2: 第 2级电流互感器的测量误差
U: 辅助线圈的同名端和二次线圈的非同名端间的电压。
电流互感器的测量误差为： e， 且为负值。
电流互感器的测量误差 e为第 1级电流互感器的测量误差 el与第 2级电流互感器的测量 误差 e2的乘积， 因此， 电流互感器的测量误差 e与第 1级电流互感器的测量误差 el相比较 要小得多。
辅助磁芯的截面积可以小于主磁芯的截面积， 从而减少电流互感器的材料使用量， 降低 电流互感器的制造成本。
技术方案八： 一种电流互感器， 包括主磁芯、 n个辅助磁芯、 一次线圈第 1绕组、 一次 线圈第 2绕组、 二次线圈第 1绕组、 二次线圈第 2绕组、 n个辅助线圈， n为大于或等于 2的 整数； 一次线圈第 1绕组的匝数与二次线圈第 1绕组的匝数的比值等于一次线圈第 2绕组的 匝数与二次线圈第 2绕组的匝数的比值；
一次线圈第 1绕组和二次线圈第 1绕组绕制于主磁芯上， 一次线圈第 2绕组和二次线圈 第 2绕组以及第 1辅助线圈绕制于第 1辅助磁芯至第 n辅助磁芯上， 第 2辅助线圈绕制于第 2辅助磁芯至第 n辅助磁芯上， 以此类推， 直至第 n辅助线圈绕制于第 n辅助磁芯上；
一次线圈第 1绕组的同名端与一次线圈第 2绕组的非同名端相连接， 二次线圈第 1绕组 的同名端与二次线圈第 2绕组的非同名端相连接， 二次线圈第 2绕组的同名端与第 1辅助线 圈的非同名端相连接， 第 1辅助线圈的同名端与第 2辅助线圈的非同名端相连接， 以此类推， 直至第 n-1的辅助线圈同名端与第 n辅助线圈的非同名端相连接； 一次线圈第 1绕组的非同名端和一次线圈第 2绕组的同名端为电流输入端，第 1辅助线圈 的同名端、 第 2辅助线圈的同名端、 直至第 n辅助线圈的同名端、 二次线圈第 2绕组的同名 端、 二次线圈第 1绕组的非同名端为信号输出端。
使用时， 二次线圈第 1绕组的非同名端与辅助线圈的非同名端外部电路中的负载电阻相 连接， 第 1辅助线圈两端与外部电路中的第 1检测电阻相连接， 第 2辅助线圈两端与外部电 路中的第 2检测电阻相连接， 以此类推， 直至第 n辅助线圈两端与外部电路中的第 n检测电 阻相连接；
当第 1检测电阻的阻值与负载电阻的阻值的比值等于第 1辅助线圈的匝数与二次线圈的 匝数的比值， 第 2检测电阻的阻值与负载电阻的阻值的比值等于第 2辅助线圈的匝数与二次 线圈的匝数的比值， 以此类推， 直至第 n说检测电阻的阻值与负载电阻的阻值的比值等于第 n 辅助线圈的匝数与二次线圈的匝数的比值时；
第 n辅助线圈的同名端和二次线圈第 1绕组的书非同名端间的电压为：
U =(Npl/Nsl)*Ip*R* [卜 el*e2* *e (n+1) ]
U =(Np/Ns)*Ip*R* (卜 e)
e = el*e2* *e (n+l)
U: 第 n辅助线圈的同名端和二次线圈第 1绕组的非同名端间的电压
电流互感器的测量误差为： e， 且为负值。
电流互感器的测量误差 e为第 1级电流互感器的测量误差 el与第 2级电流互感器的测量 误差 e2直至与第 n+1级电流互感器的测量误差 e (n+1)的乘积， 因此， 电流互感器的测量误 差 e与第 1级电流互感器的测量误差 el相比较要小得多。
优选的， 当 n等于 2时， 电流互感器包括主磁芯、 第 1辅助磁芯、 第 2辅助磁芯、 一次 线圈第 1绕组、 一次线圈第 2绕组、 二次线圈第 1绕组、 二次线圈第 2绕组、 第 1辅助线圈、 第 2辅助线圈； 一次线圈第 1绕组的匝数与二次线圈第 1绕组的匝数的比值等于一次线圈第 2绕组的匝数与二次线圈第 2绕组的匝数的比值；
一次线圈第 1绕组和二次线圈第 1绕组绕制于主磁芯上， 一次线圈第 2绕组、 二次线圈 第 2绕组以及第 1辅助线圈绕制于第 1辅助磁芯和第 2辅助磁芯上， 第 2辅助线圈绕制于第 2辅助磁芯上；
一次线圈第 1绕组的同名端与一次线圈第 2绕组的非同名端相连接， 二次线圈第 1绕组 的同名端与二次线圈第 2绕组的非同名端相连接， 二次线圈第 2绕组的同名端与第 1辅助线 圈的非同名端相连接， 第 1辅助线圈的同名端与第 2辅助线圈的非同名端相连接；
一次线圈第 1绕组的非同名端和一次线圈第 2绕组的同名端为电流输入端， 第 1辅助线 圈的同名端、 第 2辅助线圈的同名端、 二次线圈第 2绕组的同名端、 二次线圈第 1绕组的非 同名端为信号输出端。 使用时， 二次线圈第 1绕组的非同名端和二次线圈第 2绕组的同名端与外部电路中的负 载电阻相连接， 二次线圈第 2绕组的同名端和第 1辅助线圈的同名端与外部电路中的第 1检 测电阻相连接， 第 1辅助线圈的同名端和第 2辅助线圈的同名端与外部电路中的第 2检测电 阻相连接；
当第 1检测电阻的阻值与负载电阻的阻值的比值等于第 1辅助线圈的匝数与二次线圈第 2绕组的匝数的比值， 第 2检测电阻的阻值与负载电阻的阻值的比值等于第 2辅助线圈的匝 数与二次线圈第 2绕组的匝数的比值时；
第 2辅助线圈的同名端和二次线圈第 1绕组的非同名端间的电压为：
U =(Npl/Nsl)*Ip*R* el*e2*e3)
U =(Npl/Nsl)*Ip*R*(l— e) 说
e = el e2 e3
U: 第 2辅助线圈的同名端和二次线圈第 1绕书组的非同名端间的电压
电流互感器的测量误差为： e， 且为负值。
电流互感器的测量误差 e为第 1级电流互感器的测量误差 el与第 2级电流互感器的测量 误差 e2以及与第 3级电流互感器的测量误差 e3的乘积， 因此， 电流互感器的测量误差 e与 第 1级电流互感器的测量误差 el相比较要小得多。
在上述所有技术方案中， 可以进一步优选为： 辅助磁芯的截面积小于主磁芯的截面积， 从而减少电流互感器的材料使用量， 降低电流互感器的制造成本。
本发明的电流互感器具有测量精度高的特点。 附图说明
图 1是常规电流互感器的原理图。
图 2是本发明实施例 1的原理图。
图 3是本发明实施例 2的原理图。
图 4是本发明实施例 3的原理图。
图 5是本发明实施例 4的原理图。
图 6是本发明实施例 5的原理图。
图 7是本发明实施例 6的原理图。
图 8是本发明实施例 7的原理图。
图 9是本发明实施例 8的原理图。
图 10是本发明实施例 9的原理图。
图 11是本发明实施例 10的原理图。
图 12是本发明实施例 11的原理图。 图 13是本发明实施例 12的原理图。
图 14是本发明实施例 13的原理图。
图 15是本发明实施例 14的原理图。
图 16是本发明实施例 15的原理图。
图 17是本发明实施例 16的原理图。
图 18是本发明实施例 17的原理图。
图 19是本发明实施例 18的原理图。
图 20是本发明实施例 19的原理图。
图 21是本发明实施例 20的原理图。
注： 各图中， 线圈标有 的端为同名端说， 另一端为非同名端。 具体实施方式 书
下面结合实施例对本发明作进一步说明。
实施例 1 : 如图 2所示， 本实施例电流互感器包括： 主磁芯 1、 辅助磁芯 2、 一次线圈 3、 二次线圈 4、 辅助线圈 5、 连接在二次线圈 4两端的负载电阻 6、 连接在辅助线圈 5两端的检 测电阻 7， 检测电阻的阻值等于负载电阻的阻值， 辅助线圈的匝数等于二次线圈的匝数， 一 次线圈和二次线圈绕制于主磁芯和辅助磁芯上， 辅助线圈绕制于辅助磁芯上， 辅助线圈的非 同名端与二次线圈的同名端相连接， 一次线圈的两端为电流输入端， 辅助线圈的同名端以及 二次线圈的非同名端为信号输出端。
辅助线圈的同名端和二次线圈的非同名端间的电压为：
U =(Np/Ns)*Ip*R* (卜 el*e2)
电流互感器的测量误差为第 1级电流互感器的测量误差 el与第 2级电流互感器的测量误 差 e2的乘积。
辅助磁芯的截面积小于主磁芯的截面积。
实施例 2: 如图 3所示， 本实施例在实施例 1的基础上， 增设二次线圈的同名端为信号 输出端， 即辅助线圈的同名端、 二次线圈的同名端以及二次线圈的非同名端为信号输出端， 当需要电流互感器的输出为三端输出信号时使用。
实施例 3: 如图 4所示， 本实施例电流互感器包括： 主磁芯 1、 第 1辅助磁芯 2、 第 2辅 助磁芯 8、 一次线圈 3、 二次线圈 4、 第 1辅助线圈 5、 第 2辅助线圈 9、 连接在二次线圈 4 两端的负载电阻 6、连接在第 1辅助线圈 5两端的第 1检测电阻 7、连接在第 2辅助线圈 9两 端的第 2检测电阻 10， 第 1检测电阻的阻值等于负载电阻的阻值， 第 2检测电阻的阻值等于 负载电阻的阻值， 第 1辅助线圈的匝数等于二次线圈的匝数， 第 2辅助线圈的匝数等于二次 线圈的匝数， 一次线圈和二次线圈绕制于主磁芯、 第 1辅助磁芯以及第 2辅助磁芯上， 第 1 辅助线圈绕制于第 1辅助磁芯和第 2辅助磁芯上， 第 2辅助线圈绕制于第 2辅助磁芯上， 第 1辅助线圈的非同名端与二次线圈的同名端相连接， 第 1辅助线圈的同名端与第 2辅助线圈 的非同名端相连接， 一次线圈的两端为电流输入端， 第 2辅助线圈的同名端以及二次线圈的 非同名端为信号输出端。
第 2辅助线圈的同名端和二次线圈的非同名端间的电压为：
U =(Np/Ns)*Ip*R* (卜 el*e2*e3)
电流互感器的测量误差为第 1级电流互感器的测量误差 el与第 2级电流互感器的测量误 差 e2以及与第 3级电流互感器的测量误差 e3的乘积。
实施例 4: 如图 5所示， 本实施例在实施例 3的基础上， 增设二次线圈的同名端为信号 输出端， 即第 2辅助线圈的同名端、 二次说线圈的同名端以及二次线圈的非同名端为信号输出 端， 当需要电流互感器的输出为三端输出信号时使用。
实施例 5: 如图 6所示， 本实施例电流互感器书包括： 主磁芯 1、 第 1辅助磁芯 2、 第 2辅 助磁芯 8、 直至第 n辅助磁芯 11、 一次线圈 3、 二次线圈 4、 第 1辅助线圈 5、 第 2辅助线圈 9、 直至第 n辅助线圈 12、 连接在二次线圈 4两端的负载电阻 6、连接在第 1辅助线圈 5两端 的第 1检测电阻 7、 连接在第 2辅助线圈 9两端的第 2检测电阻 10、 直至连接在第 n辅助线 圈 12两端的第 n检测电阻 13， n为大于或等于 2的整数， 第 1检测电阻的阻值等于负载电阻 的阻值， 第 2检测电阻的阻值等于负载电阻的阻值， 以此类推， 直至第 n检测电阻的阻值等 于负载电阻的阻值， 第 1辅助线圈的匝数等于二次线圈的匝数， 第 2辅助线圈的匝数等于二 次线圈的匝数， 以此类推， 直至第 n辅助线圈的匝数等于二次线圈的匝数； 一次线圈和二次 线圈绕制于主磁芯和第 1辅助磁芯至第 n辅助磁芯上， 第 1辅助线圈绕制于第 1辅助磁芯至 第 n辅助磁芯上， 第 2辅助线圈绕制于第 2辅助磁芯至第 n辅助磁芯上， 以此类推， 直至第 n辅助线圈绕制于第 n辅助磁芯上； 二次线圈的同名端与第 1辅助线圈的非同名端相连接， 第 1辅助线圈的同名端与第 2辅助线圈的非同名端相连接， 以此类推， 直至第 n-1辅助线圈 的同名端与第 n辅助线圈的非同名端相连接， 一次线圈的两端为电流输入端， 第 n辅助线圈 的同名端以及二次线圈的非同名端为信号输出端。
第 n辅助线圈的同名端以及二次线圈的非同名端间的电压为：
U =(Np/Ns)*Ip*R* [卜 el*e2* *e (n+1) ]
电流互感器的测量误差为第 1级电流互感器的测量误差 el与第 2级电流互感器的测量误 差 e2直至与第 (n+1)级电流互感器的测量误差 e (n+1)的乘积。
实施例 6: 如图 7所示， 本实施例在实施例 5的基础上， 增设二次线圈的同名端为信号 输出端， 即第 n辅助线圈的同名端、 二次线圈的同名端以及二次线圈的非同名端为信号输出 端， 当需要电流互感器的输出为三端输出信号时使用。
实施例 7: 如图 8所示， 本实施例电流互感器包括： 主磁芯 1、 辅助磁芯 2、 一次线圈 3、 二次线圈 4、 辅助线圈 5， 辅助线圈的匝数等于二次线圈的匝数， 一次线圈和二次线圈绕制于 主磁芯和辅助磁芯上， 辅助线圈绕制于辅助磁芯上， 二次线圈的同名端与辅助线圈的非同名 端相连接， 一次线圈的两端为电流输入端， 辅助线圈的同名端以及二次线圈的两端为信号输 出端。
实施例 8: 如图 9所示， 本实施例电流互感器包括： 主磁芯 1、 辅助磁芯 2、 一次线圈 3、 二次线圈 4、 辅助线圈 5， 辅助线圈的匝数等于二次线圈的匝数， 一次线圈和二次线圈绕制于 主磁芯和辅助磁芯上， 辅助线圈绕制于辅助磁芯上， 一次线圈的两端为电流输入端， 辅助线 圈的两端以及二次线圈的两端为信号输出端。
实施例 9: 如图 10所示， 本实施例电流互感器包括： 主磁芯 1、 第 1辅助磁芯 2、 第 2 辅助磁芯 8、 一次线圈 3、 二次线圈 4、 第说 1辅助线圈 5、 第 2辅助线圈 9， 第 1辅助线圈的 匝数等于二次线圈的匝数， 第 2辅助线圈的匝数等于二次线圈的匝数， 一次线圈和二次线圈 绕制于主磁芯和第 1辅助磁芯以及第 2辅助磁芯上书， 第 1辅助线圈绕制于第 1辅助磁芯和第 2辅助磁芯上， 第 2辅助线圈绕制于第 2辅助磁芯上， 第 1辅助线圈的非同名端与二次线圈 的同名端相连接， 第 1辅助线圈的同名端与第 2辅助线圈的非同名端相连接， 一次线圈的两 端为电流输入端， 第 2辅助线圈的同名端、 第 1辅助线圈的同名端以及二次线圈的两端为信 号输出端。
实施例 10: 如图 11所示， 本实施例包括： 主磁芯 1、 第 1辅助磁芯 2、 第 2辅助磁芯 8、 直至第 n辅助磁芯 11、 一次线圈 3、 二次线圈 4、 第 1辅助线圈 5、 第 2辅助线圈 9、 直至第 n辅助线圈 12， n为大于或等于 2的整数， 第 1辅助线圈的匝数等于二次线圈的匝数， 第 2 辅助线圈的匝数等于二次线圈的匝数， 直至第 n辅助线圈的匝数等于二次线圈的匝数， 一次 线圈和二次线圈绕制于主磁芯和第 1辅助磁芯至第 n辅助磁芯上， 第 1辅助线圈绕制于第 1 辅助磁芯至第 n辅助磁芯上， 第 2辅助线圈绕制于第 2辅助磁芯至第 n辅助磁芯上， 以此类 推， 直至第 n辅助线圈绕制于第 n辅助磁芯上， 二次线圈的同名端与第 1辅助线圈的非同名 端相连接， 第 1辅助线圈的同名端与第 2辅助线圈的非同名端相连接， 以此类推， 直至第 n-1 辅助线圈的同名端与第 n辅助线圈的非同名端相连接， 一次线圈的两端为电流输入端， 第 1 辅助线圈的同名端、 第 2辅助线圈的同名端、 直至第 n辅助线圈的同名端以及二次线圈的两 端为信号输出端。
实施例 11 : 如图 12所示， 本实施例电流互感器包括： 主磁芯 1、 辅助磁芯 2、 一次线圈 第 1绕组 31、 一次线圈第 2绕组 32、 二次线圈第 1绕组 41、 二次线圈第 2绕组 42、 辅助线 圈 5、连接在二次线圈第 1绕组 41的非同名端和二次线圈第 2绕组 42的同名端的负载电阻 6、 连接在辅助线圈 5两端的检测电阻 7， 检测电阻的阻值等于负载电阻的阻值， 一次线圈第 1 绕组的匝数等于一次线圈第 2绕组的匝数， 二次线圈第 1绕组的匝数等于二次线圈第 2绕组 的匝数， 辅助线圈的匝数等于二次线圈第 2绕组的匝数， 一次线圈第 1绕组和二次线圈第 1 绕组绕制于主磁芯上， 一次线圈第 2绕组、 二次线圈第 2绕组以及辅助线圈绕制于辅助磁芯 上， 一次线圈第 1绕组的同名端与一次线圈第 2绕组的非同名端相连接， 二次线圈第 1绕组 的同名端与二次线圈第 2绕组的非同名端相连接， 二次线圈第 2绕组的同名端与辅助线圈的 非同名端相连接，一次线圈第 1绕组的非同名端和一次线圈第 2绕组的同名端为电流输入端， 辅助线圈的同名端以及二次线圈第 1绕组的非同名端为信号输出端。
实施例 12: 如图 13所示， 本实施例在实施例 11的基础上， 增设二次线圈第 2绕组的同 名端为信号输出端， 即辅助线圈的同名端、 二次线圈第 2绕组的同名端以及二次线圈第 1绕 组的非同名端为信号输出端， 当需要电流互感器的输出为三端输出信号时使用。
实施例 13: 如图 14所示， 本实施例电流互感器包括： 主磁芯 1、 第 1辅助磁芯 2、 第 2 辅助磁芯 8、 一次线圈第 1绕组 31、 一次说线圈第 2绕组 32、 二次线圈第 1绕组 41、 二次线圈 第 2绕组 42、 第 1辅助线圈 5、 第 2辅助线圈 9、 连接在二次线圈第 1绕组 41的非同名端和 二次线圈第 2绕组 42的同名端的负载电阻 6、连接书在第 1辅助线圈 5两端的第 1检测电阻 7、 连接在第 2辅助线圈 9两端的第 2检测电阻 10， 第 1检测电阻的阻值等于负载电阻的阻值， 第 2检测电阻的阻值等于负载电阻的阻值， 一次线圈第 1绕组的匝数等于一次线圈第 2绕组 的匝数， 二次线圈第 1绕组的匝数等于二次线圈第 2绕组的匝数， 第 1辅助线圈的匝数等于 二次线圈第 2绕组的匝数， 第 2辅助线圈的匝数等于二次线圈第 2绕组的匝数， 一次线圈第 1绕组和二次线圈第 1绕组绕制于主磁芯上， 一次线圈第 2绕组、二次线圈第 2绕组以及第 1 辅助线圈绕制于第 1辅助磁芯和第 2辅助磁芯上， 第 2辅助线圈绕制于第 2辅助磁芯上， 一 次线圈第 1绕组的同名端与一次线圈第 2绕组的非同名端相连接， 二次线圈第 1绕组的同名 端与二次线圈第 2绕组的非同名端相连接， 二次线圈第 2绕组的同名端与第 1辅助线圈的非 同名端相连接， 第 1辅助线圈的同名端与第 2辅助线圈的非同名端相连接， 一次线圈第 1绕 组的非同名端和一次线圈第 2绕组的同名端为电流输入端， 第 2辅助线圈的同名端以及二次 线圈第 1绕组的非同名端为信号输出端。
实施例 14: 如图 15所示， 本实施例在实施例 13的基础上， 增设二次线圈第 2绕组的同 名端为信号输出端， 即第 2辅助线圈的同名端、 二次线圈第 2绕组的同名端以及二次线圈第 1绕组的非同名端为信号输出端， 当需要电流互感器的输出为三端输出信号时使用。
实施例 15: 如图 16所示， 本实施例电流互感器包括： 主磁芯 1、 第 1辅助磁芯 2、 第 2 辅助磁芯 8、 直至第 n辅助磁芯 11、 一次线圈第 1绕组 31、 一次线圈第 2绕组 32、 二次线圈 第 1绕组 41、 二次线圈第 2绕组 42、 第 1辅助线圈 5、 第 2辅助线圈 9、 直至第 n辅助线圈 12、 连接在二次线圈第 1绕组 41的非同名端和二次线圈第 2绕组 42的同名端的负载电阻 6、 连接在第 1辅助线圈 5两端的第 1检测电阻 7、 连接在第 2辅助线圈 9两端的第 2检测电阻 10、 直至连接在第 n辅助线圈 12两端的第 n检测电阻 13， 第 1检测电阻的阻值等于负载电 阻的阻值， 第 2检测电阻的阻值等于负载电阻的阻值， 直至第 n检测电阻的阻值等于负载电 阻的阻值， 一次线圈第 1绕组的匝数等于一次线圈第 2绕组的匝数， 二次线圈第 1绕组的匝 数等于二次线圈第 2绕组的匝数， 第 1辅助线圈的匝数等于二次线圈第 2绕组的匝数， 第 2 辅助线圈的匝数等于二次线圈第 2绕组的匝数， 直至第 n辅助线圈的匝数等于二次线圈第 2 绕组的匝数， 一次线圈第 1绕组和二次线圈第 1绕组绕制于主磁芯上， 一次线圈第 2绕组、 二次线圈第 2绕组以及第 1辅助线圈绕制于第 1辅助磁芯至第 n辅助磁芯上， 第 2辅助线圈 绕制于第 2辅助磁芯至第 n辅助磁芯上， 直至第 n辅助线圈绕制于第 n辅助磁芯上， 一次线 圈第 1绕组的同名端与一次线圈第 2绕组的非同名端相连接， 二次线圈第 1绕组的同名端与 二次线圈第 2绕组的非同名端相连接， 二次线圈第 2绕组的同名端与第 1辅助线圈的非同名 端相连接， 第 1辅助线圈的同名端与第 2辅助线圈的非同名端相连接， 直至第 n-1辅助线圈 的同名端与第 n辅助线圈的非同名端相连说接， 一次线圈第 1绕组的非同名端和一次线圈第 2 绕组的同名端为电流输入端， 第 n辅助线圈的同名端以及二次线圈第 1绕组的非同名端为信 号输出端。 书
实施例 16: 如图 17所示， 本实施例在实施例 15的基础上， 增设二次线圈第 2绕组的同 名端为信号输出端， 即第 n辅助线圈的同名端、 二次线圈第 2绕组的同名端以及二次线圈第 1绕组的非同名端为信号输出端， 当需要电流互感器的输出为三端输出信号时使用。
实施例 17: 如图 18所示， 本实施例电流互感器包括： 主磁芯 1、 辅助磁芯 2、 一次线圈 第 1绕组 31、 一次线圈第 2绕组 32、 二次线圈第 1绕组 41、 二次线圈第 2绕组 42、 辅助线 圈 5， 一次线圈第 1绕组的匝数等于一次线圈第 2绕组的匝数， 二次线圈第 1绕组的匝数等 于二次线圈第 2绕组的匝数， 辅助线圈的匝数等于二次线圈第 2绕组的匝数， 一次线圈第 1 绕组和二次线圈第 1绕组绕制于主磁芯上， 一次线圈第 2绕组、 二次线圈第 2绕组以及辅助 线圈绕制于辅助磁芯上，一次线圈第 1绕组的同名端与一次线圈第 2绕组的非同名端相连接， 二次线圈第 1绕组的同名端与二次线圈第 2绕组的非同名端相连接， 二次线圈第 2绕组的同 名端与辅助线圈的非同名端相连接， 一次线圈第 1绕组的非同名端和一次线圈第 2绕组的同 名端为电流输入端， 辅助线圈的同名端、 二次线圈第 2绕组的同名端以及二次线圈第 1绕组 的非同名端为信号输出端。
实施例 18: 如图 19所示， 本实施例电流互感器包括： 主磁芯 1、 辅助磁芯 2、 一次线圈 第 1绕组 31、 一次线圈第 2绕组 32、 二次线圈第 1绕组 41、 二次线圈第 2绕组 42、 辅助线 圈 5， 一次线圈第 1绕组的匝数等于一次线圈第 2绕组的匝数， 二次线圈第 1绕组的匝数等 于二次线圈第 2绕组的匝数， 辅助线圈的匝数等于二次线圈第 2绕组的匝数， 一次线圈第 1 绕组和二次线圈第 1绕组绕制于主磁芯上， 一次线圈第 2绕组、 二次线圈第 2绕组以及辅助 线圈绕制于辅助磁芯上，一次线圈第 1绕组的同名端与一次线圈第 2绕组的非同名端相连接， 二次线圈第 1绕组的同名端与二次线圈第 2绕组的非同名端相连接， 一次线圈第 1绕组的非 同名端和一次线圈第 2绕组的同名端为电流输入端， 辅助线圈的两端、 二次线圈第 2绕组的 同名端以及二次线圈第 1绕组的非同名端为信号输出端。
实施例 19: 如图 20所示， 本实施例电流互感器包括： 主磁芯 1、 第 1辅助磁芯 2、 第 2 辅助磁芯 8、 一次线圈第 1绕组 31、 一次线圈第 2绕组 32、 二次线圈第 1绕组 41、 二次线圈 第 2绕组 42、第 1辅助线圈 5、第 2辅助线圈 9， 一次线圈第 1绕组的匝数等于一次线圈第 2 绕组的匝数， 二次线圈第 1绕组的匝数等于二次线圈第 2绕组的匝数， 第 1辅助线圈的匝数 等于二次线圈第 2绕组的匝数， 第 2辅助线圈的匝数等于二次线圈第 2绕组的匝数， 一次线 圈第 1绕组和二次线圈第 1绕组绕制于主磁芯上， 一次线圈第 2绕组、 二次线圈第 2绕组以 及第 1辅助线圈绕制于第 1辅助磁芯和第 2辅助磁芯上， 第 2辅助线圈绕制于第 2辅助磁芯 上， 一次线圈第 1绕组的同名端与一次线圈第 2绕组的非同名端相连接， 二次线圈第 1绕组 的同名端与二次线圈第 2绕组的非同名端说相连接， 二次线圈第 2绕组的同名端与第 1辅助线 圈的非同名端相连接， 第 1辅助线圈的同名端与第 2辅助线圈的非同名端相连接， 一次线圈 第 1绕组的非同名端和一次线圈第 2绕组的同名端书为电流输入端， 第 2辅助线圈的同名端、 第 1辅助线圈的同名端、 二次线圈第 2绕组的同名端以及二次线圈第 1绕组的非同名端为信 号输出端。
实施例 20: 如图 21所示， 本实施例电流互感器包括： 主磁芯 1、 第 1辅助磁芯 2、 第 2 辅助磁芯 8、 直至第 n辅助磁芯 11、 一次线圈第 1绕组 31、 一次线圈第 2绕组 32、 二次线圈 第 1绕组 41、 二次线圈第 2绕组 42、 第 1辅助线圈 5、 第 2辅助线圈 9、 直至第 n辅助线圈 12， 一次线圈第 1绕组的匝数等于一次线圈第 2绕组的匝数， 二次线圈第 1绕组的匝数等于 二次线圈第 2绕组的匝数， 第 1辅助线圈的匝数等于二次线圈第 2绕组的匝数， 第 2辅助线 圈的匝数等于二次线圈第 2绕组的匝数， 直至第 n辅助线圈的匝数等于二次线圈第 2绕组的 匝数， 一次线圈第 1绕组和二次线圈第 1绕组绕制于主磁芯上， 一次线圈第 2绕组、 二次线 圈第 2绕组以及第 1辅助线圈绕制于第 1辅助磁芯至第 n辅助磁芯上， 第 2辅助线圈绕制于 第 2辅助磁芯至第 n辅助磁芯上， 直至第 n辅助线圈绕制于第 n辅助磁芯上， 一次线圈第 1 绕组的同名端与一次线圈第 2绕组的非同名端相连接， 二次线圈第 1绕组的同名端与二次线 圈第 2绕组的非同名端相连接， 二次线圈第 2绕组的同名端与第 1辅助线圈的非同名端相连 接， 第 1辅助线圈的同名端与第 2辅助线圈的非同名端相连接， 直至第 n-1辅助线圈的同名 端与第 n辅助线圈的非同名端相连接， 一次线圈第 1绕组的非同名端和一次线圈第 2绕组的 同名端为电流输入端， 第 1辅助线圈的同名端、 第 2辅助线圈的同名端、 直至第 n辅助线圈 的同名端、 二次线圈第 2绕组的同名端以及二次线圈第 1绕组的非同名端为信号输出端。
以上对本发明的优选实施例作了详细说明， 对本领域的普通技术人员而言， 在上述具体 实施方式会有改变之处， 而这些改变也应视为本发明的保护范围。

Claims

权 利 要 求 书
1、 一种电流互感器， 其特征是： 包括主磁芯、 辅助磁芯、 一次线圈、 二次线圈、 辅助线 圈、 连接在二次线圈两端的负载电阻、 连接在辅助线圈两端的检测电阻， 检测电阻的阻值与 负载电阻的阻值的比值等于辅助线圈的匝数与二次线圈的匝数的比值， 一次线圈和二次线圈 绕制于主磁芯和辅助磁芯上， 辅助线圈绕制于辅助磁芯上， 辅助线圈的非同名端和二次线圈 的同名端相连接， 一次线圈的两端为电流输入端， 辅助线圈的同名端以及二次线圈的非同名 端为信号输出端； 或者， 辅助线圈的同名端以及二次线圈的两端为信号输出端。
2、 一种电流互感器， 其特征是： 包括主磁芯、 n 个辅助磁芯、 一次线圈、 二次线圈、 n 个辅助线圈、 连接在二次线圈两端的负载电阻、 连接在第 1辅助线圈两端的第 1检测电阻、 连接在第 2辅助线圈两端的第 2检测电阻、直至连接在第 n辅助线圈两端的第 n检测电阻， n 为大于或等于 2的整数， 第 1检测电阻的阻值与负载电阻的阻值的比值等于第 1辅助线圈的 匝数与二次线圈的匝数的比值， 第 2检测电阻的阻值与负载电阻的阻值的比值等于第 2辅助 线圈的匝数与二次线圈的匝数的比值， 以此类推， 直至第 n检测电阻的阻值与负载电阻的阻 值的比值等于第 n辅助线圈的匝数与二次线圈的匝数的比值；
一次线圈和二次线圈绕制于主磁芯和第 1辅助磁芯至第 n辅助磁芯上， 第 1辅助线圈绕 制于第 1辅助磁芯至第 n辅助磁芯上，第 2辅助线圈绕制于第 2辅助磁芯至第 n辅助磁芯上， 以此类推， 直至第 n辅助线圈绕制于第 n辅助磁芯上；
二次线圈的同名端与第 1辅助线圈的非同名端相连接， 第 1辅助线圈的同名端与第 2辅 助线圈的非同名端相连接， 以此类推， 直至第 n-1辅助线圈的同名端与第 n辅助线圈的非同 名端相连接；
一次线圈的两端为电流输入端， 第 n辅助线圈的同名端以及二次线圈的非同名端为信号 输出端； 或者， 第 n辅助线圈的同名端以及二次线圈的两端为信号输出端。
3、 一种电流互感器， 其特征是： 包括主磁芯、 辅助磁芯、 一次线圈、 二次线圈、 辅助线 圈， 一次线圈和二次线圈绕制于主磁芯和辅助磁芯上， 辅助线圈绕制于辅助磁芯上；
一次线圈的两端为电流输入端， 辅助线圈的两端以及二次线圈的两端为信号输出端； 或 者， 辅助线圈的非同名端和二次线圈的同名端相连接， 辅助线圈的同名端以及二次线圈的两 端为信号输出端。
4、如权利要求 3所述的电流互感器，其特征是：辅助磁芯的截面积小于主磁芯的截面积。
5、 一种电流互感器， 其特征是： 包括主磁芯、 n 个辅助磁芯、 一次线圈、 二次线圈、 n 个辅助线圈， n为大于或等于 2的整数， 一次线圈和二次线圈绕制于主磁芯和第 1辅助磁芯 至第 n辅助磁芯上， 第 1辅助线圈绕制于第 1辅助磁芯至第 n辅助磁芯上， 第 2辅助线圈绕 制于第 2辅助磁芯至第 n辅助磁芯上， 以此类推， 直至第 n辅助线圈绕制于第 n辅助磁芯上； 二次线圈的同名端与第 1辅助线圈的非同名端相连接， 第 1辅助线圈的同名端与第 2辅 助线圈的非同名端相连接， 以此类推， 直至第 n-1辅助线圈的同名端与第 n辅助线圈的非同 权 利 要 求 书
名端相连接；
一次线圈的两端为电流输入端， n个辅助线圈的同名端以及二次线圈的两端为信号输出
6、 一种电流互感器， 其特征是： 包括主磁芯、 辅助磁芯、 一次线圈第 1绕组、 一次线圈 第 2绕组、 二次线圈第 1绕组、 二次线圈第 2绕组、 辅助线圈、 连接在二次线圈第 1绕组的 非同名端和二次线圈第 2绕组的同名端的负载电阻、 连接在辅助线圈两端的检测电阻；
检测电阻的阻值与负载电阻的阻值的比值等于辅助线圈的匝数与二次线圈第 2绕组的匝 数的比值， 一次线圈第 1绕组的匝数与二次线圈第 1绕组的匝数的比值等于一次线圈第 2绕 组的匝数与二次线圈第 2绕组的匝数的比值；
一次线圈第 1绕组和二次线圈第 1绕组绕制于主磁芯上， 一次线圈第 2组和二次线圈第 2绕组以及辅助线圈绕制于辅助磁芯上；
一次线圈第 1绕组的同名端与一次线圈第 2绕组的非同名端相连接， 二次线圈第 1绕组 的同名端与二次线圈第 2绕组的非同名端相连接， 二次线圈第 2绕组的同名端与辅助线圈的 非同名端相连接；
一次线圈第 1绕组的非同名端和一次线圈第 2绕组的同名端为电流输入端， 辅助线圈的 同名端和二次线圈第 1绕组的非同名端为信号输出端； 或者， 辅助线圈的同名端、 二次线圈 第 2绕组的同名端以及二次线圈第 1绕组的非同名端为信号输出端。
7、 一种电流互感器， 其特征是： 包括主磁芯、 n个辅助磁芯、 一次线圈第 1绕组、 一次 线圈第 2绕组、 二次线圈第 1绕组、 二次线圈第 2绕组、 n个辅助线圈、 连接在二次线圈第 1 绕组的非同名端和二次线圈第 2绕组的同名端的负载电阻、 连接在第 1辅助线圈两端的第 1 检测电阻、 连接在第 2辅助线圈两端的第 2检测电阻、 直至连接在第 n辅助线圈两端的第 n 检测电阻， n为大于或等于 2的整数；
第 1检测电阻的阻值与负载电阻的阻值的比值等于第 1辅助线圈的匝数与二次线圈第 2 绕组的匝数的比值， 第 2检测电阻的阻值与负载电阻的阻值的比值等于第 2辅助线圈的匝数 与二次线圈第 2绕组的匝数的比值， 以此类推， 直至第 n检测电阻的阻值与负载电阻的阻值 的比值等于第 n辅助线圈的匝数与二次线圈第 2绕组的匝数的比值， 一次线圈第 1绕组的匝 数与二次线圈第 1绕组的匝数的比值等于一次线圈第 2绕组的匝数与二次线圈第 2绕组的匝 数的比值；
一次线圈第 1绕组和二次线圈第 1绕组绕制于主磁芯上， 一次线圈第 2组和二次线圈第 2绕组绕制于第 1辅助磁芯至第 n辅助磁芯上， 第 1辅助线圈绕制于第 1辅助磁芯至第 n辅 助磁芯上， 第 2辅助线圈绕制于第 2辅助磁芯至第 n辅助磁芯上， 以此类推， 直至第 n辅助 线圈绕制于第 n辅助磁芯上；
一次线圈第 1绕组的同名端与一次线圈第 2绕组的非同名端相连接， 二次线圈第 1绕组 权 利 要 求 书
的同名端与二次线圈第 2绕组的非同名端相连接， 二次线圈第 2绕组的同名端与第 1辅助线 圈的非同名端相连接， 第 1辅助线圈的同名端与第 2辅助线圈的非同名端相连接， 以此类推， 直至第 n-1的同名端与第 n辅助线圈的非同名端相连接；
一次线圈第 1绕组的非同名端和一次线圈第 2绕组的同名端为电流输入端， 第 n辅助线 圈的同名端和二次线圈第 1绕组的非同名端为信号输出端； 或者， 第 n辅助线圈的同名端、 二次线圈第 2绕组的同名端、 二次线圈第 1绕组的非同名端为信号输出端。
8、 一种电流互感器， 其特征是： 包括主磁芯、 辅助磁芯、 一次线圈第 1绕组、 一次线圈 第 2绕组、 二次线圈第 1绕组、 二次线圈第 2绕组、 辅助线圈；
一次线圈第 1绕组的匝数与二次线圈第 1绕组的匝数的比值等于一次线圈第 2绕组的匝 数与二次线圈第 2绕组的匝数的比值；
一次线圈第 1绕组和二次线圈第 1绕组绕制于主磁芯上， 一次线圈第 2绕组和二次线圈 第 2绕组以及辅助线圈绕制于辅助磁芯上；
一次线圈第 1绕组的同名端与一次线圈第 2绕组的非同名端相连接， 二次线圈第 1绕组 的同名端与二次线圈第 2绕组的非同名端相连接；
一次线圈第 1绕组的非同名端和一次线圈第 2绕组的同名端为电流输入端， 辅助线圈的 两端和二次线圈第 2绕组的同名端以及二次线圈第 1绕组的非同名端作为信号输出端；或者， 二次线圈第 2绕组的同名端与辅助线圈的非同名端相连接， 辅助线圈的两端以及二次线圈第 1绕组的非同名端作为信号输出端。
9、如权利要求 8所述的电流互感器，其特征是：辅助磁芯的截面积小于主磁芯的截面积。
10、 一种电流互感器， 其特征是： 包括主磁芯、 n个辅助磁芯、 一次线圈第 1绕组、 一 次线圈第 2绕组、 二次线圈第 1绕组、 二次线圈第 2绕组、 n个辅助线圈， n为大于或等于 2 的整数；
一次线圈第 1绕组的匝数与二次线圈第 1绕组的匝数的比值等于一次线圈第 2绕组的匝 数与二次线圈第 2绕组的匝数的比值；
一次线圈第 1绕组和二次线圈第 1绕组绕制于主磁芯上， 一次线圈第 2绕组和二次线圈 第 2绕组以及第 1辅助线圈绕制于第 1辅助磁芯至第 n辅助磁芯上， 第 2辅助线圈绕制于第 2辅助磁芯至第 n辅助磁芯上， 以此类推， 直至第 n辅助线圈绕制于第 n辅助磁芯上；
一次线圈第 1绕组的同名端与一次线圈第 2绕组的非同名端相连接， 二次线圈第 1绕组 的同名端与二次线圈第 2绕组的非同名端相连接， 二次线圈第 2绕组的同名端与第 1辅助线 圈的非同名端相连接， 第 1辅助线圈的同名端与第 2辅助线圈的非同名端相连接， 以此类推， 直至第 n-1的辅助线圈同名端与第 n辅助线圈的非同名端相连接；
一次线圈第 1绕组的非同名端和一次线圈第 2绕组的同名端为电流输入端， 第 1辅助线 圈的同名端、 第 2辅助线圈的同名端、 直至第 n辅助线圈的同名端、 二次线圈第 2绕组的同 名端、 二次线圈第 1绕组的非同名端为信号输出端。
PCT/CN2013/077581 2012-06-21 2013-06-20 一种电流互感器 WO2013189297A1 (zh)

Applications Claiming Priority (2)

Application Number Priority Date Filing Date Title
CN201210209079.X 2012-06-21
CN201210209079.XA CN102709042B (zh) 2012-06-21 2012-06-21 一种电流互感器

Publications (1)

Publication Number Publication Date
WO2013189297A1 true WO2013189297A1 (zh) 2013-12-27

Family

ID=46901727

Family Applications (1)

Application Number Title Priority Date Filing Date
PCT/CN2013/077581 WO2013189297A1 (zh) 2012-06-21 2013-06-20 一种电流互感器

Country Status (2)

Country Link
CN (1) CN102709042B (zh)
WO (1) WO2013189297A1 (zh)

Cited By (2)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN109683009A (zh) * 2019-01-17 2019-04-26 上海崇林汽车电子有限公司 一种大量程高精度霍尔电流传感器的磁路装置
WO2023028986A1 (en) * 2021-09-03 2023-03-09 Abb Schweiz Ag Winding assembly and current transformer

Families Citing this family (9)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN102709042B (zh) * 2012-06-21 2015-06-10 陈德才 一种电流互感器
CN104090146B (zh) * 2014-07-24 2017-01-18 中国科学院上海应用物理研究所 一种交直流电流传感器
CN104332297A (zh) * 2014-09-19 2015-02-04 国家电网公司 微机保护装置用电流互感器
CN106298214B (zh) * 2016-09-23 2018-01-09 国网江西省电力公司电力科学研究院 一种宽量程零磁通电流比例变换器
CN107424815B (zh) * 2017-08-18 2019-04-30 陈宇斯 一种采用减匝补偿的双级电流互感器
CN108039267B (zh) * 2017-11-25 2019-10-25 华为数字技术（苏州）有限公司 电流互感器
CN109754998B (zh) * 2019-03-06 2020-07-21 陈德才 一种有源双级电流互感器
CN111785510B (zh) * 2020-07-01 2022-03-15 南京丹迪克电力仪表有限公司 一种制备高准确级双级钳形电流互感器的方法
CN113161134A (zh) * 2021-04-15 2021-07-23 上海置信智能电气有限公司 抗直流分量双级电流互感器

Citations (5)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
DE2632377C2 (zh) * 1976-07-19 1987-10-01 Richard Dr.-Ing. Friedl
WO1996001432A1 (en) * 1994-07-01 1996-01-18 Rmd Electronics Pty. Ltd. Improved clipon ct
CN2221216Y (zh) * 1995-02-06 1996-02-28 电力工业部电力科学研究院 小电流高准确度的电流传感器
US20030013782A1 (en) * 2001-07-02 2003-01-16 David Burnett Friction pads and disks and compositions and methods for producing same
CN102709042A (zh) * 2012-06-21 2012-10-03 陈德才 一种电流互感器

Family Cites Families (2)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN1020520C (zh) * 1990-08-02 1993-05-05 李保业 高导磁特性的电流互感器
US6903642B2 (en) * 2001-12-03 2005-06-07 Radian Research, Inc. Transformers

Patent Citations (5)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
DE2632377C2 (zh) * 1976-07-19 1987-10-01 Richard Dr.-Ing. Friedl
WO1996001432A1 (en) * 1994-07-01 1996-01-18 Rmd Electronics Pty. Ltd. Improved clipon ct
CN2221216Y (zh) * 1995-02-06 1996-02-28 电力工业部电力科学研究院 小电流高准确度的电流传感器
US20030013782A1 (en) * 2001-07-02 2003-01-16 David Burnett Friction pads and disks and compositions and methods for producing same
CN102709042A (zh) * 2012-06-21 2012-10-03 陈德才 一种电流互感器

Cited By (2)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN109683009A (zh) * 2019-01-17 2019-04-26 上海崇林汽车电子有限公司 一种大量程高精度霍尔电流传感器的磁路装置
WO2023028986A1 (en) * 2021-09-03 2023-03-09 Abb Schweiz Ag Winding assembly and current transformer

Also Published As

Publication number Publication date
CN102709042A (zh) 2012-10-03
CN102709042B (zh) 2015-06-10

Similar Documents

Publication Publication Date Title
WO2013189297A1 (zh) 一种电流互感器
US11525848B2 (en) Current detecting circuit of power converter
CN103592490B (zh) 一种高准确度电子补偿式电流互感器
TW200535876A (en) DC transformer with output inductor integrated on the magnetic core thereof and a DC/DC converter employing the same
CA2148961A1 (en) Linear Alternating Current Interface for Electronic Meters
KR100882727B1 (ko) 로고스키 센서를 이용한 전류 측정장치
US20200088769A1 (en) Current sensing device, method and system
CN107424815B (zh) 一种采用减匝补偿的双级电流互感器
CN202189670U (zh) 组合式电流变换器
CN104849532B (zh) 一种精密电流传感器
CN110118889B (zh) 一种双级电流传感器
CN106328349A (zh) 一种双二次绕组双级电压互感器
CN203606413U (zh) 一种高准确度电子补偿式电流互感器
CN204067022U (zh) 综合误差补偿型互感器
JPWO2009098824A1 (ja) トランスおよびトランス装置
TWI643222B (zh) 整合型變壓器
CN109754998B (zh) 一种有源双级电流互感器
CN113391110A (zh) 一种有源抗直流分量的电流互感器
CN113161134A (zh) 抗直流分量双级电流互感器
CN107765057B (zh) 一种双级电流互感器
CN107037252B (zh) 电子补偿式感应分流器
CN107942123B (zh) 一种直流电流测量装置
CN102360885A (zh) 组合式电流变换器
CN210865892U (zh) 一种异型防强磁场的抗直流分量电流互感器
CN109036812B (zh) 电流采集装置

Legal Events

Date Code Title Description
121 Ep: the epo has been informed by wipo that ep was designated in this application

Ref document number: 13806969

Country of ref document: EP

Kind code of ref document: A1

NENP Non-entry into the national phase

Ref country code: DE

122 Ep: pct application non-entry in european phase

Ref document number: 13806969

Country of ref document: EP

Kind code of ref document: A1